title: Effects of the interrelationship between zinc oxide and copper sulfate on growth performance of early-weaned pigs.
abstract: We conducted four experiments to examine the effects of adding zinc oxide (ZnO) and(or) copper sulfate (CuSO4) to diets for weanling pigs. In Exp. 1 and 2, weanling pigs (initially 5.3 kg and 19 +/- 2 d of age) were fed diets containing 250 ppm of added Cu (CuSO4) and either 110 or 3,110 ppm of added. Zn (ZnO). No differences (P > .10) were observed in either experiment for ADG, ADFI, or feed efficiency (G:F). In Exp. 3,240 pigs (initially 4.45 kg and 15 +/- 2 d of age) were used to determine the interactive effects of added dietary ZnO and(or) CuSO4. Dietary treatments were in a 2 x 2 factorial arrangement; Zn (165 or 3,000 ppm) and Cu (16.5 or 250 ppm) were the main effects. Pigs were fed a high nutrient dense diet from d 0 to 14 after weaning and a less complex diet from d 14 to 28 after weaning, both containing the same mineral fortifications. From d 0 to 14, pigs fed 3,000 ppm Zn, with or without 250 ppm Cu, had improved ADG (P < .01) compared with pigs fed the control (16.5 ppm Cu and 165 ppm Zn) or diets with only added Cu. From d 14 to 28, pigs fed the diet containing 3,000 ppm added Zn, without 250 ppm Cu, had greater ADG than pigs fed the other diets (Zn x Cu interaction, P < .01). In Exp. 4, 264 pigs (initially 4.17 kg and 12 +/- 3 d of age) were fed a high nutrient dense diet supplemented with 3,000 ppm of Zn (ZnO) from d 0 to 14 after weaning. On d 14, pigs were switched to the diets containing experimental mineral levels identical to those of Exp. 3. From d 14 to 28 after weaning, added Zn improved ADG but not when the diet contained 250 ppm Cu (Zn x Cu interaction, P < .05). Feeding 3,000 ppm of Zn from ZnO is a viable means of improving nursery pig performance, but additive responses to growth-promotant levels of CuSO4 (250 ppm Cu) were not observed.
authors.affiliation: Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506-0201, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Smith
authors.forename: M D
authors.initials: MD
authors.lastname: Tokach
authors.forename: R D
authors.initials: RD
authors.lastname: Goodband
authors.forename: J L
authors.initials: JL
authors.lastname: Nelssen
authors.forename: B T
authors.initials: BT
authors.lastname: Richert
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D019327:Copper Sulfate / Q000008:administration & dosage / Q000494:pharmacology*; D004032:Diet / Q000662:veterinary; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004357:Drug Synergism; D005260:Female; D008297:Male; D011897:Random Allocation; D013552:Swine / Q000254:growth & development* / Q000502:physiology; D013997:Time Factors; D014886:Weaning; D015430:Weight Gain / Q000187:drug effects / Q000502:physiology; D015034:Zinc Oxide / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D019327:Copper Sulfate; D015034:Zinc Oxide