Bovine fasciolosis is caused by two liver fluke species, Fasciola hepatica and Fasciola gigantica. It is a widely distributed disease affecting cattle globally wherever suitable intermediate snail hosts are present. The life cycle is indirect, involving Lymnaeid snails as intermediate hosts. Clinical signs vary depending on infection level and include weight loss, anemia, and bottle jaw. Diagnosis involves examining feces for fluke eggs, blood tests, and post-mortem liver inspection. The disease causes major economic losses due to treatment costs, production losses, and liver condemnation. It is also an important public health problem infecting over 2 million people worldwide. In Ethiopia, fasciolosis

1. REVIEW ON BOVINE FASCIOLOSIS AND ITS IMPORTANCE
BY
ABIYU MULUKEN (5th
Year)
“A seminar paper presented for the course: seminar animal health (Vetm 5223)”
College of Veterinary Medicine
Department of Veterinary Medicine
Advisor: Biyansa Adugna (DVM, Assist. Msc)
May, 2017
Samara, Ethiopia

2. I
ACKNOWLEDGEMENTS
First of all, I would like to praise almighty God who helped me in every aspect and condition for
my success to review this paper.
Secondly, I wish to sincerely express my profound thanks to my advisor Dr. Biyansa Adugna for
his motivation, technical advice, encouragement, material supply, guidance and valuable
comments to have the paper its shape and devotion of his time in correction of this paper.
I would like to sincerely thank Samara University, College of Veterinary Medicine for offering
the opportunity to allowing using the instrument and provision the necessary materials for the
preparation of this paper. At last I would like to thank my colleagues for their cooperation and all
individuals who render help during all my study are highly acknowledged.

3. II
TABLE OF CONTENT
Page
ACKNOWLEDGEMENTS...........................................................................................................I
TABLE OF CONTENT............................................................................................................... II
LIST OF TABLES...................................................................................................................... III
LIST OF FIGURES.................................................................................................................... IV
LIST OF ABBREVIATIONS......................................................................................................V
SUMMARY................................................................................................................................. VI
1. NTRODUCTION.......................................................................................................................1
1.1. Etiology and morphology.......................................................................................................3
1.2. Epidemiology...........................................................................................................................4
1.2.1. Geographical Distribution..................................................................................................... 4
1.2.2. Risk factors associated with bovine Fasciolosis....................................................................6
1.2.3. Life cycle and mode of transmissions................................................................................... 7
1.3. Pathogenesis............................................................................................................................ 9
1.4. Clinical manifestation...........................................................................................................10
1.5. Diagnosis................................................................................................................................11
1.5.1. History and clinical sign......................................................................................................12
1.5.2. Parasitological methods.......................................................................................................12
1.5.3. Serological examination...................................................................................................... 14
1.5.4. Molecular methods.............................................................................................................. 14
1.6. Treatment..............................................................................................................................15
1.7. Prevention and control.........................................................................................................16
2. IMPORTANCE OF FASCIOLOSIS.....................................................................................18
2.1. Economic importance...........................................................................................................18
2.2. Public health importance..................................................................................................... 19
3. STATUS OF BOVINE FASCIOLOSIS IN ETHIOPIA......................................................21
4. CONCLUSION AND RECOMMENDATIONS...................................................................22
REFERENCE...............................................................................................................................23

4. III
LIST OF TABLES
Page
Table 1: The taxonomic classification of the organisms that cause fasciolosis..............................3
Table 2: Global prevalence of bovine fasciolosis...........................................................................5
Table 3: The total annual economic losses encountered due to condemnation of infected liver in
different abattoirs and slaughter houses of Ethiopia......................................................................19
Table 4: Prevalence of fasciolosis in different areas of Ethiopia on bovine.................................21

5. IV
LIST OF FIGURES
Page
Figure 1: Morphology of fasciola specious.................................................................................... 4
Figure 2: Life cycle of fasciola.......................................................................................................9
Figure 3: Fasciola hepatica egg in an unstained wet mount (400 x magnifications)...................13
Figure 4: Rumen and liver fluke eggs...........................................................................................15

6. V
LIST OF ABBREVIATIONS
CDC Centers for Disease Control and Prevention
CSA Community Supported Agriculture
ELISA Enzyme-Linked Immunosorbent Assay
ETB Ethiopian Birr
IH Interment Host
ILRI International Live Stock Institution
LAMP Loop Mediated Isothermal Amplification
NADIS National Animal Disease Information
PCR Polymerize Chain Reaction
SPP Specious
USA United State of America

7. VI
SUMMARY
Fasciolosis is one of the most important helminth infections of ruminant livestock and caused by
Fasciola hepatica and Fasciola gigantica. This disease is widely distributed in areas where cattle
are raised and there is a niche for lymnaeid snail, Fasciola hepatica found in temperate area and
Fasciola gigantica, which predominates found in tropical area. The disease is found in vast
water lodged and marshy grazing field condition anticipated to be ideal for the propagation and
maintenance of high prevalence of fasciolosis. The life cycle of these trematodes is indirect and
Lymnaeide snail specious as an intermediate host (IH).The development of infection in definitive
host is divided into two phases: the parenchymal (migratory) phase and the biliary phase. The
disease is usually characterized by a chronic, sometimes acute or sub-acute inflammation of the
liver and bile ducts, accompanied by sub-mandibular oedema, anaemia, anorexia, general
intoxication and death. Diagnosis of bovine fasciolosis is based on clinical sign, grazing history,
seasonal occurrence, examination of faces by laboratory tests and post-mortem examination.
Triclabendazole is considered as the most common drug due to its high efficacy against adult as
well juvenile flukes. In cattle, chronic form of the disease is more common and drugs like
rafoxanide and nitroxynil other than triclabendazole are more effective. The disease can be
controlled by reducing the population of the intermediate host or regular deworming of cattle by
using antihelemntics. Fasciolosis causes significant economic loss to livestock especially in
cattle and sheep. The economic losses include indirect cost such as costs of antihelemntics, labor,
and secondary infection. Direct economic losses included losses due to mortality, morbidity and
loss of liver due to condemnation. Fasciolosis has also been recognized as reemerging and
widespread zoonotic disease affecting millions of people worldwide and many more are at the
risk of infestation.
Key words: Fasciolosis, Bovine, Ethiopia, Antihelemntics, Snail, Liver.

8. 1
1. INTRODUCTION
Developing countries have nearly two third of the world’s livestock production but produces less
than a third of the world’s meat and a fifth of its milk (Addis et.al., 2015).Similarly, Ethiopia is
one of the countries endowed with large and diverse livestock resources of which cattle accounts
53,990,061(CSA, 2013). However, many factors affect the maximum benefit to be obtained from
livestock production and parasitic diseases are the major factors (ILRI, 2009). Parasitic
infections have great economic impact, especially in developing countries including Ethiopia
(Hunter, 2000). Fasciolosis is among important parasitic diseases in tropical and subtropical
countries which limit productivity of ruminants in particular cattle. It is an economically
important parasitic disease which is caused by trematodes of the genus Fasciola that migrate in
the hepatic parenchyma, and establish and develop in the bile ducts and it is commonly
recognized as liver flukes that are responsible for wide spread of morbidity and mortality in
cattle characterized by weight loss, anemia and hypoproteinemia.
The two most important species are Fasciola hepatica found in temperate area and cooler areas
of high altitude in the tropics and subtropics and Fasciola gigantica, which predominates found
in tropical area (Mugugeta et al., 2011). The disease is found in vast water lodged and marshy
grazing field condition expected to be ideal for the propagation and maintenance of high
prevalence of Fasciola. In Ethiopia, the highlands contain pockets of water logged marshy areas
and these provide suitable habitats year round for the snail intermediate hosts (Solomon and
Abebe, 2007).Both Fasciola hepatica and Fasciola gigantica are transmitted by the snails of the
family lymnae (Lymnaea auricularia and Lymnaea truncatula). Infestation with fasciolosis is
usually associated with grazing wet land and drinking from the snail infested watering places
(Dechasa et al., 2012).
The pathogenesis of Fasciolosis varies according to the parasitic development phases:
parenchymal and bilary phases (Admassu et al., 2015). Clinical signs are closely associated with
the severity of the disease which is determined by the level of infection, nutritional plane of the
animal and also on the individual host species and breed (Abdisa, 2017). Fasciolosis can be
classified as acute, sub-acute or chronic. The chronic fasciolosis is the most common form of the
disease in cattle. It occurs when the parasite reaches the hepatic bile duct (Michael, 2004).
Animal become emaciated, have pale eye and gums and typically develop “bottle jaw” due to
edema under the jaw (Bemrew et al., 2015). Diagnosis is based primarily on clinical signs and

