[Association between amino acid sequences in peptide binding region [BOLA-DRB3] and susceptibility or resistance to calf diarrhea]

The major histocompatibility complex genes [mhc] encode MHC I and II molecules which present peptide fragments to T cells. Therefore these polymorphic molecules critically influence susceptibility to infectious diseases. At present study potential relationship between amino acid sequences in the antigen binding groove of different BoLA-DRB3 alleles and susceptibility or resistance to calf diarrhea was investigated. Twelve different DRB3 alleles were found among 171 calves [84 diarrheic and 87 healthy] analyesd by PCR-RFLP method. Amino acid sequences of the encoded peptide binding region were compared. 26 polymorphic positions were detected in this region. A significant association [p<0.05] was shown between occurrence of diarrhea and the presence of glutamic acid and tyrosine inpocket 4 and valine, glutamine and leucine in pocket 9 of peptide binding region. Thus it can be concluded that pockets 4 and 9 of the BoLA-DRB3 molecule would be involved in conferring susceptibility of calf to diarrhea

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

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 [0.01

[ distribution of Vibrio cholerae from the surface waters of Golestan province]

Vibrio species are oxidase positive, gram negative bacilli that predominantly reside in surface waters such as lakes, rivers. They cause predominantly intestinal diseases as well as a few extra-intestinal complications. Vibrio-related diseases often rise during natural disasters such as floods. Vibrio cholerae cause cholera in humans. In this study, the occurance of Vibrio cholerae in the surface waters of Golestan province, was investigated. The APW and TCBS agar culture media were used for primary isolation of Vibrio cholerae and the exact species identification were done by performing the following tests; oxidase reaction, growth in 0%, 1%, 3%, 6% salt solution, lysine and ornithine decarboxylase, Arginine dehydrolase, ONPG and VP test, simmon citrate, bile esculin, indole, CAMP reaction, string test and specific antisera to V.cholerae 01. to confirm the findings, the special antiserum Ogawa and Inaba, were used. We were able to isolate 42 Vibrio spp. from a total of 54 water samples collected. The species included 35 non-01 V.cholerae [84.2%], 2 V.mimicus [2.63%] and 5 V.cholerae 01 [13.1%] isolat. This study confirmed the existence of Vibrio cholerae 01 in 70% of samples from surface waters of Golestan province