The Institute for Agricultural and Fisheries Research (ILVO), Technology and Food Science Unit, Agricultural Engineering, 9820 Merelbeke, Belgium.
The Institute for Agricultural and Fisheries Research (ILVO), Technology and Food Science Unit, Agricultural Engineering, 9820 Merelbeke, Belgium.
J Dairy Sci. 2012 Sep;95(9):4978-4988. doi: 10.3168/jds.2011-5296.
Traditionally, all cows within a herd are milked with the same teat cup liner, although it is hypothesized that considerable variation in teat dimensions exists between cows and quarters within cows. To study at which level (herd, cow, or quarter) most variation in teat dimensions resides, and to identify factors explaining (part of) this variation, both a cross-sectional (n=2,715) and a longitudinal study (n=8,678) were conducted. Using an objective and easy-to-use measuring device, teat length and teat diameters were determined. In both studies, most variation in teat dimensions was present at the cow or within-cow level, and not at the herd level, indicating that choosing a teat cup liner that is identical for all cows in a herd is far from optimal. Quarter position (front versus hind), parity and lactation stage were identified as factors associated with teat length and teat diameters. Generally, front teats were longer and broader than hind teats. Teat length and diameters increased with parity, although the increase in teat length was not significant from second parity onwards in front teats, based on observations from the longitudinal study. After the first 30 d in milk, teat length substantially and significantly increased, whereas teat diameters decreased. We conclude that better results in teat condition, and eventually in udder health, might be yielded when different teat cup liners are chosen for front versus hind teats or for cows of different parity or lactation stage, with special attention to the first 30 d in milk. However, the biological relevance of these differences should be examined first.
传统上，同一头奶牛的所有奶头都使用相同的乳杯衬垫进行挤奶，但据推测，奶牛之间以及奶牛的各个乳区之间的乳头部尺寸存在相当大的差异。为了研究乳头部尺寸的变异主要存在于哪个水平（牛群、奶牛或乳区），并确定解释（部分）这种变异的因素，进行了横断面（n=2715）和纵向研究（n=8678）。使用客观易用的测量设备，确定了乳头部的长度和直径。在这两项研究中，乳头部尺寸的大部分变异存在于奶牛或奶牛内部，而不是在牛群水平上，这表明为牛群中的所有奶牛选择相同的乳杯衬垫远非最佳选择。乳区位置（前区与后区）、胎次和泌乳阶段被确定为与乳头部长度和直径相关的因素。一般来说，前乳区的乳头部比后乳区的更长更宽。乳头部长度和直径随着胎次的增加而增加，尽管基于纵向研究的观察，在前乳区，从第二胎次开始，乳头部长度的增加不再显著。在产奶的头 30 d 后，乳头部长度显著增加，而直径减小。我们得出的结论是，当为前区与后区的乳区或不同胎次或泌乳阶段的奶牛选择不同的乳杯衬垫时，可能会在乳区状况，最终在乳房健康方面取得更好的效果，特别是在产奶的头 30 d 期间，应特别注意。然而，应该首先检查这些差异的生物学相关性。
