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Selection for genetically superior Murrah buffaloes under Network Project on Buffalo Improvement, India, is presently based on milk yield, and it was observed that even in the absence of any direct selection pressure applied on fertility, there has been a downward trend in fertility associated with the selection for milk yield. The aim of the study was to develop selection indices which include fertility besides milk yield in Murrah buffaloes. Data pertaining to 1,224 lactation records spread over a period of 19 years were recorded and analyzed in the study. The negative association of pregnancy rate (fertility) with a 305-day milk yield (−0.08 ± 0.04) and wet average (−0.12 ± 0.02) indicated the importance of incorporating fertility trait in the construction of selection index. Four types of selection indices were constructed and evaluated. Two indices were developed using expected producing ability 305-days milk yield (EPAMY) with 6.5 and 4 % fat in milk along with expected fertilizing ability (EFA). The other two indices developed consist of expected producing ability wet average (EPA WA) and EFA. The index involving (EPA WA and EFA) was found to be a more effective selection criterion in our herd, as the accuracy of index was more (0.61), in comparison to the index involving EPA MY and EFA. The robustness of selection index was assessed by increasing the relative economic values of included traits by 25 and 50 %, and accuracy of the index remains almost stable without much change. The developed selection strategy involving EPA WA and EFA should be considered for the genetic evaluation of Murrah buffaloes, as it has a potential for maximizing the lifetime reproduction and production performances of the breed.

The present investigation was carried out to study the prevalence of mastitis in 136 Holstein cows from a subtropical province of South Korea. Out of 527 milk samples studied, 22.6 % were found positive for mastitis. On animal level, prevalence was estimated at 55.2 %. Late lactating cows were at higher risk for mastitis development as compared to those in early and mid lactations. The study revealed that the risk of an increase in somatic cell count (SSC) and mastitis increased with advanced age and in animals with higher parity. The highest infection rate of 71.4 % was found in the age group >9 years followed by cows with higher than fifth parity (65.5 %). On severity and quarter basis, cows of

Lactoferrin, a protein found in variety of body secretions, acts as a defense factor in the mammary gland. Total of 50 samples of blood and milk of Jersey crossbred cattle were collected from the Government Dairy Cattle farm, Belicharana. Genomic DNA was isolated and specific primer was used for the amplification of the promoter region of lactoferrin gene. The PCR product comprised of 115 bp. The PCR product was digested with Taq I restriction enzyme. The amplicon has no restriction site and all the 50 animals revealed only one type of genotype (HH) with respect to Taq I / PCR-RFLP. The same PCR products were subjected to SSCP. Amplicons were initially denatured with denaturing agents and then run on native PAGE which was later silver stained. All the 50 samples revealed one type of banding pattern viz., two bands. Single genotype was present in all animals. Hence promoter region of Lactoferrin gene is monomorphic in crossbred cattle under the present study. Somatic cell count was done by staining milk samples with Newmans stain. A total of 19 milk samples had somatic cell count of less than 1,00000 cells/ml with no history of mastitis were considered as resistant, while other 20 samples having somatic cell count more than 5,00000 cells/ml with mastitis were considered as susceptible. Though variation in response to mastitis resistance was detected, no association was established. The reason being that promoter region of lactoferrin gene was monomorphic with respect to Taq I / PCR-RFLP and PCR-SSCP.

Present study was aimed to discover the single nucleotide variation present in exon 40 region of the Fatty Acid Synthase (FASN) gene. FASN plays a central role in de novo lipogenesis in mammals and variation in this enzyme may affect economic traits including fatty acid composition of buffalo milk. A total of 80 DNA samples in two riverine buffalo breeds namely, Gojri and Chhattisgarhi were screened using Restriction Fragment Length Polymorphism (RFLP). FASN gene was found to be polymorphic with an adenine to guanine transition. Three types of genotypes, viz. AA, AG and GG were observed in the studied breeds. Allele A was found to be more frequent than G allele. All the genotypes showed almost the same frequency across the breeds, indicating that there is absence of selection for FASN gene in lesser known buffalo breeds of India. The study will augment the information available and can be applied in future studies to determine the role of bovine FASN gene as a candidate gene marker for a milk-fat content.

Alpha-lactalbumin (alpha-LA) is a major whey protein found in milk. Polymorphs of alpha-LA gene are reported to be significantly associated with milk production and constituent traits. Therefore, the present study was undertaken to detect polymorphism in alpha-LA at the genic level and to explore allelic variability at this locus. A total of 196 animals, belonging to four breeds of riverine buffalo viz. Bhadwari, Mehsana, Surti and Murrah were included under the present investigation. Two fragments i.e. 133 bp (Exon 1) and 159 bp (Exon 2) of alpha-LA gene were amplified by polymerase chain reaction and subsequently, single strand confirmation polymorphism (SSCP) study was carried out to identify different allelic pattern and genotypes of the animal included in the study. Both fragment of alpha-LA gene was found to be polymorphic in all the four breeds of riverine buffalo. Number of genotypes and allele varied breed to breed for both the fragments. In case of 133 bp fragment, four alleles A, B, C and D were found among different breeds of buffalo whereas in 159 bp fragment, five alleles namely A, B, C, D and E was found in different breeds. Nucleotide sequence data of different alleles showed the presence of both silent as well as functional mutation leading to variability in polypeptide chain.

A study was carried out to determine genetic variants of β-lactoglobulin gene and to explore associations between these and milk composition traits in riverine buffalo. Single strand conformation polymorphism was employed to detect the genetic variants of the gene. Two fragments of this gene i.e. 119 bp of exon I and 400 bp spanning exon IV and intron IV were included in the study. For 119 bp fragment, three alleles namely, A, B and C were observed in all the buffalo breeds whereas four alleles (A, B, C and D) were detected for 400 bp fragment. The frequency distribution of alleles was different in different breeds of buffaloes for both the fragments. For exon I fragment, the milk composition traits such as total SNF, protein, solid, fat and whey protein yield were found to be significantly (PPP