The impact of vitamin A restriction and ADH1C genotype on marbling in feedlot steers.
J Anim Sci
; 90(8): 2476-83, 2012 Aug.
Article
en En
| MEDLINE
| ID: mdl-22307477
ABSTRACT
A novel SNP was discovered within the promoter region of alcohol dehydrogenase 1C (ADH1C c.-64T>C), the C allele eliminating a potential binding site for the transcription factor C/EPBα. The purpose of this study was to examine if an interaction between this SNP and vitamin A restriction had an effect on carcass characteristics in beef cattle. Following backgrounding on a ß-carotene-deficient diet, 130 steers (50 TT, 50 CT, and 30 CC) were finished for 5 mo and received either no supplemental vitamin A (unsupplemented) or 750,000 IU/mo (supplemented). A subgroup of 5 steers ⢠genotype(-1) ⢠treatment(-1) was randomly selected for pre- and postfinishing liver biopsies to assess vitamin A status and measure gene expression. Unsupplemented steers (Bos taurus) had significantly greater (P < 0.05) marbling scores than supplemented steers. There was a significant interaction between genotype and vitamin A supplementation on ether-extractable intramuscular fat (IMF). Within the unsupplemented treatment, TT steers had nearly 23% greater IMF than CC steers. Additionally, unsupplemented TT steers had over 24% greater IMF than supplemented TT steers. Expression of ADH1C in the liver was additive with each additional T allele, potentially due to the elimination of a possible binding site for C/EBPα. It is plausible that CC cattle have reduced ability to metabolize retinol to retinaldehyde (and subsequently retinoic acid) and that a phenotypic effect is only observed when vitamin A is limiting. Therefore, ADH1C c.-64T>C genotype, in combination with reduced vitamin A supplementation, could potentially be implemented in marker-assisted management to maximize marbling in finishing cattle.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Vitamina A
/
Composición Corporal
/
Alcohol Deshidrogenasa
/
Bovinos
Límite:
Animals
Idioma:
En
Revista:
J Anim Sci
Año:
2012
Tipo del documento:
Article
País de afiliación:
Canadá