The study of animal viruses is important from a veterinary viewpoint and many of these viruses causes diseases that are economically devastating. Many animal viruses are also important from a human medical perspective. The emergence of the SARS virus in the human population, coming from an animal source, highlights the importance of animals in harbouring infectious agents; avian influenza viruses can directly infect humans. In addition research into animal viruses has made an important contribution to our understanding of viruses in general, their replication, molecular biology, evolution and interaction with the host.

1. WELCOME
• MD. Rafiqul Islam
• Level : 2, Semester: 2
• ID : 1501171
• Bangladesh Agricultural University
• Mymensingh - 2202

2. NDV
Family: Paramyxoviridae Genus: Paramyxovirus
Properties:
-Size : 100-250nm & diameter: 18nm
-Haemagglutinin & Neuraminidase present
-Inactivated at 55 “ in 5 min & direct sunlight in 30 min
-Infective at 4”(few days), at -20”(few weeks)
& at -70(few months to years)
-Inactivated by 2-3% phenol /cresol & 0.1% formalin in 6 hrs
Strains:
1) Avirulent: V4, MC110, Ulster 2C
2) Lentogenic: Hitcher B1, La Sota, Clone 30
3) Mesogenic: Roakin, Kumarov, Mukteswar
4) Velogenic: Neurotropic- Texas GB
Viscerotropic: Hert”s 33, CA 2089/72
Clinical signs:
-Egg production drops , Edema of head (eye), Greenish dark
watery diarrhoea, Respiratory & Neurological problems
Transmission:
-Directly/indirectly(inhalation of dust), contaminated feed, water,
instrument, cloth,
Respiratory exudate,feces
Sample:
-
Cultivation:
-10-12 days chicken embryonated eggs in CAM (death in 24-72
hrs causing haemorrhagic leisons & encephalitis)
-Chick embryo fibroblast/kidney cell culture
-Baby hamster kidney monolayer cell culture
Tests:- HA test, HI test, SNT, ELISA
Vaccine: Live lentogenic -BCRDV (F strain) !st in 5-7 days & 2nd at
21 days intranasal/occular, Live mesogenic(as booster)- LRI-M &
BAU-K strains 1ml after 2 month of age through IM
Killed vaccine: Fowl-0.5ml,Turkey-0.5-1 ml IM/SC.Booster dose at
16-20 week old at 6-12 month interval.
PPR
Family: Paramyxoviridae
Genus: Morbillivirus
Properties:
-Size: 150-300nm
-ssRNA
-Enveloped
-Helical, filamentous
-Ether & heat sensitive
-8 proteis- N P(V,C),F,H,M,L
Nature: Fever
,stomatitis,enteritis, pneumonia ,
death
-Affinity for lymphoid organ and
GIT
-All strains are similiar and gives
cross protection
Clinical sign: Jebra stripping
3 phases:
Acute-Pneumonia and profuse
diarrhoea in goat
Peracute
Subacute-sheep
Transmission:
Tear, nasal discharge, sputum,
diarrhoeic feces
Sample:
Lymphoid organ,nasal
swab,diarrhoeic feces
Culture:
-Goat,sheep kidney cell cult.
-Vero cell line
Serological tests:
ELISA*, NT
Canine Distemper
Family: Paramyxoviridae
Genus: Morbillivirus( All 4 strains are
antigenically similar)
Properties:
-Size: 90-250
-Inactivated by lipid solvents, .1%
formalin/ 1% lysol
-Haemagglutinate chicken &
guineapig RBC
-Survives at 55” for 30 min
Clinical signs:
-Depression, loss of weight,
dehydration, hyper keratosis of foot
pad,muscle spasm
Transmission:
-Direct contact or by aerosol/droplet
Sample:
Cultivation:
-Intact host: Unweaned mice, baby
hamster, rabbits(increase virulence)
-Primary/continuous cell cultures of
dog or ferret kidney cells
-Egg adapted strains grow well in
chicken embryo cell culture
-Form CPE by granular degeneration
& vacuolation of cells with giant cell &
syncytia formation ,occasionally
nuclear inclusion bodies
Serological tests:
-AGID, CFT, ELISA, IIFT

