ASSOCIATION OF DIACYLGLYCEROL ACYLTRANSFERASE 1 (DGAT1), STEAROYL-COA DESATURASE 1 (SCD1), AND STEROL REGULATORY ELEMENT BINDING PROTEIN 1 (SREBP-1) GENOTYPES WITH FAT CONTENT AND FATTY ACID COMPOSITION OF SOW COLOSTRUM AND TRANSIENT MILK

Abstract

Diacylglycerol acyltransferase 1 (DGAT1), stearoyl-CoA desaturase (SCD1), and sterol regulatory element binding protein 1 (SREBP-1) are key enzymes coded by lipogenic genes with important roles in lipid metabolism in the mammary glands of ruminant animals. This study analyzed the association of lipogenic gene markers with fat content and major fatty acids (i.e., palmitic acid C16:0, oleic acid C18:1n-9, and linoleic acid C18:2n-6) in sow colostrum and transient milk. Genotypes for DGAT1 (AA, AK, and KK), SCD1 (AA, AV, and VV), and SREBP-1 (LL, LS, and SS) were determined using DNA extracted from hair follicles of 17 Landrace (LDR), 15 Large White (LRW), and 15 F1 LDR×LRW and 9 R1 LRW×LDR crossbred sows through polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP). The AA and AK genotypes of the DGAT1 gene in F1 LDR×LRW and R1 LRW×LDR sows were associated (P<0.05) with higher fat content in colostrum than for the KK genotype. The AA and AV genotypes of the SCD1 gene in F1 LDR×LRW sows were associated (P<0.05) with higher C16:0 and C18:2n-6 in colostrum and transient milk than for the VV genotype. The LL genotype of the SREBP-1 gene was associated (P<0.05) with higher C18:2n-6 in colostrum from R1 LRW×LDR sows but lower C18:2 n-6 in colostrum from F1 LDR×LRW sows than for the LS genotype. The LS and SS genotypes of the SREBP-1 gene in Landrace sows were associated (P<0.05) with higher fat content but lower C18:1n-9 in transient milk than for the LL genotype. Some DGAT1, SCD1, and SREBP-1 genotypes can be used in a local marker-assisted selection program to effect changes in fat content and proportion of major fatty acids in sow colostrum and transient for some breeds.