9. 2
seasonal occurrence in endemic areas but previous history of Fasciolosis on the area of snail
habitats; postmortem examinations, hematological tests and examination of faces for fluke eggs
are useful. Carpological analysis is commonly employed to diagnose Fasciolosis, despite the fact
that eggs cannot be detected until the latent period of infections (Rokni et al., 2003).
The economic losses due to fasciolosis are caused by mortality, morbidity, and reduced growth
rate, condemnation of liver, increased susceptibility to secondary infections and the expense of
treatment cost and control measures (Ibrahim et al., 2009).In general, infection of domestic
ruminants with Fasciola hepatica and Fasciola gigantica causes significant economic loss
estimated at over US $200 million per annum to the worldwide and 600 million animals’
infected (Mihret et al., 2015) .The annual loss due to endoparasites in Ethiopia is estimated at
700 million Ethiopian birr/annum (Michael, 2004).
Among the zoonotic parasitic diseases, human fascioliasis is currently classified as a plant/food-
borne trematode infection, with higher prevalence seen among farming communities in low
income countries (Janneh, 2016). Human becomes infected when metacercariae of the fluke is
ingested along with water Cress Salad and vegetables grown along banks of water reservoirs
inhabited by potential snail hosts. About 2.4 million people are infected world wide and 180
million are at risk of the infection. In Africa, the infection has been found to be a serious
problem in humid and sub-humid zones (Ekenma, 2015).
Therefore, the objectives of this review paper are:
 Review about bovine fasciolosis
 Provide some information about epidemiology and pathogenesis of the disease,
 The importance of bovine Fasciolosis

10. 3
1.1. Etiology and morphology
Fasciolosis is caused by digenean of the genus Fasciola commonly referred to as liver flukes.
The two species most commonly implicated as the etiological agents of fasciolosis are Fasciola
hepatica and Fasciola gigantica (Khaled et al., 2010).
Table 1: The taxonomic classification of the organisms that cause Fasciolosis
Taxonomy
Kingdom Animalia
Phylum Platyhelminthes
Class Trematoda
Order Digenea
Family Fasciolae
Genus Fasciola
Species Fasciola hepatica and Fasciola gigantica
Source: (Saria, 2011)
The two species have been traditionally classified based on their morphological features, such as
body length and width. Because of variations in size of these two species, the discrepancy of
morphological features, and the presence of intermediate forms, it might be difficult to
distinguish the two species, solely based on these characters (Abdisa, 2017). Fasciola gigantica
is larger than Fasciola hepatica and can reach 7.5 cm length. The shape is more of leaf like, the
conical anterior end is very short and the shoulder characteristic of Fasciola hepatica is barely
perceptible. The eggs are larger than those of F. hepatica, measuring 190 × 100 μm (Valero et al.,
2001).
Fasciola hepatica is a leaf shaped fluke with broader anterior and cone shaped anterior
projection. It is grayish brown in color changing to gray when preserved. The young fluke at the
time of entry in to the liver is 1 - 2 mm in length and lancet like when it has become fully mature
in the bile ducts. It is leaf-shaped gray brown in color and is around 2.5 - 3.5 cm in length and 1
cm in width. The anterior end is conical and marked off by distinct shoulders from the body
(Abdisa, 2017). The egg of Fasciola hepatica measures 150 x 90 μm in size and also similar in

11. 4
shape to that of Fasciola gigantica. Fasciola eggs should be distinguished from the eggs of other
flukes, especially from the large eggs of paramphistomum (Abdisa, 2017).
Source: (Abdisa, 2017)
Figure 1: Morphology of fasciola specious
1.2. Epidemiology
The epidemiology of fasciolosis depends on the grazing habitat preference of the animal.
Metacercariae can survive up to 3 months after harvesting in hay from endemic high land areas
that are consumed by ruminants in arid and low land areas (Ibrahim et al., 2009, Terefe et al.,
2012). Wet land and blocked drainage area are hazardous for grazing stock (Radostits et al,
2007).
1.2.1. Geographical Distribution
The live fluke’s distribution is worldwide in areas where cattle, sheep and goat are raised and
there is a niche for Laymnaeid snail (Marquardt, 2000). Fasciola hepatica, which is a temperate
species, is the mostly important trematodes of domestic ruminant and common causes of liver
fluke disease in temperate areas of the world. Thus, it is found in Southern and Northern

12. 5
America, Europe, Australia and Africa. Fasciola gigantica, on the other hand, is economically
important and widely distributed in tropical countries of Africa and Asia (Khan, 2005).
The risk of hepatic fasciolosis is determined by the number of infected Lymnae snails in the
grazing area. The disease has a predictable seasonal pattern in regions where snails are active for
only part of the year. Some Lymnae snails have more aquatic habit than others but most are
restricted to damp (Maqbool, et al., 2002). In tropical regions, Fasciolosis is considered as the
single most important helminthes infection of cattle with the prevalence rate of 30% - 90% in
Africa, 25% - 100% in India and 25% - 90% in Indonesia (Ali et al., 2011). In Ethiopia, Fasciola
gigantica is found at altitudes below 1800 meter below sea level while Fasciola hepatica is
found at altitudes between 1200-2560 meters above sea level. Mixed infection by the two species
can be encountered at 1200-1800 meter above sea level (Asressa et al., 2012).
Table 2: Global prevalence of bovine fasciolosis
Continents/Region Country Prevalence (% Species
Africa Algeria 17 F. hepatica
Egypt 29 F. hepatica
Ethiopia 14-24 F. hepatica
Kenya 7-26 F. gigantica
Asia China 12-27 F. gigantica
India 11-25 F. gigantica
Indonesia 25-48 F. gigantica
Philippines 45 F. gigantica
Caribbean Jamaica 22 F. hepatica
Oceania Australia 5 F. hepatica
New Zealand 30 F. hepatica
Middle East Iran 2-32 F. gigantica
Turkey 65 F. gigantica
Americans United states 6-68 F. hepatica
Canada Up to 68 F. hepatica
Brazil 1-20 F. hepatica

13. 6
Europe Belgium 13 F. hepatica
Germany 11 F. hepatica
France 17 F. hepatica
Italy 5 F. hepatica
United kingdom 10 F. hepatica
Source: (Mochankana, 2014)
1.2.2. Risk factors associated with bovine Fasciolosis
The main factors determining the timing and severity of Fasciolosis depend on the number of
metacercariae accumulating on herbage. Particularly, temperature and rainfall affect both the
spatial and temporal abundance of snail hosts and the rate of development of fluke eggs and
larvae. The most important factors that influence the occurrence of Fasciolosis are availability of
suitable snail habitat, temperature, moisture and host rage (Mihret et al., 2015).
Availability of Suitable Snail Habitat: One of the most important factors that influence the
occurrence of fasciolosis in an area is availability of suitable snail habitat. The snail habitat may
be permanent or temporary. The availability of these intermediate hosts depends on climatic
conditions for instance, L. truncatuala prefers wet mud to free water and permanent habitat
includes the ban of ditches or streams and edges of small ponds. Fields with clumps of rushes are
often suspect site. Through a slightly acid pH environment is optimal for L. truncatula,
excessively acid pH levels are detrimental (Admassu et al., 2015).
Temperature: It is an important factor affecting the rate of development of snails and the stages
of the parasite outside the final host. A mid -day or night temperature of 10°c or above is
necessary for both snails to breed and for the development of Fasciola hepatica within the snail
and all activity cease at 5°c (Admassu et al., 2015). Fasciola cercaria stage and Lymnaea snails
have been found to survive better at 25-30°c which explains in parts at least, the much higher
prevalence in autumn compared to other seasons (Admassu et al., 2015).
Moisture: The ideal moisture conditions for breeding and development of Fasciola within snails
are provided when rainfall exceeds transpiration and field saturation is attained. Such conditions

