Allelic diversity of butyrophilin (BTN1A1) gene in Indian bovines

Indian milch bovines comprises of 58.56% of total livestock population (512.05 million) in the country and primarily includes native and crossbred cattle (37.28%) and water buffaloes (21.28%). Milk and milk products are essential food items of Indian diet especially in children, old and senile. Milk fat is an important constituent of milk and has an economic value and its percentage in milk varies betweem species and breeds within species. Butyrophilin (BTN1A1) a membrane protein regulates secretion of lipids and size of a fat globule in milk. Present study was conducted in 538 bovines of 11 breeds/populations adapted to different parts of India, with an aim to screen and determine the major allele of BTN1A1 gene using PCR-RFLP based test. Results indicate that exon 8 of BTN1A1 gene is polymorphic in Tharparkar, Sahiwal, Jhari and Belahi populations of native cattle and Holstein Friesian and Jersey crossbreds where as the same exon was monomorphic in Murrah, Chilika, Gojri, Chhattisgarhi and Bargur populations of water buffalo. We conclude that variations in BTN1A1 gene can serve as an excellent genetic marker while selecting cows for higher milk fat and can be applied while formulating their breeding plans

Investigation of direct and maternal genetic effects on days open in Jersey crossbred cattle

Estimates of (co)variance and genetic parameters for days open (DO) of Jersey crossbred cattle were estimated by restricted maximum likelihood (REML), fitting 6 animal models, including various combinations of maternal effects. Data on 792 records of 223 Jersey crossbred animals, descended from 51 sires and 170 dams were used. The direct heritability estimates for days open ranged from 0.04 to 0.10 depending on the model applied. The additive maternal effects varied from 0.06 to 0.09 in different models in this study, whereas the estimates of the fraction of variance due to maternal permanent environmental effects were practically negligible to very low (0– 4% of the phenotypic variance), irrespective of the models used. Results suggested that direct and maternal additive effects were important for this trait but, the low heritability estimates indicated little scope of genetic progress through selection for this trait

Genetic and environmental causes of variation in gestation length of Jersey crossbred cattle

Aim: The objective of this study was to investigate the effect of genetic and non-genetic factors and estimate the genetic parameter for gestation length (GL) of Jersey crossbred cattle. Materials and Methods: The data included the 986 parturition records on Jersey crossbred cattle maintained at the Eastern Regional Station of ICAR-National Dairy Research Institute, Kalyani, West Bengal, India during 36 years (1978-2013). The data were analyzed applying mixed model least square technique considering the fixed effects of genetic group, season of calving, period of calving, parity of animal, birth weight, and sex of calf born from animal. The effect of sire was included as a random effect in the model. Results: The genetic group of animal, season of calving, parity of animal, and birth weight of calf born were found to be a significant source of variation in the GL, whereas the period of calving and sex of calf did not affect this trait. Cows with 62.5% Jersey inheritance had the shortest and longest GLs, respectively. Cows calved in summer and rainy season had shorter GL than those calved in the winter season. Older cows in 4th parity carried calves for longer days than the cows in 1st parity. The increase in calf birth weight significantly (p<0.01) contributed to a linear increase in GL value in this study. The heritability estimate of GL was 0.24±0.08. Conclusion: It can be concluded that selection for lower GL without distressing future growth of calf can be used to reduce calving difficulty, but a very small standard deviation of GL limits the benefit. Moreover, more accurate prediction of calving date will help in better management and health care of pregnant animals

Influence of FASN gene polymorphism on milk production and its composition traits in Murrah buffaloes

In present study the effect of genetic polymorphism of Fatty acid synthase (FASN) gene on eight traits related to milk production and its composition in 162 Murrah buffaloes was studied. The traits studied includes 305 days milk yield, lactation fat average (LFA), 305 days fat yield (305LFY), lactation solid not fat average (LSA), 305 days solid not fat yield (305LSY), lactation total solid average (LTSA), 305 days total solid yield (305LTSY) and peak yield (PY). Restriction Fragment Length Polymorphism (RFLP) was used to identify the SNP in a 472 bp PCR amplified product of exon-40 in FASN gene. It was found to be polymorphic with Guanine to Adenine transition and three genotypes namely AA, AG and GG were observed. Allele A was found to be more frequent than G allele. We report for the first time that exon-40 FASN gene is associated with LFA, LTSA and peak yield in Murrah buffaloes. This information can augment future studies to determine the role of bovine FASN gene as a candidate gene marker for a milk fat, total solids and peak milk production

Estimates of genetic parameters for fat yield in Murrah buffaloes

Aim: The present study was performed to investigate the effect of genetic and non-genetic factors affecting milk fat yield and to estimate genetic parameters of monthly test day fat yields (MTDFY) and lactation 305-day fat yield (L305FY) in Murrah buffaloes. Materials and Methods: The data on total of 10381 MTDFY records comprising the first four lactations of 470 Murrah buffaloes calved from 1993 to 2014 were assessed. These buffaloes were sired by 75 bulls maintained in an organized farm at ICAR-National Dairy Research Institute, Karnal. Least squares maximum likelihood program was used to estimate genetic and non-genetic parameters. Heritability estimates were obtained using paternal half-sib correlation method. Genetic and phenotypic correlations among MTDFY, and 305-day fat yield were calculated from the analysis of variance and covariance matrix among sire groups. Results: The overall least squares mean of L305FY was found to be 175.74±4.12 kg. The least squares mean of overall MTDFY ranged from 3.33±0.14 kg (TD-11) to 7.06±0.17 kg (TD-3). The h2 estimate of L305FY was found to be 0.33±0.16 in this study. The estimates of phenotypic and genetic correlations between 305-day fat yield and different MTDFY ranged from 0.32 to 0.48 and 0.51 to 0.99, respectively. Conclusions: In this study, all the genetic and non-genetic factors except age at the first calving group, significantly affected the traits under study. The estimates of phenotypic and genetic correlations of MTDFY with 305-day fat yield was generally higher in the MTDFY-5 of lactation suggesting that this TD yields could be used as the selection criteria for early evaluation and selection of Murrah buffaloes