Bioavailability of two sources of zinc in weanling pigs

Abstract

-Thirty-two pigs, weaned at 28 days of age with an average body weight of 9 kg, were used in an experiment devoted to the assessment of the bioavailability of an organic Zn source (ZnOrg) compared to Zn sulfate. Pigs were fed a basal diet containing 28 mg·kg -1 of Zn supplemented with ZnSO 4 or ZnOrg to provide 0, 10, 20 and 30 mg·kg -1 of supplemental Zn. In order to reduce the amount and the variability of their Zn stores, pigs were fed the basal diet for a 7-day adjustment period preceding a 19-day experimental period. Growth performance and bone bending moment were not affected by the level nor the source of zinc. On the contrary, plasma zinc concentration and alkaline phosphatase activity (P < 0.001), bone zinc concentration (P < 0.001), liver and empty body zinc concentrations (P < 0.01) as well as the amount of Zn retained estimated both by the balance technique (BT) (P < 0.001) and by the comparative slaughter technique (CST) (P < 0.01) increased linearly in response to supplemental Zn. However, the two Zn sources exhibited a similar bioavailability. Twenty-seven percent of Zn intake was retained when measured by means of the balance technique, regardless of the dietary level or zinc source. Zn retention was 54% lower when measured by means of the CST as compared to the BT. (0)2 23 48 50 80; e-mail: jondreville@st-gilles.rennes.inra.fr de croissance et le moment de flexion de l'os n'ont été affectés ni par le niveau ni par la source de zinc supplémentaire. Au contraire, la teneur en zinc et l'activité de la phosphatase alcaline du plasma (P < 0,001), les teneurs en zinc osseuse (P < 0,001), hépatique et corporelle (P < 0,01) ainsi que la quantité de zinc retenu estimée par la technique du bilan (P < 0,001) et celle des abattages comparés (P < 0,01) augmentaient linéairement avec l'addition du zinc. Cependant, aucune différence entre les sources n'a été détectée. Le coefficient de rétention de zinc, estimé par la technique du bilan, était de 27 % en moyenne, indépendamment du niveau ou de la source de zinc supplémentaire. Estimée par la technique des abattages comparés, la rétention de Zn était de 54 % inférieure à la valeur obtenue selon la technique du bilan.porc / zinc / biodisponibilité / source / indicateur

The Effects of Partially or Completely Substituted Dietary Zinc Sulfate by Lower Levels of Zinc Methionine on Growth Performance, Apparent Total Tract Digestibility, Immune Function, and Visceral Indices in Weaned Piglets

“…In addition, the Zn digestibility was also enhanced when at least 50 mg/kg inorganic Zn was replaced by ZnMet. It has been reported that increased apparent absorption and the retention of organic zinc sources were due to the different absorption pathways of different forms of Zn [22]. ZnMet can be absorbed in methionine absorption pathways and deposited together with methionine into the proteins of tissues [25], and this may be the reason for the enhancement of Zn digestibility in our results.…”

“…In the study of Case et al (2002), nursery pigs fed 500 mg/kg Zn from Zn-amino acid complexes grew faster than pigs fed 500 mg/kg inorganic Zn, but there was no difference compared with pigs fed 3000 mg/kg inorganic Zn [4]. These similar results are likely due to the enhanced bioavailability of organic Zn [22,23]. Moreover, the similar DM, OM and GE digestibility of piglets observed in this study demonstrated that complete replacement of 100 mg/kg inorganic Zn from ZnSO 4 with 50 mg/kg organic Zn from ZnMet had no adverse impact on the nutrient digestibility.…”

Bioavailability of Different Zinc Sources in Pigs 0–3 Weeks Post-Weaning

“…At a supplementary level of 100 mg Zn/kg, inorganic ZnO and ZnSO 4 did not exhibit lower bioavailability based on Zn ATTD and serum Zn status compared to the organic (Zn-Gly, AA-Zn, OH-Zn) or processed inorganic (Pot-Zn) sources of Zn. Revy et al [ 12 ] suggested that the lack of difference in bioavailability between inorganic and organic sources of Zn in some pig studies [ 32 , 33 , 34 ], including the present, in contrast to many poultry studies, may rely on the higher contents of phytate and calcium in poultry versus piglet diets. Thereby, poultry diets generally contain more dietary factors that can interact with and complex bind Zn ions in the gastrointestinal tract, and the beneficial effect of applying organic compared to inorganic sources of Zn on Zn bioavailability may be greater.…”

Long-term impact of zinc supplementation in sows: Impact on zinc status biomarkers and performance

“…34,36 Most other studies on the effect of dietary Zn levels found differences between treat- ment groups in plasma Zn [7][8][9][10] and liver and bone Zn concentration in sows 7,12,13,37 and piglets. 23,[38][39][40][41][42] Most of these studies, especially the studies on sows, compared the responses between a non-supplemented and supplemented treatment group without addition of phytase, though diets were (semi) purified or used to induce Zn deficiency and do not represent practical conditions. The dietary Zn concentration of the control group was lower (< 35 mg Zn per kg) in these studies than in the concentration of the non-supplemented diet with phytase in the present study during gestation (47 mg Zn per kg).…”