Additivity of effects from dietary copper and zinc on growth performance and fecal microbiota of pigs after weaning1,2

Abstract

Four experiments were conducted to determine the interactive effects of pharmacological amounts of Zn from ZnO and Cu from organic (Cu-AA complex; Cu-AA) or inorganic (CuSO(4)) sources on growth performance of weanling pigs. The Cu was fed for 4 (Exp. 1) or 6 (Exp. 2, 3, and 4) wk after weaning, and Zn was fed for 4 (Exp. 1) or 2 (Exp. 2, 3, and 4) wk after weaning. Treatments were replicated with 7 pens of 5 or 6 pigs per pen (19.0 ± 1.4 d of age and 5.8 ± 0.4 kg of BW, Exp. 1), 12 pens of 21 pigs per pen (about 21 d of age and 5.3 kg of BW, Exp. 2), 5 pens of 4 pigs per pen (20.3 ± 0.5 d of age and 7.0 ± 0.5 kg of BW, Exp. 3), and 16 pens of 21 pigs per pen (about 21 d of age and 5.7 kg of BW, Exp. 4). In Exp. 1 and 2, Cu-AA (0 vs. 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 2 × 2 factorial arrangement. Only Exp. 1 used in-feed antibiotic (165 mg of oxytetracycline and 116 mg of neomycin per kilogram feed), and Exp. 2 was conducted at a commercial farm. In Exp. 3, sources of Cu (none; CuSO(4) at 250 mg/kg of Cu; and Cu-AA at 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 3 × 2 factorial arrangement. In Exp. 4, treatments were no additional Cu, CuSO(4) at 315 mg/kg of Cu, or Cu-AA at 100 mg/kg of Cu to a diet supplemented with 3,000 mg/kg of Zn from ZnO and in-feed antibiotic (55 mg of carbadox per kilogram of feed). In Exp. 1 and 2, both Zn and Cu-AA improved (P < 0.001 to P = 0.03) ADG and ADFI. No interactions were observed, except in wk 1 of Exp. 2, where Zn increased the G:F only in the absence of Cu-AA (Cu-AA × Zn, P = 0.04). A naturally occurring colibacillosis diarrhea outbreak occurred during this experiment. The ZnO addition reduced (P < 0.001) the number of pigs removed and pig-days on antibiotic therapy. In Exp 3, ADFI in wk 2 was improved by Zn and Cu (P < 0.001 and P = 0.09, respectively) with no interactions. In wk 1, G:F was reduced by ZnO only in the absence of Cu (Cu × Zn, P = 0.03). Feeding Zn decreased fecal microbiota diversity in the presence of CuSO(4) but increased it in the presence of Cu-AA (Cu source × Zn, P = 0.06). In Exp. 4, Cu supplementation improved the overall ADG (P = 0.002) and G:F (P < 0.001). The CuSO(4) effect on G:F was greater (P < 0.001) than the Cu-AA effect. Our results indicate that pharmacological amounts of ZnO and Cu (Cu-AA or CuSO(4)) are additive in promoting growth of pigs after weaning.

Supplementation of pigs diet with zinc and copper as alternative to conventional antimicrobials

“…Administration of Zn and Cu together usually does not cause additive effects, however, Perez et al (2011) observed appearance of additive effect of supplementation with pharmacological amounts of ZnO and CuSO 4 on weaning piglets growth. Shelton et al (2011) have shown advantages of inclusion of Zn and Cu in the pigs diet when Zn was added from 0 to 14 days postweaning and Cu from 14 to 42 days postweaning.…”

Alternatives to the use of antimicrobial agents in pig production: A multi-country expert-ranking of perceived effectiveness, feasibility and return on investment

“…Metals like copper and zinc are mentioned as potential alternatives in the literature too. They have been allowed as a (prescription) medicine in piglet feed in some European Union countries for several years, while in other EU countries is it not tolerated due to legal differences (Smith et al, 1998;Fard et al, 2010;Pérez et al, 2010;Mavromichalis, 2011; European Food Safety Authority (EFSA) panel on Additives Products or Substances used in Animal Feed (FEEDAP), 2012; Center of Expertise on Antimicrobial Consumption and Resistance in Animals (AMCRA), 2014c). Thacker (2013) addresses less traditional alternatives such as rare earth elements, clay minerals, antimicrobial peptides or essential oils and subsequently highlights the inconsistent results and the inferior effectiveness compared to antimicrobial agents of the majority of these compounds.…”

“…Use of genetically enhanced, high-resistance breeds or efforts towards eradication of diseases might also play a role in serving as alternatives to high usage of antimicrobial agents in pig production (Grol et al, 1990;Maes et al, 2007;Doeschl-Wilson et al, 2009;Opriessnig et al, 2009;Lunney and Chen, 2010;Pérez et al, 2010).…”

Effects of dietary copper, zinc, and ractopamine hydrochloride on finishing pig growth performance, carcass characteristics, and antimicrobial susceptibility of enteric bacteria12

“…Accordingly, although supplementation of both Cu and Zn at levels well above the pig's physiological requirements improve weaned pig performance (Pérez et al, 2011;Shelton et al, 2011), extended supplementation of minerals may lead to poor performance. Yet Kline et al (1972) reported no main or interactive effects of up to 500 mg/kg Cu and up to 300 mg/kg Zn on feed efficiency when fed from 17.3 to 90.8 kg.…”