Rumen cannulation of young cattle depending on protein diet

Abstract

An experiment has been carried to determine the degradable and non-degradable protein content in grass and concentrated feed and its influence on operated sire rumen cannulation of black-and-white breed (with body weight of 120–160 kg). The grass chemical composition and concentrated feed research shows that there is a wide range of crude protein content and its degradable and non-degradable fractions. The level of crude protein in concentrated feed varies from 96 g (barley grain) to 380–383 g (extruded lupine grain and rapeseed meal). The amount of degradable protein is 81 (barley grain), 303 g (rapeseed meal). Degradability of crude protein ranges from 57 % (extruded rapeseed) to 84–86 % (barley and wheat grain). The crude protein content in the presented samples of grass feed is 27 (corn silage) – 93 g (cereal hay), degradable protein – from 17–19 (cereal hay and corn silage), up to 38 g (mixed grass), non-degradable – 8 (corn silage, 76 g (cereal hay). The degradable and non-degradable protein ration was 2:7. The crude protein increase in summer and winter calve diet up to 70 % contributes a lower accumulation of ammonia in the rumen fluid (by 19.6–20.6 % ) and activation of VFA synthesis (by 16.5–18.2). It also contributes the increase of the ciliate number (by15,7–15,9), total and protein nitrogen (by 7.2–7.4 and 8.0–12.3 %). Feeding on protein degradability (of 65–60 %) lets the rumen metabolism processes slow down, reduce the microbiota enzyme activity, the protein nitrogen proportion and the ammonia level increasing. According to the analysis results of economic diet indices with different protein fractional composition it has been determined that the ration use with protein degradability of 70 %, and metabolizable energy costs – by 4.0–5.0 % are economically reasonable in summer and winter periods. Key words: concentrated feeds, grain, degradable protein, non-degradable protein, calves.