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ThesisItem Open Access STUDY OF TRANSITION NUCLEAR PROTEINl AND PROTAMINEl GENES IN GIR CATTLE BY PCR RFLP 1869(JAU, JUNAGADH, 2014-07) Lalwani Deepali Hiteshbhai; Dr. P. H. VataliyaThesisItem Open Access Comparison of Various Mexhods for the Estimation of Breeding Values in Gir Cattle 1674(JAU,JUNAGADH, 2012-11) SWAPNIL GIRISHKUMAR GAJJAR; Dr. P. H. VATALIYAA total of 1257 lactation records of 345 Gir cows sired by 52 Gir bulls maintained at Cattle Breeding Farm, JAU, Junagadh from 1987-2010, were analyzed to compare various sire and cow evaluation methods for lactation milk yield (LMY) (standardized to 305-2X-ME basis and also to SLPY), lactation length (LL) and calving interval (CI). Earlier records (1965- 1985) were also collected to be partly used in some of the methods. Sire evaluation was done using conventional indices (viz. Modified Simple Daughter Average index, Equiparent index, Norton index, Rice index, Tomar index, Corrected Daughter Average index. Contemporary Comparison method and Corrected Contemporary Comparison method), Least Squares method (LS), Best Linear Unbiased Prediction (BLUP) method and Average Information Restricted Maximum Likelihood (AIREML) method. Cow evaluation was done using LS, BLUP and AIREML methods. BLUP and AIREML models were constructed using univariate models, multivariate models (based on first lactation records) and multivariate repeatability models (based on all lactation records) using the three traits in all possible combinations. Criteria for comparison of all the models involved error variances to measure the efficiency of models. Additionally, coefficients of determination (%) i.e. R2 values and coefficients of variation (CV%) were used to measure the accuracy and stability of models, respectively for linear fixed and mixed models (LS, BLUP and AIREML). Among the conventional indices. Modified Simple Daughter Average index (I-l) was the most efficient method for sire evaluation for 305-DMY and LL followed by Corrected Daughter Average index (1-6). Sire rank correlations of breeding values for 305-DMY and LL by I-l and 1-6 were highly significant (P<0.01). For CI, 1-6 was the most efficient method followed by I-1. Among the linear fixed and mixed models, all sire and cow rank correlations of breeding values for the three traits were highly significant (P<0.01) except those with AIREML model (A- 13) which involved 305-DMY and CI. Repeatability AIREML model (A-S) which incorporated SLPY, LL and CI was the most accurate method of evaluation of animals (sire and cow) for LMY followed by AIREML model A-12 which involved 305-DMY and LL. A-12 was found to be most accurate method of evaluation of animals for LL. A-13 was the most accurate method for evaluation of animals for CI. LS was the most stable method for all the three traits. A-12 was the most efficient method for evaluation of animals for LMY and LL. A-S had relatively higher error variance than A-12. Most efficient method of evaluation of animals for CI was A-13. Sire rank correlations of breeding values for the three traits obtained by first lactation models with their respective all lactation models were highly significant (P<0.01) except those with A-13. Use of all lactation records instead of first lactation records lead to 33.17%, 40.48% and 21.67% gain in accuracies; 36.73%, 28.78% and 18.26% gain in stabilities and 21.38%, 37.64% and 26.50% gain in efficiencies for LMY, LL and Cl, respectively. Thus, AIREML repeatability model incorporating 305-DMY and LL is recommended for evaluation of animals for the production traits viz. lactation milk yield and lactation length, and AIREML repeatability model incorporating 305-DMY and CI is recommended for evaluation of animals for calving interval, a reproduction trait.ThesisItem Open Access GENETIC ANALYSIS OF PRODUCTION TRAITS IN GIR CATTLE 1673(JAU,JUNAGADH, 2012-11) NIKHIL SHANTILAL DANGAR; Dr. P. H. VATALIYAThe production and reproduction records on 228 Gir cows with 680 lactations sired by 52 bulls, maintained at Cattle Breeding Farm, Junagadh Agricultural University, Junagadh, for 24 years (1987 - 2010) were studied. The data were analyzed to study the effect of period of calving, season of calving and parity as fixed effect and effect of sire as random effect on the production traits viz., lactation milk yield, 300-days milk yield, peak milk yield, lactation length and dry period, and reproduction traits viz., calving interval and age at first calving. Least squares means for production traits viz., lactation niilk yield, 300-days milk yield, peak milk yield, lactation length and dry period were 2276.60 ± 171.32 kg., 2115.89 ± 129.81 kg., 12.31 ± 0.51 kg., 328.27 ± 12.99 days and 109.81 ± 20.20 days, respectively. Least squares means for reproduction traits viz., calving interval and age at first calving were 456.36 ± 22.06 days and 1568.08 ± 39.82 days respectively. . I JLi|-LJLJi Ji.Ljt The analysis of variance revealed highly significant effect of period of calving on lactation milk yield, 300-days milk yield, peak milk yield, lactation length, dry period and age at first calving. While non-significant effect was observed for calving interval. Season of calving did