PSXII-2 - Effect of TG5 (c.-422C>T) Polymorphism on Fatty Acid Composition of Muscle Tissue in Bull

Abstract: Intensive fat deposition is accompanied by an increased synthesis of saturated and monounsaturated fatty acids, resulting in a decrease in the proportion of polyunsaturated fatty acids in muscle tissue. The TG5 (c.-422C >T) polymorphism is associated with fat metabolism in Bos Taurus. The aim of the research was to study the effect of TG5 (c.-422C >T) polymorphism on fatty acid composition of muscle tissue in Hereford bulls. Polymorphism TG5 (c.-422C >T) was analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. The fatty acid composition of lipids was determined by gas-liquid chromatography on a “Kristall-4000 Lux” chromatograph (Russia). Hereford bulls were slaughtered at 15 months of age. Two groups of bulls with TG5^CC and TG5^CT genotypes were formed according to the results of genotyping. The total share of SFA and MUFA in muscles of bulls with the TG5^CC genotype was 71.2% and exceeded indicators of their peers by 1.0%. These data were consistent with increased synthesis of inter- and intramuscular fat, as well as subcutaneous adipose tissue. The TG5^CT genotype was associated with better fat quality in terms of essential fatty acids content, which accounted for 29.8%. Bulls with TG5^CT genotype outperformed their peers in content of palmitic by 0.74% and behenic by 0.02% among saturated fatty acids, palmitoleic by 0.67% among monounsaturated fatty acids, linoleic by 1.07%, linolenic by 0.15 % and arachidonic by 0.05% among polyunsaturated fatty acids. The maximum content of stearic (by 1.72%) and oleic (by 0.72%) fatty acids was observed in the group with the TG5^CC genotype. The greatest (by 0.08 units) ratio of unsaturated to saturated fatty acids indicated the best quality of adipose tissue in TG5^CT bulls. Thus, the increased intensity of fat deposition in TG5^CC carriers had a negative impact on the quality of meat.