Comparison of growth performance and zinc absorption, retention, and excretion in weanling pigs fed diets supplemented with zinc-polysaccharide or zinc oxide1

Abstract

Fifty weanling crossbred pigs averaging 6.2 kg of initial BW and 21 d of age were used in a 5-wk experiment to evaluate lower dietary concentrations of an organic source of Zn as a Zn-polysaccharide (Zn-PS) compared with 2,000 ppm of inorganic Zn as ZnO, with growth performance, plasma concentrations of Zn and Cu, and Zn and Cu balance as the criteria. The pigs were fed individually in metabolism crates, and Zn and Cu balance were measured on individual pigs (10 replications per treatment) from d 22 to 26. The basal Phase 1 (d 0 to 14) and Phase 2 (d 14 to 35) diets contained 125 or 100 ppm added Zn as Zn sulfate, respectively, and met all nutrient requirements. Treatments were the basal Phase 1 and 2 diets supplemented with 0, 150, 300, or 450 ppm of Zn as Zn-PS or 2,000 ppm Zn as ZnO. Blood samples were collected from all pigs on d 7, 14, and 28. For pigs fed increasing Zn as Zn-PS, there were no linear or quadratic responses (P > or = 0.16) in ADG, ADFI, or G:F for Phases 1 or 2 or overall. For single degree of freedom treatment comparisons, Phase 1 ADG and G:F were greater (P < or = 0.05) for pigs fed 2,000 ppm Zn as ZnO than for pigs fed the control diet or the diet containing 150 ppm Zn as Zn-PS. For Phase 2 and overall, ADG and G:F for pigs fed the diets containing 300 or 450 ppm of Zn as Zn-PS did not differ (P > or = 0.29) from pigs fed the diet containing ZnO. Pigs fed the diet containing ZnO also had a greater Phase 2 (P < or = 0.10) and overall (P < or = 0.05) ADG and G:F than pigs fed the control diet. There were no differences (P > or = 0.46) in ADFI for any planned comparison. There were linear increases (P < 0.001) in the Zn excreted (mg/d) with increasing dietary Zn-PS. Pigs fed the diet containing ZnO absorbed, retained, and excreted more Zn (P < 0.001) than pigs fed the control diet or any of the diets containing Zn-PS. In conclusion, Phase 2 and overall growth performance by pigs fed diets containing 300 or 450 ppm Zn as Zn-PS did not differ from that of pigs fed 2,000 ppm Zn as ZnO; however, feeding 300 ppm Zn as Zn-PS decreased Zn excretion by 76% compared with feeding 2,000 ppm Zn as ZnO.

Evaluation of the effects of pharmacological zinc oxide and phosphorus source on weaned piglet growth performance, plasma minerals and mineral digestibility

“…However, in other studies, pharmacological Zn from ZnO had no effect on plasma Cu concentration (Buff et al, 2005;Shelton et al, 2011) or actually increased plasma Cu concentration, except when both Zn and Cu were combined in the diet (Shelton et al, 2011). Differences in the results between the present trial and the previously reported trials may be associated with the level of Cu or Zn fed or the source of Cu supplied in the diets.…”

“…This is in contrast with the apparent faecal Zn digestibility of the present trial, which was negative and increased as ZnO supplementation increased to 3500 mg/kg. However, Buff et al (2005) reported a 53% increase in Zn absorption and a 60% increase in Zn retention when pigs were fed 2000 mg/kg Zn from ZnO compared with a basal diet containing 162 mg/kg Zn. The discrepancies in the data may be due to collection methods, the time and age of the pigs at sampling, ADFIand thus average daily Zn intake -and the bioavailability of the source of Zn used.…”

Dietary Zinc Glycine Chelate on Growth Performance, Tissue Mineral Concentrations, and Serum Enzyme Activity in Weanling Piglets

“…Ward et al [17] also reported that 250 mg/kg of Zn as Zn-methionine increased growth performance of weanling pigs equal to that of 2,000 mg/kg of Zn as ZnO. Moreover, supplementation of weanling pig diets with 300 or 450 mg/kg of Zn as Zn-PS maintained phase 2 (d 14 to 35) and overall growth performance similar to that obtained with 2,000 mg/kg of Zn as ZnO [18]. Our previous study showed supplementation with appropriate zinc glycine chelate (Zn-Gly) can improve the growth performance and immunological capacity of broilers [16].…”

Effect of dietary organic zinc sources on growth performance, incidence of diarrhoea, serum and tissue zinc concentrations, and intestinal morphology in growing rabbits

“…It was demonstrated that feeding weaning pigs a diet containing 250 mg/kg Zn as ZnMet increased growth performance in a similar way to pigs fed a diet containing 2000 mg/kg Zn as ZnO (Ward et al, 1996). Moreover, it was shown that growth performance of pigs fed a diet containing 300 or 500 mg/kg Zn as Zn-Polysaccharide (Zn-PS) did not differ from that of pigs fed 2000 mg/kg Zn as ZnO; however, feeding 300 mg/kg Zn as Zn-PS decreased Zn excretion by 76% compared with feeding 2000 mg/kg Zn as ZnO (Buff et al, 2005). In addition, the adverse effect of high Zn intake on copper availability has to be considered (Maret and Sandstead, 2006).…”