Armstrong T A, Cook D R, Ward M M, Williams C M, Spears J W
Department of Animal Science and Interdepartmental Nutrition Program, North Carolina State University, Raleigh 27695-7621, USA.
J Anim Sci. 2004 Apr;82(4):1234-40. doi: 10.2527/2004.8241234x.
In each of two experiments, 924 pigs (4.99 kg BW; 16 to 18 d of age) were assigned to 1 of 42 pens based on BW and gender. Pens were allotted randomly to dietary copper (Cu) treatments that consisted of control (10 ppm Cu as cupric sulfate, CuSO4 x 5H2O) and supplemental dietary Cu concentrations of 15, 31, 62, or 125 ppm as cupric citrate (CuCit), or 62 (Exp. 2 only), 125 (Exp. 1 only), or 250 ppm as CuSO4. Live animal performance was determined at the end of the 45-d nursery phase in each experiment. On d 40 of Exp. 2, blood and fecal samples were collected from two randomly selected pigs per pen for evaluation of plasma and fecal Cu concentrations and fecal odor characteristics. In Exp. 1, ADG, ADFI, and G:F were increased (P < 0.05), relative to controls, when pigs were fed diets containing 250 ppm Cu as CuSO4. Pigs fed diets containing 125 ppm Cu as CuCit had increased (P < 0.05) ADG compared with pigs fed diets supplemented with 15 or 62 ppm Cu as CuCit. The ADG, ADFI, and G:F did not differ among pigs fed diets containing 125 and 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. In Exp. 2, pigs fed diets containing 250 ppm Cu as CuSO4 had improved (P < 0.05) ADG, ADFI, and G:F compared with controls. In addition, ADG, ADFI, and G:F were similar when pigs were fed diets containing either 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. Pigs fed diets containing 62 ppm Cu as CuSO4 or CuCit had similar ADG, ADFI, and G:F. Plasma Cu concentrations were not affected by dietary Cu source or concentration, but fecal Cu concentrations were increased (P < 0.05) as the dietary concentration of Cu increased. Pigs consuming diets supplemented with 125 ppm Cu as CuCit had fecal Cu concentrations that were lower (P < 0.05) than pigs consuming diets supplemented with 250 ppm Cu as CuSO4. Fecal Cu did not differ in pigs receiving diets supplemented with 62 ppm Cu as CuSO4 or CuCit. Odor characteristics of feces were not affected by Cu supplementation or source. These data indicate that 125 and 250 ppm Cu gave similar responses in growth, and that CuCit and CuSO4 were equally effective at stimulating growth and improving G:F in weanling pigs. Fecal Cu excretion was decreased when 125 ppm Cu as CuCit was fed compared with 250 ppm Cu as CuSO4. Therefore, 125 ppm of dietary Cu, regardless of source, may provide an effective environmental alternative to 250 ppm Cu as CuSO4 in weanling pigs.
在两项实验中，根据体重和性别将924头猪（体重4.99千克；16至18日龄）分配到42个栏舍中的1个。栏舍被随机分配到不同的日粮铜（Cu）处理组，处理组包括对照组（10 ppm铜，以硫酸铜（CuSO₄·5H₂O）形式提供），以及补充日粮铜浓度为15、31、62或125 ppm的柠檬酸铜（CuCit）组，或者在实验2中为62 ppm（仅实验2）、实验1中为125 ppm或250 ppm的硫酸铜（CuSO₄）组。在每项实验的45天保育期结束时测定活体动物性能。在实验2的第40天，从每个栏舍中随机选择的2头猪采集血液和粪便样本，以评估血浆和粪便中的铜浓度以及粪便气味特征。在实验1中，与对照组相比，当给猪饲喂含250 ppm铜（以CuSO₄形式）的日粮时，平均日增重（ADG）、平均日采食量（ADFI）和料重比（G:F）增加（P < 0.05）。与饲喂补充15或62 ppm铜（以CuCit形式）日粮的猪相比，饲喂含125 ppm铜（以CuCit形式）日粮猪的ADG增加（P < 0.05）。在饲喂含125 ppm铜（以CuSO₄形式）、250 ppm铜（以CuSO₄形式）或125 ppm铜（以CuCit形式）日粮的猪之间，ADG、ADFI和G:F没有差异。在实验；2中，与对照组相比，饲喂含250 ppm铜（以CuSO₄形式）日粮的猪的ADG、ADFI和G:F有所改善（P < 0.05）。此外，当给猪饲喂含250 ppm铜（以CuSO₄形式）或125 ppm铜（以CuCit形式）的日粮时，ADG、ADFI和G:F相似。饲喂含62 ppm铜（以CuSO₄或CuCit形式）日粮的猪的ADG、ADFI和G:F相似。血浆铜浓度不受日粮铜来源或浓度的影响，但随着日粮铜浓度的增加，粪便铜浓度升高（P < 0.05）。与饲喂含250 ppm铜（以CuSO₄形式）日粮的猪相比，饲喂含125 ppm铜（以CuCit形式）日粮的猪的粪便铜浓度较低（P < 0.05）。在饲喂含62 ppm铜（以CuSO₄或CuCit形式）日粮的猪之间，粪便铜没有差异。粪便的气味特征不受铜补充剂或来源的影响。这些数据表明，125和250 ppm的铜在生长方面产生相似的反应，并且CuCit和CuSO₄在刺激断奶仔猪生长和改善料重比方面同样有效。与250 ppm铜（以CuSO₄形式）相比，饲喂125 ppm铜（以CuCit形式）时粪便铜排泄量减少。因此，在断奶仔猪中，125 ppm的日粮铜（无论来源如何）可能是250 ppm铜（以CuSO₄形式）的一种有效的环境替代物。
