introduction small ruminants, especially native breed types, play an important role in livelihoods of a considerable part of human population in the tropics from socio-economic aspects. therefore, integrated attempt in terms of management and genetic improvement to enhance production is of crucial importance. knowledge of genetic variation and co-variation among traits is required for both the ...

The data were collected from 1992 to 2009 in Burri, White Boni and Black Boni sheep maintained at the Regional Research Station in the Central Highlands of Yemen. Data were analyzed to study the effects of environmental and genetic factors on body weight and growth rate from birth to weaning. The least square means for body weights (BW) were 2.54, 2.18 and 2.26 kg for birth; 12.49, 10.58 and 11...

Performance records on 41,184 Red Angus cattle were analyzed and estimates of parameters calculated for absolute growth rate, relative growth rate and restricted selection indices. Heritability estimates for birth weight, 205-d weight, 365-d weight and postweaning gain were .46 +/- .02, .39 +/- .02, .40 +/- .02 and .36 +/- .02, respectively. Heritability estimates for preweaning, postweaning an...