Although it has long been known that there are seasonal variations in the chemical characteristics of butterfat, it has as yet not been possible to assess the relative importance of nutritional and lactational influences. Moreover, in the Northern Hemisphere the problem is further complicated by the climatic effects, which necessitate the maintenance of cows indoors during the colder months, th...

The objectives of this study were to analyze the genetic properties of three measures of lactation persistency in Polish Holstein-Friesian cows, and possibly to choose one measure which could be used for estimation of breeding value for lactation persistency in the Polish dairy cattle population. Data included 117,327 first three lactations of 110,141 cows calved in 1995-2009. The lactation cur...

In order to determine the effect of folic acid on serum and milk folates in lactating sows as well as on serum folates and growth rate of the piglets, sows (n = 25) received either saline or 15 mg folic acid i.m. each week from d 2 after parturition to weaning, 26 d later. Blood samples were drawn from all sows at 110 d of gestation and every week during lactation. Milk samples were taken at d ...

Milk production of fall-calving dairy cows during subsequent summer grazing was evaluated in two consecutive years using a total of 80 mid- to late-lactation Holsteins. Cows calved during September and October and grazed from April to August in the following year. In yr 1, 27 cows grazed a native grass pasture and 13 cows grazed a native grass-clover mixed pasture containing 26% red clover and ...

According to precision livestock farming principles, it is essential apply feed intake forecasting processes real time feeding strategies in order improve the overall efficiency of chain. Considering lack a mechanistic model that predicts daily lactating sows, novel approach combining an online procedure with offline learning proposed. A database 39,090 lactations, from 6 different farms and co...

Variace / covariance components of 227118 first lactaiom test-day milk yield records belonged to 31258 Iranian Holstein cows were estimated using nine random regression models. Afterwards, different measures of persistency based on estimation breeding value were evaluated. Three functions were used to adjust fixed lactation curve: Ali and Schaeffer (AS), quadratic (LE3) and cubic (LE4) order of...