not affect significantly to all these traits under study, except dry period and animals calving during July- October had shorter dry period as compared to those calving in other seasons. Parity of calving highly significantly affected lactation milk yield, 300-days milk yield, peak milk yield, lactation length, dry period and calving interval and significantly affected age at first calving. Lactation milk yield, 300-days milk yield, peak milk yield, lactation length, dry period and age at first calving had periodic trend. Lactation milk yield, 300-days milk yield and peak milk yield showed a significant drop during 1995-2002 and thereafter showed an increasing trend during 2003 - 2010. The Average lactation milk yield was rise to 2667.02 kg during 2007-10. Age at first calving had increasing periodic trend over the years rising from 1268.33 to 1787.96 days. Appropriate measures should be taken to improve the trait. Lactation milk yield, 300 days milk yield, peak milk yield, lactation length dry period and calving interval are affected by parity. There was significant drop in the lactation milk yield, 300-days milk yield, peak milk yield, lactation length and dry period after eighth parity. High heritability estimates for age at first calving (0.59 ± 0-07) and moderate heritability estimate for lactation milk yield (0.17 ± 0.04) and 300-days milk yield (0.20 ± 0.05) were obtained in present study, indicated more importance of additive genetic variance in phenotypic manifestation of these traits. The lower heritability estimates for rest of the traits viz., peak milk yield (0.11 ± 0.04), lactation length (0.04 ± 0.03), dry period (0.12 ± 0.04) and calving interval (0.06 ± 0.03) were observed in present study. The repeatability estimates for lactation milk yield, 300- days milk yield, peak milk yield, lactation length, dry period and calving interval were found to be 0.45 ± 0.04, 0.38 ± 0.04, 0.21 ± 0.04, 0.37 ± 0.04, 0.32 ± 0.04 and 0.23 ± 0.04 respectively. Highly significant (P<0.01) phenotypic correlations were observed between lactation milk yield and 300 days milk yield, peak milk yield, lactation length which were 0.901 ± 0.015, 0.684 ± 0.095 and 0.74 ± 0.137 respectively. Phenotypic correlations between lactation milk yield and age at first calving, calving interval and dry period were 0.158 i 0.179, 0.338 i 0.283 and -0.155 ± 0.223, respectively, which were non significant (P>0.05). Phenotypic correlations of 300 days milk yield with peak rnilk yield and lactation length were 0.808 ± 0.066 and 0.456 ± 0.209, respectively, which were highly significant (P<0.01). Phenotypic correlations between 300 days milk yield and dry period, cadving interval and age at first calving were nonsignificant (P>0.05) and were -0.183 ± 0.217, 0.171 ± 0.269 and 0.114 ± 0.178, respectively. Phenotypic correlations of peak milk yield with lactation length, calving interval, dry period and age at first calving were non-significant (P>0.05) and were 0.225 ± 0.295, 0.079 ± 0.309, -0.147 ± 0.255 and 0.104 ± 0.200, respectively. Phenotypic correlations between lactation length and dry period, calving interval and age at first calving were non-significant (P>0.05) and were -0.065 ± 0.346, 0.501 ± 0.432 and 0.191 ± 0.234, respectively. Phenotypic correlations of dry period with calving interval was highly significant (P<0.01) and was 0.520 ± 0.178. Phenotypic correlations of dry period with age at first calving was 0.021 ± 0.195, which was non-significant (P>0.05). Genetic correlations of lactation milk yield vj^ith 300 days milk yield, peak milk yield and lactation length were 0.985 ± 0.015, 0.813 ± 0.095 and 0.839 ± 0.137, respectively, which were highly significant (P<0.01). Genetic correlations of lactation milk yield with dry period, calving interval and age at first calving were non-significant (P>0.05) and were -0.454 ± 0.223, - 0.003 ± 0.283 and 0.144 ± 0.179, respectively. Genetic correlations between 300 days milk yield and lactation length and peak milk yield were 0.744 ± 0.209 and 0.868 + 0.066, respectively, which were highly significant (P<0.01). Genetic correlations between 300 days milk yield and calving interval, dry period and age at first calving were non significant (P>0.05) and were -0.100 ± 0.269, -0.472 ± 0.217 and 0.006 ± 0.178, respectively. Genetic correlation of peak milk yield with lactation length was 0.606 ± 0.295, which was highly significant (P<0.01). Genetic correlation of peak milk yield with age at first calving, dry period and calving interval were non-significant (P>0.05) and were 0.069 ± 0.200, -0.382 ± 0.255 and -0.009 ± 0.309, respectively. Genetic correlation between lactation length and dry period, calving interval and age at first calving were -0.518 + 0.346, 0.016 ± 0.432 and 0.752 + 0.234, respectively, which were non-significant (P>0.05). Genetic correlation of dry period with calving interval was 0.712 ± 0.178, which was highly significant (P<0.01). Genetic correlation of dry period with age at first calving was 0.058 ± 0.195, which was non-significant (P>0.05). Environmental correlation of lactation milk yield with 300 days milk yield, peak milk yield, lactation length, dry period, age at first calving and calving interval were 0.795 ± 0.015, 0.606 ±