Avian infectious bronchitis (ib), Biology

Avian infectious bronchitis (IB)

An acute, highly contagious respiratory disease of chicken caused by a member of the family Coronaviridae, IB was first recognized in India in 1969. The virus can be propagated in 10-day-old embryonated chicken eggs resulting in dwarfing and curling of embryos. Transmission occurs through direct contacts, aerosol and contaminated fomites. Transovarian transmission does not occur. Birds of all ages are susceptible but chicks below 4 weeks of age are severely affected.

Symptoms and lesions: Clinically the birds show depression and respiratory distress like coughing, gasping, sneezing and discharges from the eyes and nostrils. Sometimes the respiratory signs may be too mild to be noticed. The virus at times attacks the oviduct and the kidney, resulting in significant reduction in egg production and poor quality eggs. Early infection of the chicks may result in damage to oviduct and such birds fail to lay eggs. Infection of layers leads to lowered egg production and eggs laid may be misshapen, rough, soft shelled and with poor hatchability. In young chicks mortality may go upto 25%. In the renal form of the disease mortality may occur in broilers. Recovered birds may act as carriers for several days. The PM lesions seen are congestion of lungs and cloudy air sacs, catarrhal exudates or caseous plugs in the trachea and on lungs. When there is involvement of oviduct, regression of size and absence of duct are seen. When nephropathic strains are involved the kidney may be swollen and pale with tubules and ureters distended with urates.

Diagnosis: Clinical symptoms and lesions are indicative of infection. Final confirmation is done on the basis of isolation and identification of the virus. Virus can be isolated in 10-11 day old chicken embryos inoculated with trachea, caecal tonsils and oviduct and kidney tissue homogenate from suspected birds.

Prevention and control: Proper hygiene and good management is necessary. Live vaccines are used in broilers and for initial vaccination of breeders and layers. Inactivated oil adjuvanted vaccines are primarily used at the point of lay in breeders and layers. Best protection with inactivated vaccine can be obtained only if it is given after priming the birds with live vaccines.

Posted Date: 9/18/2012 8:43:09 AM | Location : United States







Related Discussions:- Avian infectious bronchitis (ib), Assignment Help, Ask Question on Avian infectious bronchitis (ib), Get Answer, Expert's Help, Avian infectious bronchitis (ib) Discussions

Write discussion on Avian infectious bronchitis (ib)
Your posts are moderated
Related Questions
Q. Illustrate about Sterilization protocol? Sterilization protocol includes proper transportation and cleaning of instruments followed by their packing. Items can be sterilized

Q. What is packaging? What is packaging? Packaging means a coordinated system of preparation of goods (in this case, foods) for shipment, distribution, storage and

What is the virus that causes flu? Why doesn't the body create permanent immunity against that virus? How does the vaccine against flu work? Flu is a disease caused by the inf

Cell theory is a theory that asserts that the cell is the ingredient unit of the living beings. Before the discovery of the cell, it was not examined that the living beings were

Techniques :  Depending on the type of surgery planned, the heart may be approached through median sternotomy, left or right thoracotomy. The problems encountered could be due to

Q. Amphibian identity card. How are amphibians characterized according to examples of representing beings, basic morphology, circulation, skin, nitrogen waste, respiration, thermal

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) - These drugs are direct, non-nucleoside inhibitors of HIV-1 reverse transcriptase. Combinations of an NNRTI with NRTIs

What happens to a denatured enzyme regarding its functionality? How can that result be explained with the help of the lock and key model? According to the lock and key model th

Q. How many ATP molecules are made after glycolysis? Glycolysis is a process similar to glucose degradation in fermentation it produces final balances two molecules of ATP for

Adverse effects of menactra The most common adverse reactions to Menactra include headache, fatigue and malaise, in addition to pain, redness and induration at the site of injec