Physicochemical properties and chemical composition of muscle tissue of young pigs of large white breed and their correlation with some serum enzymes

The aim of the study was to investigate the biochemical parameters of blood serum, physicochemical properties and chemical composition of muscle tissue of young white pigs of English origin, as well as to calculate the level of correlations between the main quantitative traits. The experimental part of the work was carried out in LTd “AF” Dzerzhynets” Dnipropetrovsk region, Research Center for Biosafety and Environmental Control of Agricultural Resources Dnipro State Agrarian and Economic University, Ltd “Globinsky Meat Plant” Poltava region, laboratory of zootechnical analysis of the Institute of Pig Breeding and Agriculture and livestock laboratories of the Institute of Cereals NAAS. Blood sampling for biochemical studies was performed in 5-month-old animals, serum activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase and αamylase was determined. Physicochemical properties and chemical composition of the longest muscle of the back (m. Longissimus dorsi) were studied on the indicators of “moisture holding capacity, %”, “color intensity, units. ext. × 1000”, “tenderness”, c, “fat content, %”, “total moisture content, %”, “protein content, %”, “heat loss, %”, and “energy value of muscle tissue, kcal”. It was found that the biochemical parameters of blood serum of young pigs of large white breed at 5 months of age correspond to the physiological norm of clinically healthy animals. Thus, the activity of aspartate aminotransferase (AST) is 1.33 ± 0.074 mmol/h/l, alanine aminotransferase (ALT) – 1.87 ± 0.063 mmol/h/l, alkaline phosphatase – 291.99 ± 12.517 IU/l,α-amylase – 169.82 ± 5.005 g/h×l. Studies of physicochemical properties and chemical composition of samples of the longest back muscle of young pigs of large white breed show that the number of high quality samples in terms of “moisture holding capacity, %” is equal to 12.0%, “color intensity, units. ext. × 1000” – 16.0 %, “tenderness, c” – 12.0 % and “fat content, %” – 16.0 %. Significant correlations were established between the following pairs of features: moisture holding capacity, % × protein content, % (-0.484 ± 0.1825, tr = 2.65), moisture holding capacity, % × heat loss, % -0.416 ± 0.1896, tr = 2.19), fat content, % × moisture holding capacity, %, (-0.450 ± 01862, tr = 2.42), fat content, % × energy value, kcal (0.836 ± 0.1144, tr = 7.31), alanine aminotransferase (ALT) activity, mmol/h/l × pH, units of acidity, (0.443 ± 0.1859, tr = 2.37), alkaline phosphatase activity, units/l × color intensity, units. ext. × 1000 (-0.483 ± 0.1826, tr = 2.65), alkaline phosphatase activity, units/l × P, % (0.484 ± 0.1825, tr = 2.65).


Introduction
Intensification of the pig industry involves, along with improving the conditions of keeping and feeding the use of highly productive breeds, types and lines in the selection process, as well as the development and implementation of effective methods for assessing growth and development in early ontogeny, reproductive capacity of sows and breeding boars, fattening and meat qualities of their offspring (Kabanov, 2009;Allison & Laven, 2000;Aknevs'kyy et al., 2013;. An important issue is the study of interior features, data analysis and their use as markers of early prediction of signs of fattening, slaughter, meat qualities, as well as physicochemical and chemical properties of muscle tissue and sebum (Lugovoy et al., 2017;Tserenyuk, 2018;Martyshuk et al., 2019;Vuhliar, 2020;Novakovska, 2020;. The aim of the study was to investigate the biochemical parameters of blood serum, physicochemical properties and chemical composition of muscle tissue of young white pigs of English origin, as well as to calculate the level of correlations between the main quantitative traits. Citation: Khalak, V. I., & Gutyj, B. V. (2020). Physicochemical properties and chemical composition of muscle tissue of young pigs of large white breed and their correlation with some serum enzymes. Ukrainian Journal of Veterinary and Agricultural Sciences, 3(3), 34-38.

Materials and methods
The study was conducted in the conditions of breeding facilities for reproducting large white pigs at Ltd "AF Dzerzhynets" Dnipropetrovsk region, Research Center for Biosafety and Environmental Control of Agricultural Resources of the Dnipro State Agrarian and Economic University, Ltd "Globinsky Meat Plant" Poltava region, laboratory Institute of Pig Breeding and Agroindustrial Production of NAAS and Animal Husbandry Laboratory of the State Institution Institute of Grain Crops of NAAS. The work was performed according to the research program of NAAS № 30 "Pig breeding".
Control fattening of young pigs of this genotype was carried out in the farm in accordance with the requirements of modern research methods in pig breeding.
The energy value of muscle tissue was calculated by the chemical composition of the average sample of minced meat by the formula: Х = (С -(F+Z)) × 4.1+ F ×9.3 where: Х -caloric content 100 g of meat, cal; С -the amount of dry matter, g; F -amount of fat, g; Z -amount of ash, g.
A comprehensive assessment of meat quality was performed according to the method (Table 1) (Polyvoda, 1976). The strength of the correlations between traits was determined by the Cheddock scale (Table 2).

Table 2
Cheddock scale for grading the strength of the correlation between quantitative features The value of the correlation coefficient Correlation strength Noticeable 0.7-0.9 High 0.9-0.99 Very high Biometric processing of the obtained research results was performed according to the method (Lakin, 1990) using the programmable module "Data Analysis" in Microsoft Excel.
The coefficient of variation of the indicators characteriz-ing the physicochemical properties and chemical composition of the longest back muscle in the animals of the experimental group ranges from 2.49 (pH, acidity units) to 74.56 % (fat content, %). According to the scale of meat quality assessment according to physicochemical parameters (Polyvoda, 1976), the number of high quality samples according to the indicators "moisture holding capacity, %" is equal to 12.0 %, "color intensity, units. ext. × 1000" -16.0 %, "tenderness, c" -12.0 % and "fat content, %" -16.0 %.

Conclusions
1. According to the results of research it is established that the biochemical parameters of the serum of young pigs correspond to the physiological norm of clinically healthy animals of this species and age.
3. Effective biochemical markers for early prediction of high quality meat by active acidity (pH) and color intensity are the activity of alanine aminotransferase (ALT) and alkaline serum phosphatase of young pigs of large white breed of English origin at 5 months of age.
Prospects for further research. Further work in this area involves the study of fattening and meat qualities of young pigs of different intra-breed and inter-breed combinations, taking into account their genotype for some DNA markers.