摘要
Abomasal damage is a known health issue in intensive veal production and is associated with improper housing and feeding. Grass-based veal production could be an improvement, as access to pasture allows the expression of natural behaviors, such as species-specific foraging, and thus can contribute to calf welfare. However, data on the abomasal health of grazed calves have not yet been reported. As feed composition can affect the severity of mucosal damage, we compared the abomasa of calves that grazed on 2 swards with different plant composition. From 2018 to 2020, 111 calves of 2 dairy breeds, German Holstein and Jersey, were kept in whole-day strip grazing on these swards. Calves were sampled regularly for intestinal parasites and anthelmintic drug use was recorded. The animals were slaughtered at an age of 32 ± 2 wk (mean ± standard deviation) after individually varying grazing periods of 75 ± 22 d. After slaughter, dissection revealed that 104 of the 111 abomasa displayed low-grade nonperforating lesions, which were primarily located in the pyloric part. A more severe nonperforating lesion was registered in one calf only. In 46 abomasa, we observed diffuse inflammation. This inflammation was characterized by normal mucosal rugae but with slight discoloration that varied in the degree of redness and proliferation of the mucosa. Sward composition and breed did not affect the occurrence of abomasal lesions, but treatment with anthelmintics was negatively correlated with diffuse inflammation. Compared with the abomasa of calves fed under intensive conditions, the abomasa of calves kept on pasture in this study were not as severely altered, but completely unaffected abomasa were rarely observed either. This raises the question to what extent the observed changes in the abomasum were caused by husbandry and feeding conditions or whether they correspond to the normal condition of grazing animals.
摘要译文
憎恶的损害是强化小牛肉生产中已知的健康问题，与不当住房和饲料有关。基于草的小牛肉的生产可能是一种改进，因为获得牧场可以表达自然行为，例如特定于物种的觅食，因此可以有助于小牛福利。但是，尚未报道有关放牧小牛的憎恶健康的数据。由于饲料组成可能会影响粘膜损伤的严重程度，因此我们比较了在2种具有不同植物组成的草皮上放牧的犊牛的bomasa。从2018年到2020年，德国荷斯坦和泽西岛有111只犊牛在这些草皮上放牧的全天脱衣舞。定期采样犊牛的肠道寄生虫，并记录驱虫药的使用。在分别变化的放牧期为75±22 d之后，将动物在32±2 wk（平均值±标准偏差）时被宰杀。屠宰后，解剖表明，111个bomasa中有104个显示出低度的非伪造病变，这些病变主要位于幽门部位。仅在一只小牛中注册了更严重的非孔损伤。在46个Abomasa中，我们观察到弥漫性炎症。这种炎症的特征是正常的粘膜皱纹，但略微变色在粘膜的发红程度和增殖程度上有所不同。草的成分和品种不会影响憎恶的病变的发生，但是用驱虫药的治疗与弥漫性炎症负相关。与在密集条件下喂养的犊牛的库玛萨相比，这项研究中饲养的犊牛的bomasa并没有那么严重改变，但很少观察到完全未受影响的bomasa。这就提出了一个问题，在多大程度上观察到的肥胖的变化是由饲养和喂养条件引起的，或者它们是否与放牧动物的正常状况相对应。
Kerstin Barth [1]. Pasture-based fattening does not cause severe nonperforating lesions in veal calves of dairy breeds[J]. JDS Communications, 2023,4(6): 496-501