The Effect Of Extraneous GRF Gene Plasmid Injection On Growth And Development Of Calves

The objective of this paper were to explore effect of extraneous GRF gene plasmid injection on growth and development, bio-chemical index and hormone level in blood and of both GRF gene plasmid and SS vaccine injection together on growth performance and hormone level of calves.The results showed that the growth performance of every treatments injecting different dosage of GRF gene plasmid were better than control to some extend in whole trials.Average daily gain (ADG) of 3mg,6mg,9mg treatments were 14.29% (P>0.05) ,33.33% (PO.05), 26.19% (P<0.05) higher than control.And the feed/gain (F/G) were 10.69%,24.93%,21.37% lower than control.The body measures .including body length.height at withers.heart girth of every treatment had the tendency to increase. And the ratio of organ hadn't change significantly (P<0.05) .Injecting different dosage of GRF gene plasmid, the blood urea nitrogen (BUN) and triester glycerol (TG) level had the tendency to drop (P<0.05) and the glucose (GLU ) had the tendency to increase (P<0.01). The growth hormone (GH )levels in all treatments were higher than control. And the 6mg treatments reached the maximum.SS level had the smaller change in the 3mg and 6mg treatments.The somatostatin (SS) level of the 9mg treatment increased obviously (P<0.05).The change of bio-chemical indexes benefited to strengthen the anabolism for protein and catabolism for fat.The trial results showed growth performance through combination of both SS vaccine with different dosage of GRF gene plasmid injection were better than use of SS vaccine alone.The ADG of SS vaccine +3mg and SS vaccine +6mg treatments were 37.50%, 33.33% higher than SS vaccine treatment,respectively(P<0.05).And F/G were 25.56%, 23.47% lower, respectively.The GH level of all treatments increased significantly (P<0.05). The SS level of both SS vaccine and SS vaccine + 3mg treatments had the tendency to decline.But the SS vaccine +6mg treatment tended to increase.The whole trials results showed injection of GRF gene plasmid could improve growth performance of calves.