title: Response to elemental sulfur by calves and sheep fed purified diets.
abstract: Free amino acid profiles in plasma and liver as well as body, organ and gastrointestinal growth were compared in 20 weanling bulls (four per treatment) fed diets deficient (.04%), excessive (.94 and 1.72%) or adequate (.34%) in S. Body, organ and gastrointestinal comparisons also were made with yearling rams fed .04 and .34% S diets. The .34% S diet was fed at two levels, one ad libitum, the other in amounts equal on a body weight.75 basis to that consumed by animals fed the .04% S diet ad libitum. Animals were allowed to consume other diets ad libitum. The calves fed the .04% S diet had negative S, but slightly positive N, balance and were unable to maintain body weight. As dietary S content was increased, plasma and liver methionine increased linearly. An increased histidine in plasma of calves fed the .04% S diet may be due to reduced intake because the calves restricted-fed the .34% S diet also had high plasma histidine. Plasma citrulline, cystine, serine and total nonessential amino acids decreased markedly as dietary S intake became adequate. Intermediate S diets resulted in reduced concentrations of plasma alanine, serine, proline and total nonessential amino acids. Calves restricted-fed the .34% S diet were the most efficient in retaining N with less urinary N. Excesses of S were not detrimental to growth, but plasma valine increased linearly as S intake increased. The S deficiency in calves reduced the ratio of the rumen-reticulum tissue to body weight, and in rams it reduced the ratio of gastrointestinal tissue and preintestinal tissue to body weight. Per kilogram of intestinal-free body weight, there was a linear decrease in liver and testes but an increase in adrenals as S was decreased for calves. The kidney, adrenals and pituitary were increased by S deficiency in rams. Of the amino acids assayed, only methionine from the plasma and liver in calves reflected both an excess and a deficiency of S independent of feed intake effects.
authors: Ruminant Nutr. Lab., U.S. Department of Agriculture, Beltsville, MD 20705.
authors: L L
authors: LL
authors: Slyter
authors: W
authors: W
authors: Chalupa
authors: R R
authors: RR
authors: Oltjen
mesh_terms: D000596:Amino Acids / Q000097:blood* / Q000378:metabolism; D000601:Amino Acids, Essential / Q000097:blood / Q000378:metabolism; D000818:Animals; D002417:Cattle / Q000378:metabolism*; D004032:Diet; D004064:Digestive System / Q000254:growth & development; D008099:Liver / Q000378:metabolism*; D008297:Male; D009584:Nitrogen / Q000378:metabolism*; D009929:Organ Size; D012756:Sheep / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000596:Amino Acids; D000601:Amino Acids, Essential; D013455:Sulfur; D009584:Nitrogen