viral respiratory disease
TRANSCRIPT
Respiratory Viral Infection in poultry
MEMBER IN INTERNATIONAL NETWORK FOR POULTRY DEVELOPMENTFAO
FAO IRAQ
Dr. Majed H. Mohammed Ph.D.Virology and Moleculat Cell Biology
Conclusions
current study revealed that the presence ofbacterial co-infection (E.coli and MG) with the IB viruscomplicated the disease process and increased the mortality ratein the farms that was approximately 60-75% which caused higheconomic losses.
The comparative analysis of the recent genotypes circulating inSlemani with the IB vaccine strains (Massachuset and 4/91)revealed that these vaccines not able to protect farms from IBVinfection, otherwise using of these live virus vaccine may causemutation and spreading of the virus in the flock.
This study indicates the existence of three IBV genotypes (A; Band C) circulating in Slemani, (genotypes group A and group B),
were respiratory types IBV, which were detected from respiratorytissues of the infected chickens, while (genotype group C) was anephropathogenic type IBV which was detected from kidneys ofthe infected chickens.
According to the comparative analysis in the current study the low nucleotide and amino acid similarities were found between the circulating isolates in Slemani and (H120, MA5) Massachusetts and 4/91 vaccine strains. It has been found that genotype group A is (33- 35%) different from all vaccine strains, genotype group B is (32- 35%) different from all vaccine strains while genotype group C is (20%) different from all vaccine strains. The poor relationship in the partial S1 sequence between the three IBV isolates and the vaccinestrains
Center for Food Security and Public Health, Iowa State University, 2008
Influenza Virus
• Family Orthomyxoviridae– “myxo” means mucus
• Three main types– Type A
• Multiple species
– Type B• Humans
– Type C • Humans and swine
Center for Food Security and Public Health, Iowa State University, 2008
Avian Influenza
• Disease based on genetic features and/or severity of disease in poultry– Low pathogenic AI (LPAI)
• H1 to H16 subtypes
– Highly pathogenic AI (HPAI)• Some H5 or H7 subtypes• LPAI H5 or H7 subtypes can mutate
into HPAI
Center for Food Security and Public Health, Iowa State University, 2008
Avian Influenza
• Incubation period: 3-14 days • Birds found dead• Drop in egg production• Neurological signs• Depression, anorexia,
ruffled feathers• Combs swollen, cyanotic• Conjunctivitis and respiratory signs
Center for Food Security and Public Health, Iowa State University, 2008
Post Mortem Lesions
• Lesions may be absent with sudden death• Severe congestion of the musculature• Dehydration• Subcutaneous edema of head
and neck area
Post Mortem Lesions
• Nasal and oralcavity discharge
• Petechiae onserosal surfaces
• Kidneys severely congested• Severe congestion of the
conjunctivae
Treatment
There is no effective treatment for avian influenza. However, good husbandry, proper nutrition, and broad spectrum antibiotics may reduce losses from secondary infections. It must be remembered that recovered flocks continue to intermittently shed the virus.All buildings should be cleaned and disinfected after an infected flock is removed. The poultry litter or manure should be dung before application to cultivated lands.
Newcastle disease virus
NDV also called (avian paramyxovirus type I,
pneumoencephalitis virus & pseudo-fowl pest).ND is contagious and fatal viral disease affecting
most species of birds (chickens, turkeys, pigeons ,parrots ,ducks, geese, quails)and human.
Taxonomy of the NDV : Family: Paramyxoviridae. Subfamily: Paramyxovirinae. Genus: Avulavirus.
Transmission : Direct contact between healthy birds and the
infected bird discharges. Contaminated feed, water, equipment and
clothing. Virus can be picked up on shoes and clothing and
carried from an infected flock to a healthy one. Airborne spread. Contaminated poultry vaccines. Other animals and birds transporting the virus
from farm to farm.
Incubation period :
It varies from (2 to 15) days in poultry depending on the virulence of the strain.
In chickens infected with velogenic isolates; (2 to 6) days.
In some avian species; 25 days. Pathogenesis : The virus replicates in the mucosa of the upper
respiratory and intestinal tracts. Virus spreads via blood to spleen and bone marrow
(viremia) causing infection of other organs: lung ,intestines & C.N.S.
Clinical Signs and Symptoms : Respiratory symptoms. Nervous signs. Digestive symptoms. Drop in egg production with thin, rough-shelled
eggs. Swelling of tissues around eyes and in the neck. Sudden death. In human;(Mild conjunctivitis, influenza-like
symptoms and laryngitis).
Fig2; Coughing and gasping.
Fig3; Mouth discharges.
Fig4; The bird displays torticollis.
Fig8; Diarrhea with green bile pigment and white urates.
Fig9; Square appearance of the head due to bilateral facial edema.
PM and gross les ions :
Inflammation with Petechial hemorrhages on proventriculus mucosa.
Edematous, hemorrhagic, necrotic, and ulcerative areas on Peyer's patches, caecal tonsils.
Edematous, hemorrhagic, or degenerated ovaries.
Fig13; subconjunctival haemorrhages with external lesions.
Fig14; Odema and hemorrhages in the conjunctiva and infraorbital sinus.
Fig15; Accumulation of mucus in the respiratory tract.
Fig16; Mild haemorrhagic lesions in the mucosa of trachea.
Fig17; Congestion and haemorrhages in the pharynx and
proximal trachea.
Fig18; Sever thymus atrophy with extensive haemorrhages.
Fig19; Inflammation with pinpoint heamorrhagic lesions in the proventriculus mucosa.
Fig20; Necrosis of lymphoid tissue at the caecal tonsils.
Fig21; Extensive haemorrahges and ulcers of caecal tonsils mucosa.
Vaccination
GOODVACCINATION
PROGRAMDESIGN
Basics of Vaccination in PoultryElements of a Vaccination Program
Interval betweenSubsequentVaccinations
Route ofVaccination
Age of theFirst Vaccination
Type ofVaccines
Number ofVaccinations
1. Stimulation & Maintenance of Protective Immunity2. Development of Immunologic Memmory
GOODIMMUNE
RESPONSE
Basics of Vaccination in PoultryRequirements for Good Immune Response
No Immune
Suppression
Healthy Birds
Good Administration
Technique
Correct Vaccination Programme
Good Nutrition Correct Vaccine Storage
Correct Vaccine
No Stress
Newcastle Vaccination
Immunity Against ND
