For several mammalian species, it has been shown that fetal and early postnatal nutrition has a role in long-term lipid and glucose metabolism of the offspring, and it thus also may have consequences on milk yield in the dairy cow. For instance, high-energy diets during the last weeks of pregnancy may result in increased glycemia, which in turn, may alter fetal adipose tissue development. Howev...

Using monthly test day records the genetic parameters of Iranian Holstein cattle in first lactation were studied. Data of 277400 test-day milk records from 65320 cows and 2210 sires were analyzed by an animal random regression model using restricted maximum likelihood methodology. The model included herd-test-date, interaction between year-season of calving, days in milk (linear and quadratic) ...

1. Two experiments were carried out with lactating Friesian cows with a potential for high milk production. Within 3 d after calving they were fitted with a catheter to allow infusions to be given into the abomasum. During each experiment the milk yields and intake of the cows were such that they were calculated to be in negative energy balance. 2. In the first experiment three COWS were infuse...

-A feeding trial was conducted in eight cows to compare the effect of supplementing commercial yeast species Saccharomyces cerevisiae and Saccharomyces siccum on milk yield and its composition. Cows were randomly assigned to one of the two treatment groups consisting four animals each. Commecial yeast granules were added at the rate of 25 g /cow / day to the concentrate feed in the afternoon fo...

The study was conducted to assess the effect of milk production, parity, stage of lactation, season and individual milk components themselves on milk urea nitrogen (MUN) concentration and other milk components of 3,219 Holstein dairy cows in Korean dairy farms. The MUN concentrations in Korean dairy cows were estimated to 16.68±5.87 mg/dl. Milk yield was negatively correlated with fat and prote...

Herd differences in value of milk for fluid use, nonfat dry milk, and Cheddar, Swiss, Mozzarella, and cottage cheeses were determined. Data were 1988 herd average fecords from the National Cooperative Dairy Herd Improvement Program that included milk, fat, and protein yields from 50,608 herds (3.8 million cows) that produced 28.8 billion kg of milk Values of annual yield were calculated both on...

The objective of this study was to analyze the correlation between Holstein body conformation traits and milk production traits in the Shanghai region. In total, 871 Holstein cows were randomly chosen from 28 dairy farms in Shanghai at second stage of lactation as the object of our study. Five milk production traits, including 305-d milk yield, butter fat percentage, milk protein percentage, pe...

The objective of the present study was to investigate single nucleotide polymorphisms (SNPs) located in three candidate genes previously reported to have effects on fertility and milk production traits in a population of 123 Holstein cows. The milk production traits evaluated included lifetime averages of milk yield, protein concentration, and fat concentration. Fertility traits evaluated inclu...

The aim of this study was to evaluate the effect of fat supplementation for enhancing milk conjugated linoleic acid (CLA) in early lactation without affecting ruminal fermentation. 24 Holstein dairy cows were assigned to a completely randomized design employing a 2 × 4 factorial arrangement. Factors were particle size (15 and 25 mm) and two different sources of alfalfa supplemented with and wit...

Bulk tank milk from 28 dairy farms was sampled every second month for 2 yr to assess the effects of grassland management, production system and season on milk fatty acid (FA) composition, concentrations of fat-soluble vitamins, Se, and milk sensory quality. Grassland management varied in terms of time since establishment. Short-term grassland management (SG) was defined as establishment or rese...