PATHOLOGICAL AND MOLECULAR DIAGNOSIS OF INFECTIOUS BURSAL DISEASE IN COMMERCIAL CHICKEN
| dc.contributor.advisor | SATHEESH, K (MAJOR) | |
| dc.contributor.advisor | SAMATHA, V | |
| dc.contributor.advisor | SRINIVASA RAO, T | |
| dc.contributor.author | AKHILA, N | |
| dc.date.accessioned | 2022-10-19T08:21:33Z | |
| dc.date.available | 2022-10-19T08:21:33Z | |
| dc.date.issued | 2022-03 | |
| dc.description | THESES | en_US |
| dc.description.abstract | The present study was undertaken to know the occurrence of IBD in commercial chicken in around Vijayawada and to carry out pathological and molecular diagnosis of IBD. In the present study, a total of 922 IBD suspected birds of 4 to 6 weeks age were procured from different places in and around Vijayawada, from private diagnostic laboratories besides postmortems conducted in NTR College of Veterinary Science, Gannavaram. At necropsy, IBD was diagnosed in 252 birds out of 922 screened with an overall occurrence of 27.33% based on pathological lesions and molecular detection of IBDV by RT-PCR. The disease was more prevalent in 4 to 6 weeks aged birds with majority of cases occurring during the 5th week (40.11%). The occurrence was highest in April to September months (31 to 40%). As per the history, the affected birds showed depression, watery diarrhoea (white to yellowish), soiled vents, anorexia, ruffled feathers, reluctance to move, closed eyes and death. Necropsy conducted in 252 birds revealed predominant gross lesions in the bursa of Fabricius, spleen, thymus, caecal tonsils. Petechiae and ecchymoses on the pectoral and thigh muscles, haemorrhages at the proventriculus-gizzard junction. Bursa was swollen and oedematous with creamy or yellowish discoloration, gelatinous exudates in the serosa, congestion and haemorrhages on the serosal and mucosal surfaces and inner surface of longitudinal laminae in almost all the cases. Occasionally, the bursa became atrophied and whitish or creamy, which sometimes contained cheesy mass in the lumen. The spleen was enlarged and mottled. Kidneys were markedly swollen, congested and liver was enlarged, friable and yellowish in few cases. Histopathology revealed the prominent findings in bursa of Fabricius, characterized by congestion and hemorrhages along with lymphoid depletion of various degrees in the follicles resulting in atrophy of follicles and formation of cystic spaces within the follicles. Presence of eosinophilic necrotic material in the bursal follicles along with degenerating heterophils, atrophy of plicae, widening of interfollicular spaces with proliferation of fibrous connective tissue and sloughing of bursal epithelium was observed in few cases. Microscopic examination of spleen depicted congestion of splenic vessels and sinusoids, depletion of lymphocytes of varying degrees in white pulp and germinal centers. Thymus revealed decrease in thymocyte density in the cortex and congestion in most of the cases. However, in some cases disruption of normal architecture of cortex and medulla was also evident. Lymphoid depletion in lymphoid nodules, mucosal necrosis along with infiltration of mononuclear cells in the lamina propria were noticed in caecal tonsils in majority of the cases. Kidneys revealed interstitial haemorrhages and congestion in peritubular capillaries, severe infiltration of inflammatory cells, degeneration and individualization of tubular epithelial cells with detachment from the basement membrane and glomerular shrinkage. Liver revealed haemorrhage and severe necrosis of hepatocytes, congestion in the central vein, fatty change in hepatic parenchyma, diffuse coagulative necrosis of hepatocytes, along with severe infiltration of mononuclear cells in the portal areas of the liver. In the present study, pooled bursal samples were collected from 33 birds and utilized for molecular diagnosis of by RT-PCR using specific primers targeting VP2 gene of IBDV. Electrophoretic analysis revealed an amplified product of 480 bp fragment of VP2 gene in 9 samples thus confirming the presence of IBDV. The nucleotide sequencing and phylogenetic analysis of present IBDV sample (OM2024620) revealed it’s close relation with the strains of Kerala (MK 861022.1), Gujarat (AB605259.1), Karnataka (EU788042.1) and Haryana (AY739668.1). In the present study, the pathological and molecular diagnosis of IBD was carried out and the occurrence of IBD in commercial chicken in and around Vijayawada was recorded. It was evident that IBD continues to be a major threat causing economic losses in chicken in the study area | en_US |
| dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810189176 | |
| dc.keywords | PATHOLOGICAL; MOLECULAR DIAGNOSIS; INFECTIOUS; BURSAL DISEASE; COMMERCIAL CHICKEN | en_US |
| dc.language.iso | English | en_US |
| dc.pages | 135 | en_US |
| dc.publisher | SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA | en_US |
| dc.sub | Veterinary Pathology | en_US |
| dc.theme | PATHOLOGICAL AND MOLECULAR DIAGNOSIS OF INFECTIOUS BURSAL DISEASE IN COMMERCIAL CHICKEN | en_US |
| dc.these.type | M.V.Sc. | en_US |
| dc.title | PATHOLOGICAL AND MOLECULAR DIAGNOSIS OF INFECTIOUS BURSAL DISEASE IN COMMERCIAL CHICKEN | en_US |
| dc.type | Thesis | en_US |