3. FMD
Family: Picornaviridae
Genus: Aphthovirus
Properties:
-30 nm diameter, MW- 2.5 * 106
- (+) ve sense ssRNA
-Non enveloped, Icosahedral symmetry,spherical shape
-4 proteins: VP-1,2,3,4
-Remain infective for 3 days in summer & 28 days in winter
-7 serotypes: O (11),A (32) ,C ASIA-1 (3),SAT( south African Territory)-
1(7),2 (3),3 (4)
-Morbidity: 100%
-Mortality: 1% in large animal,
50% in calf
Transmission:
-Direct contact ,aerosol(upto 60 km) ,meat, milk ,semen
Sample:
Vesicular fluid, tongue epi. ,skin from inter digital space, saliva
Cultivation:
-Goat ,calf, lamb, pig kidney cell culture
-BHK-21 cell line
-Produce rounded foci, pyknotic,refractile cell withun cytoplasm
Animal inoculation:
Guneapig: hyperkeratinized foot pad (like canine distemper)
-2-7 days old mice: intraperitoneal /intramuscular inoculation cause
paralysis & death
Serological tests:
CFT, NT, ELISA
Molecular test:
RT-PCR
Vaccine:
Trivalent vaccine in BD against O , A , ASIA_1
Duck Viral Hepatitis
Family: Picornaviridae
Genus: Enterovirus
Properties:
-ssRNA , Non enveloped
-20-40nm
-Heat & PH(3) stable
-Resistant to ether & chloroform
-3 serotypes: DHV_1,2,3
Host: Young ducklings (below 6 weeks)
Clinical signs:
Stop moving, squat down, ataxia, loss of balance, fall on side
-After death: opisthotonos position ( chest forward ,head & beak
upward and leg backward)
Transmission:
- Feces(remain viable for long period)
Sample:
- Blood, feces, liver
Isolation: Allantoic cavity
-Duck embryo: (10-14 days old)-death in 24-72 hours
-Chicken embryo: (8-10 days)-pale greenish allantoic fluid
-Chicken: for attenuation( yellow liver)
Duckling:
-1-7 day old through IM/SC (death in 24 hrs of inoculation)
Cell culture:
- Duck embryo kidney/liver cell culture (CPE characterized by rounded
necrosed cells)
Serological tests:
-AGID, ELISA, NT
Vaccine:
-Live avirulent type-1 DHV after 80 passage
-Immunization of parent stock

4. Marek”s Disease
Family: Herpesviridae , Subfamily: Gamma-herpesvirinae
Genus: Thelalymphocryptovirus
Properties:
-Size: 150-200nm
-dsDNA, Enveloped , Icosahedral symmetry
- 3 serotypes: 1 (pathogenic), 2 , 3
Host:
-Chicken mainly but turkey,duck,quail can also affected in 12-24 weeks age (
chickens of 6 week age can also be affected)
Clinical signs:
-Acute form: Diffuse lymphomatous involvement of liver,spleen ,lung,
brain, kidney, heart, gonads & around feather follicle. Enlarged
peripheral nerves
-Classical form: Partial/complete paralysis of legs & wings. Thickening
of brachial, sciatic, celiac plexus & vagus nerve ( become
yellowish/grayish, edematous, loss of striation)
Transmission:
-Direct/indirect contact (airborne route)
Sample:
-Cell associated: Buffy coat of blood, kidney, spleen,solid tumors
-Cell free: Feather tips
Cultivation:
1)Chicken embryo:
-Cell associated- 4 day old embryonated egg through yolk sac route(pock in
CAM in 18 days of inoculation)
-Cell free: 9-12 day embryos through IV route ( pock in 7 CAM days)
2)Chicken: 0.2 ml intra abdominally in 1 day old chick –reared 6/8
weeks – die with no gross lesion
3)Cell culture: Cell associated- Chicken/duck embryo/fibroblast cell
culture (focal lesions,plaque formation)
Cell free: Plaque formation in 6-8 days post inoculation
Serological tests:
- AGPT, IFT, ELISA, VNT
Duck Virus Enteritis
Family: Herpesviridae Subfamily: Alphaherpesviridae
Genus: Duck herpesvirus-1
Properties:
-Diameter 160-380nm, enveloped
-Sensitive to ether & chloroform
-Inactivated below pH 3 & above 10 & 56” in 30 min
-Non-haemagglutinating
Host:
-Duck, geese, swan ( Anseriformes)
Clinical signs:
-Anular ring
-Sudden, high, persistent flock mortatility
- drop egg production, nasal discharge, soiled vent, watery
diarrhea ,inppetence, extreme thirst, droopiness, ruffled
feather, ataxia
Transmission:
-Direct & indirect contact , water
Sample:
-Liver, spleen, kidney, caeca, blood
Cultivation:
1) Duck embryo: 9-12 days embryonated eggs – CAM
route – die due to extensive haemorrhage in 4-190 days of
inoculation
2) Cell culture: Duck embryo fibroblast cell culture ( CPE
characterized by pyknotic, rounded, clumped cell)
3) Ducklings: 1 day old duckling – IM inoculation – die in
10-12 days
Serological tests:
-VNT, IFT, PHA, ELISA

