Relationship of porcine plasma free insulin-like growth factor 1 (IGF-1) with the growth performance and scrotal length of landrace boars.

Insulin-like Growth Factor 1 (IGF-I) is a 7.6 kDa, 70 amino acid residue peptide hormone that has been shown to be involved in the metabolic regulation of growth and reproduction in livestock. The present study was undertaken to quantify the concentrations of plasma free IGF-I in growing Landrace boars and determine whether the plasma free IGF-I concentration can be used as a selection criterion for growth. A total of fourteen (n = 14) Landrace boars were bled, weighed and monitored for ADG, backfat thickness and scrotal length at 15 and 24 weeks of age. Plasma samples were extracted from the blood and plasma free IGF-I concentrations were measured using the DSL 10-9400 Active free IGF-I Enzyme-Linked Immunosorbent (ELISA) kit. Experimental Landrace boars data on live weight, ADG, backfat thickness and scrotal length were correlated with their levels of plasma free IGF-I.