UNC 636.082

I.B. Bankovska, candidate of agricultural sciences, a senior researcher
V.M. Voloshchuk, doctor of agricultural sciences, professor
Institute of Pig Breeding and agroindustrial production of NAAS

The purpose of this study was to analyze the level of impact factors of genotype and type of the floor on the morphological composition and the ratio of tissues in pigs’ carcasses. Studies were conducted on fattening livestock of the Large White breed (LW) of two breeds combination of sows of the Large White breed with boars of Landrace breed (LW x L) and breed-linear combination of two breeds gilts of the Large White and Landrace with terminal boars of specialized meat line “OptiMus” (LW x L)xSS. In the control group young pigs of each genotype were fattened on the solid concrete floor for 20 heads. In the experimental group young pigs were housed together 60 heads in the section of premise that was adapted for using the deep constant organic sand and straw litter. During fattening (from the end of August to mid-November) animals received balanced combined feed-stuffs. Pigs from each technological group at live weight of 100kg (respectively 10 heads of each genotype) were transferred to the slaughter house for the evaluation of a meaty of carcasses by the method of fallouts. The analysis of results shows that animals received with using boars of specialized line “OptiMus”( р≤ 0.001), reacted negatively to the concrete floor by reducing weight of carcasses and better showed its potential of the meat productivity under conditions of energy retentive technology η²=37.2%, р≤0.01. Factors of floor type and genotype influenced on muscle weight with moderate force , according η²=12.1% (р≤0.01) and η²=13.7% (р≤0.01). Pigs of each genotype both technological groups had no difference with the percentage of meat output in carcasses. It was found out that the effect of floor type and genotype on fat weight in carcasses of pigs was higher than on meat weight and relatively was η²=26.2% (р≤0.001) and η²=23.1 (р≤0.001). An important interaction of both factors was at 61% (р≤0.01), that each genotype had its own specificity of the fat deposition accordance with the technological peculiarities of fattening process. The impact force of the floor type on fat weight of purebred was 21.6% (р≤0.05), two breeds combination -15.9% (р≤0.08), breed-linear hybrid – 69.2% (р≤0.001). Gilts combination (LW x L) stable responded to technological peculiarities of different conditions. The effect of factor of genotype had a significant influence on the fatty of pigs’ carcasses at η²=34.1 – 45.9% (р≤0.001) for both technological groups. It was found out the significant advantage of bones’ weight in pigs of each genotype which were on concrete than on deep constant litter. Thus, the influence force of genetic factor on bones’ weight was slightly higher η²=36.4% (р≤0.0001) compared with the effect of floor type η²=28.2% (р≤0.0001). Thus, in alternative growing conditions of pigs of different genotypes there are specific peculiarities of the formation of qualitative characteristics and the relative distribution of morphological components of carcasses that must be considered in optimization of pork production. In pigs which were housed on deep litter compared with analogs on the concrete floor at higher level of the absolute meat and fat content in carcasses it was observed more intensive accumulation of adipose tissue which reduces relative indexes of their meat productivity.

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