The objectives of this study were to determine carbohydrates such as glucose, total protein, lipid parameters, mineral levels in blood; qualitative characteristics fat, SNF, lactose, solids and protein percentages milk; the quantity milk after feeding german maize fodders. Thirty clinically apparently healthy cows selected divided into three homogenous groups. Control group was fed mixed grass,...

Calving records from the Animal Breeding Center of Iran collected from January 1990 to December 2007 and comprising 207 106 first calving events of Holsteins from 2 506 herds were analysed using linear sire models to estimate genetic trends for age at first calving (AFC) and milk traits. Genetic trends were obtained by regressing yearly mean estimates of breeding values on year of birth. In gen...

Thirty-eight lactating dairy cows including 6 ruminally cannulated cows were used in a feeding study to assess effects of feed sources that differed in dietary nonfiber carbohydrate (NFC) composition and ruminal degradability of dietary protein (RDP) on production, ruminal, and plasma measures. The design was a partially balanced, incomplete Latin square with three 21-d periods and a 3 x 2 fact...

Positional, comparative candidate gene analysis and previous quantitative trait loci linkage mapping results were used to search for candidate genes affecting milk production and reproduction traits in dairy cattle. The protease inhibitor (PI) gene was chosen for examination, and 5 single nucleotide polymorphisms were detected in coding regions of the gene by direct sequencing of reverse transc...

In this study test-day records of milk (kg), fat (g), and protein (g) yields, somatic cell score (SCS, cells/ML) collected by Animal Breeding Center of Iran during 2007 and 2009 were used to estimate genetic parameters using random regression model. Models with different order of Legendre polynomials were compared using Bayesian information criterion (BIC).For milk, fat yield and SCS genetic an...

To determine whether insulin exerts an effect on milk fat yield through the direct regulation of milk fat synthesis in the mammary gland, the hyperinsulinemic-euglycemic clamp procedure was performed in lactating goats in the present study. The effects of the hyperinsulinemic-euglycemic clamp on milk yield, milk composition, milk fatty acid yield and the expression levels of mRNAs of milk fat s...

The determination of the main constituents that compose the milk is important in the dairy food industry, for establishing the milk value, for consumers’ information and for quality control. Fat and total protein content of milk, have economic importance because, in most countries, milk trade is based on these components and the somatic cell counts. It has been an attempt for replacing traditio...

PAGE ................................................................. INTRODUCTION 250 Material and methods ........................................................ 251 Variation of butter-fat percentage in Jersey milk with the age when the test was made ........................................................... 252 Analytical constants describing the variation of butter-fat percentage at dif...