Chicken anemia virus causes immunosuppression in chickens. It is transmitted vertically from breeders to progeny and horizontally between chickens. Clinical signs include depression, paleness, hemorrhages on the wings, and thymic atrophy. Post mortem lesions include blue discoloration of the skin from hemorrhages, especially on the wings, giving the disease its name "Blue Wing Disease". The virus impacts the poultry industry economically by reducing performance and increasing mortality from secondary infections due to immunosuppression.
Aspergillosis in Birds, Poultry Diseases Symptoms, respiratory diseases in ch...Field Vet
Original picture download here. http://www.fieldcasestudy.com
Aspergillosis in poultry is a disease that is easily encountered in the field. The disease is strongly associated with quality DOC. This disease is very acute, clinical symptoms can be observed starting on the second day, a minimum of the first week, the clinical symptoms can definitely be observed easily. There is no effective treatment, in this case, culling is the most appropriate choice. Horizontal spread of disease does not occur. If chickens (DOC) were selected and culling, the other chickens will still grow well. The important thing is prudence in the culling and selection. Because not all of the sick chickens showing clinical symptoms are severe. Chicks with mild clinical symptoms are often not observed when culling performed. Then in this chicken, an additional infection can occur in the following days.
tag
brooder pneumonia, aspergillosis in birds, aspergillosis in poultry, aspergillosis in chickens, treatments, aspergillus, symptoms, poultry diseases, diseases of poultry, avian pathology, mycosis,
Infectious laryngotracheitis (ILT) is an economically important respiratory disease of poultry. This highly contagious disease is caused by Gallid alpha herpesvirus type 1 (GaHV-1), commonly known as infectious laryngotracheitis virus (ILTV). The virus can be easily transmitted by infected birds and fomites. Lax biosecurity, transportation of infected birds, and spread of contaminated litter facilitates spread of the virus. Clinical signs of respiratory disease are not pathognomonic. Diagnosis is by real-time PCR and histopathology . Implementation of biosecurity is necessary for prevention, but vaccination is commonly used for control of the disease in endemic regions worldwide.
Fowl typhoid is a septicemic acute or chronic disease of domesticated birds.
The disease is worldwide distributed and natural outbreaks occur in chickens, turkeys, guinea fowl, peafowl, duckling and game birds such as quail, grouse and pheasant.
This can cause mortality in birds of any age.
Broiler parents and brown-shell egg layers are especially susceptible.
Fowl adenovirus: Using serology to control your flocksRafael Monleon
A presentation about Fowl Adenovirus in chickens. It provides insights on: etiology, pathology, monitoring and control among others.
Presented globally on September 9th 2014 via Watt Ag-Net Webinar by Dr. Rafael Monleon
Contact me in LinkedIn for any question: www.linkedin.com/rafaelmonleon
Hydropericardium syndrome(inclusion body hepatitis)Sumeet Jyoti
This presentation has been uploaded to share knowledge about hydropericardium syndrome. various references has been taken for this presentation and it is mainly focused in nepalese context.
Thank you!!!
Aspergillosis in Birds, Poultry Diseases Symptoms, respiratory diseases in ch...Field Vet
Original picture download here. http://www.fieldcasestudy.com
Aspergillosis in poultry is a disease that is easily encountered in the field. The disease is strongly associated with quality DOC. This disease is very acute, clinical symptoms can be observed starting on the second day, a minimum of the first week, the clinical symptoms can definitely be observed easily. There is no effective treatment, in this case, culling is the most appropriate choice. Horizontal spread of disease does not occur. If chickens (DOC) were selected and culling, the other chickens will still grow well. The important thing is prudence in the culling and selection. Because not all of the sick chickens showing clinical symptoms are severe. Chicks with mild clinical symptoms are often not observed when culling performed. Then in this chicken, an additional infection can occur in the following days.
