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ZINC AMINO ACID COMPLEXES AND PICOLINIC ACID: EFFECTS ON SWINE, RATS AND POULTRY (EVERTED GUT, INTESTINAL PERFUSION, METHIONINE)
Abstract
Three hundred fifty rats were used in three experiments to (1) validate the in vitro everted gut procedure, (2) determine the effect of increasing ratios of picolinic acid (PA) on ('65)Zn uptake and (3) determine the effect of PA on uptake of ('65)Zn from ('65)ZnCl(,2), ('65)Zn-methionine (ZnMet) and ('65)Zn-lysine (ZnLys) at pH 6, 7 and 8. ('65)ZnCl(,2) uptake decreased as time from sacrifice to start of incubation increased but labeled amino acid uptake was not affected. The addition of PA decreased Zn uptake from ('65)ZnCL(,2) linearly as the PA molar ratio was increased from 0 to 2.5 using a constant Zn level. In the third rat experiment the addition of 5 M PA to constant Zn levels from the three Zn sources depressed ('65)Zn uptake regardless of Zn source. Zinc uptake was affected by pH and was usually greatest at pH 7 from all Zn sources. Amino acid uptake tended to be greater at the lower pHs. The addition of PA to nursery pig diets did not improve performance or Zn status of the 90 pigs used in a 28-d study. Also PA did not improve Zn balance in young mature rats. Two additional experiments were conducted utilizing an in vitro continuous flow non-everted gut system with 20 pigs and 14 broiler chickens, using ('65)ZnCl(,2) and ('65)ZnMet with or without picolinic acid added at 5 M ratio to Zn. Total Zn absorption between the two Zn sources was essentially identical in the pig gut segments and was not significantly different in the poultry gut segments. The addition of 5 M PA depressed uptake from both Zn sources. The data suggest that the Zn sources used are of similar biological value and do not support the hypothesis that PA facilitates or enhances Zn absorption.
Subject Area
Livestock
Recommended Citation
HILL, DALE A, "ZINC AMINO ACID COMPLEXES AND PICOLINIC ACID: EFFECTS ON SWINE, RATS AND POULTRY (EVERTED GUT, INTESTINAL PERFUSION, METHIONINE)" (1986). ETD collection for University of Nebraska-Lincoln. AAI8704551.
https://digitalcommons.unl.edu/dissertations/AAI8704551