Veterinary discussion: Gumboro or infectious bursa disease, IBD is a viral disease in chickens, common and easily found in the field. IBD virus can attack many organs, but the main target of this virus is the bursa of Fabricius. So that pathological lesions on the bursa of Fabricius become the main symptoms for many people to diagnose this disease in the field.
This virus can also make pathological lesions on the muscles, spleen and proventriculus. But the lesion on the bursa of Fabricius is often used as the main indicator for many people to diagnose this disease. Since the bursa of Fabricius is the main target of this virus, we often assume that this virus will result in the most severe lesions in this organ than any other organ.
So finding the pathological lesion on the stock of Fabricius becomes the absolute thing to make a diagnosis of gumboro, IBD in the field. Yes, that may be true. But the field is not always like that. In many cases of gumboro, infectious brusa disease especially in the breed chicken layer, muscle lesions are often found to be more severe than in the bursa in acute cases.
The lesions of gross pathology in the bursa become symptomatic pathognomonic for IBD, but in the field, observation of anatomical gross pathology will be biased. Many diseases cause similar lesions in the bursa of Fabricius. Velogenic Newcastle disease, and bird flu, high Pathogenic Avian Influenza H5N1.
Observe the image below, compare the lesions in chickens 1,2 and 3!
layer breeds are most susceptible to this disease. Muscle lesions are often more severe. So many people are confused to diagnose it as IBD, because muscle lesions can be caused by many diseases, CAV, IBH, HPAI, Leuco.
See picture below, this male chicken layer breed. In broilers, we rarely encounter more severe muscle lesions than lesions on the bursa. In the breed layer, we can find severe lesions, may need further research, to see susceptibility of IBD virus to various breeds of chicken.
picture below, young female chicken.
Try to compare the lesions of the bursa of Fabricius of chicken numbers 1 and 2.
If we only look at lesions on the bursa of Fabricius to diagnose IBD, this becomes biased, because vvND and HPAI also cause similar lesions. This is the subject of discussion for veterinary students in the classroom.