Gumboro Disease in Poultry: Symptoms, Treatment & Prevention

Gumboro Disease, also known as Infectious Bursitis or Bursal Disease, is a highly contagious viral infection that primarily affects young chickens up to 9 weeks of age. It is characterized by high mortality rates, anorexia, diarrhea, and depression.

The disease targets the Bursa of Fabricius, leading to the destruction of lymphocytes and immune suppression in infected chickens. This immune suppression increases their vulnerability to other health challenges, resulting in poor performance and economic losses.

Gumboro Disease is caused by the Infectious Bursal Disease Virus (IBDV), which belongs to the Birna Virus genus. There are two serotypes of the virus, with vaccination against serotype two not protecting against serotype one.

Transmission of Gumboro Disease:

Gumboro Disease spreads through the fecal-oral route in poultry. Birds infected with the IBDV shed the virus in their feces, and other birds become infected by ingesting the virus.

The infection is highly contagious, and affected chicks excrete the virus for up to two weeks after infection. Direct contact, inhalation, or consumption of contaminated feed and water can also transmit the virus.

It's worth noting that there is no evidence of egg transmission or carriers, but the darkling beetle can spread the disease.

Pathogenesis of Gumboro Disease:

Gumboro Disease is caused by IBDV, which leads to bursal lesions, atrophy, and immunosuppression. The virus primarily targets B lymphocytes and is transmitted through the fecal-oral route.

It affects lymphoid tissue, leading to the destruction of lymphocytes in the Bursa of Fabricius, spleen, and caecal tonsils. Following infection, there is a short incubation period of two days, and the bursa becomes congested and enlarged. Surviving birds experience rapid tissue regeneration.

Clinical Signs of Gumboro Disease:

Within 48-72 hours after infection, birds show clinical signs of Gumboro Disease. The most severe impact is observed in birds aged 4-5 weeks, and the disease can affect birds up to 9 weeks old.

Clinical signs include abrupt cessation of feeding, sudden onset of white watery diarrhea, severe depression, ruffled feathers, vent pecking, trembling, dehydration, and weight loss.

The flock appears unkempt, and mortality rates can range from 30-50% in subsequent infections. However, mortality decreases over time.

In the subclinical form, there are no visible signs, but immune suppression makes birds susceptible to other diseases such as E. coli infection, Coccidiosis, and enteritis, leading to poor responses to vaccination.

Postmortem Lesions of Gumboro Disease:

Postmortem examination reveals dehydrated carcasses, hemorrhages in leg and thigh muscles, and occasional mucosal hemorrhages in the proventriculus.

Bursitis, characterized by swelling and hemorrhage or edema, may be present, surrounded by gelatinous fluid. The bursa decreases in weight by one to three times its original weight by day 8.

The kidney, liver, and spleen may also show signs of swelling.

Treatment and Control of Gumboro Disease:

There is no specific treatment for Gumboro Disease. Supportive treatments, such as vitamins and electrolyte supplements, and antibiotics, are used to address secondary infections and reduce the impact of the disease.

Prevention and control of the disease involve implementing strict biosecurity measures. Vaccination is the most effective method, coupled with good sanitation practices. However, the virus is highly stable and resistant in the environment, making it challenging to eradicate.

Depopulation, thorough cleaning, and disinfection of infected farms have had limited success in preventing the spread of the disease.

It's crucial to follow a strict vaccination program after restocking, and breeding birds should be vaccinated to protect chicks for up to 3 weeks.

Chicks themselves should be vaccinated at specific intervals, such as on days 7 and 28. Maintaining good sanitation practices and adhering to rigorous biosecurity measures are essential for disease control.

Conclusion

In conclusion, understanding the characteristics, transmission, clinical signs, and postmortem lesions of Gumboro Disease is essential for poultry farmers. Strict biosecurity measures, vaccination programs, and good sanitation practices are vital for preventing and controlling these highly contagious viral diseases and minimizing their impact on poultry farms.

Gumboro Disease, caused by the infectious bursal disease virus (IBDV), primarily affects young chickens up to 9 weeks old. It is characterized by high mortality, anorexia, diarrhea, and depression. The virus targets lymphoid tissue, particularly the Bursa of Fabricius, leading to the destruction of lymphocytes and subsequent immune suppression. This immune suppression makes chickens more susceptible to other diseases and negatively impacts their performance and economic returns.

Gumboro Disease transmission occurs through the fecal-oral route, with infected birds shedding the virus in their feces. Other birds become infected by ingesting the virus, and transmission can also occur through direct contact, inhalation, or contaminated feed and water. It is important to note that the darkling beetle can spread the disease, but there is no evidence of egg transmission or carriers.

Pathogenesis of Gumboro Disease involves the IBD virus causing bursal lesions, atrophy, and immunosuppression. The virus mainly targets B lymphocytes and is transmitted primarily through the fecal-oral route. It affects lymphoid tissue, including the Bursa of Fabricius, spleen, and caecal tonsils. After infection, there is a short incubation period, and the bursa becomes congested and enlarged. If the bird survives, rapid tissue regeneration occurs.

Clinical signs of Gumboro Disease manifest within 48-72 hours post-infection, with birds at 4-5 weeks of age being most severely affected. Symptoms include sudden cessation of feeding, white watery diarrhea, severe depression, anorexia, ruffled feathers, vent pecking, trembling, dehydration, weight loss, and an unkempt appearance.

Mortality rates can range from 30-50%, with death occurring within 2 days of the first signs of the disease. In the subclinical form, birds may show no clinical signs, but their immune suppression makes them vulnerable to other diseases and reduces their response to vaccination.

Postmortem lesions in Gumboro Disease include dehydration of the carcass, hemorrhages in leg and thigh muscles, and occasionally mucosal hemorrhages in the proventriculus. Bursitis is characterized by swelling, hemorrhage, or edema and is often surrounded by gelatinous fluid. The bursa decreases in weight by one to three times its original weight by day 8. The kidney, liver, and spleen may also show signs of swelling.

There is no specific cure for Gumboro Disease. Supportive treatments, such as vitamins and electrolyte supplements, as well as antibiotics to address secondary infections, are commonly used to alleviate the impact of the disease.

Preventing and controlling Gumboro Disease requires strict adherence to good sanitation practices. Vaccination plays a good role in disease control, especially in breeding birds to protect chicks. Chicks themselves should be vaccinated at specific intervals. After an outbreak, thorough cleaning, disinfection, and a resting period of at least four months are necessary before restocking. Following a well-designed vaccination program after restocking is essential.