Department of Morphology and Animal Physiology, São Paulo State University (UNESP), 14884-900 Jaboticabal, São Paulo, Brazil.
Cobb-Vantress, Siloam Springs, Arkansas, AR 72761, EUA, USA.
Poult Sci. 2018 Oct 1;97(10):3556-3563. doi: 10.3382/ps/pey221.
The pendulous crop is characterized by excessive distension of the crop musculature, compromising the bird's productivity and welfare. The etiology is still unknown, but it is believed that factors related to the birds' handling might be related to its incidence. The study was conducted in 2 environmental chambers. One was maintained at a comfortable temperature, while the other was set at a much lower temperature. In each chamber, animals were divided into 16 experimental pens (8 received mash feed and the others received pelletized feed) with a density of 12 birds/m2 (an expected stocking density of 32-36 kg/m2 after 42 d). The effects of rearing temperatures were evaluated in terms of broiler performance, specifically weight gain (kg), feed intake (kg), weekly feed intake (kg/wk), and feed conversion (kgfeed/kggrowth). The occurrences of pendulous crop were quantified every 2 d after the 14th day of rearing. Birds grown in thermal comfort and fed a pelletized ration were most susceptible (12%) to pendulous crop, followed by birds fed pelletized feed and reared in cold conditions (6.8%), and birds given mashed feed and reared at either temperature (about 3%). We concluded that feeding pelleted feed combined with warmer rearing temperatures may have caused some alteration of the gastrointestinal system of birds, which caused pendulous crop to be more prevalent.
悬雍垂作物的特点是作物肌肉过度膨胀，影响鸟类的生产力和福利。其病因尚不清楚，但据信与鸟类处理相关的因素与其发病率有关。这项研究是在 2 个环境室中进行的。一个保持在舒适的温度下，另一个则设置在低得多的温度下。在每个房间中，动物被分为 16 个实验笔（8 个接受磨碎饲料，另一些接受颗粒饲料），密度为 12 只/平方米（预计 42 天后达到 32-36 公斤/平方米的饲养密度）。饲养温度的影响是通过肉鸡的表现来评估的，具体指标是体重增加（kg）、饲料摄入量（kg）、每周饲料摄入量（kg/周）和饲料转化率（kg 饲料/kg 生长）。在饲养的第 14 天后，每两天就会对悬雍垂作物的发生情况进行量化。在热舒适条件下生长并喂食颗粒饲料的鸟类最容易发生悬雍垂作物（12%），其次是喂食颗粒饲料且在寒冷条件下饲养的鸟类（6.8%），以及在任何温度下喂食糊料的鸟类（约 3%）。我们得出结论，喂食颗粒饲料并结合更温暖的饲养温度可能导致鸟类的胃肠道系统发生一些变化，从而使悬雍垂作物更为普遍。
