Gene. Pgrf On Pig Performance, Carcass Quality And Blood Biochemical Parameters,

S STUDY OF EFFECT OF PORCINE GROWTH HORMONE-RELEASING FACTOR GENE PLASMID ON GROWTH PERFORMANCE, CARCASS CHARACTERISTICS AND BLOOD PARAMETERS IN PIGS Gu Yu-hong (Animal Nutrition Institute, Si Chuan Agricultural University, Ya抋n, Si Chuan. 625014) ABSTRACT This study was undertaken to evaluate the effect of porcine growth hormone-releasing factor gene plasmid (pGRFGP) on growth performance in pigs, carcass quality and blood parameters. 30 two-line crossbred piglets weaned at 38-50 days of age. Pigs were allotted by weight, sex and genetic characteristics to fifteen groups(initial weight 10 ?0.5kg in per group). Allotted pigs were allotted to five treatments, there were 3 replicates in per treatment. Pigs in per treatment were treated with either saline, pGRFGP(0.25mg), pGRFGP(0.Smg), pGRFGP(lmg) or pGRFGP(2mg) by im injection in buttocks. 3 pigs in per treatment were slaughtered when pigs were approximately in 100kg BW. Blood samples were collected at slaughter. Data indicated that the growth response to pGRFGP was different in the different growing period. The growth performance improvement was more marked in 10-40kg BW than in 40-100kg BW in a dose-related manner. In comparision to control, feed efficiency was improved in the entire growing period, however, the improvement was mainly in 40-60kg BW. There was a trend for pGRFGP to reduced backfat thickness, increased loin eye area at the 13th rib and muscle mass. Treatments did not affect meat quality and heart, liver, spleen, kidne~y weights. Blood GH, GRF, IGF-I, BUN and glucose concentrations were not affected(P>0.05) by treatments.