Effect of concentrate feeding type on methane production in sheep

The aim of the study is to investigate the effect of diets with different levels of concentrates on methane formation in sheep. The paper presents studies on Romanov sheep with rumen fistulas in the physiological yard of the Ernst All-Russian Institute of Animal Husbandry. The experiment was conducted using the period group method. In the first period, the sheep received a hay-concentrate diet containing 20 % concentrates, in the second - 30 % concentrates, in the third - 40 % concentrates by nutritional value. The animal diets were balanced in terms of nutritional and energy value, the level of minerals according to the standards. As a result, it was found that with the introduction of 20, 30 and 40 % concentrates in the sheep diet, the amount of released CH4 was 21.10; 17.88 and 15.88 l/day, respectively, i.e. an increase in the concentrate part of the diet by 2 times contributes to a decrease in CH4 production in the gastrointestinal tract by 1.33 times. The pH of the rumen with a diet containing 20 % (p ≤ 0.01), 30 and 40 % concentrates decreased 3 hours after feeding; before feeding, between the first and third periods, the pH level decreased from 6.71 to 6.25 (p ≤ 0.05); the amount of acid metabolites (VFA) increased from 6.65 to 7.21 mmol/100 ml before feeding and from 7.63 to 8.45 mmol/100 ml three hours after feeding; the amylolytic activity of the rumen after feeding gradually increased from 12.73 to 14.21 when changing the diet to a more concentrated one. With an increase in the level of concentrates, the amount of methanogens Methanobrevibacter smithii, Methanosphaera stadtmanae decreased both in the rumen and in the large intestine.