The objective of this study was to evaluate the effect of ruminally protected amino acids (RPAAs) and ruminally protected fat (RPF) supplementation on ruminal fermentation characteristics (in vitro) and milk yield and milk composition (in vivo). Fourteen mid-lactating Holstein dairy cows (mean weight 653±62.59 kg) were divided into two groups according to mean milk yield and number of days of p...

OBJECTIVE A meta-analysis was conducted to evaluate the effects of supplemental fat containing saturated free fatty acids (FA) on milk performance of Holstein dairy cows. METHODS A database was developed from 21 studies published between 1991 and 2016 that included 502 dairy cows and a total of 29 to 30 comparisons between dietary treatment and control without fat supplementation. Only satura...

To evaluate lactation performance and changes in plasma and fecal lipopolysaccharide (LPS) concentrations in response to the supplementation of Saccharomyces cerevisiae fermentation product (SC), two dairy farms were selected. On each farm, 32 cows in early to mid lactation (21 to 140 DIM) were blocked by parity and days in milk (DIM), and randomly assigned to one of the two treatments within b...

Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight) were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets wit...

Twenty-five crossbred gilts were used in an experiment to determine the tryptophan (Trp) requirement for reproduction. L-tryptophan was added to a fortified corn-gelatin diet to attain the five Trp levels of .64, 1.04, 1.44, 1.84 and 2.24 g per day. These diets were fed at 2 kg daily during pregnancy I and 1.82 kg daily during pregnancies II and III. During each 3-week lactation, all animals we...

The aim of this study was to examine the expression patterns of SREBP-1 gene in milk somatic cells and its association with milk fat yield during early lactation in Sarda breed sheep. A sample of 20 Sarda ewes, aged between 4 and 5 years, in their third to fourth lactation were chosen. From each ewe 28 days after lambing milk yield was measured, and a 160 ml milk sample for the RNA extraction a...

Sixty sows were individually penned in a thermoneutral (20~ or hyperthermal (32~ environment and fed a basal (corn-soybean meal), high-fiber (48.5% wheat bran) or high-fat (10.6% choice white grease) diet from d 100 of gestation through a 22-d lactation. The diets were determined to contain 3.28, 2.76 and 3.75 Meal ME/kg, respectively. All pigs received 8.0 Meal of ME and 17.5 g of lysine daily...

The aim of this study was to investigate the effect of diets containing roasted soybean (R), extruded soybean (E) or their combination (RE) on dairy cow performance and milk fatty acid (FA) profile. Nine multiparous lactating Holstein cows (680 ± 25 kg BW; 90 ± 10 DIM; means ± SD) were randomly assigned to a triple 3 × 3 Latin square design. Dry matter intake (DMI), apparent nutrient dige...

The objectives were to investigate effects of nutritional plane and Se supply during gestation on yield and nutrient composition of colostrum and milk in first parity ewes. Rambouillet ewe lambs (n = 84, age = 240 ± 17 d, BW = 52.1 ± 6.2 kg) were allocated to 6 treatments in a 2 × 3 factorial array. Factors included Se [adequate Se (ASe, 11.5 µg/kg of BW) or high Se (HSe, 77.0 µg/kg of BW)] ini...

in this research, 272977 test day records collected from 659 herds during years 2001 to 2011 by the iranian animal breeding center were used. in the first section the ability of different models to predict daily milk yield from alternative milk recording was tested. the result showed that a complex model including noon milking time plus the effect of lactation curve of ali and schaeffer functio...