Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 17, 1996
Publication Date: N/A
Interpretive Summary: Meishan pigs have larger litters than other breeds of pigs in the U.S. We determined previously that Meishan boars have high concentrations of follicle stimulating hormone in their blood; thus, the present study investigated what other factors in the pituitary gland differ between Meishan and White composite boars. Using differential display PCR, a relatively new technique, we found that messenger ribonucleic acid for thyroid stimulating hormone beta was greater in Meishan boars. This difference was confirmed in both males and females as was greater amounts of thyroid stimulating hormone in the blood of Meishans. These findings will aid in the design of subsequent studies into understanding why Meishan pigs are more prolific than other breeds of swine.
Technical Abstract: Anterior pituitary gland RNA isolated from Meishan and White Composite boars was compared by a newly developed method of differential expression cloning called differential display. Thyroid-stimulating hormone beta (TSH-beta) subunit gene was found to be more highly expressed in Meishan than in White Composite pigs. Subsequently, RNase protection assay and pTSH RIA confirmed the results observed from the differential display experiment and showed that expression of TSH-beta and plasma TSH concentration were significantly greater in Meishan than in White Composites. Elevated plasma TSH concentration may contribute to Meishan pigs reaching sexual maturity earlier than White Composites or other European breeds. This method provides a useful molecular tool to detect differentially expressed genes between individuals, populations or breeds, and to identify candidate genes that control economically important quantitative traits in livestock.