Hyun Y, Ellis M
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
J Anim Sci. 2001 Apr;79(4):803-10. doi: 10.2527/2001.794803x.
The effects of four group sizes (2, 4, 8, and 12 pigs per pen) and two single-space feeder types (conventional and electronic feed intake recording equipment [FIRE]) on feed intake, growth performance, and feeding patterns were determined in growing pigs over a 4-wk period. A total of 416 hybrid pigs (barrows and gilts) were grown from 26.5 (SD = 1.6) to 47.8 (SD = 2.7) kg BW and given ad libitum access to a corn-soybean meal-based diet (17.4% CP; 0.9% lysine; 3,298 kcal ME/kg). The floor space allowance was 0.9 m2/pig for all treatments. Pigs using the electronic feeders had similar growth rates but lower feed intakes (P < 0.01) and higher gain:feed ratios (P < 0.01) compared to those using the conventional feeders. Barrows compared to gilts had higher growth rates (P < 0.05), numerically higher (P > 0.05) ADFI, and similar feed efficiency and feeding pattern. Feed intakes and growth rates were lowest (P < 0.05) for groups of 12 pigs but gain:feed ratio was not affected by group size. Daily feeder occupation time per pig was lower (P < 0.01) for groups of 12 than for groups of 2 or 4 pigs, and feed consumption rate was higher (P < 0.01) for groups of 12 than for groups of 4 pigs. The proportion of time spent eating was lower (P < 0.01) and the proportion of time spent standing was higher (P < 0.01) for pigs in groups of 12 compared to groups of 2. Correlations between ADG and ADFI and feed intake per visit were 0.29 and 0.30, respectively (P < 0.01), between ADG and ADFI and feed consumption rate were 0.27 and 0.31, respectively (P < 0.01), and between ADFI and feeder occupation time per day were 0.33 (P < 0.01). This study suggests that, in growing pigs given access to a single feeder, changes in feeding behavior with increasing group size were not sufficient to maintain feed intake and growth rate.
在4周的时间里，研究了四种饲养密度（每栏2头、4头、8头和12头猪）和两种单空间饲槽类型（传统饲槽和电子采食量记录设备[FIRE]）对生长猪采食量、生长性能和采食模式的影响。总共416头杂种猪（阉公猪和后备母猪）体重从26.5（标准差 = 1.6）千克增长到47.8（标准差 = 2.7）千克，自由采食以玉米 - 豆粕为基础的日粮（粗蛋白17.4%；赖氨酸0.9%；代谢能3298千卡/千克）。所有处理的每头猪占地面积均为0.9平方米。与使用传统饲槽的猪相比，使用电子饲槽的猪生长速度相似，但采食量较低（P < 0.01），料重比更高（P < 0.01）。阉公猪与后备母猪相比，生长速度更高（P < 0.05），日均采食量在数值上更高（P > 0.05），饲料效率和采食模式相似。12头猪一组的采食量和生长速度最低（P < 0.05），但料重比不受饲养密度影响。每头猪每天在饲槽处停留的时间，12头猪一组比2头或4头猪一组更低（P < 0.01），饲料消耗速度12头猪一组比4头猪一组更高（P < 0.01）。与2头猪一组相比，12头猪一组的猪采食时间比例更低（P < 0.01），站立时间比例更高（P < 0.01）。平均日增重与日均采食量以及每次采食的采食量之间的相关性分别为0.29和0.30（P < 0.01），平均日增重与日均采食量以及饲料消耗速度之间的相关性分别为0.27和0.31（P < 0.01），日均采食量与每天在饲槽处停留时间之间的相关性为0.33（P < 0.01）。本研究表明，在使用单个饲槽的生长猪中，随着饲养密度增加，采食行为的变化不足以维持采食量和生长速度。
