Influence of maternal nutrient restriction and rumen-protected arginine supplementation on post-ruminal digestive enzyme activity of lamb offspring

ABSTRACT To determine the influence of maternal nutrient restriction and rumen-protected arginine supplementation on post-ruminal digestive enzyme activity in lambs, 31 multiparous, Rambouillet ewes were allocated to one of three dietary treatments at 54 d of gestation. Dietary treatments were 100% of nutrient requirements (control, CON; n = 11), 60% of control (restricted, RES; n = 10), or RES plus 180 mg rumen-protected arginine•kg BW-1•d-1 (RES-ARG; n = 10). Immediately after parturition, lambs were removed from dams and reared independently. Milk-replacer and alfalfa hay + creep feed were offered for ad libitum intake. At day 54 of age, lambs were slaughtered and the pancreas and small intestine were collected. Pancreatic (α-amylase and trypsin) and jejunal (maltase, glucoamylase, sucrase, isomaltase, and lactase) digestive enzyme activities were assayed. Data were analyzed using the GLM procedure of SAS for effects of treatment. Contrast statements were used to determine differences between means for effects of restriction (CON vs. RES and RES-ARG) and rumen-protected arginine supplementation (RES vs. RES-ARG). There was no influence (P ≥ 0.15) of maternal nutrient restriction or rumen-protected arginine supplementation on pancreatic or jejunal protein concentrations. No treatment effects were observed (P ≥ 0.12) for enzymes involved in starch digestion including pancreatic α-amylase and jejunal maltase, glucoamylase, and isomaltase. Sucrase activity was undetected in the jejunum of lambs across all treatments. Maternal nutrient restriction tended to increase (P = 0.08) pancreatic trypsin activity per gram protein in lambs. Lactase activity per gram protein in the jejunum of lambs tended to decrease (P = 0.09) with maternal nutrient restriction. Rumen-protected arginine supplementation to gestating ewes did not influence (P ≥ 0.19) digestive enzyme activities of lamb offspring. These data suggest that maternal nutrient restriction and rumen-protected arginine supplementation have minimal effects on digestive enzyme activity in offspring.