Calf mortality is one of important problems of calf rearing in dairy farms worldwide. Besides, several noninfectious factors, such as management around birth, colostrum management, calf housing, feeding system, hygiene and pathogens, play an important role in calf rearing. The aim of the study was to show the most common causes of mortality of calves up to 90 d of their lives. Some data are ava...

Aim: Monitoring was performed in order to determine the Selenium (Se) status of cattle herds in different agricultural areas in Wallonia (Belgium). Materials and Methods: The study included 114 heifers and 184 cows (82 dairy and 102 beef cows) from 66 cattle farms situated in Wallonia. The Se status was assessed by measuring the glutathion peroxydase in red cells and converting it to the equiva...

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 examined the use of PGF(2α) and estradiol benzoate (EB) either with or without GnRH to synchronize estrus in dairy cows for timed artificial insemination (TAI) under field conditions. First, Holstein dairy cows with a corpus luteum (CL) received 500 μg cloprostenol and were then randomly allocated to three groups: no further treatment (control, n=236); treatment with 1 mg EB 56 h aft...

BACKGROUND The dairy industry has undergone substantial structural changes as intensive farming has developed during recent decades. Mastitis continues to be the most common production disease of dairy cows. Nationwide surveys of mastitis prevalence are useful in monitoring udder health of dairy herds and to study the impact of structural changes on the dairy industry. This survey on bovine sub...

postpartum anestrous is one of the most important problems in the dairy industry in the world and especially in iran. the objective of present study was to compare the efficacy of two hormonal programs for recycling of postpartum anestrous cows. for this reason, 230 holstein cows from 4 similar dairy herds (with totally 2560 cow and unique management and feeding system) located on the suburb of...

Breed differences and nonadditive genetic effects for milk production traits, somatic cell score (SCS), conception rate (CR), and days to first service (DFS) were estimated for Holstein × Montbéliarde and Holstein × Normande crossbreds, using an animal model adapted from the French genetic evaluation and extended to across-breed analysis. Inbreeding and breed differences were estimated from all...

BACKGROUND Eradication of bovine tuberculosis (bTB) through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12 year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient...

The decline of dairy cattle fertility worldwide remains a major concern, with conception rates to first service commonly below 40%. The length and severity of negative energy balance postpartum are unfavorably correlated with fertility, suggesting that the length and severity of negative energy balance and fertility are linked via several hormones or metabolites. These compounds therefore have ...

Introduction: Although milk production as measured by rolling herd averages has increased markedly for dairy herds in the Western United States over the last decade, reproductive performance of these herds has declined significantly. Average days open have increased by 25 days and fertility has declined as measured by an increase of 0.37 services per conception and first service conception rate...