tag
brooder pneumonia, aspergillosis in birds, aspergillosis in poultry, aspergillosis in chickens, treatments, aspergillus, symptoms, poultry diseases, diseases of poultry, avian pathology, mycosis,
Infectious laryngotracheitis (ILT) is an economically important respiratory disease of poultry. This highly contagious disease is caused by Gallid alpha herpesvirus type 1 (GaHV-1), commonly known as infectious laryngotracheitis virus (ILTV). The virus can be easily transmitted by infected birds and fomites. Lax biosecurity, transportation of infected birds, and spread of contaminated litter facilitates spread of the virus. Clinical signs of respiratory disease are not pathognomonic. Diagnosis is by real-time PCR and histopathology . Implementation of biosecurity is necessary for prevention, but vaccination is commonly used for control of the disease in endemic regions worldwide.
Fowl typhoid is a septicemic acute or chronic disease of domesticated birds.
The disease is worldwide distributed and natural outbreaks occur in chickens, turkeys, guinea fowl, peafowl, duckling and game birds such as quail, grouse and pheasant.
This can cause mortality in birds of any age.
Broiler parents and brown-shell egg layers are especially susceptible.
Fowl adenovirus: Using serology to control your flocksRafael Monleon
A presentation about Fowl Adenovirus in chickens. It provides insights on: etiology, pathology, monitoring and control among others.
Presented globally on September 9th 2014 via Watt Ag-Net Webinar by Dr. Rafael Monleon
Contact me in LinkedIn for any question: www.linkedin.com/rafaelmonleon
Hydropericardium syndrome(inclusion body hepatitis)Sumeet Jyoti
This presentation has been uploaded to share knowledge about hydropericardium syndrome. various references has been taken for this presentation and it is mainly focused in nepalese context.
Thank you!!!
An overview of Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) a...Dr.Kedar Karki
IBH/HPS is an acute infectious disease characterized by typical hydropericardium, severe anaemia, necrotic hepatitis and high mortality. In natural outbreaks, the affected birds may not exhibit any clinical signs (Jaffery, 1988) except sudden heavy mortality (Ravikumar et al., 1997). Mortality rates in various outbreaks range from 15- 60% (Asrani et al., 1997).
This color atlas of poultry diseases .This is very useful guide for poultry farmers & poultry practicing professionals.The atlas contains colour photographs demonstrating the overall pathology of birds. The book includes more than 50 diseases from avian infectious pathology and a similar number from non-infectious pathology.There are both classic and well known diseases and new and little known diseases. The book is designed for veterinarians, veterinary students, poultry farmers and poultry specialists.
To get more free guides and literature and books please visit www.growelagrovet.com
Canine parvovirus (CPV) is a highly contagious and relatively common cause of acute, infectious GI illness in young dogs. Although its exact origin is unknown, it is believed to have arisen from feline panleukopenia virus or a related parvovirus of nondomestic animals
Santa Margarita Animal Care Center treats a wide variety of pet illnesses, including canine parvovirus, or parvo. First identified in the late 1970s, parvo is a highly contagious and potentially fatal disease that most often affects puppies ages six to 20 weeks. Symptoms of parvo include depression followed by vomiting and diarrhea. Infected dogs quickly develop dehydration, electrolyte imbalance, fever, and may suffer additional complications such as septicemia and other bacterial infections.
Timely vaccinations are important for preventing parvo in puppies, along with isolation from other dogs until the vaccine schedule is complete (at around 16 weeks of age). Avoid potentially infected areas and sites containing dog fecal matter. Puppies should begin the parvo vaccine series at approximately eight weeks.
Contact a veterinarian if a puppy quickly develops vomiting and diarrhea. Dogs with parvo generally require several days of hospitalization and intensive care, and the outcome depends on the dog's age, immune capability, early detection, and treatment. Most puppies recover with prompt veterinary care. If you suspect parvo in your dog, please contact Santa Margarita Animal Care Center or your regular veterinarian.
