By Prof. Dr. Mohamed H. H. Awaad Faculty of Veterinary Medicine, Cairo University Infectious...
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Transcript of By Prof. Dr. Mohamed H. H. Awaad Faculty of Veterinary Medicine, Cairo University Infectious...
ByProf. Dr. Mohamed H. H. Awaad
Faculty of Veterinary Medicine, Cairo University
Infectious stuntingInfectious stuntingsyndromesyndrome
(ISS)(ISS)
Malabsorption syndrome Helicopter disease Umbrella-bird Brittle bone disease Stunting-runting syndrome Chicken anemia Pale bird syndrome.
In turkeys:Turkey viral enteritis, Poult enteritis, Malabsorption syndrome Maldigesion syndrome.
SynonymsSynonyms
DefinitionDefinitionInfectious disease
that affects the intestinal tract of
young broilers and specially breeders. Characterized by
severe growth depression.
EtiologyEtiology
Primary cause(s) has not definitely establishedPrimary cause(s) has not definitely established
Enteropathogens causing viral enteric infectionsEnteropathogens causing viral enteric infections
ReovirusesOther viruses
Orthoreoviruses (in turkeys)Orthoreoviruses (in turkeys)
Togaviruslike agentTogaviruslike agent
FEW virusFEW virus
Coronaviruslike particlesCoronaviruslike particles
CalicivirusesCaliciviruses
AdenovirusesAdenoviruses
ParvovirusesParvoviruses
Reticuloendotheliosis virus, several other bacteria and non-infectious
agents (e.g. Mycotoxins) have been claimed to be involved.
Economic lossesEconomic losses
Carcass condemnationCarcass condemnationMarketabilityMarketability
Feed conversionFeed conversionDiminished weight gainsDiminished weight gains
Pathogenesis and epizootiology
The enteric tract has many functions:The enteric tract has many functions:
3- Serves as an environment for other living organisms.2- Furnishes protective mechanisms to safeguard the host.
1- Providing a means by which the body derives nutrition.
So Combination of, and interactions among viruses, bacteria, parasites and
non-infectious agents may be necessary to elicit or increase severity
of viral enteric disease.
Pathogenesis and Pathogenesis and epizootiologyepizootiology
Enterolike viruses infectEnterolike viruses infect villous epithelial cellsvillous epithelial cells
Obstruction.Obstruction.Togaviruslike agent isolatedTogaviruslike agent isolated from pancreatic ductsfrom pancreatic ducts
MaldigesionMaldigesionPancreatic lesionsPancreatic lesions
Dysfunction Dysfunction of intestineof intestine..
Vertical and horizontal transmission Vertical and horizontal transmission of these viruses are proven.of these viruses are proven.
Viruses Infect villous epithelial cells in the mid-
small intestine
Decreased Wt. gains
Dysfunction of the intestine leads to impaired digestion and absorption of lipids and fat-soluble vitamins A, D and E
and carotenoids.
Stunts (Uneven growth)
Runts(Very small birds about 120-150 g)
Symptoms
Yellow-head
Witch-like appearance of
the beak
Poor pigmentation (Pale-bird syndrome)
Granulation in eye-lids
Feathers
Skeletal abnormalities (lameness -
brittle bones)
Encrustation of mouth commissars Encephalomalacia
0range diarrhea
Feed conversion - Mortality
Enlarged abdomen
Stunts-RuntsStunts-Runts
Post mortem Lesions
Enlarged proventriculusEnlarged proventriculus
Distended abdomenDistended abdomen
Shrunken, thin, white and firm Shrunken, thin, white and firm pancreaspancreas
Intestine containing undigested orange
feed
Catarrhal enteritis with white color and Dilated
intestine.
Bursa of Fabricius and thymus gland are atrophied.
Femoral head disintegration on disarticulation of the coxofemoral joint
Thickening of the growth plates of long bones.
Arthritis and osteoporosis.
Other gross lesions
Histopathological lesions
Early stages:Degeneration, atrophy, and fibrosis of exocrine
tissue of pancreas. Marked vacuolation of acinar cells.
Later stages:Extensive atrophy of exocrine tissue and fibrous replacement of pancreatic acini
PancreasPancreas
Catarrhal enteritis, atrophic intestinal villi, inflammation and degeneration of crypts of Liberkuhen glands with
lymphocyte infiltration.
IntestineIntestine
Thymus cortex is thinner and difficult to be differentiated from medulla.
Atrophy of follicles of Bursa of Fabricius.
Bones abnormality in the femur growth plate with necrosis of cartilage.
Proventriculitis with focal necrosis and infiltration of interglandular tissue with mononuclear cells.
Other histopathological Other histopathological lesionslesions
Diagnosis
Signs and lesions are quite sufficient for routine diagnosis.
Prevention and Control
1- Thorough cleaning and disinfecting of the affected premises after each
crop ( Basic Veterinary hygienic measures).
2-In affected flocks dietetic measures, such as the use of good quality fat and / or replacement of fat energy by carbohydrates are of some help.
Prevention and Control..Cont.
4- Vaccines (at 1 day of age with viable attenuated Reovirus by S/C) route or vaccination of breeders (with viable or
inactivated vaccines) provides maternal immunity as well as limits transovarian
transmission.
3-Research into a broiler that resist ISS breeds is on its way.
Thank you