Guzmán-Pino S A, Solà-Oriol D, Davin R, Manzanilla E G, Pérez J F
J Anim Sci. 2015 Jun;93(6):2840-8. doi: 10.2527/jas.2014-8380.
A total of 672 male and female piglets (21 d postweaning; approximately 13 kg BW) were selected to be used in 3 different experiments to assess the influence of dietary electrolyte balance (dEB; Na + K - Cl, in mEq/kg of diet) on feed preference and growth performance. In Exp. 1, piglets were fed 4 isoenergetic diets differing in dEB level: 16, 133, 152, and 269 mEq/kg diets. Changes on dEB were obtained by changing the levels of sodium and chloride with calcium chloride, calcium carbonate, and sodium bicarbonate. Piglets fed the 16 and 133 mEq/kg diets achieved a greater ADG (P < 0.04), BW (P < 0.04), and apparent total-tract digestibility of CP and Zn (P < 0.05) than did piglets fed the 269 mEq/kg diet. The 16 mEq/kg level also reduced blood total CO (P < 0.01), bicarbonate (P < 0.01), and base excess (P < 0.02) concentrations compared with the rest of the dietary treatments. Three diets differing in dEB were designed for Exp. 2 and 3: -16, 151, and 388 mEq/kg diets. In Exp. 2, greater ADFI (P = 0.03), BW (P = 0.02), ADG (P < 0.001), and G:F (P < 0.01) were observed for piglets fed the -16 mEq/kg diet than those fed the 388 mEq/kg diet. Subsequently, their short-term preference for these diets was assessed by using a 2-d choice-test protocol (30 min). Piglets preferred (P < 0.001) the 388 mEq/kg diet to the -16 mEq/kg diet, independently of the dietary treatment they received before. Pigs also preferred (P < 0.001) the 151 mEq/kg diet when compared with the -16 mEq/kg diet. Experiment 3 assessed the long-term preference and short-term consumption of the -16 and 388 mEq/kg diets. Similar to Exp. 2, animals showed a greater (P < 0.001) intake of the 388 mEq/kg diet than they did of the -16 mEq/kg diet during both the preference (14 d) and 1-feeder (2 h) tests conducted. Results show that low rather than high dEB levels optimize growth performance of piglets. When they have the opportunity to choose, piglets are unable to select the diet that optimizes their performance, either in short- or in long-term preference tests, showing also a greater short-term consumption of high instead of low dEB levels.
总共672头断奶后21天的雌雄仔猪（体重约13千克）被挑选出来用于3个不同实验，以评估日粮电解质平衡（dEB；钠+钾-氯，单位为毫当量/千克日粮）对饲料偏好和生长性能的影响。在实验1中，给仔猪饲喂4种等能量日粮，其dEB水平不同：分别为16、133、152和269毫当量/千克日粮。通过用氯化钙、碳酸钙和碳酸氢钠改变钠和氯的水平来改变dEB。与饲喂269毫当量/千克日粮的仔猪相比，饲喂16和133毫当量/千克日粮的仔猪日增重（P<0.04）、体重（P<0.04）以及粗蛋白和锌的表观全肠道消化率更高（P<0.05）。与其他日粮处理相比，16毫当量/千克水平的日粮还降低了血液中总二氧化碳（P<0.01）、碳酸氢盐（P<0.01）和碱剩余（P<0.02）的浓度。为实验2和实验3设计了3种dEB不同的日粮：-16、151和388毫当量/千克日粮。在实验2中，与饲喂388毫当量/千克日粮的仔猪相比，饲喂-16毫当量/千克日粮的仔猪采食量更高（P=0.03）、体重（P=0.02）、日增重（P<0.001）和料重比更高（P<0.01）。随后，通过使用为期2天的选择测试方案（30分钟）评估它们对这些日粮的短期偏好。无论之前接受何种日粮处理，仔猪都更偏好（P<0.001）388毫当量/千克日粮而非-16毫当量/千克日粮。与-16毫当量/千克日粮相比，仔猪也更偏好（P<0.001）151毫当量/千克日粮。实验3评估了-16和388毫当量/千克日粮的长期偏好和短期摄入量。与实验2类似，在偏好测试（14天）和单饲测试（2小时）期间，动物对388毫当量/千克日粮的摄入量均高于-16毫当量/千克日粮（P<0.001）。结果表明，低dEB水平而非高dEB水平能优化仔猪生长性能。当有机会选择时，无论是在短期还是长期偏好测试中，仔猪都无法选择能优化其性能的日粮，而且在短期摄入中，它们对高dEB水平日粮的摄入量高于低dEB水平日粮。