5. Rabies virus
Family: Rhbdoviridae
Genus: Lyssavirus
Properties:
- Filamentous, bullet shaped, enveloped
-ssRNA , MW- 3.4-4.6 * 10^6
-5 proteins(L, G [strongly antigenic], M, P, N)
Host:
-All warm blooded animal (Dog, cat, fox, jackal, cattle,wolves,wild
carnivores)
-Reservoir: Skunk, bat, raccoons
Strains: Two
1) Street rabies (3-8 weeks) 2) Fixed rabies (5-8 days)
Transmission:
-Bite,aerosol, organ donation
Pathogenesis:
Bite – bind to ach receptor-centripetally reach to CNS via axoplasm –
limbic system (furious) - Neocortex ( dumb/ paralytic form )-spread
centrifugally to different organs
Clinical signs: 3 phages[prodormal (1-3 days),hyperactive (1-4), paralytic
(1-2)]
Cultivation:
1) Intact host: 0.3-0.5 ml in white sucking mice – paralysis in 6-16 days &
death in 1-2 days after onset .
2) Tissue culture:Dog,cat, pig ,baby hamster brain tissue
(CPE, Negri bodies in the neuron of brain tissue)
3) Chicken embryo: Intracerebrally (negri body found)
Serological tests:
-Indirect FAT
Vaccine: Post exposure vaccination can be done
-Pre-exposure( killed)/ modified pasture type vaccine
-Pre-exposure live vaccine (HEP & LEP ) [BLRI produced]
-Cell ( human diploid cell) culture vaccine
Vesicular stomatitis
Family: Rhbdoviridae
Genus: Vesiculo virus
Properties:
-Rod shaped , helical symmetry
Host:
- Horse, cattle, pig
Clinical signs:
-Vsicles in tongue,mucous
membrane
-Secondarily in teat
Transmission:
-Arthropod(sand/black
flies,culicoides , mosquitoes),
contaminated fomites ,
equipment
Sample:
-Same as FMD
Cultivation:
-Allantoic/ amniotic/ yolk sac
route cultivation. Pock in CAM
route.
-Mosquito cell culture ( CPE)
-Intracerebrally in sucking mice-
death
Serological tests:
-ELISA, CFT , VNT
Molecular diagnosis:
- RT-PCR
Bovine Ephemeral Fever
Family: Rhabdoviridae
Genus: Ephemero virus
Properties:
-Bullet shaped, helical
-enveloped
- Agglutinate goose RBC
Host:
-Cattle , buffalo. Not
sheep/goat
Transmission:
-Culicinae & anophilinae
Sample:
-Citrated whole blood
Cultivation:
-BHK cell line (CPE & death)
-Brain of unweaned mice
[For attenuation] ( paralysis
& death within 2-3 days of
inoculation)
Serological tests:
-NT, CFT, Indirect FAT

6. Infectious Bronchitis
Family: Coronaviridae
Genus: Coronavirus
Properties:
-ssRNA
-80-120nm
-Spherical
-Enveloped
-Ether & heat sensitive
-5 proteins: N, E, M, S, HE
-Non haemagglutinating unless treated with
trypsin or ether
-2 strains: Connecticut,Massachusetts.Others are
Florida ,Holland, Callifornia,Georgia
Nature: Depression, gusping, coughing, sneezing
Cultivation:
-Allantoic cavity route
-CAM: No pock lesion but dwarfed & curled embryo
Transmission:
-Aerosol,contaminated water & oeganic matter
Sample:
Lung, Trachea
Cell culture:
-Monkey kidney cell culture
-Chicken embryo tissue culture
Serological tests:
-SNT, Immuno-diffusion test Direct FAT ,NT
Vaccine:
-Live attenuated ( by 25 or more passage in egg)
Mono/Bi valent vaccine
Avian Influenza
Family: Orthomyxoviridae Genus: Orthomyxo virus
Properties:
-Virion pleomorphic [Spherical (50-120nm) & Filamentous ( 20nm) diameter]
-500 distinct spike like surface projection (10-14nm from surface)
-Major G protein (HA) is interposed irregularly by cluster of NA [ Ratio: HA:NA = 4-5:1 ]
-Helical symmetry. (-)ve ssRNA, 6-8 segments, genome length: 12000-15000 nt
Host:
-Turkey, chicken, guinea fowl, quail, pheasant, geese, duck
Outbreak in BD: 21 March, 2007
Transmission:
-Direct contact, air, feces, respiratory/ocular discharge, hatching aggs, egg tray/cages,
poultry product, day old chick, market & slaughter house
Risk factors:
1)External: Migratory bird, domestic ducks, imported poultry/poultry bi products,illegal
trade, long & porous border
2)Internal: Geography/demography of BD, duck production system,live bird market &
backyard poultry
Clinical signs:
-Drop egg production, diarrhea, respiratory difficulty, edema of head,comb,wattle
Sample:
-Cloacal swab, trachea, lung, air sac, digestive tract, liver, spleen, heart, brain, blood
Cultivation:
1) Chicken embryo: 9-11 day old embryo – Allantoic sac route – incubate 3-7 days - die
within 24-72 hours of inoculation
2) Cell culture:Chicken embryo fibroblast cell culture & MDCK cell line(plaque formation)
Serological tests:
-AGDT, ELISA, HI, NT, CFT
Vaccine:
-Recombinant fowl pox vaccine cantaining H5 haemagglutining gene of avian influenza
virus is administered by eye drop/drinking water