the present study investigates the gap between the daily milk production potential and the effective milk yields in six herds. these two parameters and their changes were observed in the gharb irrigation scheme (northwest of morocco), during a five months study period. they were analyzed in relation to the changes in the rations of the cows and in their live weights. results reveal that under c...

The advent of biotechnology has made data on undomesticated mammals relevant to dairy science. Such data indicate the potential of lactation for modification, reveal genetic material available for use through bioengineering, help distinguish adaptive features from historical artifacts, and clarify limits on lactational diversity that date from early evolution. Evolutionary analysis indicates th...

In early lactation, susceptibility to disease is greatest, impacting cow health and productivity and leading to economic losses. Mastitis is the most economically costly disease to the dairy industry and is most frequent at this time. The objective of this paper is to discuss the energetic fuels used by leukocytes in the metabolic response during mastitis that may reveal potential mechanisms li...

determination of milk yield potential using an accurate method is essential for assessing nutritional requirements, evaluation of genetic potential, lamb growth and survival, management decisions and improving performance traits of sheep flocks. exogenous oxytocin injection is applied to estimate milk secretion rate in sheep. oxytocin is a neurohormone produced in the hypothalamo-neurohypophysi...

Early lactation parameters are difficult to estimate from commercial dairy records due to the small number of records available before the peak of production. A biological model of lactation was used with weekly milk records from a single Holstein herd to estimate these early lactation parameters and the secretion rate of milk from the average cell throughout lactation. A genetic analysis of th...

The objective of this study was to investigate the effect of inbreeding on lactation performance in Holstein cows of Iran.The pedigree file contained information of 1,025,281 animals born between 1965 and 2007.Lactation performance records from March 2000 to April 2009 comprising 193,501calving events on 123,751 cows in 85 dairy herds were included in the data set. The potential consequent effe...

Determination of milk yield potential using an accurate method is essential for assessing nutritional requirements, evaluation of genetic potential, lamb growth and survival, management decisions and improving performance traits of sheep flocks. Exogenous oxytocin injection is applied to estimate milk secretion rate in sheep. Oxytocin is a neurohormone produced in the hypothalamo-neurohypophysi...

the objective of this study was to investigate the effect of inbreeding on lactation performance in holstein cows of iran.the pedigree file contained information of 1,025,281 animals born between 1965 and 2007.lactation performance records from march 2000 to april 2009 comprising 193,501calving events on 123,751 cows in 85 dairy herds were included in the data set. the potential consequent effe...

The objectives were to determine the effect of administering recombinant bovine ST (bST) every 14 d on milk yield and milk composition in dairy ewes and to assess the possible effects of treatment on milk yield loss that occurs at lamb weaning. Seventy-two lactating dairy ewes were separated into 4 groups at lambing, and each group received no bST (control) or 40, 80, or 120 mg of bST every 14 ...