Milk fat yield affects the price received for milk by dairy farmers, and given the rising feed costs, maximizing diet digestibility is critical for the economical viability of dairy farms. Although feeding animal-vegetable fat or coconut oil to dairy cows can increase energy intake, they sometimes cause milk fat depression (MFD). Feeding monensin has been found to increase feed efficiency and m...

to study the effects of environmental factors on milk and fat yields (240day) traits of iranian buffaloes, 22596 and 22165 records were utilized for milk and fat yield traits, respectively. uni and bivariate analysis for estimation of (co)variation components of the traits were done in five lactations. milk yield in the 1st lactation had the highest number of records (4482), collected through c...

Calving records from the Animal Breeding Center of Iran collected from January 1993 to December 2007 and comprising 1 163 594 Holstein calving events from 2 552 herds were used to evaluate reported perinatal calf mortality, 305-d milk yield, 305-d fat yield of milk and 305-d fat percentage of milk in singleand twin-births. A logistic regression model was constructed to analyze calf mortality be...

in order to estimate the genetic parameters and comparison legendre polynomials for production traits of iranian holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. these records collected from 2006 to 2010, by the animal breeding center of iran. the genetic parameters were estimated usi...

The aim of this study was to estimate allelic and genotypic frequencies of five DNA markers that are positional and functional candidates for milk production traits in Czech Fleckvieh cattle. In addition, we evaluated the association of these markers with milk production traits and breeding values for milk production traits and also estimated linkage disequilibrium (LD) between two markers with...

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 raw milk quality has increasing importance for producer and consumer as it is directly related to processing, production and price. The aim of present study was to determine the relationship among intramammary infection (IMI) and raw milk parameters in Jersey crossbred cows. Total 24 lactating Jersey crossbred cows were randomly selected and representative animal wise morning milk samples w...

a total of 125 russian red pied cows were genotyped for the prolactim-related gene. the prl-rsai genotypes were analysed using the polymerase chain reaction -restriction fragment length polymorphism (pcr-rflp) method. in this breed, the frequencies of alleles were as follows;  a= 0.794 and b= 0.206. the frequencies of aa, ab and bb genotypes were 0.598, 0.392 and 0.01; respectively. results sho...

Conjugated linoleic acids (CLA) are octadecadienoic fatty acids that have profound effects on lipid metabolism. Our previous work showed that CLA (mixture of isomers) markedly reduced milk fat synthesis. In this study, our objective was to evaluate the effects of specific CLA isomers. Multiparous Holstein cows were used in a 3x3 Latin square design, and treatments were 4-day abomasal infusions ...