[ first survey on the status of bovine immunudeficiency virus infection and associated clinical, pathological, haematological and flow cytometric findings in Holestein cattle in Iran]

ABSTRACT

Bovine Immunodeficiency Virus is a Lentivirus which can cause varieties of infectious complications and induce remarkable losses to dairy industry. Considering to the probability of worldwide distribution of the BIV infection, this study was conducted for the first time in Iran to determine of the status of BIV infection in the Holstein cattle and evaluate the associated findings. According to the results of the Nested-PCR method in this study, 16.2% of 197 slaughtered Holstein cattle in Meysam abattoir of Tehran were infective with BIV. Sequencing of the amplicons obtained from PBLs of the cattle using gag-specific primers revealed that there was 98.7-98.9% homology between this field strain and reference sequences of BIV. The infection rate of cattle with enlarged heamal nodes was higher than the animals without these lesions [0.01BIV infection rate and age, sex, BCS, clinical problems or macroscopic lesions and enlarged lymph node as well as the anatomical situation of enlarged heamal nodes. Flow cytometric analysis showed that the relative frequency of CD8+s in the infected animals was significantly lower than the non-infected ones [0.01leukocyte counts, relative frequencies of neutrophil, lymphocyte, CD4+, CD21+, monocyte, eosinophil, hemoglobin and PCV of the infected and non-infected groups. Lymphoid follicular hyperplasia- hypertrophia and in some cases depletion of lymphoid follicules in the lymph and heamal nodes were the main histopathological findings of the infected cattle. The results showed that the BIV infection rate of the surveyed Holstein cattle was relatively high