Sanjeev Ranjan

Association and Expression Analysis of Single Nucleotide Polymorphisms of Partial Tumor Necrosis Factor Alpha Gene with Mastitis in Crossbred Cattle

A total of 129 crossbred cows were selected to explore the genotypic and expression profiling of partial TNF-α gene and its association with mastitis susceptibility. Two exon spanning region of TNF-α gene (221 bp and 239 bp) were amplified by Polymerase Chain Reaction (PCR). The different genotypic analysis by SSCP revealed that 221 bp fragment was monomorphic, whereas 239 bp was polymorphic. Association studies revealed that AA genotypes of 239 bp were more prevalent in mastitis group and the mRNA expression of TNF-α was significantly (P < 0.05) higher in AA genotypic animals compare to AB and BB. This suggested that genotypes AB and BB may be used as candidate markers for mastitis resistance selection in dairy cattle.

Study on Genetic Variation of Microsatellite and Their Association with Mastitis Occurrence in Crossbred Cattle

In present study, the polymorphism at five microsatellite loci BM302, BM4505, BMS2684, CYP21 and DIK20 were investigated for finding their association with the somatic cell counts (SCC) in crossbred cattle. Total 130 animals were tested using california mastitis test (CMT) and somatic cell count (SCC) to screen animals for mastitis. Total 83 alleles were found in all five microsatellites where 23 alleles (9 in BM302, 3 in BM4505, 2 in BMS2684, 8 in CYP21 and 1 in DIK20) were differing significantly in case-control animals. Total number of genotypes for BM302, BM4505, BMS2684, CYP21 and DIK20 were 148, out of which 11 were differing significantly in case-control animals. The allele size ranges for BM302, BM4505, BMS2684, CYP21 and DIK20 were 146 bp to 166 bp, 212 bp to 252 bp, 82 bp to 108 bp, 180 bp to 228 bp and 164 bp to 196 bp, respectively. The polymorphism information content/heterozygosity/allelic diversity for BM302, BM4505, BMS2684, CYP21 and DIK20 were 0.88/0.92/0.89, 0.91/0.53/0.91, 0.81/0.56/0.82, 0.91/0.65/0.92 and 0.82/0.60/0.84. The genotypes ‘146/158’, ‘148/156’, ‘148/158’, ‘150/164’, ‘152/164’, and ‘152/166’ at BM302, ‘238/238’ at BM4505, ‘186/186’ and ‘196/196’ at CYP21 and ‘174/186’ and ‘180/192’ were differing significantly in case-control animals. It revealed that the information observed in the present study was valuable and it may be helpful for improving mastitis resistance in crossbred cattle.

Variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus

A total 290 Black Bengal goats (6 buck, 109 doe and 175 kids born from 11 sires) were studied to evaluate the variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus. The variability of resistance in Black Bengal goat was studied for both genetic and non-genetic factors like village, sex, age dam, sire, dam resistance group and offspring resistance group. Male kids have slightly higher resistance than female kids although it was not significant. Resistance of kids was increased as age increases and kid population showed significantly different resistance status among the offspring resistant groups. The doe population showed significantly different LEPG as per the resistance group in all the collections. The present study found that the resistance of kids under sire were varied significantly and observed that the kids under sire 1, 6–8 were significantly more resistant than the kids of the sire 2, 5 and 11 in 3rd collection and it is also noticed that maternal genetic effect has a very little impact on resistance of kids. Males (buck) were most resistant and the kids were least resistant and the resistance of dam was in between the male and kids population.