The efficient production of milk drives the profitability of the dairy enterprise. Within a dairy herd, total milk production is determined by the proportion of cows producing milk at any given time and the level of milk production of the individual cows within the herd (Vandehaar, 1998). Both of these factors are dramatically affected by reproductive efficiency. Improving reproductive efficien...

bovine viral diarrhea virus (bvdv) is a pestivirus of the flaviviviridaefamily that infects cattle, and its widespread distribution can cause substantial economic losses worldwide. the aims of this study were: (1) to estimate the prevalence of animals persistently infected (pi) with bvdv in industrial dairy cattle herds in suburb of mashhad- iran; and (2) to compare the occurrence of persistent...

BACKGROUND The aim of this study was to detect the associations between bovine herpesvirus 1 (BHV-1) status of a herd and respiratory disease (BRD) occurrence and reproductive performance in pregnant heifers and cows. The association between management-related factors and higher BRD occurrence was also estimated. METHODS Serum samples, collected from cows and youngstock from 103 dairy cattle ...

BACKGROUND Staphylococcus aureus is a common udder pathogen in dairy cows, and may cause severe mastitis problems in some herds. In herds where normal control measures are not successful, vaccination might be an additional tool to use if sufficiently efficient. The aim of the present study was to evaluate the efficacy of a commercially available vaccine (Startvac(®), Hipra, Spain) in two commer...

An important branch of the modern global economy is food production. Our focus is milk production on dairy farms, the period in which cows produce milk (lactation) and the quantity of milk produced. Special attention will be given to the time-dependent function that describes the quantity of the milk produced over a lactation period. The respective graph is known as the lactation curve and is o...

The objective of this study was to determine the effect of rain tree pod meal with palm oil supplementation on feed intake, digestibility, microbial protein synthesis and microbial populations in dairy cows. Four, multiparous early-lactation Holstein-Friesian crossbred (75%) lactating dairy cows with an initial body weight (BW) of 405±40 kg and 36±8 DIM were randomly assigned to receive dietary...

Heat stress (HS) negatively affects various industries that rely on animal husbandry, particularly the dairy industry. A better understanding of metabolic responses in HS dairy cows is necessary to elucidate the physiological mechanisms of HS and offer a new perspective for future research. In this paper, we review the current knowledge of responses of body metabolism (lipid, carbohydrate, and ...

The dairy industry in North America has changed dramatically with a trend in direction of larger herds and higher production per cow, which seems to be associated with a decrease in fertility, especially a decrease in conception rates and extension of calving intervals (Butler, 2000; Lucy, 2001; Stevenson, 2001) This decline in fertility of lactating dairy cows is observed not only in North Ame...