Animal and Tissue Collections
Twelve mature 1/2 MS X 1/2 WC crossbred boars were selected from the U.S. Meat Animal Research Center swine population based upon their divergent plasma FSH concentrations, determined as the mean of three blood samples per boar, obtained by venipuncture when they were 4, 5, and 6 mo of age. Relative differences in FSH are maximal at this period of pubertal development. These boars (6 with low and 6 with high plasma FSH concentrations) were progeny from 1/4 MS X 3/4 WC boars mated to 3/4 MS X 1/4 WC females or the reciprocal combination. Anterior pituitaries were obtained at slaughter at 14 mo of age, dissected into two halves, and frozen separately in liquid nitrogen immediately after removal from the animal. canadian neighbor pharmacy
FSH concentrations were determined by RIA in plasma samples obtained by jugular venipuncture at 4-6 mo of age and at 14 mo of age, the day prior to the day animals were killed, and in extracts of half of each anterior pituitary gland. Antisera against ovine FSH (AFP-C5288113), ovine FSH for iodination (NIADDK-oFSH-17, AFP-6446C), and porcine FSH reference preparation (USDA B-1) were provided by the USDA/NIH National Hormone and Pituitary Program (Rockville, MD). The interassay coefficient of variation for pools of sera from intact or castrated males were 14.0% and 13.0% with mean concentrations of 296 and 1293 ng/ml, respectively.