Remus Aline, Hauschild Luciano, Létourneau-Montminy Marie-Pierre, Andretta Ines, Pomar Candido
School of Agricultural and Veterinary Studies, Department of Animal Science, São Paulo State University, São Paulo, São Paulo, Brazil.
Department of Animal Science, Université Laval, Quebec City, Quebec, Canada.
Transl Anim Sci. 2020 Sep 24;4(4):txaa177. doi: 10.1093/tas/txaa177. eCollection 2020 Oct.
Feeding behavior is an important aspect of pig husbandry as it can affect protein deposition (PD) in pigs. A decrease in plasma threonine (Thr) levels may influence feed intake (FI) due to amino acid imbalance. We set out to study whether different Thr inclusion rates of 70%, 85%, 100%, 115%, and 130% of the ideal Thr:lysine (Lys) ratio of 0.65 in two different feeding programs (individual precision feeding and group-phase feeding could affect pig feeding behavior and consequently PD. Two 21-d trials were performed in a 2 × 5 factorial setup (feeding systems × Thr levels) with 110 pigs in the growing phase [25.0 ± 0.8 kg of body weight (BW)] and 110 pigs in the finishing phase (110.0 ± 7.0 kg BW), which correspond to 11 pigs per treatment in each trial. Pigs were housed in the same room and fed using computerized feeding stations. The total lean content was estimated by dual x-ray absorptiometry at the beginning (day 1) and the end (day 21) of the trial. Multivariate exploratory factor analysis was performed to identify related variables. Confirmatory analysis was performed by orthogonal contrasts and Pearson correlation analysis. Graphical analysis showed no difference in feeding patterns between feeding systems during the growing or finishing phase. Pigs exhibited a predominant diurnal feeding, with most meals (73% on average) consumed between 0600 and 1800 h. Exploratory factor analysis indicated that feeding behavior was not related to growth performance or PD in growing or finishing pigs. Changes in feeding behavior were observed during the growing phase, where increasing dietary Thr resulted in a linear increase in the FI rate ( < 0.05). During the finishing phase, the duration of the meal and FI rate increased linearly as dietary Thr increased in the diet ( < 0.05). These changes in feeding behavior are, however, correlated to BW. In conclusion, the exploratory factor analysis indicated that feeding behavior had no correlation with growth performance or protein and lipid deposition in growing or finishing pigs. Dietary Thr levels and feeding systems had no direct effect on FI.
采食行为是养猪生产中的一个重要方面，因为它会影响猪的蛋白质沉积（PD）。血浆苏氨酸（Thr）水平的降低可能由于氨基酸失衡而影响采食量（FI）。我们着手研究在两种不同的饲养方案（个体精准饲喂和群体分阶段饲喂）中，理想的Thr:赖氨酸（Lys）比例0.65的70%、85%、100%、115%和130%这几种不同的Thr添加率是否会影响猪的采食行为，进而影响蛋白质沉积。在生长阶段（体重25.0±0.8千克）的110头猪和育肥阶段（体重110.0±7.0千克）的110头猪中，以2×5析因设计（饲养系统×Thr水平）进行了两项为期21天的试验，每个试验中每个处理有11头猪。猪饲养在同一房间，使用电脑控制的饲喂站进行饲喂。在试验开始（第1天）和结束（第21天）时，通过双能X线吸收法估计总瘦肉含量。进行多变量探索性因子分析以识别相关变量。通过正交对比和Pearson相关分析进行验证性分析。图形分析表明，在生长或育肥阶段，不同饲养系统之间的采食模式没有差异。猪表现出明显的昼夜采食模式，大多数采食（平均73%）发生在06:00至18:00之间。探索性因子分析表明，生长或育肥猪的采食行为与生长性能或蛋白质沉积无关。在生长阶段观察到采食行为的变化，日粮Thr增加导致采食量增加率呈线性增加（P<0.05）。在育肥阶段，随着日粮中Thr增加（P<0.05），采食餐次的持续时间和采食量增加率呈线性增加。然而，这些采食行为的变化与体重相关。总之，探索性因子分析表明，生长或育肥猪的采食行为与生长性能或蛋白质和脂肪沉积无关。日粮Thr水平和饲养系统对采食量没有直接影响。