Avian pox is a slowly developing disease of birds caused by several different strains of avipoxvirus. Avipoxvirus is a member of the Poxviridae family. A variety of birds worldwide, including upland gamebirds, songbirds, marine birds, and the parrot family can become infected.
The disease can be spread via mechanical vectors, primarily by species of mosquitoes. Transmission occurs when the mosquito feeds on an infected bird that has a viremia present or on virus-laden secretions from a pox lesion and then feeds on an uninfected bird.
More Original pictures of Poultry Diseases, go to http://www.fieldcasestudy.com
Infectious laryngotracheitis (ILT) is an acute, highly contagious infection of chickens and pheasants.
Inflammation of the larynx and trachea.
Result in severe production losses due to mortality and/or decreased egg production
Severe epizootic forms of infection are characterized by signs of respiratory depression, gasping (agonal respiration), expectoration of bloody mucus and high mortality
Mild forms of infection manifest variously as mucoid tracheitis, sinusitis, conjunctivitis and low mortality
Newcastle disease (ND) is a viral disease affecting wild and
domestic birds. It is characterized by a high variability in
morbidity, mortality,
ND primarily affects chickens and turkeys, but most poultry
and many wild and domestic birds are susceptible.
This manual is a brief guide to preventing, diagnosing and controlling poultry diseases. All major poultry diseases are discussed in detail. The description of each disease includes information about its cause, the susceptibility of poultry species, ways the disease is transmitted, clinical signs and lesions, how the disease is diagnosed, and ways to treat it. There are colour photos to aid in disease identification. There is additional information on the nature and cause of disease and on sanitation practices, and a glossary of common terms. The book is fully indexed so that diseases can be found by both their formal and common names
البوست ده عمل خيري ...
دي لينكات لمحاضرات في امراض وادوية الدواجن وكورسات التنمية البشرية ... جميع المحاضرات بصيغة بوربوينت
شير لعلها تكون المنجية لنا جميعا
This post is for charity ...
Links to PowerPoint presentations in poultry diseases, medications, and immunity in addition to soft skills courses
Share to benefit others
ادوية علاج الدواجن من المضادات الحيوية ومستخلصات الأعشاب
Poultry medications (antibiotics and herbal extracts)
Link to download more presentations in powerpoint
https://lnkd.in/gJGGnPY
امراض الدواجن البكتيرية والفيروسية واساسات التحصينات ومناعة الطيور
Poultry diseases, vaccination and immunity
Link to download presentations in powerpoint
https://lnkd.in/g2ef7DP
كورسات التنمية البشرية
Soft skills courses
Link to download presentations in powerpoint
https://lnkd.in/g8W7TYq
Presentations are continuously updated
المكتبة متجددة باستمرار
البوست ده عمل خيري ...
دي لينكات لمحاضرات في امراض وادوية الدواجن وكورسات التنمية البشرية ... جميع المحاضرات بصيغة بوربوينت
شير لعلها تكون المنجية لنا جميعا
This post is for charity ...
