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 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 objective of this study was to investigate the effect of milking frequency (two times daily vs. three times daily) on the 305-d lactation milk, fat and protein yield and fat and protein percentage of Holstein dairy cows in Morocco. Data analyzed were 31400 records collected between 2009 and 2016 on 14272 cows raised in 194 herds. The frequency of milking had significant effects (P<...

assessing the effects of monensin on economic factors of milk (percents of protein and fat), and quality of milk fat during early lactation. thirteen multiparous holstein cows were blocked into a control and a treatment group from 3 weeks prepartum to 45 days postpartum according the number of their calving. the groups received similar diets. the treatment group received monensin added to grain...

the aim of this study was to estimate genetic parameters of age at first calving and its relationship with productive traits of holstein dairy cows. a total of 24491 first lactation records (2x 305d) which were collected from 1995 to 2009 were used. the general linear model (glm) procedure was applied to determine effective factors on studied traits. herd-year-season (hys) and age at first calv...

in this research, in order to describe milk production traits lactation mahabadi goat breed, seven statistical functions were fitted using 1665 milk production traits records and 833 body weight records. the milk production traits were milk yield, fat percent, fat yield, protein percent, protein yield, lactose percent and snf percent. these records have been recorded on 123 goats during years o...

background: methionine has been suggested as the firstlimitingamino acid for milk production in ruminants. it is importanthow to increase milk protein yield and milk fat in dairy ruminants.objectives: this study was set to investigate the effect of rumenprotected methionine (rpmet) on milk composition of lactatingcashmere rayeni goats. methods: 40 healthy singletoncashmere rayeni goats about 3 ...

abstract             (co) variance components of milk, fat and protein yield of 11368 first lactation iranian holstein dairy cow were estimated by single trait random regression test-day models and restricted maximum likelihood (reml) method. in this study the homogeneous residual variance was assumed throughout lactation. estimated heritability for 305-day production traits ranged from 0.25 to...