14. 7
are also essential for the development of fluke eggs, for miracidium to search for snails and for
the dispersal of cercaria shed from the snails (Maqbool et al., 2002).
Host range: Intermediate host of Fasciolosis is determined by the number of infected lymnaeid
snails in the grazing area. The disease is seasonal pattern in regions where snails are active for
only part of the year. Some lymnaeid snails have more aquatic habitat than others but most are
restricted to damp or wet environments. In general, non acidic, low lying swampy areas with
slow moving water and irrigated areas are highly suitable for infection to takes place. Snails
burrow in to the soil to survive dry periods and release cercaria when free water is present
(Radostits et al., 2007).Evidence suggests that sheep and cattle are the main reservoir host
species (Mihret et al., 2015).
Intermediate host: The snails of the genus Lymnae are the IHs for the genus Fasciola. The
epidemiology of Fasciolosis depends on the ecology of the snail. Lymnae species most important
in transmission of Fasciola hepatica is L. truncatula, widespread in Australia. Other species,
which have been incremented in the transmission of Fasciolosis, include L. viator and L.
diaphone (South America), L. celummella (USA, Australia, Central America and Netherland)
and L. humilis in Northern America (Tsega et al., 2015). The most important IHs of Fasciola
gigantica is L. natalensis and L. auricularia (Ali et al., 2011).
Final host: Hosts of Fasciola hepatica are most mammals including man, sheep and cattle being
most important. Fasciola gigantica affects a wide range of domestic animals and is found in low
land areas replacing Fasciola hepatica (Radostits et al., (2007). Infection is by ingestion of
contaminated grass or hay and transmission to lamb in utero is possible but infrequent (Tsega et
al., 2015). Adult sheep and cattle may remain carriers for many years because of the longevity of
the adult flukes (Radostits et al., 2007).
1.2.3. Life cycle and mode of transmissions
For the life cycle of Fasciola species occurring in any particular area the following conditions
must be satisfied. There must be an initial presence of infected final hosts (where the adult worm
lives), the intermediate snail host (where the larval stages of the worm develop) must be present
and there must be an opportunity for transmission of the parasite from the final host to the snail
habitat or carrier (entailing suitable aquatic plants) (Mahato et al., 2000).

15. 8
The life cycle of fasciola is complex and always indirect, involving intermediate hosts before
invasion of definitive hosts. (Kahn, 2005).Lymnea truncatula is the most important intermediate
host for Fasciola hepatica while L. natalensis and L. auricularia are among the main
intermediate host species for Fasciola gigantica (Addis et al., 2015).
The process starts when infected animals (cattle, sheep, buffaloes, donkeys and pigs but also
horses, goats, dromedaries, camels, llamas and other herbivores) defecate in fresh-water sources.
Since adult liver flukes reside in the bile ducts of host animals, and eggs are passed onto the
pasture in the feces. After a short period of development (usually 2 to 3 weeks), a miracidium
hatches from the egg and attempts to find and penetrate a snail intermediate host. The parasite
develops and replicates asexually in the snail over many weeks. Under optimal conditions,
parasite maturation within the snail to the cercarial stage takes approximately 5 to 7 weeks, and a
single miracidium can develop into several hundred cercariae. Under wet conditions, cercariae
emerge from the snail and swim until they find and attach to vegetation. The cercariae then shed
their tails and secrete a protective coat, forming the encysted infective stage called metacercariae.
Cattle become infected primarily by ingesting the metacercariae cysts on forage, but they also
can become infected by ingesting cysts suspended on soil and detritus while drinking
contaminated water. The length of time that metacercariae survive on pasture primarily depends
on available moisture. Under hot and dry pasture conditions metacercariae rapidly die; however,
under conditions of high humidity, metacercariae may survive for extended periods. Once
ingested by a ruminant host, the metacercariae excyst, releasing juvenile flukes (Kaplan, 2001).
The juvenile flukes penetrate the wall of the small intestine, migrate through the peritoneal
cavity over a week’s time, and then penetrate through the liver capsule. Juvenile flukes migrate
through the hepatic parenchyma for approximately 6 to 8 weeks before entering the bile ducts
where they mature. Egg production can begin as early as 8 weeks after infection however, most
infections do not become patent until after approximately 11 to 12 weeks. Thus, completion of
the entire parasite life cycle, from the time an egg is shed on to pasture until a newly infected
animal re infects the pasture with the next generation of fluke eggs, generally requires 18 to 24
weeks (4.5 to 6 months (Kaplan, 2001). Infestation with Fasciolosis is usually associated with
grazing wet land and drinking from the snail infesting watering places (Terefe et al., 2012).When
the plants with the small cysts attached are ingested, they act as carriers of the infection. Humans

16. 9
and animals get infected by eating aquatic plants and by grazing, respectively, and by drinking
water contaminated with metacercariae (Addis et al., 2015).
Source: (CDC, 2013 parasite, fasciolosis (Fasciola infection) at:
(https://www.cdc.gov/dpdx/fascioliasis/index.html).
Figure 2: Life cycle of Fasciola
1.3. Pathogenesis
The development of infection in definitive host is divided into two phases: the parenchymal
(migratory) phase and the biliary phase (Sheama et al., 2010). The parenchymal phase begins
when encysted juvenile flukes penetrate the intestinal wall. After the penetration of the intestine,
flukes migrate within the abdominal cavity and penetrate the liver or other organs. F. hepatica
has a strong predilection for the tissues of the liver and is associated with liver damage and

17. 10
hemorrhage (Abdisa, 2017, Bemrew et al., 2015). The principal pathogenic effects of flukes are
anemia and hypo albuminaemia. More than 0.5 ml blood per fluke per day can be lost within the
bile duct (Salam et al., 2009).Occasionally, ectopic locations of flukes such as the lungs,
diaphragm, intestinal wall, kidneys, and subcutaneous tissue can occur (Valero and Mas-Com,
2000) During the migration of flukes, tissues are mechanically destroyed and inflammation
appears around migratory tracks of flukes.
The second phase (the biliary phase) begins when parasites enter the biliary ducts of the liver. In
biliary ducts, flukes mature, feed on blood, and produce eggs. Hypertrophy of biliary ducts
associated with obstruction of the lumen occurs as a result of tissue damage (Sheama et al.,
2010).The pathogenesis of bovine fasciolosis is similar to that in sheep but has the added
features of calcification of the bile ducts and enlargement of gall bladder. Although acute and
sub-acute disease may occasionally occur under condition of heavy challenges especially in
young calves, chronic form of the disease is by far the most as sheep seen in the late winter or
early spring (Bemrew et al., 2015).
In general adverse effect of fasciolosis is caused by three ways: Mechanical (obstruction of
parenchyma and blood vessels of the liver by immature flukes burrowing through the liver and
irritation of the epithelia lining of the bile ducts by the adult); toxic (by secretary and excretory
product of the fluke); and loss of blood resulting from hemorrhage in the liver (acute form) and
hematophagous feeding habits of the flukes (Bemrew et al., 2015).
1.4. Clinical manifestation
Clinical signs of fasciolosis are always closely associated with infectious dose (amount of
ingested metacercariae).The clinical features of Fasciolosis can have acute, sub-acute and
chronic forms. Acute Fasciolosis occurs as disease outbreak following a massive, but relatively
short-term, intake of metacercariae (Bemrew et al., 2015).
Acute Fasciolosis: It occurs when large numbers of the immature stages of fluke migrate
simultaneously through the liver parenchyma of the definitive host. This normally occurs from
October through to spring after animals become infected in the summer or from late spring until
early summer if initially infected during winter. Acute fasciolosis may cause sudden death in
sheep and has been reported to cause losses of up to 25% of the animals within flocks

