The aim of this study was to use meta-analysis to identify the enteric methane (CH4) mitigation strategy that reduced CH4 emission without lowering production. To this end, a database initially developed was updated, compiling data from 61 publications (233 experiments) for various observations in dairy cattle on effects of hydrogen sink (H-sink), ionophore, lipid and conc...

one of the most important measures, in order to increase animal products and reduce imports, is the industrialization of animal husbandry units, specially the dairy cattle. the condition of milk production would be improved by this industrialization, which is in the direction of increasing the efficiency of milk production units. the purpose of this study is calculate , the efficiency of the tr...

This study investigated the effects of replacing soybean meal (SM) with canola meal (CM) and decreasing crude protein (‎CP) levels in CM based diets on performance of dairy cows when different sources of processed grains and CM were used. Canola meal was untreated or roasted at 130°C for 30 minutes and grains sources (corn and barley) were either ground or steamed-flaked. Eight Holstein cows (‎...

Milk yield per cow has more than doubled in the previous 40 years and many cows now produce more than 20,000 kg of milk per lactation. The increase in production should be viewed with concern because: i) the increase in milk yield has been accompanied by declining fertility, increasing leg and metabolic problems and declining longevity; ii) there are unfavourable genetic correlations between mi...

background:chronic active adrenocorticotropin hormone (acth) immunization of ewes (with a previous history of immunization) resulted in elevated titres of antibody against acth, which induced a reduction in circulating levels of cortisol. objectives:the aim of the present study was to investigate: a) the influence of active immunization against acth on milk production of the ewe as assessed by ...

this study was carried out to investigate the possibility of prediction the occurrence of heat stress in dairy cows and determination of climate critical periods. the most common indexes for estimation the degree of thermal stress istemperature humidity index (thi). in this study yousef’s thi index (1985)was used to analyze the yearly and monthly effects of temperature and humidity. meteorologi...

Decisive heifer management for improved lactation and reduced dystocia requires a systematic analysis of age, body weight (BW), and average daily gain (ADG) using an adequately large sample size. The objective of this study was to determine effects of BW and age at first breeding and ADG until pregnancy on yields of milk, milk fat, and milk protein in the first lactation and the occurrence of d...

The aim of the present study was to estimate genetic and phenotypic parameters of milk production traits in the first and second lactations of Romanian Simmental dairy cattle. For the estimation of variance, heritability, genetic and phenotypic correlations among milk yield, fat yield, protein yield, and percentages of fat and protein, 3400 first and second lactation records over a period of fi...

The pituitary-specific transcription factor (PIT1) gene is responsible for pituitary development and hormone secreting gene expression in mammals. PIT-1 is studied as a candidate genetic marker for growth, carcass and also for milk yield traits. In dairy farm animals, the principal goal of the selection is the improvement of milk yield and composition. The genes of milk proteins and hormones ar...