Links to PowerPoint presentations in poultry diseases, medications, and immunity in addition to soft skills courses
Share to benefit others
ادوية علاج الدواجن من المضادات الحيوية ومستخلصات الأعشاب
Poultry medications (antibiotics and herbal extracts)
Link to download more presentations in powerpoint
https://lnkd.in/gJGGnPY
امراض الدواجن البكتيرية والفيروسية واساسات التحصينات ومناعة الطيور
Poultry diseases, vaccination and immunity
Link to download presentations in powerpoint
https://lnkd.in/g2ef7DP
كورسات التنمية البشرية
Soft skills courses
Link to download presentations in powerpoint
https://lnkd.in/g8W7TYq
Presentations are continiously updated
المكتبة متجددة باستمرار
Seven Cs of Effective Communication_Life Time Example.pptxOssama Motawae
"عسى ان يكون علما ينتفع به"
Communication
دي لينكات لمحاضرات في امراض وادوية الدواجن وكورسات التنمية البشرية ... جميع المحاضرات بصيغة بوربوينت
ادوية علاج الدواجن من المضادات الحيوية ومستخلصات الأعشاب
Poultry medications (antibiotics and herbal extracts)
Link to download more presentations in PowerPoint
https://drive.google.com/open?id=1EtFtygmlvOYqjqpanRTIgoExIENd-YIB
امراض الدواجن البكتيرية والفيروسية واساسات التحصينات ومناعة الطيور
Poultry diseases, vaccination, and immunity
Link to download presentations in PowerPoint
https://drive.google.com/open?id=1znC0qeHMivV2ai4_IUweA-VTBQLJSVKu
كورسات التنمية البشرية
Soft skills courses
Link to download presentations in PowerPoint
https://drive.google.com/open?id=1R3CqcFO10bOyi1aRQx0WNSn6B5TMNMxu
Seven Cs of Effective Communication_Tips.pptxOssama Motawae
"عسى ان يكون علما ينتفع به"
Communication
"عسى ان يكون علما ينتفع به"
Communication
دي لينكات لمحاضرات في امراض وادوية الدواجن وكورسات التنمية البشرية ... جميع المحاضرات بصيغة بوربوينت
ادوية علاج الدواجن من المضادات الحيوية ومستخلصات الأعشاب
Poultry medications (antibiotics and herbal extracts)
Link to download more presentations in PowerPoint
https://drive.google.com/open?id=1EtFtygmlvOYqjqpanRTIgoExIENd-YIB
امراض الدواجن البكتيرية والفيروسية واساسات التحصينات ومناعة الطيور
Poultry diseases, vaccination, and immunity
Link to download presentations in PowerPoint
https://drive.google.com/open?id=1znC0qeHMivV2ai4_IUweA-VTBQLJSVKu
كورسات التنمية البشرية
Soft skills courses
Link to download presentations in PowerPoint
https://drive.google.com/open?id=1R3CqcFO10bOyi1aRQx0WNSn6B5TMNMxu
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
2. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
3. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
5. Cont. …
The chicken anemia virus (CAV) was
first described in 1979 by Yuasa et al.
(1979) in commercially produced
chickens.
Since that time, the virus has been
detected by isolation or serology in
most other countries in both laying
and broiler chickens (von Bulow and
Schat, 1997).
6. Cont. …
It is generally accepted that chickens are the natural hosts of
CAV.
All ages of chickens can be infected, the most severe clinical
signs are seen in chickens younger than 2 weeks of age.
CAV has also been isolated from other species such as turkeys
and CAV antibodies have been detected in quails.
7. Cont. …
The importance of this virus comes from its:
1. Trans-ovarian transmission.
2. Potential for inducing immunosuppression alone or in
combination with other infectious agents.
8. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
10. Cont. …
The economic impact of CAV is mainly due to:
1. Bad performance (poor FCR and reduced weight gain).
It has been proven that flocks that appear normal, but
suffered from a subclinical CAV infection, performed less well
when compared to flocks that remained negative throughout
the growing period.
2. Increased condemnation rates at slaughter.
3. Presence of secondary infections.
4. Vertical transmission from breeders to their progeny which
may result in clinical disease.
11. Cont. …
The effect of a subclinical CAV infection on the performance
parameters of broilers was well documented by McNulty et al.
CAV status
% net
income
Bonus % FCR Weight % Mortality %
- +2.4 +2.7 -0.4 +0.8 -0.16
+ -10.6 -8.8 +1.6 -1.7 +0.24
12. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
14. Cont. …
Able to withstand pH of 3 and chloroform.
Not inactivated by heating at 70°C for one hour or after 5
minutes at 80oC.
Resistant to lipid solvents and to treatment for 2 hours at 37°C
with 5% solutions of commercial disinfectants (quaternary
ammonium compounds, amphoteric soap and
orthodichlorobenzene)
15. Etiology
Virus Serotypes
All Chicken Anemia Virus isolates belong to one serotype,
although antigenic differences among isolates have been
reported in the United States.
