| Abstrakt: |
Correct nutrition with sufficient amount of optimal doses of microelements efficiently supports high levels of beef production and health of the animals throughout the feeding period. In the sphere of beef production, microelements are needed as additional supplements to play an important role in the productivity of cattle and the quality of the products made from them. Providing cattle with a more bioavailable source of deficient microelements could increase the metabolic process of the main nutrients, which would affect the intensity of bull growth and slaughter meat parameters. It has been revealed that organic complexes of deficient microelements have greater bioavailability. Throughout the experiment, Ukrainian Black Spotted bulls of 175–200 kg live weight were fed with diets enriched by chelate compounds of microelements with lysine and methionine. Animals of the second group were fed a diet with methionates of microelements in the following doses, mg/kg of live weight: iron – 0.05, cobalt – 0.04, iodine – 0.05 and selenium – 0.02; the third group received lysinates in the same doses of microelements; and the fourth group was given lysinates and methionates in a complex with half-doses of microelements. The studies were carried out using the following methods: zootechnical (productivity), biochemical (chemical blood composition), morphological (weight and sizes of certain tissues and internal organs), physical-chemical and sanitary meat parameters and statistical (mean arithmetic value and its error, significance level of difference between parameters). We found evidence and confirmed the benefits of using microelement supplemention with essential aminoacids in the bulls’ diet. Feeding chelate supplement to animals during the second feeding period improved hematological parameters, the productivity and nutrition value of beef. We determined that the best outcomes resulted from feeding bulls with lysinates and methionates in complex with microelements (Fe, Co, Se and I) during the second feeding period. The animals had 26.0% higher mean daily increments and 11.1% greater growth rates, and they grew 25.8% more intensively than the others that consumed only the main diet. The animals of this group had 5.2% higher slaughter yield and 4.8% higher carcass yield. The experimental groups were observed to have lower number of microorganisms in the longissimus layer in one field of view when analyzing impression smears. After 14 days of beef storage, qualitative reactions in the control group were positive with formaldehyde, sulphuric-acid copper, Nessler’s reagent and negative with benzidine. The reactions in the samples from experimental groups were doubtful. Less deterioration of beef stored at low positive temperatures (0…+2 ºС) was observed for the samples of experimental groups. [ABSTRACT FROM AUTHOR] |
