Submitted to: Biology of Reproduction Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: March 20, 2001
Publication Date: June 20, 2001
Citation: Ford, J.J., Wise, T.H., Lunstra, D.D., Rohrer, G.A. 2001. Interrelationships of porcine X and Y chromosomes with plasma gonadotropin concentrations [abstract]. Biology of Reproduction. 64 (Supplement 1):252. (Abstract #371) Technical Abstract: A quantitative trait locus (QTL) for plasma FSH exists on porcine X chromosome in Meishan (MS) by White composite (WC) boars. The objectives were to investigate effects of this X chromosome QTL, the Y chromosome and age at unilateral castration on gonadotropin secretion. Boars (n=132), controls or unilateral castration on d 1, 10, 56 or 112, were bled from birth to 220 d and assayed for follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T) and estrone (E). Plasma FSH, LH, T and E increased after birth followed by reductions and subsequent pubertal increases (p<0.01). Origin of Y chromosome had no effect on FSH, T or E. Sustained and maximal increases in FSH occurred earlier when unilateral castration was conducted on d 1 or d 10 than on d 56 or 112. The pubertal increase in FSH was greater (p<0.01) in boars with MS alleles for the X chromosome QTL than for boars with WC alleles. Similar to FSH, plasma LH increased during puberty; the increase was greater (p<0.05) in boars with MS alleles than in those with WC alleles for the X chromosome QTL (1.11 +/- 0.06 vs. 0.84 +/- 0.07 ng/ml). Similarly, boars with the MS Y chromosome had greater plasma LH concentrations than those with the WC Y chromosome (1.06 +/- 0.07 vs. 0.89 +/- 0.05 ng/ml, p<0.05). T and E were numerically greater (0.05<p<0.10) in boars with the MS X chromosome QTL. Breed of origin of the X chromosome QTL affected plasma FSH and LH, and origin of Y chromosome affected only LH, but to a lesser degree.