The objectives of this study were to compare the effects of post-ruminal and intravenous infusions of wheat starch or glucose (CHO) or a mixture of amino acids (AA) on milk protein yield, nitrogen (N) utilisation, plasma metabolites and mammary extraction rate of dairy cows in late lactation. Eight cow, ruminally fistulated, was assigned to two 4 × 4 Latin squares during 14-day periods, where t...

The aim of the present study was to compare the occurrence and duration of clinical mastitis in different seasons, stages of lactation period and parities in a Holstein dairy farm in Iran. A retrospective epidemiological survey from April 2005 to March 2008 was conducted on 884 clinical mastitis cases of 7437 lactations. Data of each case including calendar-date of mastitis onset, days in milk ...

Farmers' subjective evaluations of their cows' milking speed, scored as "very fast", "fast", "average", "slow", or "very slow", were recorded between 1982 and 1985 under Agriculture Canada's Record of Performance milk recording scheme. For the analysis, scores taken at the beginning (score 1) and the end (score 2) of the lactation were distinguished. Edited data comprised 20,909 records for sco...

Lactation is a continuation of intrauterine gestation. In both processes, maternal diet plays an active role in the provision of nutrients, maternal nutritional stores and endocrine adaptations serve to buffer the short-term variations in maternal flutritional intake, blood flow plays an overriding role in nutrient transfer to the fetus and newborn infant, and the nutrient demands of the recipi...

The influences of age and lactational period on the distribution, number and structure of somatomammotrophs (SMTs) and the relationships to changes in somatotroph and lactotroph populations in ovine were studied using immunocytochemical procedures with light and electron microscopy as well as morphometric techniques. Adenohypophyseal glands of 15 individuals of the Segureña bread (female lambs ...

Lactation is a continuation of intrauterine gestation. In both processes, maternal diet plays an active role in the provision of nutrients, maternal nutritional stores and endocrine adaptations serve to buffer the short-term variations in maternal flutritional intake, blood flow plays an overriding role in nutrient transfer to the fetus and newborn infant, and the nutrient demands of the recipi...

The objective of this study was to investigate the phenotypic relationship between common health disorders in dairy cows and lactation persistency, uncorrelated with 305-d yield. The relationships with peak yield and days in milk (DIM) at peak were also studied. Daily milk weights and treatment incidence records of 991 Holstein lactations from experimental dairy herds at Virginia Tech and Penns...

The main objective of this experiment was to study the γ-glutamyl transferase (GGT) activity in milk during lactation and its relationship with metabolic status of dairy cows, milk yield, milk composition, and cheesemaking properties. The study was performed in a tied stall barn and involved 20 lactations from 12 healthy multiparous Italian Friesian dairy cows. During lactation starting at d 10...

the purpose of this study was to determine the effects of feeding iron-deficient diet during pregnancy and lactation on maternal rats. a total number of 64 rats were divided into 4 groups (pregnant), (non pregnant), (lactating) and (non lactating) with 16 animals in each group. parameters used to evaluate the effects of dietary iron deficiency on the maternal animals were: iron contents of live...

the objective of this study was to estimates the genetic and environmental components for the lactation curve parameters, milk yield, age at first calving (afc), calving interval (ci) and somatic cell count (scc) in iranian holstein cows. the dataset consisted of 210625 test day records from 25883 cows with milk yield in the first parity recorded from july 2002 to september 2007 in a total of 9...