Estimation of phenotypic and genetic trends in economic traits of Murrah Buffaloes
2021
Kour, Gurpreet | Narang, Raman | Kashyap, Neeraj | Kaur, Simarjeet | Sodhi, Simrinder Singh
Notable advancements in the selection indices have led to the development of exceptional breeding strategies, which have eventually led to the selection of elite dairy animals. The comparison of trends is facilitated by their estimation which permit the assessment of progress in a particular trait. The purpose of this study was to investigate genetic trends in economic traits of Murrah buffaloes, which is predominantly present as a high milk producer using the regression method. The study was designed to estimate the phenotypic, genetic and environmental trends, which represent the changes accrued over time and hence, determines the efficiency of breeding programme. The present study was conducted on 659 Murrah buffaloes, sired by 188 bulls, over a period of 27 years (1991-2017). The economic traits studied were first lactation milk yield (FLMY), first lactation length (FLL), age at first calving (AFC), first calving interval (FCI), first service period (FSP) and first dry period (FDP). The phenotypic trends were obtained as regression of population performance on year and the genetic trends were obtained by Smith method I and II. The results revealed that the phenotypic trends obtained were significant and desirable for all the traits except for first lactation length, which was non-significant. The standard errors obtained by Smith method-I were higher than those obtained from method-II. As the Smith method-II avoids year to year fluctuations in the environment and those of contemporaries, it gives more realistic estimate as compared to the first method with lower standard error.
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