18. 11
(McDougall, 2012). Cattle rarely die from the acute form of the disease unless very young calves
are subject to a large intake of metacercariae (Dalton et al., 2003). The extensive tissue damage
caused by the migration of juvenile can result in a reduction of liver function and intraperitoneal
hemorrhage). This is often characterized by anemia, weight loss, diarrhea and an enlargement of
the liver but infected animals often show no symptoms of an acute infection. Acute infections in
dairy herds have been reported to result in significant production losses and extended periods
between calving (McDougall, 2012).
Sub-acute Fasciolosis: is caused by ingestion of a moderate number of metacercariae and is
characterized by jaundice, some ill thrift and anemia. The burrowing fluke causes extensive
tissue damage, leading to hemorrhage and liver damage. The outcome is severe anemia, liver
failure (and death in 8–10 weeks (Boray,2007).Sub acute fasciolosis normally peaks between
October and January after a large intake of metacercariae but over a more prolonged period than
that causing the acute form. Furthermore, both adult and immature flukes can be present
simultaneously (Abbott et al., 2009).
Chronic Fasciolosis: is the most common clinical syndrome in sheep and cattle. It occurs when
the parasite reaches the hepatic bile duct. The principal effects are bile duct obstruction,
destruction of liver tissue, hepatic fibrosis and anemia. The onset of clinical signs is slow
animals become anemic and anorectic, as the adult fluke becomes active within the bile duct and
signs may include: dependent edema or swelling under the jaw (‘bottle jaw’). Affected animals
are reluctant to travel. Death eventually occurs when anemia becomes severe. Additional stress
upon anemic animals, such as droving, may lead to collapse and death. Cattle typically present
with signs of weight loss (emaciation), reproductive dysfunction and chronic diarrhea (Mitchell,
2003).
1.5. Diagnosis
A tentative diagnosis of Fasciolosis may be established based on prior knowledge of
epidemiology of the disease in a given environment, observation of clinical sign, information on
grazing history, seasonal occurrence, and identification of snail habitats. Confirmatory diagnosis
however, is based on demonstration of Fasciola spp. eggs through standard examination of feces
in the laboratory, post mortem examination of infected animals, molecular and immunological
methods (Terefe et al., 2012).

19. 12
1.5.1. History and clinical sign
In animals, the clinical features of Fasciolosis present in different forms, depending on the
animal species, the level of infection and the plane of nutrition of the animals. Sign may also
vary between animals within a group. Acute Fasciolosis may cause sudden death and is mostly
seen in sheep and goats, as a result of intake of large numbers of larvae over a short period. A
history of grazing fluke-prone areas is usually found. Animals presenting with the chronic form
of Fasciola specious infection often show no specific clinical signs, which makes diagnosis
difficult. However, weight loss, pale mucous membranes, ventral edema (‘bottle jaw’) and
diarrhea can be observed in this stage in both sheep and cattle. The most important feature of
chronic fasciolosis is loss of production, mainly through reduction in weight gain, milk yield and
fertility (Giang, 2012).
1.5.2. Parasitological methods
Parasitological diagnosis of Fasciolosis is based on examination for presence of immature or
adult flukes in the liver, bile ducts and gall bladder, at slaughter or autopsy, and on the
demonstration of fluke eggs by coprological examination (Giang, 2012).
Faecal examination: Detection of liver fluke eggs in faeces samples is a very simple method
including flotation and sedimentation techniques, with high specificities of 93% - 100%. The
fluke eggs are heavy; therefore, the use of flotation solutions with high density is needed. (E.g.
zinc chloride and sodium chloride (d = 1.6) or potassium iodomercurate solutions). Flotation
methods are qualitative and the chemicals used are harmful for the environment. Sedimentation
techniques appear to be more accurate and sensitive than flotation techniques (Giang, 2012).
Sedimentation using tap water is the simplest and cheapest method, but it is more time
consuming compared to flotation techniques. The visibility of the eggs in the sediment can be
increased by adding a few drops of methylene blue solution. The sensitivity of this method is
only 33.3% when the fecal material contains less than 1.5 eggs per gram feces, but increases up
to 100% for higher egg concentrations (Conceiçao et al., 2002).
The eggs of Fasciola hepatica are oval in shape, brownish or yellowish brown in color. The eggs
have an indistinct operculum and develop only after the eggs have been laid. Fasciola eggs
should be distinguished from the eggs of other flukes, especially from the large eggs of

20. 13
paramphistomum. Fasciola eggs have yellowish brown shell with an indistinct operculum and
embryonic cells where as paramphistomum eggs have transparent shell, distinct operculum with
embryonic clear cells and possess a small knob at their posterior ends (Taylor et al., 2007).
Fasciola hepatica eggs are broadly ellipsoidal, and measure 130-150 x 60-90 μm (CDC, 2013).
Source: (CDC, 2013)
Figure 3: Fasciola hepatica egg in an unstained wet mount (400 x magnifications)
Postmortem examination: The detection of adult flukes in the liver at necropsy is the most
reliable method to confirm fasciolosis. Prevalence studies should be based on abattoir survey
other than coproscopic investigation (Mihret et al., 2015). Acute fasciolosis which is common in
sheep is manifested by severe anemia and sudden death. Confirmation is by post mortem
examination when small fluke can be expressed from the liver parenchyma (Wakuma, 2009).
Briefly, the gall bladder is removed, the major bile duct opened with blunt–blunt scissors and
any visible flukes were removed with blunt forceps and examine the parasite. The specificity of
liver examination is very high (93.4% to 100%) but the technique lacks sensitivity (47.4% to
63.2%) (Rapsch et al., 2006).Liver was visually scored for fibrosis. A score of one indicated no
fibrosis, two indicated medium fibrosis and three indicated severe fibrosis. (De Bont et al., 2003).
Ultrasonic detection of liver lesions can determine the extent of the tissue damage from the
parasite (Ekenma, 2015). Fasciola hepatica is one of the largest flukes , reaching a length of
30 mm and a width of 13 mm (Fasciola gigantica, on the other hand, is even bigger and can
reach up to 75 mm)( CDC, 2016):. It is leaf-shaped, pointed at the back (posteriorly) and wide in
the front (anteriorly). The oral sucker is small but powerful and is located at the end of a cone-

21. 14
shape projection at the anterior end. The acetabulum is a larger sucker than the oral sucker and is
located at the anterior end (CDC, 2016).
1.5.3. Serological examination
In vivo diagnosis of mild and prevalent infection is possible serologically. For example detection
of antibodies by ELISA in serum or milk is available and particularly useful for diagnosis of
infection in sheep in an individual or herd basis. Arise in antibodies can be detected by two
weeks after infection and keeps rises until week six (Mihret et al., 2015). There are three
Different types of ELISA available for diagnosis of fascioliasis seroELISA, coproELISA and
milk ELISA. The MM3-SERO ELISA is a sensitive and highly specific test for the sero-
diagnosis of cattle fascioliasis and can be reliable to use with milk samples. It is an excellent
method of estimating within-herd prevalence of infection when used with bulk samples (Mezo et
al., 2009, Mezo et al., 2010).
1.5.4. Molecular methods
Molecular methods are the most effective and highly sensitive for diagnosis of fasciolosis
(Martínez et al., 2010). The two common molecular techniques which used for diagnosis of
domestic fasciolosis are polymerizing chain reaction (PCR) and Loop mediated isothermal
amplification (LAMP). They are rapid, sensitive and specific and detect infection. PCR assay is
successful in identification of both species of Fasciola. This assay is validated on adult flukes
alone (Alasaad et al., 2011). The LAMP is a method of nucleic acid amplification with
extremely high sensitivity and specificity to discriminate single nucleotide differences (Parida et
al., 2008). A diagnostic LAMP assay is validated on eggs, larvae and adults of Fasciola hepatica
and Fasciola gigantica (Dong et al., 2010).
Differential Diagnoses: Weight loss and chronic diarrhea in individual cattle will also be
investigated for paratuberculosis and salmonellosis. Chronic liver fluke and paratuberculosis
have been reported in the same animal. Inadequate nutrition generally presents as a whole
group/herd problem of poor production and weight loss during the late winter months in beef
herds with diarrhea an uncommon finding unless poor quality silage is fed. Chronic Fasciolosis
is diagnosed by demonstration of fluke eggs in fecal samples (NADIS, 2012). The oval,
operculated, golden brown eggs (130–150 × 65–90 μm) must be distinguished from those of

22. 15
paramphistomes (rumen flukes), which are larger and clear. Eggs of Fasciola hepatica cannot be
demonstrated in feces during acute fasciolosis (Lora, 2016).
Source: (Admassu et al., 2015)
Figure 4: Rumen and liver fluke eggs
1.6. Treatment
All compounds for the treatment of fasciolosis are not equally effective against stages of
development of Fasciola hepatica in the body. For the treatment of acute fasciolosis, it is
essential to choose a product highly effective against the juveniles that damage the liver
parenchyma. For chronic disease a compound active against adult fluke is required (Radostits et
al., 2007).Triclabendazole (Fasinex) is considered as the most common drug due to its high
efficacy against adult as well juvenile flukes. It is effective against adult Fasciola hepatica at a
dose rate of 7.5 mg/kg in sheep and 10 mg/kg in cattle. It is ovicidal and well kills any Fasciola
hepatica eggs present in the bile duct or the alimentary tract at the time of treatment. Clorsulon is
supplied in combination with ivermectin for combined fluke and around warm control in cattle.
Nitroxynil is given subcutaneously at 10 mg/kg and has good efficacy against the adult fluke but
the dose has to be increase by up to 50% to obtain adequate control of acute disease (Radostits et
al., 2007). Until recently treatment was not highly successful due to the in efficiency of the old
drugs against the early parenchymal stages; however efficient drug are now available on the
choice of triclabendazole which remove all developing stages over one week old. In cattle,
chronic form of the disease is more common and drugs like rafoxanide and nitroxynil other than
triclabendazole are more effective (Marquardt et al., 2000).