16. Pathogenesis
CAV can be found latent in SPF flocks where the virus was
detected in the ovaries, oviduct, testicles and spleen of birds
without obvious seroconversion until the birds came into
production.
17. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
18. Transmission
Disease usually occurs during the first 3 week of life through;
1. Vertical transmission when breeder flocks get infected
during the production period; this occurs especially in
younger flocks.
2. Horizontal transmission through infected organic
material or contaminated equipment.
Chickens at any age are susceptible to infection by:
1. Oral route.
2. Respiratory route.
19. Cont. …
In younger birds the presence of clinical signs depends on:
1. The challenge dose.
2. The level of the maternally derived antibodies.
3. The presence of other immunosuppressive agents (such as
marek’s disease virus, reovirus or infectious bursal disease
virus).
Immunosuppressive agents act synergistically increasing the severity of
the disease and overriding the protective effect age and maternal
antibodies.
20. Cont. …
Incubation period
CAV is not highly contagious and it takes few weeks to spread
through an entire flock.
The incubation period is relatively long under field conditions,
with the disease taking weeks to spread through the entire
flock.
21. Cont. …
Organ affinity
The virus can be isolated from different organs but targets
mainly the thymus, therefore impairing the maturation of T
lymphocytes.
Under experimental conditions, the virus is found present in
most organs after one day (brain, liver, spleen, bursa, bone
marrow, rectal contents and serum).
22. Cont. …
Morbidity and mortality rates are high dependent on the age
of the chickens when infected.
23. Cont. …
Age resistance
Chickens develop “age resistance” to disease > 2-3 weeks of
age, but remain susceptible to infection.
The period of susceptibility to disease may be extended by
early exposure to IBDV, Marek’s disease virus, or selected
avian reo viruses that interfere with normal immune system
development (Engstrom et al., 1988; von Bulow and Schat,
1997).
24. Cont. …
Post infection complications
8 days post infection haematocrit levels, thrombocytes and
red and white cell counts decrease.
Increased blood clotting time, blood takes longer to clot.
Between 28 – 36 days post infection the heamathological
parameters in recovered birds return to normal.
25. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
26. Clinical Signs
Birds of all ages are susceptible to infection but the clinical
signs are mainly seen in young birds <2 weeks of age.
Most outbreaks occur in broilers, followed by replacement
pullets and are acutely reported at around 2 - 3 weeks of age.
Outbreaks in older birds (replacement pullets) have been
reported when other immunosuppressive agents are involved
(like Marek's Disease virus and/or Infectious Bursal Disease
virus).
27. Cont. …
The following may be seen:
1. Young chickens are depressed and huddle under the heat
source.
2. The birds appear less developed for their age and anaemic.
28. Clinical Signs
1. Anorexic.
2. Depressed.
3. Exhibit a marked pallor that may extend to the internal
organs.
4. Hemorrhages can be observed in the musculature and
subcutaneously, with the wing tips frequently affected.
5. The bone marrow is pale or yellow in color and may have a
fatty consistency.
29. Cont. …
6. Thymic atrophy and congestion is common and is considered
diagnostic when associated with other typical signs or
lesions.
7. Bursal atrophy is generally modest and transitory, typically
occurring at 10 to 14 d of age in chickens vertically infected.
30. Cont. …
Complications
All of the aforementioned lesions are exacerbated and more
persistent in chickens coinfected with infectious bursal
disease virus or other lymphocidal agents.
Severely affected birds generally die within 2 to 4 week of age
Survivors are often stunted.
31. CAV and Immunosuppression
The most important consequence of a CAV infection is
immunosuppression.
CAV infection impairs the immune system, affecting and
multiplying in most lymphopoietic organs.
CAV will have an impact on the generation of cytotoxic T
lymphocytes to other pathogens (lymphocyte depletion).
