Scientific Journal of KubSAU

This review covers the advances of the molecular biology in the study of gene expression characteristics of animals in the amino acid imbalance

In this article, we discussed the problems of the metabolic disease of cows in peripartum period and profitability of the consequent lactation. The article has materials about adaptation in postpartum and arise ketosis, acidosis, laminit and reproductively reasons

The article presents a factorial model for determining the needs of lactating cows in essential amino acids. The algorithm of the model uses fragments from the NRC – 2001 models [39], CNCPS – 200 [60], and research materials published in the world literature. Instead of the transformation coefficients of the metabolizable lysine and methionine for milk production equal to 0.85 and 1.00, respectively, by the CNCPS, the coefficients 0.68 and 0.66 were used according to Doepel et al., 2004 [49] and the authors' own data [69]. Norms obtained using this model in lysine and methionine in milk production and maintenance in percentage of metabolizable protein (MP) were 7.28 and 2.4%, which is identical to the NRC – 2001 standards, equal to 7.2 and 2.4 % respectively, obtained by dose – response method based on dozens of experiments. The norm of histidine was 3.5%, which closely corresponds to the indicator of 2.4 and 2.7 % MP [74], obtained by the incremental addition method. This indicates that the presented model is distinguished by sufficiently high accuracy and is comparable with the models developed by the dose – response method. However, the determination of the need of cows for amino acids in this model is much less expensive than the dose – response method. The need for the absolute amount of metabolizable essential amino acids (MEAA) for milk production (35 kg/d, yield milk protein 1103 gytt6) and maintenance cow - 600 kg, g/d: lysine - 178, methionine - 59, arginine - 119, histidine - 60, isoleucine - 138, leucine - 248, phenylalanine - 152, threonine - 134, tryptophan - 38, valine - 174; the need for only milk production, g/d: 130; 42; 81; 42; 95; 175; 98; 74; 25; 112; the need for only maintenance, g/d: 50; 16; 38; 20; 43; 73; 54; 60; 14; 64; the need for 1 kg of milk (31.5 g of protein) g/kg: 3.7; 1.2; 2.3; 1.2; 2.7; 5.0; 2.8; 2.1; 0.7; 3.2; need to maintain, g / kg 0.75: 0.41; 0.14; 0.31; 0.16; 0.35; 0.60; 0.44; 0.50; 0.11; 0.53. In addition, the article presents the norms of amino acids per 1 kg of dry matter (DM) ration. However, the proposed standards need a comprehensive assessment in the research and practice of dairy farming. Research is needed to improve the models and predict the MEAA in the rations in the following areas: studying the metabolism of amino acids in the body of cows and determining their costs for maintaining the digestive tract, tissues and organs, refining, on this basis, the utilization of amino acids for milk protein production and maintenance; the development of ideal amino-acid profile of low-protein diets, both due to the adjustment of natural ingredients, and through the use of amino acid preparations that are protected from disintegration in the rumen