The present study was carried on Dahlem Red chicken breed to assess the effect of age on egg quality traits. Total 250 eggs were collected from birds at different age groups, i.e. 21, 28, 40, 52 and 64 weeks of age for studying the external and internal egg quality parameters. The external characters like egg weight, egg length and egg width were measured. Thereafter, the egg was broken and the internal traits like albumen length, height, width of albumen, yolk height, yolk width, shell thickness were recorded using standard procedure. The derived traits like shape index, albumen index, yolk index and Haugh unit, were estimated. Most of the egg quality traits differed significantly at different age of measurements. Egg weight increased as the age of bird advanced and egg weight varied from 39.35±0.69 at 21 week of age to 59.3±1.22 at 64 week of age. Analysis of variance revealed that shape index did not differ significantly with age. Length, width and height of albumen increased as the age of bird progressed. Albumin index was significantly higher at 21 and 40 weeks of age. Similarly, yolk height and width increased as the age of bird advanced. The differences for Haugh unit scores were non-significant among the different age groups and varied within a very narrow range (96.94–98.94) at different ages indicating uniform internal egg quality over the age. Significant differences in shell thickness were observed among different age groups. Correlation coefficient between egg weight with egg length, egg width, albumen length, albumen height and yolk width were positive. Albumen index and Haugh unit were negatively correlated with egg weight at 21, 52 and 64 week of age. The result indicate that the age of bird significantly affects the egg quality parameters.

The present study compared the production performance of DR, Native, DN and DND crosses under intensive system of management. DN and DND crosses showed better growth and production performance compare to local Native parent birds. DND (75% DR inheritance) chicken performed better than DN cross (50% DR inheritance). The better performance of crosses indicated effective utilization and propagation under rural poultry farming system as low input technology birds. It is more beneficial to rear the crosses than local Native birds in Himachal Pradesh. Based on better performance of DND than DN, the former was recommended for development and propagation of Himsamridhi; location specific poultry variety. There is need for wider propagation of these birds in the state by development agencies. Future efforts are required for adaptability assessment of Himsamridhi birds in different agroclimatic region of the state under prevalent village poultry farming system. This will ascertain the suitability of developed cross at farmer’s level.

Lactoferrin gene is one of the important candidate genes for mastitis resistance. The gene is located on chromosome BTA 22 and consists of 17 exons spanning over 34.5 kb of genomic DNA. The present study was undertaken with the objectives to identify allelic variants in exons 7 and 12 of lactoferrin gene and to analyze association between its genetic variants and incidence of clinical mastitis in Murrah buffalo. The amplification of exons 7 and 12 of lactoferrin gene yielded amplicons of 232- and 461-bp sizes. PCR-restriction fragment length polymorphism (RFLP) analysis of 232-bp amplicon using BccI restriction enzyme revealed three genotypes (AA, AB, and BB) with frequencies of 0.62, 0.22, and 0.16, respectively. The frequencies of two alleles, A and B, were estimated as 0.73 and 0.27. Hpy188I-RFLP for 461-bp amplicon revealed polymorphism with three genotypes, CC, CD, and DD, with respective frequencies of 0.06, 0.39, and 0.56, whereas frequencies for C and D alleles were 0.25 and 0.75. The chi-square (χ(2)) analysis revealed a significant association between incidence of clinical mastitis and genetic variants of exon 7, and animals of AA genotype of exon 7 were found to be least susceptible to mastitis. The findings indicate potential scope for incorporation of lactoferrin gene in selection and breeding of Murrah buffaloes for improved genetic resistance to mastitis.

Lactoferrin is one of the important candidate genes for mastitis resistance in dairy animals. The gene is located on chromosome BBU21 and consists of 17 exons spanning over 32.95 kb of genomic DNA. The present study was undertaken to identify allelic variants in exon 8 and 13 of lactoferrin gene and their association with incidence of clinical mastitis in Murrah buffalo. A total of 200 lactating Murrah buffaloes, grouped as mastitis affected and non-affected, were included in the study. Genomic DNA was isolated from the whole blood sample of each animal. Two primer sets were used to amplify exon 8 and 13 of lactoferrin gene, which yielded respective amplicons of 216 bp and 211 bp. The polymerase chain reaction-restriction fragment length polymorphism analysis of lactoferrin gene revealed monomorphic pattern in exon 8 and polymorphic pattern in exon 13. Hpy 188I-RFLP for exon 13 exhibited polymorphism with three genotypes: AA, AB and BB with respective frequencies of 0.20, 0.58 and 0.22 whereas, frequencies for A and B alleles were estimated as 0.49 and 0.51. Comparison of nucleotide sequence of exonic region of lactoferrin gene in Murrah buffalo with that of Bos taurus cattle revealed a total of 5 mutations out of which 2 were transition and 3 were transversion. The SNPs in exon 8 were found to be non synonymous and revealed two amino acid changes in exon 8 of Murrah buffalo as compared to Bos taurus cattle. Chi-square (χ2) analysis indicated non significant association between genetic variants of exon 13 and incidence of clinical mastitis.

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