CAV enhances the effect of other immunosuppressive agents
such as Marek’s Disease virus and Infectious Bursal Disease
virus.
32. Cont. …
There are also reports of enhanced signs after Infectious
Bronchitis infection due to immunosuppression.
The reduction in the development of antibodies after
vaccination against Newcastle Disease in CAV infected birds
has been well documented.
33. Cont. …
Because of the immunosuppression, affected chickens
frequently develop secondary infections with Clostridium
perfringens and Staphylococcus aureus in the subcutaneous
tissues and musculature that results in losses due to
gangrenous dermatitis.
There may also be an increased susceptibility to adenovirus-
associated inclusion body hepatitis and respiratory disease.
34. Gangrenous dermatitis in the wings - Blue Wing disease (BWD)
The skin lesions begin generally from wings and the adjacent areas.
Gangrenous dermatitis in the wings
Blue Wing disease (BWD)
35. Haemorrhages on the wing of a young chicken with Chicken Infectious Anemia, hence
the name Blue Wing Disease.
36. Subcutaneous haemorrhages on the wing of a young chicken with Chicken Infectious
Anemia. The name "Blue Wing Disease" is as a result of the blue discoloration seen.
37. Subcutaneous haemorrhage in a young chicken with Chicken Infectious Anemia,
resulting in blue discoloration of the hock joint.
38. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
39. Poste Mortem Lesions
Focal lesions (mostly in the wings) appear as ecchymotic skin
haemorrhages.
The lesions turn blue and may break, releasing
serosanguineous exudate which is prone to secondary
bacterial infections, leading to gangrenous dermatitis.
This can be especially notorious at the end of the wings,
hence the name “Blue Wing Disease” used to describe this
condition.
The tips of the wings may appear haemorrhagic and necrotic.
40. Cont. …
The mortality peaks 5 -6 days after the appearance of the
clinical signs, declining to normal 5 – 6 days later.
Thymus atrophy with lobes appearing small and greyish.
When observed closely, the medullar part of the lobes
predominate over the cortical part.
Bone marrow atrophy, when observed closely it appears pale.
46. Poste Mortem Lesions
Histology
Bone marrow
Decrease in the number haematopoietic cells is observed 4 –
6 days post infection.
Followed by the appearance of large blastic cells.
The haematopoietic tissue is replaced by adipose tissue; this
gives the bone marrow a pale appearance.
47. Cont. …
Other organs
Depletion of lymphocytes from the thymus, spleen, Bursa
Fabricius and caecal tonsils is observed, followed by
hyperplasia of reticular cells.
Changes in the thymus appear at 4 days post infection, with
cortical lymphocytes disappearing and being replaced by
reticular cells.
Medullar lymphocytes are also reduced.
Recovery starts 20 days post infection in convalescent birds.
The changes found in the different organs suggest that CAV
multiplies in the lymphocytes.
48. Cont. …
The bursa of Fabricius and spleen may also be depleted of
lymphoid cells, but the involvement and duration is less
extensive than seen with the thymus.
Survivors of CAV infection usually return to normal by
approximately 4 week of age, which coincides with the onset
of measurable antibody responses.
49. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
50. Diagnosis
Clinical signs in young chicks are indicative of CAV infection but
laboratory tests are required for a definitive diagnosis.
51. Cont. …
Clinical signs
Diagnosis on the basis of clinical signs is very difficult.
Very often the clinical disease may present itself in milder
forms making it impossible to make a proper diagnosis.
Post mortem findings are often not conclusive.
52. Cont. …
Laboratory tests
Laboratory tests to identify the viral genome, antigen or
antibodies are required for a definitive diagnosis.
Testing serum samples for example at the time of the clinical
signs and 2-3 weeks later provide the best basis for serological
diagnosis.
This is also applicable for monitoring vaccination results.
The retrospective testing of sera from breeders could be done
in cases where vertical transmission is suspected.
