Evaluation of rations of high-yielding cows with different energy levels

The materials of the publication reflect results scientific research conducted on Simmental breed dairy cows in conditions “Pchany-Denkovych” farm Stryi district Lviv region. study is based optimizing normalized energy nutrition with a milk yield 6000 kg or more per lactation. main objective was to impact different levels by lactation phase and its effect productivity, hematological indicators, level individual rumen metabolites, digestibility essential nutrients, nitrogen balance, live weight dynamics. Three groups eight each were selected for research. rations experimental animals provided inclusion protein-fat concentrate compound feed at rate 5–10 % nutrition. ration consisted bulk fodder, cereal-bean hay, silage, balanced feed, which fed from table form mixture prepared mixer–the practices year-round uniform feeding walking yard. deficiency mineral substances diet replenished due iodized salt, monocalcium phosphate, polysalts trace elements. Feeding housing all during comparison period lasting 15 days same differed reference terms nutrient availability percentages. analysis obtained showed that increasing supply had positive productivity. In first lactation, highest third group, indicates are approaching maximum possible potential This trend persists both second periods. increased use increase cows. During indicators content, probable number amylo- cellulolytic bacteria revealed - quantitative advantage (second group) compared control 1.52–2.33 1.67–2.54 million/ml. A similar pattern observed proteolytic bacteria, contributed enzymatic activity microflora. Regarding primary nutrients their growing established groups, confirms experiment. Thus, group characterized assimilation nitrogen. Its balance (+7.1) (+3.0) first, negative. these highest: consumed – 31.7 digested 48.5 %. studies provide reason recommend 5% diet's total will ensure an productivity make it optimize calving mid-lactation.