Haley D B, Rushen J, Duncan I J, Widowski T M, De Passillé A M
Dairy and Swine Research and Development Centre, Agriculture and Agri-Food Canada, Lennoxville.
J Dairy Sci. 1998 Aug;81(8):2165-72. doi: 10.3168/jds.S0022-0302(98)75794-7.
This study examined effects of resistance to milk flow and the provision of hay on the duration of nutritive sucking and subsequent nonnutritive sucking by dairy calves. In a series of four experiments, 12 male Holstein calves were individually fed milk from an artificial teat. Resistance to milk flow was varied by adjusting the orifice size within the milk supply tube. Using a Latin square design, each calf was fed the same quantity of milk using four orifice sizes (one per day for 4 consecutive d). The duration of nutritive sucking (time required to finish the milk meal) was longer when calves were fed from the smallest orifice size (0.16-cm diameter) than when calves were fed from the largest orifice size (0.55-cm diameter). Calves compensated for resistance to milk flow in an attempt to maintain milk intake; however, changes in sucking rate alone were probably not responsible for observed differences in the rate of milk consumption from different orifice sizes. The duration of nonnutritive sucking (sucking of the teat following the milk meal) was significantly reduced when calves were fed from the smallest orifice compared with that when calves were fed from the largest orifice. Nonnutritive sucking was reduced but not eliminated even with the longest meal duration. The provision of hay to calves following the meal also significantly reduced the amount of nonnutritive sucking. Reduction in flow rate when calves drink milk through a teat and the provision of hay after the meal can reduce the incidence of nonnutritive sucking following the meal and may help to limit cross-sucking in group housing systems.
本研究考察了牛奶流速阻力以及干草供应对犊牛营养性吸吮持续时间和随后非营养性吸吮的影响。在一系列四个实验中，12头雄性荷斯坦犊牛通过人工乳头单独饲喂牛奶。通过调整供奶管内的孔口大小来改变牛奶流速阻力。采用拉丁方设计，每头犊牛使用四种孔口大小（连续4天每天一种）饲喂相同量的牛奶。当犊牛从最小孔口大小（直径0.16厘米）饲喂时，营养性吸吮的持续时间（喝完一顿奶所需的时间）比从最大孔口大小（直径0.55厘米）饲喂时更长。犊牛会补偿牛奶流速阻力以维持牛奶摄入量；然而，仅吸吮速率的变化可能并非导致不同孔口大小下牛奶消耗速率出现观察到差异的原因。与从最大孔口饲喂的犊牛相比，从最小孔口饲喂的犊牛非营养性吸吮的持续时间显著减少。即使进餐时间最长，非营养性吸吮也只是减少而非消除。在餐后给犊牛提供干草也显著减少了非营养性吸吮的量。当犊牛通过乳头喝牛奶时流速降低以及餐后提供干草可以减少餐后非营养性吸吮的发生率，并可能有助于限制群体饲养系统中的交叉吸吮。
