Heritability and correlation among first lactation traits in Holstein Friesian cows at Holeta Bull Dam Station, Ethiopia
نویسندگان
چکیده
منابع مشابه
Reproductive Performance of Friesian-Holstein Cows at Sebele Research Station in South Eastern Botswana
Retrospective data from Sebele Dairy Farm were analysed for reproductive performance of Friesian/Holstein cows. Three hundred records from 1989 to 1995 were used. The herd was zero grazed and the data was analysed for age at first calving (AFC), calf birth weights (BW), calving interval (CI), days open (DO), calving rate (CR), reproductive wastage (RW) and calving difficulty (CD); dystocia, aft...
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In this study, the incomplete gamma function, an exponential function, a mixed-log function and a polynomial function were evaluated to describe the lactation curve in Moroccan Holstein-Friesian dairy cows. Data from 1990 to 1999, comprising 77130 monthly milk yields of 6029 dairy cows in 280 dairy herds, were used. Edits were carried out by considering the lactation length (5 d and
متن کاملHeritability Estimates for First Lactation Milk Yield of Registered and Nonregistered Holstein Cows
Heritabilities of milk yield and fat test were estimated from first lactation records of 196,672 Holstein daughterdam pairs separately for registered and nonregistered cows for four milk yield groups and by years of freshening of the daughter. The model included herdseason and sire of the daughter. Heritability estimates were similar for registered and nonregistered cows averaging about .33 for...
متن کاملGenetic and phenotypic relationships among endocrine and traditional fertility traits and production traits in Holstein-Friesian dairy cows.
The objective of this study was to estimate the heritability of a number of traditional and endocrine fertility traits in addition to d-56 predicted milk yield (MY56), and the genetic and phenotypic correlations between these traits. Various fixed effects such as season, year, herd, lactation number, diet, percentage Holstein (PCH) of the cow, and occurrence of uterine infection (UI), dystocia ...
متن کاملLinearity of heritability of Holstein first-lactation milk production.
The regression of daughter on dam first-lactation milk deviations from herd-mate averages was found to be linear from an analysis of 47,400 Holstein pairs. The linear equation was y=-25 .6 + .210 (x -27.6) and the quadratic equation was y-----25.6 + .208 (x -27.6) + .0000222 (x~-44131.4) with correlation coefficients, .18258 and .18268, respectively. These results suggest that selection respons...
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ژورنال
عنوان ژورنال: International Journal of Livestock Production
سال: 2014
ISSN: 2141-2448
DOI: 10.5897/ijlp2013.0165