23. 16
1.7. Prevention and control
Because the infection can be difficult to detect and can be transmitted in so many ways, control
of fasciolosis has represented a significant challenge. The role of domestic and wild animal
reservoirs, coexistence of the various Fasciola and snail species, and varying types of endemic
situations have rendered the creation of a universal control strategy unrealistic (Mas-Comas
2009). The methods to control fasciolosis generally include strategic application of anthelmintics
to eliminate the parasite from the host at the most convenient time for effective prevention of
pasture contamination, reduction of the number of intermediate host snails and reduction of the
chances of infection by efficient farm and grazing management. In fact control of fasciolosis
requires intervention of relationships between the environment, ruminant hosts and snail hosts,
the parasite life cycle, agricultural cycles and animal husbandry procedures. Therefore, good
understanding of the environment-host-parasite inter relationships are essential for formulating
the control measures suitable for an area (Mahato et al., 2000).
The control of the snails includes the use of organic, inorganic and plant derived molluscicides
and biological control using competitor snails (Marisa cornuarietis), predators of snail
(crustaceans, amphibians, reptiles, free-ranging ducks or geese and rodents.) and commensals
(Sara, 2013). Drainage is the one permanent way to control or eliminate the mollusks (Mas-
Coma et al., 2005). Control of snail by chemical such as niclosamide, copper sulphate, sodium
penta chlorophenate focally and seasonally possible, however, usually not practical due to labor,
high cost, environmental consideration and rapid colonization of snail habitats (Ahmed,
2009).The seasonal strategic application of effective anthelmintics which is specific for
trematode as well as timely prophylactic and curative treatment play an important role in the
control of liver fluke infection (Wakuma, 2009).
A commercial vaccine to prevent fasciolosis is currently not available (McManus and Dalton,
2006). However, immunoprophylactic control of fasciolosis has been attempted in both sheep
and cattle using injection with either parasite extracts or defined functional parasite antigens
which differ in protection level elicited (McDougall, 2012). These antigens include glutathione
Stransferase (Purified from adult Fasciola hepatica), cathepsin L-like cysteine proteases
(Cysteine endopeptidases are found in many parasitic worms, with an important role in
host/parasite interactions), fatty acid binding protein ( the first defined and purified antigen

24. 17
fraction to be tested as a vaccine against fasciolosis and it is a set of proteins purified from an
extract of adult Fasciola hepatica), leucine aminopeptidases ( the removal of amino acids from
the N-termini of peptides and proteins from human blood fluke, S. mansoni ) and fluke
hemoglobin(isolated from Fasciola hepatica) (McDougall, 2012).Vaccine against fasciolosis is
under development. One of these which use recombinant fluke cathepsin L proteinase has given
up to 79% protection against infection in cattle and sheep (Robinson et al., 2009).
Human fasciolosis can be prevented by not eating raw watercress, lettuce and other
metacercariae-carrying aquatic plants of wild or unknown source. These vegetables have to be
produced in controlled conditions, away from animals and fecal contamination as well as snails
(Mas-Coma et al., 2005).

25. 18
2. IMPORTANCE OF FASCIOLOSIS
2.1. Economic importance
Fasciolosis is considered as important limiting factor for bovine and ovine production.
Fasciolosis imposes direct and indirect economic impact on livestock production, particularly of
cattle and sheep. Both Fasciola hepatica (high land) and Fasciola gigantic (low land) type of
liver flukes cause severe losses in Ethiopia where suitable ecological conditions for the growth
and multiplication of intermediate host snails are available (Addiss et al., 2015). Economic
impact of fasciolosis on livestock is enormous and great loses are evident especially where
farmers have little or no knowledge on the disease. Loses are more encountered during raining
season when most stocks are exposed to fluke challenge (Ekenma, 2015). In Ethiopia, the
economic loss caused by bovine fasciolosis due to decreased productivity alone was estimated to
350 million birr per annum (Manyazewal et al., 2014).
Important direct economic losses associated with fasciolosis includes host mortality, liver
condemnation at abattoirs, lower production of meat and milk; reduced weight gain, lower calf
birth weight, reduced growth in effected animals and impaired fertility. The value of the losses
resulting from this disease runs into millions of dollar. However, the estimation of economic
losses due to fasciolosis at national and regional level is limited by lack of accurate estimation of
prevalence of the disease (Oladele and IA, 2014). Apart from indirect economic losses associated
with the disease, other non-quantifiable losses are also experienced. For instance, liver is
generally regarded as a delicacy in money countries, usually in high demand. This makes
condemnation during post-mortem inspection a problem as butchers and meat traders hide their
meats from inspectors or even refuse inspection. Others are: death of unknown number of
animals (including the under-aged) due to acute fasciolosis (Manyazewal et al., 2014).
Indirect losses associated with fasciolosis includes great expenses on anthelmintics for treatment,
an additional cost of control in terms of medication costs, veterinary fees, and labour costs aimed
at reducing parasitism, metabolic diseases, exposure of animals to other diseases due to
secondary complications (Oladele and IA, 2014, Ekenma, 2015).

26. 19
Table 3: The total annual economic losses encountered due to condemnation of infected liver in
different abattoirs and slaughter houses of Ethiopia
Municipal abattoir/
Slaughter houses
Annual losses in ETB Reference(source)
Adwa municipal abattoir 88,813.6 (Ibrahim et al., 2009
Assela municipal abattoir 698,700.6 (Yitagezu et al., 2015)
Bedele,municipal abattoir 28,360.6 (shiferaw et al., 2011)
Dembi Dolo town 63,504 (Addis Getu et al., 2015)
Haramaya municipal abattoir 83,875.9 (Yesufe et al., 2016)
Kombolcha municipal abattoir 34,827 (Bekele et al., 2010)
Mekelle municipal abattoir 122, 414.47 (ashenafi et al., 2016)
Nekemte town 63,072 (Petros, 2013).
Wolaita Soddo town 334,950 (Negesse , 2014)
2.2. Public health importance
Bovine fascioliasis accounts for the majority of transmissions and are evenly spread around the
world causing 29% of zoonoses (Jones et al., 2008). Human Fasciolosis has been reported from
countries in Europe, America, Asia, Africa and Oceania. The incidence of human case has been
increasing in the 51 countries of 5 continents. A person must ingest the metacercariae to become
infected. About 2.4 million people are infected world wide and 180 million are at risk of the
infection. In Africa, the infection has been found to be a serious problem in humid and sub-
humid zones (Ekenma, 2015).
Human acquire infection through ingestion of metacercariae that are attached to certain aquatic
plant and vegetable. In addition experimental studies suggested that human consuming raw liver
dish from liver infected with juvenile flukes could become infected (Mihret et al., 2015). The
distribution of the disease is predominantly rural being associated with cattle and sheep breeding.
The degree of pathogen city of Fasciola hepatica to man depends on many factors; particularly
the number of snails present and the origin infected mechanical and toxic damage are
characteristics (Assefa, 2005). Control of human fasciolosis depends on reducing infection in
animals and preventing the contamination of edible aquatic plants with infective metacercariae
(Robinson and John, 2009).

