Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/1997
Publication Date: N/A
Technical Abstract: Young intact male swine (total n = 54) were used to study the effect of recombinant GH treatment (daily im injections of 200 ug/kg) for 2 wk on body weight gain and bone development. Pigs were allotted to one of three age groups (1, 4 or 9 wk of age) and one of two treatments (GH or vehicle injections for 2 wk) by litter and weight shortly after birth. There were 8 treated and 8 control animals/age group. At the end of GH treatment pig were sacrificed, blood samples were collected, and the right tibia removed for evaluation. The 1 wk age group remained with their dam and littermates. The 4 and 9 wk age groups were weaned at 3 wk of age and fed typical nursery and early grower diets. Mean starting and ending body weights (kg) for the 1, 4 and 9 wk age groups were 2.53 and 5.45, 7.05 and 15.46, and 27.12 and 39.84, respectively. GH treatment did not increase (P > .2 to .9) ADG for any age group, and did not increase (P > .5 to .7) gain:feed ratio for the 4 and 9 wk age groups. The effect of GH treatment on ADFI was inconsistent. GH treatment did not affect (P > .4 to .9) tibia fresh weight, length, midpoint width (narrow and wide measurements), breaking force (kg), breaking force in g/mm**2, or bone mineral content estimated by dual energy X-ray absorption. However, serum IGF-1 concentrations were increased (P < .01) by GH treatment. In conclusion, body weight gain, tibia measurements and tibia breaking strength in young male swine ranging from 3 to 11 wk of age (2.5 to 40 kg) were not responsive to a GH treatment administered daily for 2 wk.