The objective of this study was to estimate the breed, heterosis, and recombination effects on different components lactation curve Girolando cattle. dataset used consisted 12,121 purebred cows Holstein (H) Gyr (G) breeds, six H×G crossbred (Girolando). model presents random herd cow, regression coefficient associated with linear effect proportion H heterosis between G [...]

BACKGROUND Changes in colostrum composition of Egyptian buffaloes and Holstein cows collected at calving, 6, 12, 24, 48, 72, 96, 120 h and after 14 days of parturition were studied. Total solids, total protein, whey proteins, fat, lactose and ash contents were determined. Macro- and micro-elements, IgG, IgM, IGF-1, lactoferrin and vitamins (A and E) were also estimated. RESULTS At calving, th...

milk performance (protein and fat content) and milk fatty acids (fa) profile of dairy cows under supplementation with two sources of concentrate, oilseeds (c, cottonseed) at two levels, low (5kg dm/cow/day) and high (7 kg dm/cow/day), and cereal grains (b, barley) at high rate (7 kg dm/cow/day), were studied in three herds (n=36) of spring calving holstein-friesian dairy cows (200 days in milk)...

This study was carried out to evaluate the effects of replacing alfalfa hay with ensiled mixed tomato and apple pomace (EMTAP) on ruminal fermentation and apparent digestibility of diets. Six multiparous Holstein dairy cows in mid lactation were used in 3×3 Latin square design and fed alfalfa hay plus concentrate mixture with three levels replacement with EMTAP (0, 15, 30%) during 63 days. Resu...

A joint sire and cow evaluation for selected type traits has been carried out for the Canadian Holstein population using an individual animal model accounting for all known relationships. Only first lactation, first classification linear records were utilized. Linear scores for final class/final score (combined), feet and legs, mammary system, and stature were analyzed. The model of analysis in...

Sixty-five chromosomal preparations from bisected bovine embryos were examined and 43 embryos (66.2%) with metaphase plates were observed; however, only 25 embryos (38.5%) were sexed. Fifteen of the bisected embryos sexed by chromosomal analysis were transferred to each of the 15 recipients, and 5 recipients became pregnant. Female calves were born on December 28, 1985, August 2, 1986 and July ...

The stress of high milk production, along with increasing herd size and changes in facilities and management, has made fertility one of the main focuses of genetic improvement today. In the US, the reduction in calving rate to first service and the impact of this decrease in fertility on the Holstein breed, mainly in the last 20 years, is of major concern [27]. Figure 1 shows the clear trend fo...

Utilizing pasture-based systems may increase cow comfort during late gestation and calving as it lacks the constraints of confinement housing. The objective of this study was to quantify lying behavior and activity of Holstein dairy cows housed on pasture during the 6 d before calving. Sixteen Holstein dairy cows were moved to pasture 3 weeks before their projected calving date. Data loggers we...

in order to examine the effect of using rumen protected methionine (mepron, evonik industries, hanau, germany) on productive and reproductive performance under field condition, 195 holstein cows were used in a unbalanced completely randomized design and 2 groups. experimental treatments consisted of: 1) control group with 110 holstein dairy cows (71±51 dim and 47.5±12 milk yield) and without me...