Change of plasma insulin-like growth factor-1 (IGF-1) concentration with early growth in Japanese beef cattle
The aim of the present study was to examine the change in plasma insulin-like growth factor-1 (IGF-1) concentration with early growth, changes of bodyweight (BW) and relative dairy gain (RDG) in the pre- (PRW) and postweaning periods (POW) in Japanese beef cattle, and relationships with metabolites. A total of 33 calves, 22 Japanese black, 6 Japanese shorthorn and 5 of their crossbreed were studied. Insulin-like growth factor-1 and metabolite (glucose, triacylglycerol, nonesterified fatty acid) levels in the plasma, from jugular vein blood taken every month, were measured along with BW. Insulin-like growth factor-1 in POW increased dramatically with increase of BW (P < 0.05), and the correlation was positive at 0.52 (P < 0.01). Glucose levels correlated significantly with BW, RDG and IGF-1 (P < 0.01). Metabolic required calorie correlated positively with IGF-1 (P < 0.01). Also, correlations of BW in POW, with BW and RDG in PRW were positive (P < 0.01). Growth in PRW would be influenced by maternal effects, while active self-secretion of IGF-1 in POW might contribute to POW growth. These factors suggested that to increase growth in PRW, maintaining enough maternal effect and IGF-1 level in POW, was important for establishing better growth after weaning.
Document Type: Research Article
Affiliations: 1: Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo and 2: Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai-shi, Japan
Publication date: June 1, 2003