Yamauchi Yuki, Yoshida Shu, Matsuyama Hiroyuki, Obi Takeshi, Takase Kozo
Department of Veterinary Medicine, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
Chemical Division, Enuchicken Co., Ltd., 3669 Kori Chiran-cho Minamikyushu-shi, Kagoshima 897-0302, Japan.
J Vet Med Sci. 2017 Sep 12;79(9):1466-1471. doi: 10.1292/jvms.17-0287. Epub 2017 Jul 31.
A survey of beak morphological abnormalities was performed on 6,201 chickens (egg-laying hens and chickens for meat production belonging to 25 flocks) brought to a poultry processing plant. The observed abnormalities varied among flocks with occurrence rates ranging from 0.48 to 46.67%. The occurrence was high in flocks subjected to beak trimming and varied significantly according to chicken breed, with the highest rates of abnormalities in a certain chicken breed. The most widely observed abnormalities were: 1) uneven growth of the upper and lower mandibles, mostly with elongation of the lower mandible (accounting for 64.8% of all abnormalities); 2) misalignment of the upper and lower mandibles, causing lateral deviation or crossing (16.3%); 3) sharp or jagged deformities of the mandible tips (10.1%); 4) permanent open beak, a deformity in which the beak did not close completely even when closed (5.8%); and 5) formation of tubercular swellings at the tips of the upper or lower mandibles (3.1%). This is the first report on the occurrence of beak abnormalities in beak-trimmed poultry in Japan.
对送至一家家禽加工厂的6201只鸡（属于25个鸡群的产蛋母鸡和肉鸡）进行了喙部形态异常调查。观察到的异常情况在不同鸡群中有所不同，发生率在0.48%至46.67%之间。在接受喙部修剪的鸡群中发生率较高，并且根据鸡的品种差异显著，某一鸡品种的异常发生率最高。最常观察到的异常情况为：1）上下颌生长不均，以下颌伸长居多（占所有异常情况的64.8%）；2）上下颌错位，导致侧向偏移或交叉（16.3%）；3）下颌尖端尖锐或呈锯齿状畸形（10.1%）；4）永久性张口，即即使闭嘴时喙也不能完全闭合的畸形（5.8%）；5）在上颌或下颌尖端形成结节状肿胀（3.1%）。这是日本关于喙部修剪家禽中喙部异常发生情况的首份报告。
