Changes in the parameters of ruminal digesta in vitro when using sunflower husk and zinc in ultrafine form

Abstract

Relevance. By-products of agricultural processing are considered as raw materials for use in animal feed formulations in order to reduce the cost of animal feeding. The inclusion of mineral supplements can increase the nutritional value of diets and allow the use of lower quality feeds.Methods. The object of the study is ruminal digesta from bull-calves with chronic scar fistula, weighing 240–245 kg, 11–12 months old; ultrafine particles (UFP) of zinc (Zn — size 110 nm, Zn 90%). Metabolom was studied on the basis of tests of the following feed samples: sunflower husk subjected to mechanical grinding without treatment and with treatment (hydromodule (water), ultrasonication at 20°С, 15 minutes, 27 kHz). The level of methane was determined on the “Crystallux-2000M” by gas chromatography, the level of volatile fatty acids (VFA) in the contents of the rumen — by gas chromatography on the gas chromatograph “Crystallux-4000M”, determination of nitrogen forms— according to GOST 26180-84.Results. The inclusion of UHF zinc at a dosage of 3.0 mg and 6.0 mg improved the digestibility of DM relative to the control sample by 21.9–22.4% (р ≤ 0.05). The additional inclusion of zinc at a dosage of 1.5 mg and 3 mg contributed to an increase in acetate by 94.7% and 97.9%, propionate —by 85.4% and 71.4% (р ≤ 0.05), butyrate— by 95.6% and 87.3% respectively relative to the control sample. The presence of zinc at a dosage of 6.0 mg significantly increased the concentration of acetate, propionate, butyrate and caproic acid —by 94.9%, 93.2%, 94.4% and 75.4% (р ≤ 0.05) relative to the control. The level of methane formation in all experimental groups relative to the control was significantly lower.