27. 20
To date, the majority of reported human cases of fasciolosis are due to infections of Fasciola
hepatica. However, some reports indicate a rise in human infections due to Fasciola gigantica in
Vietnam (Hien et al., 2001; Mas-Coma et al., 2005). Few human deaths have been attributed to
fasciolosis; cases that do prove fatal usually involve complications such as ulceration of the bile
duct and acute haematobilia or very high levels (more than 40 adult flukes) of chronic infection
(Robinson and John, 2009).

28. 21
3. STATUS OF BOVINE FASCIOLOSIS IN ETHIOPIA
Various reports indicated that, Ethiopia is one of the countries with suitable climatic condition
for the existence of fasciolosis. The presence of fasciolosis due to Fasciola hepatica and
Fasciola gigantica in Ethiopia has long been known and its prevalence and economic
significance has been reported by several researchers Different researchers so far conducted in
Ethiopia reported variable prevalence rates of bovine fasciolosis in different localities of the
country (Tilahun et al., 2006; Tolosa and Tigre, 2007; Fufa et al., 2009; Gebretsadik et al., 2009;
Rahmeto et al., 2010).
In Ethiopia both Fasciola hepatica and Fasciola gigantica have the greatest risk occurred in
areas of extended high annual rainfall associated with high soil moisture and surplus water, with
risk diminishing in areas of shorter wet season and or lower temperatures (Mohammed et al.,
2016), but Fasciola hepatica was shown to be the most important fluke species in Ethiopian
livestock with distribution over three quarter of the nation except in the arid north-east and east
of the county. The distribution of Fasciola gigantica is mainly localized in the western humid
zone of the country that encompasses approximately one fourth of the nation (Girmay et al.,
2015). In our country the prevalence of bovine fasciolosis has shown to range from 11.5% to
87% (Ibrahim et al., 2009, Tilahun et al., 2006; Fufa et al., 2009; Berihun, 2012 and Mihretab et
al., 2010).
Table 4: Prevalence of fasciolosis in different areas of Ethiopia on bovine
Sites of study Prevalence of disease (%) Survey method
Gondar 83.88 Coprology
Tigray 26 Abattoir
Gojjam 61.97 Abattoir
Wollo 15.77 Coprology
Wollega 18.99 Coprology
Harerge 14.8 Abattoir
Badale 20.8 Coprology
Source: (Mihret et al., 2015)

29. 22
4. CONCLUSION AND RECOMMENDATIONS
In general, it can be concluded that Fasciolosis is one of the major factors for livestock
production in by inflecting direct and indirect loss at different parts of the country. It can causes
severe liver damage and increases the susceptibility of cattle to secondary bacterial infections,
liver condemnation, production loss, failure to gain weight in young animals and weight losses in
older animals. The two species of the greatest veterinary importance are Fasciola hepatica and
Fasciola gigantica and snails are their intermediate host.The fluke has worldwide distribution
occurs in areas where cattle and sheep are raised and wait land area where a niche for Lymnaeid
snail. Mostly in developing countries including Ethiopia, cattle management systems are
extensively rearing which make the animal to be easily exposed to the disease. Deworming and
training on improved husbandry/management practices lower bovine Fasciolosis prevalence in
cattle. Fasciolosis is now recognized as an emerging zoonotic disease.
From the above conclusion the following recommendations are forwarded:-
 Standard regulations and functional meat inspection policies should be formulated for organs and
carcass approval/ rejection.
 Vegetables grown in fields should be thoroughly cooked to reduce infection of fasciolosis in
humans
 Farmers should be trained about the zoonotic and the economic impact of the disease
 Awareness of animal owner's about the disease, treatment and the control strategy
 Improving of the veterinary service and infrastructure in prevalence area with provision of
modern antihelemntics and treatment is giving based of the weight of the animal.
 Control of intermediate host snails through drainage, practicing zero grazing and also application
of molluscide drugs is important in the control of the disease
 Economic importance of the disease should be evaluated.
 Further epidemiological investigation should be encouraged

30. 23
REFERENCE
Abbot, K., Taylor, M., and Stubbings, L. (2009): Sustainable worm control for sheep 3rd Edition, A
technical manual for veterinary surgeons and advisors, Pp. 42-45.
Abdisa,T., (2017): Review on the Sheep Fasciolosis in Ethiopia, Open Access Journal of Veterinary
Science & Research, 2 : ISSN: 2474-9222.
Abunna, F., Asfaw, L., Megersa, B., & Regassa, A. (2010): Bovine fasciolosis: coprological, abattoir
survey and its economic impact due to liver condemnation at Soddo municipal abattoir, Southern
Ethiopia, Tropical Animal Health and Production, 42 (2):289-92.
Addis, G., Adina, K. and Jemberu, A. (2015): Prevalence and economic importance of bovine
fasciolosis in Dembi Dolo municipal abattoir, south-western Ethiopia, International Journal of
Agriculture and Veterinary Sciences, 1(1):33-34.
Ahmed, M., (2009): Prevalence of ovine fasciolosis in and around Kombolcha.DVM thesis FVM,
University of Gondar, and Gondar, Ethiopia.
Alasaad, S., Soriguer, R.C., Abu-madi, M., Behairy, A.E., Jowers, M.J., Díezba˜Nos, P.D., Píriz, A.,
Fickel, J. and Zhuf, X.Q. (2011): A Taq Man real-time PCR-based assay for the identification of
fasciola spp. Veterinary Parasitology, 179 (13): 266 – 271.
Ali L, Chen M, Alasaad S, Elsheikha M, Li J, Li H, Li R , Zou F, Zhu X and Chen J. (2011): Genetic
characterization, species differentiation and detection of Fasciola spp. by molecular approaches,
parasite and vectors, 4: 101.
Ashenafi K, Alemu A, Hagos A, Biniam T and Aklilu F, (2016): The Prevalence and Economic Impact
of Bovine Fasciolosis in Mekelle Municipal Abattoir, Open Access Journal of Veterinary
Science & Research, 1(4).
Asressa Y., Hassen K.,Tewodros F., and Mersha C. (2012): Prevalence of cattle flukes infection at
Andassa Livestock Research Center in north-west of Ethiopia, Veterinary Research Forum 3(2).
Assefa, M., (2005): Parasitic Causes of Carcass or Organ Condemnation at Assela Municipality Abattoir.
Ph.D. Thesis, Faculty of veterinary Medicine, Addis Ababa University, Debre Zeit.
Janneh B., (2016): Factors associated with bovine fasciolosis in kponekantamanso District, greater-accra
region, 2015-2016, school of public health,College of health sciences Universty of ghana, legon.
Bekele, M., Tesfay, H. and Getachew,Y. (2010): Bovine fasciolosis: Prevalence and its economic loss
due to liver condemnation at Adwa municipal abattoir, North Ethiopia. Ethiopian Journal of
applied science and technology, 1(1): 39-47

31. 24
Belay, E., Wassie, M. & Abadi, A. (2012): Prevalence and Economic Losses of Bovine Fasciolosis in
Dessie Municipal Abattoir, South Wollo Zone, Ethiopia. European Journal of Biological
Sciences 4 (2), 53-59.
Bemrew, A., Anmaw, S. and Gebretsadik, K. (2015): A Review on Bovine Fasciolosis, European
Journal of Biological Sciences 7 (3), 139-146.
Berihun A, (2012): Prevalence of bovine fascilosis in municipal Abbatoir of Adigrat, Tigray, Ethiopia,
13 (9), 1695-7504.
Bio Ventures for Global Health, (2015): Available at: (www.bvgh.org/Current-Programs/Neglected-
Disease-Product-Pipelines/Global-Health-Primer/Diseases/cid/View Details/ItemID/23.aspx).
Boray, C., (2007): Liver Fluke Disease in Sheep and Cattle.NSW Department of Primary Industries.
CDC, (2013): "Parasites – Fascioliasis (Fasciola Infection)". www.Cdc.gov
CDC, (2016): Prevention and Fasciola –Biology, www.cdc.gov.
Conceiçao, M.A., Durao, R.M., Costa, I.H., Correia da Costa, J.M. (2002): Evaluation of a simple
sedimentation method (modified McMaster) for diagnosis of bovine fasciolosis, Veterinary.
Parasitology, 105: 337-343.
CSA (Central Statistical Agency), (2013): The Federal democratic republic of Ethiopia central statistical
agency, agriculture in figure key finding of the 2010/11-2012/13 agricultural surveys for all
sectors and seasons’ country summary, FDRE, CSA Addis Ababa, Ethiopia, 2.
Dalton J., Neill, S., Stack, C., Collins, P., Walshe, A., Sekiya, M., Doyle, S., Mulcahy, G., Hoyle, D.,
Khaznadji, E., Moirq, N., Brennan, G., Mousley, A., Kreshchenko, N., Maule, A., and Donnelly,
S. (2003): Fasciola hepatica cathepsin L-like proteases: biology, function, and potential in the
development of first generation liver fluke vaccines. International Journal for Parasitology, 33:
1173-1181.
De Bont, J., Claerebout, E., Riveau, G., Schacht, A., Smets, K.,Conder, G.,Brake, D., Capron, A.,
Vercruysse, J. (2003): Failure of a recombinant Schistosoma bovis-derived glutathione S
transferase to protect cattle against experimental Fasciola hepatica infection, Veterinary.
Parasitology, 113: 135–144.
Dechasa, T., Antench W. and Dechasa, F. (2012): Prevalence, Gross Pathological Lesion and Economic
Losses of Bovine Fasciolosis at Jimma Municipal abattoir, Ethiopia. Journal of Veterinary
Medicine and Animal Health, 4 (1): 6-11.
Dong, A. I., Zhang, S. J., Elsheikha, W. Y., Mahmmod, H. M., Lin, Y. S., Yuan, R. Q., Shi, Z. G.,
Huang, Y. and Zhu, X. Q. (2010): Specific PCR based assays for the identification of fasciola
species: their development, evaluation and potential usefulness in prevalence surveys, Annals of
Tropical and Medical Parasitology, 104: 65-72.

