Milk urea nitrogen (MUN) of dairy cows was determined in relation to breed. A total of forty (40) Pabna and red Chittagong dairy cattle each of twenty (20) were selected to know the milk composition, nutritional status and milk urea nitrogen. Live weight of Pabna Cattle (187±14 kg) was higher than that of red Chittagong cattle (174±4 kg). In Pabna cattle milk yield (4.94 kg), minerals (0.15%) a...

When linear programming is used to rank sires on daughter profits, coefficients of input are required for representative daughters of each sire. Within herdyear-season regressions of daughter's actual 305-day milk, fat percent, days open, 2-min milk yield adjusted for total yield, total milking time, and body weight at birth and first calving on sire's proofs for production, conformation, milki...

the aim of the present study was to estimate genetic and phenotypic parameters of milk production traits in the first and second lactations of romanian simmental dairy cattle. for the estimation of variance, heritability, genetic and phenotypic correlations among milk yield, fat yield, protein yield, and percentages of fat and protein, 3400 first and second lactation records over a period of fi...

Data containing 14,188 lactation and reproductive records of Korean Holstein cows at first parity distributed across 3734 herd-year-season groups were analyzed to get genetic (co)variance estimates for milk yield, fat yield, calving ease, and days open. Milk and Fat yields were adjusted to 305 d. Heritabilities and genetic correlations were estimated in two different animal models on which were...

milk urea nitrogen (mun) of dairy cows was determined in relation to breed. a total of forty (40) pabna and red chittagong dairy cattle each of twenty (20) were selected to know the milk composition, nutritional status and milk urea nitrogen. live weight of pabna cattle (187±14 kg) was higher than that of red chittagong cattle (174±4 kg). in pabna cattle milk yield (4.94 kg), minerals (0.15%) a...

Data containing 14,188 lactation and reproductive records of Korean Holstein cows at first parity distributed across 3,734 herd-year-season groups were analyzed to get genetic (co)variance estimates for milk yield, fat yield, calving ease, and days open. Milk and Fat yields were adjusted to 305 d. Heritabilities and genetic correlations were estimated in two different animal models on which wer...

this study was carried out to investigate the relationship between early lactation curve parameters andcalving interval in holstein cows of iran. in order to describe the lactation curve, the incomplete gammafunction was fitted to 5,754,428 test-day milk records corresponding to 766,108 lactations on 315,634 cowsin 2,448 herds. cows with higher milk yield during early lactation had shorter calv...

Nutrition has a significant effect on reproduction and lactation in Ruminant. Supply of require nutrient of dairy cows and ewes in early lactation is the main challenges that will be considered, since in most cases the animals facing negative energy balance after calving and the beginning of the period of lactation. Negative energy balance may sometimes result in reduced livestock production an...

Estimation of genetic trends is necessary to monitor and evaluate selection programs. The objective of this study was to estimate the genetic trends for milk yield in Iranian Holsteins cows using random regression test day model. Data set was consisted of 743205 test-day records from 1991 to 2008, which were collected by the Animal Breeding Centre of Iran. Breeding, environmental and phenotypic...