Pituitary Porcine Growth Hormone (pGH) and a Recombinant pGH Analog Stimulate Pig Growth Performance in a Similar Manner

Abstract

This study was conducted to establish the extent to which different doses of pituitary porcine growth hormone (ppGH) increase pig growth performance. Pigs were treated daily for 11 wk with 0, 35 or 70 micrograms ppGH/kg BW. In addition, these effects were compared with those produced by treating pigs with 0, 35, 70 or 140 micrograms.kg BW-1.d-1 of a recombinantly derived analog of porcine growth hormone (rpGH). This analog lacks the first seven amino acids at the NH2 terminus. Growth rate was increased similarly by ppGH and rpGH (the maximal increase was 19%). Feed efficiency was improved by ppGH and rpGH (the maximal response was 25%). This improvement in feed efficiency was associated with a decrease in feed intake (17% with the largest dose of rpGH). Both ppGH and rpGH decreased adipose tissue growth and increased muscle mass. Carcass lipid was decreased by 68% in pigs treated with the largest dose of rpGH. The recombinant pGH analog appeared to be less potent than ppGH in decreasing adipose tissue growth rate. All other parameters measured, however, indicated that rpGH mimicked the biological effects of ppGH (including binding to pig liver membranes and induction of insulin-like growth factor I production). Sensory panel evaluations indicated that neither ppGH nor rpGH affected pork palatability. Larger doses of pGH (greater than 70 micrograms/kg BW) adversely affected pig mobility. This impairment in mobility appears to be due to osteochondrosis. Our findings establish that the rpGH analog is equipotent to ppGH in stimulating growth performance and that pigs can be treated without any significant adverse effects when they are treated with less than 70 micrograms of pGH.kg BW-1.d-1.

Differentiation of the effects of somatotropin and enhanced growth rate on the occurrence of osteochondrosis in pigs

“…Can iilS; ptnerton et al 1986). An increased incidence of OC has also been shown in pigs injected with recombinant porcine somatotropin (rpST) (Machlin 1972;Evock et al 1988 Before analysis, the bones were thawed at room temperature.…”

Effects of exogenous porcine somatotropin on performance, testicular steroid production and fat levels of boar-taint-related compounds in young boars

“…Altematively, lower androstenone levels in the fat muld be the result of an accelerated clearance of circulating androstenone, in keeping with the pST-induced augmentation of liver and kidney weights (Evock et al 1988;Bonneau et al 1989;Bryan et al 1989). Indeed, fat androstenone concentration has been shown to be dependent on both the level oftesticular androstenone synthesis and the intensity of androstenone clearance from the blood (Bonneau et al 1982).…”

Effects of prolonged release recombinant porcine somatotropin and dietary protein on the growth, feed efficiency, carcass yield and meat quality of pigs

“…content 10% on average and reduces carcass fatby 10-20% in finishing pigs (Bechtel et al 1988;Etherton 1988;Evock et al 1988;Boyd and Bauman 1989;Campbell et al 1989Campbell et al a, 1990Chung et al 1989;Hanrahan 1990; Stahly, 1990;Evans et al l99l' McNamara et al 1991). Such improvements in the production efficiency of lean meat are certainly consistent with current consumer demands @ood 1987) and with the industries' desire to improve carcass srade index (Evans et al 1991).…”

“…Evock et al (1988) and Buonomo and Baile (1991) considered that nurrition is one of the primary factors likely to affect or limit the anabolic effects of growth hormone. Treating pigs with pST was reported to cause an increase in protein synthesis and deposition rates by tp to 20% (Hart and Johnson 1986) as well as increased nitrogen retention (Wray-Cahen et al 1991).…”