32. 25
Ekenma K., (2015): Bovine Fascioliasis, a Review, Journal of Agriculture and Veterinary Science
(IOSR-JAVS), 8: 23-26.
Fufa A, Loma A, Bekele M, Alemayehu R. (2009). Bovine fasciolosis: Carpological, abattoir survey and
its economic impact due to liver condemnation at Soddomunicipal abattoir, Southern Ethiopia.
Tropical Animal Health and Production, 42: 289-292.
Gebretsadik B, Gebrehiwot,T.,Habtom K, Negus A. (2009): Prevalence and economic significance of
fasciolosis in cattle in Mekelle area of Ethiopia Tropical Animal Health and Production, 41:
1503-1504.
Giang Thanh, N., (2012), Zoonotic fasciolosis in Vietnam: molecular identification and geographical
distribution, Laboratory of Parasitology Department of Virology, Parasitology and Immunology
Faculty of Veterinary Medicine, Ghent University Salisburylaan 133: 1-43.
Girmay T., Teshome Z. and Hailemikael A. (2015),Prevalence and Economic Losses of Bovine
Fasciolosis at Hawzien Abattoir, Tigray Region, Northern Ethiopia, journal of veterinary
advances, 5(5): 945-951.
Hien T. V., Dung T. T. K., Chi N. H., Dahn P. H., Pham P. T. (2001): Fasciolosis in Vietnam. Southeast
Asian, Journal of Tropical Medicine and Public Health, 32: 48–50.
Hunter G., Strickland G., Magill A. (2000): Hunter’s tropical medicine and emerging infectious diseases,
8th
Ed.
Ibrahim,N., Wasihun,P. and Tolosa T. (2009): Prevalence Of Bovine Fasciolosis And Economic
Importance Due To Liver Condemnation At Kombolcha Industrial Abattoir, Ethiopia, The
Internet Journal of Veterinary Medicine. 8: Pp.1
ILRI, (2009): Management of vertisols in Sub-Saharan Africa, Proceedings of a Conference Postmortem
differential parasite counts FAO corporate document repository. In J.P. Dalton (Ed.), Fasciolosis,
Wallingford, UK: CABI Publishing.Pp.31-46.
Jemal, T. (2009): Major Causes of Organ Condemnation in Cattle Slaughter at Kombolcha ELFORA
Meat Factory Abattoir South Wollo, DVM Thesis, Haramaya University, Ethiopia.
Jones, K., Patel N., Levy M., Storeygard A., Balk D., Gittleman J., Daszak P., (2008): “Global trends in
emerging infectious diseases,” Nature, 451: issue 06536.
Kahn, C.M. (2005): The Merck veterinary manual, 10th
Ed. New Jersey, USA: Merck & Company,
Incorporation, Whitehouse Station, Pp. 273-1036.
Kaplan, M., (2001): Fasciola hepatica: A Review of the Economic Impact in Cattle and Considerations
for Control, Veterinary Therapeutics 2(1).
Khaled, S., Desoukey, M., Elsiefy and N., Elbahy, (2010): An Abattoir Study on the Prevalence of Some
Gastrointestinal Helminths of Sheep in Gharbia Governorate, Egypt. GlobalVeterinaria, 5: 84-87.

33. 26
Khan, E.M., (2005): The Merck Veterinary Manual. 9th
21.Ed. USA: Merck Inc.Pp.269.
Lora R. Ballweber. (2016): Merck Veterinary Manual, Fasciola hepatica in Ruminants (Common liver
fluke).
Mahato, N., Harrison, S. and Hammond, A. (2000): Over view of Fasciolosis, An economically
important disease of livestock in Nepal, Fasciolosis ~Nepal.
Manyazewal , A., Mengistu, G., Tsegaye ,T.(2014): Economic Significance of Fasciolosis at Mettu
Municipal Abattoir, Southwest Ethiopia, Journal of Advanced Veterinary Research, 4: 53-59.
Maqbool, A., Hayat, C., Tanveer, A. and Hashmi, H. (2002): Epidemiology of Fasciolosis in Buffaloes
under Different Management Conditions, Veterinary ski Arhiv, 72: 221-228.
Marquardt, W., R. Demaree and R. Grieve. (2000): Parasitology and Vector Biology, 2 ed. London
Harcourt Academic press Pp. 273-279.
Martínez-Valladares, M., Cordero-Pérez, C., Castañón-Ordóñez, L., Famularo, M.R., Fernández-Pato, N.
and Rojo-Vázquez, F.A. (2010): Efficacy of triclabendazole oral formulation against mixed
infections of Fasciola hepatica and gastrointestinal nematodes in sheep. Veterinary Parasitology,
174: 166-169
Mas -Coma, S.,Bargues, M. , & Valero, M. (2005): Fascioliasis and other plant-borne trematodes
zoonoses. International Journal for Parasitology, 35 (11): 1255-1278.
Mas-Comas, (2009): Chapter 2.Fasciola, Lymnaeids and human Fascioliasis, with a global overview on
disease transmission, epidemiology, evolutionary genetics, molecular epidemiology and
control .Advanced Parasitology, Pp. 69.
McDougall, H., (2012): Identifying “hidden” antigens in the liver fluke, Fasciola hepatica. PhD thesis at:
(http://theses.gla.ac.uk/3661/).
McManus D. and Dalton, J. (2006): Vaccines against the zoonotic trematodes Schistosoma japonicum,
Fasciola hepatica and Fasciola gigantica Parasitology. Pp.133
Mezo M., González-Warleta, J., Castro-Hermida, L. Mui˜no and F.M. Ubeira, (2010): Field evaluation
of the MM3-SERO ELISA for detection of anti-Fasciola IgG antibodies in milk samples from
individual cows and bulk milk tanks, Parasitology. International, 59: 610–615.
Mezo M., M. González-Warleta, J. Castro-Hermida, C. Carro and F. Ubeira, (2009): Kinetics of anti-
Fasciola IgG antibodies in serum and milk from dairy cows during lactation, and in serum from
calves after feeding colostrum from infected dams. Veterinary Parasitology, 168: 36–44.
Michael, A. (2004): Infectious prevalence of ovine Fasciolosis in irrigation schemes along the upper
Awash River Basin and effect of strategic anthelmintic treatment in selected up stream areas.
MSC thesis, Addis Ababa University, school of Graduate studies, Department of Biology, Addis
Ababa, Ethiopia.

