Reynolds F H, Forbes J M, Miller H M
Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK.
Animal. 2010 Aug;4(8):1359-67. doi: 10.1017/S1751731110000327.
An experiment was conducted to examine whether weaned piglets would display preference for a food containing a pharmacological level of zinc oxide (ZnO). A total of 60 piglets were weaned at 7.8 kg ± 0.14 (s.e.m.) and 27.8 ± 0.11 days of age into eight mixed sex groups of seven or eight piglets per pen. Groups were balanced for litter origin, weaning weight and sex. Piglet feeding behaviour was constantly recorded by a multi-spaced feeding behaviour recording system (Leeds University Feeding Behaviour System) in each pen. Each pen of pigs was offered ad libitum access to two different foods (16.2 MJ digestible energy, 16 g lysine/kg), which differed only in the level of ZnO supplementation: unsupplemented (U) or supplemented (Z; ZnO 3100 mg/kg). Both foods contained a basal level of zinc (100 mg/kg). Feeding time was recorded for each individual at each trough. Piglets were weighed at weaning and at 7 and 13 days thereafter. The experiment ran for 13 days. Any piglet observed with post-weaning scour (Y) was recorded and treated appropriately whereas healthy piglets were categorised as N (no scour). Preference for a food was defined as being significantly different from 50% of total feed intake or time spent feeding. There was no difference between piglet numbers selecting each food as their first meal. However, within the first 24 h, piglets preferred (P < 0.001) food U, spending only 36.3% (32.2 to 40.5; 95% confidence interval) of feeding time at food Z. Throughout the experiment, piglets showed aversion (P < 0.001) to food Z, consumption being 8.9% (5.1 to 13.6) and 15.7% (8.9 to 23.9) of total intake in weeks 1 and 2, respectively. Individual piglets showed their preference for food U with only 16.6% (14.6 to 18.5) and 21.8% (19.6 to 24.0) of feeding time spent on food Z in weeks 1 and 2, respectively. Scouring piglets did not show any difference in feeding behaviour from healthy piglets in either week. Average piglet gain (of all piglets) was low, at 0.039 ± 0.03 and 0.272 ± 0.04 kg/day in weeks 1 and 2, respectively. Given a choice, weaned piglets showed a clear preference for the food U even when exhibiting post-weaning scour. It can be concluded that the newly weaned, naïve, piglet is not able to recognise a food with clear health and performance benefits but selected the food U due to the reduced palatability of the food Z.
进行了一项实验，以研究断奶仔猪是否会对含有药理学水平氧化锌（ZnO）的食物表现出偏好。总共60头仔猪在体重7.8 kg±0.14（标准误）、年龄27.8±0.11天时断奶，分成8个混合性别组，每组7或8头仔猪，每栏饲养。各组在窝别来源、断奶体重和性别方面保持均衡。通过多空间采食行为记录系统（利兹大学采食行为系统）持续记录每栏仔猪的采食行为。每栏猪可随意采食两种不同的食物（消化能16.2 MJ，赖氨酸16 g/kg），这两种食物仅在氧化锌添加水平上有所不同：未添加（U）或添加（Z；氧化锌3100 mg/kg）。两种食物都含有基础水平的锌（100 mg/kg）。记录每头仔猪在每个食槽的采食时间。在断奶时以及断奶后7天和13天对仔猪进行称重。实验持续13天。记录任何观察到有断奶后腹泻（Y）的仔猪，并进行适当治疗，而健康仔猪归类为N（无腹泻）。对一种食物的偏好定义为与总采食量或采食时间的50%有显著差异。选择每种食物作为第一餐的仔猪数量没有差异。然而，在最初的24小时内，仔猪更喜欢（P<0.001）食物U，在食物Z上的采食时间仅占36.3%（32.2至40.5；95%置信区间）。在整个实验过程中，仔猪对食物Z表现出厌恶（P<0.001），在第1周和第2周的摄入量分别占总摄入量的8.9%（5.1至13.6）和15.7%（8.9至23.9）。个体仔猪表现出对食物U的偏好，在第1周和第2周，在食物Z上的采食时间分别仅占16.6%（14.6至18.5）和21.8%（19.6至24.0）。腹泻仔猪在任何一周的采食行为与健康仔猪均无差异。所有仔猪的平均增重较低，第1周和第2周分别为0.039±0.03和0.272±0.04 kg/天。在有选择的情况下，断奶仔猪即使出现断奶后腹泻，也对食物U表现出明显的偏好。可以得出结论，刚断奶的、未接触过的仔猪无法识别具有明显健康和生产性能益处的食物，而是由于食物Z适口性降低而选择了食物U。
