The present study has been conducted to evaluate the effect of intramuscular administration of vitamin A during dry period in pregnant dairy cows which have already received it in their daily ration on vitamin A status of neonatal calves.Single intramuscular injection of 2000000 IU vitamin A was carried in 10 dairy cows at 7 months of pregnancy (group 1) and in another 10 dairy cows at 8 months...

For lactating dairy cows, we need management tools, that are "clean, green and ethical", cost-effective and easy to use. Specific tools are needed for artificial insemination (AI) after oestrus detection within a few months of calving, and for managing the complex nutritional requirements of cows between successive calvings. Assessment of energy deficit by measurement of body condition score (B...

Relative effects of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls on selling price at auction was evaluated during 2008. The presence and severity of 23 BQA-related traits were determined during sales in Idaho, California, and Utah. Overall, 18,949 unique lots consisting of 23,479 animals were assessed during 125 dairy sales and 79 beef sales. Mean sale pr...

In this study, the incomplete gamma function, an exponential function, a mixed-log function and a polynomial function were evaluated to describe the lactation curve in Moroccan Holstein-Friesian dairy cows. Data from 1990 to 1999, comprising 77130 monthly milk yields of 6029 dairy cows in 280 dairy herds, were used. Edits were carried out by considering the lactation length (5 d and

The promotion of livestock production is widely believed to support enhanced diet quality and child nutrition, but the empirical evidence for this causal linkage remains narrow and ambiguous. This study examines whether adoption of improved dairy cow breeds is linked to farm-level outcomes that translate into household-level benefits including improved child nutrition outcomes in Uganda. Using ...

mastitis in cattle is a serious problem which causes considerable economic losses in the dairy cattle herds. the aim of this survey was to identify mycoflorain milk of healthy, clinical and subclinical mastitis of lactating holstein dairy cows. milk samples of 154 holstein dairy cows were collected from 10 dairy cattle herds in suburb of mashhad-iran. the treatment groups included 104 lactating...

Dairy cows have shown a steep increase in milk production, which is unfortunately characterized by a dramatic decline in reproductive performance. In these modern high yielding cows authors worldwide mention a higher number of puerperal problems, such as retained placenta, acute metritis and abnormal vaginal discharge. All of which are known to negatively influence reproductive capacity of thes...

The molecular mechanisms regulating the physiological adaptation of tissues important for nutrient partitioning and metabolism in lactating cows are still not completely understood. The aim of our study was to identify tissue-specific regulatory mechanisms necessary to accommodate metabolic changes associated with different genetic potential for milk performance. For this purpose, we analyzed m...

Calving records from April 1996 to December 2005 comprising 31863 calving events of 1173 dairy cows in a large commercial dairy herd were used to evaluate the effects of heat stress, using temperature-humidity index (THI) on milk yield and composition and reproductive performance of Holstein dairy cows under humid climatic conditions of Rasht in Iran. THI values were grouped into six groups: 30...