34. 27
Mihret, T., Samuel, D. and Addis, G. (2015): A Review on Ruminant Fasciolosis, Open Access Library
Journal, 2: 1655.
Mihretab B, Haftom T, Yehenew G. (2010): Bovine fasciolosis: Prevalence and its economic loss due to
liver condemnation at Adwa municipal abattoir, North Ethiopia. Ethiopian, Journal of
Agricultural Science and Technology, 1: 39-47.
Mitchell, G. (2003): Treatment and Control of liver fluke in sheep and cattle. Technical notes November,
Sac 2003.West mains roads, Edinburgh.
Mochankana, M. (2014): Epidemiological studies on bovine fasciolosis in Botswana, degree of Doctor
of Philosophy thesis, Murdoch University. College of Veterinary Medicine and School of
Veterinary and Life Sciences ,Murdoch University Perth, Western Australia.
Mohammed, Y., Nuraddis, I., Wubit, T., and Yosef, D. (2016): Prevalence of Bovine Fasciolosis in
Municipal Abattoir of Haramaya, Ethiopia, Jimma University, School of Veterinary Medicine.at :
(www.iiste.org).
Mugugeta, S., Begna, F. and Tsegaye, E. (2011): Prevalence of Bovine Fasciolosis and Economic
Significance in and Around Assela, Global Journal of Medical Research, 11, ISSN 0975-5888.
NADIS, (2012), liver fluke control in cattle, Available at: (http://www.nadis.org.uk/bulletins/liver-fluke-
control-in-cattle.aspx).
Negesse, M. A. and Mohammed, G.A. (2014): Bovine Fasciolosis, Prevalence and Economic
Significance in Southern Ethiopia, Haramaya University, College of Veterinary Medicine, Dire
Dawa Wolaita Soddo, Ethiopia.
Oladele-Bukola MO and IA Odetokun, (2014): prevalence of bovine fasciolosis at the ibadan municipal
abattoir, Nigeria, African journal of food agriculture, nutrition and development .14(4): 9055-
9070.
Ozung, P.O., Owai, P.u. and Oni, K.O. (2011): An Assessment of the Prevalence of Fascioliasis of
Ruminants in Ikom Abattoir of Cross River State, Nigeria. Continental Journal of Veterinary
Sciences, 5 (1): 1-5.
Parida, M., Sannarangaiah, S., Dash, PK., Rao, PV. and Morita, K. (2008): Loop mediated isothermal
amplification (LAMP): a new generation of innovative gene amplification technique;
perspectives in clinical diagnosis of Amazônia Brasileira. Journal of the Brazilian Society of
Tropical Medicine, 41(4): 381-385.
Petros A, Addisu K. and Amanuel, W, (2013): Prevalence and economic significance of bovine
fasciolosis in Nekemte Municipal abattoir, Journal of veterinary medicine and animal health,
5(8): 202-205.

35. 28
Radostits, O.M., Gay, C.C., Hinchclitt, K.W. and Constable, P.D. (2007): Veterinary Medicine, a Text
Book of the Disease of Cattle, Horses, Sheep, Goats, and Pigs. 10th Edition, Elsevier, New York,
Pp. 1516-1579.
Rahmeto A, Fufa A, Mulugeta B, Solomon M, Bekele M,Alemayehu R. (2010): Fasciolosis: Prevalence,
financial losses due to liver condemnation and evaluation of a simple sedimentation diagnostic
technique in cattle slaughtered at Hawassa municipal abattoir, southern Ethiopia. Ethiopian,
Journal of veterinary science, 14: 39-51.
Rapsch, C., Schweizer, G.,Grimm F., Kohler, L., Deplazes, P., Braun, U., Torgerson, P. R. (2006):
Estimating the true prevalence of Fasciola hepatica in cattle slaughtered in Switzerland in the
absence of an absolute diagnostic test. International Journal of Parasitology, 36: 1153-1158.
Robinson, M. W. and Dalton, J. P. (2009): philosophical transaction of royal society, B Zoonotic
helminthes infections with particular emphasis on fasciolosis and other trematodiases, 364:
2763–2776.
Robinson, M. W., Menon, R., Donnelly, S. M., Dalton, J. P., and Ranganathan, S. (2009): An Integrated
Transcriptomics and Proteomics Analysis of the Secretome of the Helminth Pathogen Fasciola
hepatica Proteins associated with invasion and infection of the mammalian host. Molecular &
Cellular Proteomics, 8(8): 1891-1907.
Rokni, M., Massoud, J. and Kia, E. (2003): Comparison of Adult Somatic and Cysteine Proteinase
Antigens of Fasciolagigantica in Enzyme Linked Immunosorbent Assay for Diagnosis of Bovine
Fasciolosis. DIE Seminar on Biotechnology, Tehran. Pp. 9-13.
Sara. d.S. L.C. (2013): Pilot study on Bovine Fasciolosis in Praia slaughterhouse in Santiago, Cape
Verde, Universidade de Trás-os-Montes e Alto Douro, Dissertação de Mestrado em Medicina
Veterinarian.
Saria, (2011): an Epidemiological Study of Bovine Fasciolosis in Pothar Region, Pakistan. Department
of zoology Faculty of Sciences Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi
Pakistan
Sheama, S., Khalid, T. and Luma, H. (2010): The Presence of Fasciola hepatica (Liver-fluke) in Human
and Farm animal (sheep, goats&cattle) in Al Diwaniya province, Wasit uni/college of medicine.
Shiferaw M., Feyisa B. and Ephrem T. (2011): Prevalence of Bovine Fasciolosis and its Economic
Significance in and around Assela, Ethiopia, global journal of medical research, 11: 1-8.
Tadele, T. and Worku, T. (2007): the Prevalence and Economic Significance of Bovine Fasciolosis at
Jimma, Abattoir, Ethiopia, Jimma University, College of Agriculture and Veterinary Medicine,
Jimma, Ethiopia.

36. 29
Taylor M., R Coop and R. Wall. (2007): FVM, Veterinary Parasitology. 3rd ed. Oxford: Blackwell
Publishing, Pp. 85-87.
Terefe, D., Wondimu, A. and Gachen, D.F. (2012): Prevalence, gross pathological lesions and economic
losses of bovine Fasciolosis at Jimma Municipal Abattoir, Ethiopia. Journal of Veterinary
Medicine and Animal Health, 4(1): 6-11.
Tilahun, G., Tesfu K., Berhanu E, Legesse W, Ahmed A, Nega B, and Girmay M. (2006): Pilot control
of fasciolosis and related animal fluke infections by the use of Endod and reduced morbidity: In
pre-intervention studies. Ethiopian, Journal of Veterinary Science, 10: 67-70.
Tolosa T, Tigre W. (2007): Prevalence and economic significance of bovine fasciolosis at Jimma
abattoir, Ethiopia. International Journal of Veterinary Medicine 3: 212-219.
Valero, A. and Mas-Com, S. (2000): Comparative infectivity of Fasciola hepatica metacercariae from
isolates of the main and secondary reservoir animal host species in the Bolivian Altiplano high
human endemic region, Department of Parasitology, Faculty of Pharmacy, University of
Valencia, Valencia, Spain, folia parasitologica 47: 17-22.
Valero M, Darce N, Panova M, Mas-Coma S. (2001): Relationships between host species and
morphometric patterns in Fasciola hepatica adults and eggs from the northern Bolivian Altiplano
hyperendemic region. Veterinary Parasitology 102(2): 85-100.
Wakuma, M., (2009): Prevalence and Economic Significance of Bovine Fasciolosis at Bedele Municipal
Abattoir. PhD Thesis, Faculty of Veterinary Medicine, Jimma University, Jimma.
Woldemariam, S. and Wossene, A. (2007): Effects of a strategic anthelmintic treatment intervention
bovine Fasciolosis: A study conducted in facilities endemic area in north western Ethiopia,
Ethiopian Veterinary Journal, 11(2): 59-68.
Yitagezu, A., Tefera, W. and Mahendra, P. (2015): prevalence of bovine fasciolosis and its economic
impact in Bedele, Ethiopia, school of veterinary medicine, Hawassa University, Hawassa,
Ethiopia. Haryana Veterinary (54 (1): 7-10.
Yusufe, M., Ibrahim, N., Tafese, W. and Deneke, Y. (2016): Prevalence of bovine fasciolosis in
municipal abattoir of Haramaya, Ethiopia. Food Science and Quality Management, 8: Pp 38

37. APPROVAL SHEET
This seminal paper ‘‘Review on bovine fasciolosis and its importance” for presentation with my
approval as academic advisor
Advisor’s name: Dr. Biyansa Adugna (DVM)
Signature……………………………………………….
Date of submission………………………………………