Effect of nutrition and immunization against somatostatin on growth and insulin-like growth factors in sheep.
The effect of immunizing against somatostatin (SRIF), with SRIF conjugated to bovine thyroglobulin, was examined in cross-bred sheep fed either cut pasture or lucerne pellets. Plasma concentrations of GH were unaffected by SRIF immunization, but were lower in pellet-fed sheep. Plasma concentrations of insulin-like growth factor I (IGF-I) increased after immunization in sheep on both diets. Pasture-fed sheep had lower plasma concentrations of IGF-I than those on pellets. Sheep showed a small increase in growth rate in response to immunization. Immunization had no effect on carcass composition and did not affect plasma concentrations of IGF-II, free fatty acids or glucose. The results show that even though SRIF immunization increases plasma concentrations of IGF-I, it does not necessarily result in a large increase in growth rate.
D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001323:Autoantibodies / Q000032:analysis; D001835:Body Weight; D013006:Growth Hormone / Q000097:blood; D007114:Immunization; D009929:Organ Size; D012756:Sheep / Q000254:growth & development*; D013002:Somatomedins / Q000097:blood*; D013004:Somatostatin / Q000276:immunology*
D001323:Autoantibodies; D013002:Somatomedins; D013004:Somatostatin; D013006:Growth Hormone