53. Plan of Talk
Introduction
Economic importance
Etiology
Transmission
Clinical signs
Post mortem lesions
Diagnosis
Prevention and control
54. Prevention and Control
Because the widespread distribution of the virus, being very
resistant to inactivation and easily transmitted, it is probably
unrealistic to assume that exposure can be limited with
conventional housing and production parameters.
Prevention and control of this disease requires a well
coordinated approach, balancing biosecurity / hygienic
measures and vaccination.
55. Cont. …
Control measures are directed at:
1. Limiting vertical transmission
2. Preventing coinfections with other lymphocidal agents.
56. Prevention and Control
Biosecurity
1. Basic management practices such as limited controlled site
access, separate footwear and equipment for each
site/house, and footbaths at the entrance to sites/houses all
minimize the risk of introducing the virus.
2. Dry clean:
Removal and disposal of all organic material from the site.
3. Wet clean:
Clearing poultry houses using water at high pressure (35-55 Bar) to
ensure removal of all organic material.
It is advisable to add detergents to assist the cleaning process.
57. Cont. …
3. Disinfection:
Application of a suitable disinfectant to reduce infectivity of
any remaining virus particles.
Applying disinfectants at the correct concentration with a
suitable contact time is critical.
Generally products containing formaldehyde, chlorine
releasing agents, or quaternary ammonium compounds are
suitable within the context of minimizing virus (and lowering
infective dose) in the environment, rather than assuring
complete inactivation.
58. Cont. …
4. The downtime between successive flocks must be maximized
(a minimum of 10 days is recommended).
The control of CAV on multi-age sites is extremely challenging and
requires strict control of the movement of personnel and equipment
between houses.
59. Prevention and Control
Vaccination Program
The aim of vaccination is to protect the progeny from early
infections (before 3 weeks) by means of maternally derived
antibodies.
60. Cont. …
The immunization of breeding stock, several weeks before
onset of lay, will efficiently prevent outbreaks of infectious
anemia caused by CAV in their progeny.
Furthermore, if high uniform antibody levels can be induced
in breeding stock, the resulting high levels of maternally
derived antibodies (MDA) prevent or at least delay horizontal
infection in the progeny and thus prevent or decrease
economic losses due to subclinical disease.
61. Cont. …
Breeders
Breeders are vaccinated during the rearing period between 8-
16 weeks of age with a live vaccine.
Care should be taken to ensure that vaccination results in high
levels of maternally derived antibodies throughout the
production period.
62. Cont. …
Broilers and layer pullets
Broilers and layer pullets are not commonly vaccinated
against CAV in the field.
Early protection is achieved by vaccination of the breeders
though MDA.
63. Maternal Immunity
Maternally derived antibodies (MDA) offer protection against
CAV infections, CAV and related infections do not appear in
the progeny of immune breeder flocks.
The level of protection is directly related to the level of MDA,
the higher the MDA level, the longer the protection in the
progeny
64. Cont. …
MDA develop after field infections and/or vaccination
Field infections do not guarantee high and homogenous
levels of MDA
Vaccination is the best way of promptly obtaining high and
homogenous levels of MDA
65. Cont. …
Minimum protection level
Breeders with different levels of MDA were challenged by
inoculation with CAV
Vertical transmission was evaluated by re-isolation of CAV
from the faeces as this correlates with transmission through
the eggs.
Birds with VN titers <7 (log2) still shed the challenge virus
Birds with a VN titer of 7 (log2) sporadically shed the virus
Birds with VN titers >7 (log2) did not shed the virus
66. Cont. …
Conclusion
To avoid vertical transmission, a MDA titer of > 8 log2 is
needed.
The higher the MDA level, the longer the protection in the
progeny.
Editor's Notes
haematocrit is the volume percentage (%) of red blood cells in blood
Pallor is a pale color of the skin which can be caused by illness, emotional shock or stress, stimulant use, or anemia, and is the result of a reduced amount of oxyhaemoglobin in skin or mucous membrane.