نتایج جستجو برای: calving year
تعداد نتایج: 596348 فیلتر نتایج به سال:
The effect of calving ease on the fertility and production performance of both dam and calf was studied in approximately 50,000 and 10,000 UK Holstein-Friesian heifers and heifer calves, respectively. The first objective of this study was to estimate the effect of a difficult calving on the subsequent first-lactation milk production by estimating lactation curves using cubic splines. This metho...
Calving of icebergs is an important component of mass loss from the polar ice sheets and glaciers in many parts of the world. Calving rates can increase dramatically in response to increases in velocity and/or retreat of the glaciermargin, with important implications for sea level change. Despite their importance, calving and related dynamic processes are poorly represented in the current gener...
AIM The present investigation was undertaken to study the reproduction performance and effect of non-genetic factors on reproduction performance of Jersey crossbred cows. MATERIALS AND METHODS Data on 355 Jersey crossbred cattle maintained at the Post-graduate Research Institute in Animal Sciences, Kattupakkam, Tamil Nadu, distributed over 30 years (1985 to 2014). The effect of various non-ge...
A total of 25,471 Iranian Holstein heifers distributed in 523 herds of 20 provinces were used to estimate heritability, genetic and phenotypic associations between a number of traits related to the production and reproduction performance. The Animal Breeding Centre of Iran collected the records studied in this research between 1991 and 2001. The traits associated with production were 305-day, 2...
A bioeconomic computer model was used to evaluate alternate calving seasons in a cow-calf enterprise under range conditions representative of the Northern Great Plains. The simulated ranch utilized a rotational breeding system based on Hereford and Angus and had a fixed forage base (4,500 animal unit months of native range, 520 t of grass hay, and 183 t of alfalfa hay). Calving seasons studied ...
A total of 179,460 monthly test-day milk records (thrice a day milking) obtained from 17,946 Iranian Holstein heifers distributed in 287 herds and calved from 1986 to 2001 were used to predict breeding value of animals. Monthly test-day milk production was analysed by applying a covariance function in which the effects of herd-year-season of production (HYSOP), age at test day (covariate), addi...
Calving is a key event on any cattle farm, with both economic and animal welfare consequences when complications arise. Although mostly reported in highly selected breeds, problematic calving performance is also a worry to the unselected dualpurpose Murboden breed, local to Austria. Th is study presents genetic parameter estimates for calving ease and stillbirth in Murboden cattle. Furthermore,...
The impact of varied calving and weaning times on post-weaning production of steer calves was evaluated in a 3yr study. Steers (approximately 12 steers per calving-weaning treatment per year) born in late winter or early spring were weaned at 190 or 240 d of age, and steers born in late spring were weaned at 140 or 190 d of age after grazing with their dams on native range. Steers were pen-fed ...
Dried distillers grains plus solubles (DDGS) contain fat and rumen undegradable intake protein, both of which have been shown to increase reproductive performance in heifers. The mechanisms leading to enhanced reproduction have not been fully defined. The objectives of this research were to evaluate effects of DDGS in late gestation heifer diets on animal and reproductive performance and on blo...
The objectives of this study were 1) to detect quantitative trait loci (QTL) affecting direct and maternal calving traits at first calving in the Danish Holstein population, 2) to distinguish between pleiotropic and linked QTL for chromosome regions affecting more than one trait, and 3) to detect QTL affecting stillbirth and calving difficulties but not calf size that could be used in selection...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید