Abstract

This study analysed potential associations between the prevalence of rumen, abomasum, liver, and claw disorders detected in 26 batches of Holstein veal calves through a post-mortem inspection at the slaughterhouse, and on-farm mortality and feeding management data. Organs of 15–16 calves per batch (16.5 rumens, 15.9 abomasa, 15.1 livers, and 31.1 claws) were inspected by 3 veterinarians in the slaughter-line. ‘Batch’ refers to group of calves belonging to the same farm and slaughter group. Hyperkeratosis and plaques were detected in over 60% of rumens per batch, and some cases, in all rumens. More than 85% of abomasa showed ulcerations. Sole haemorrhages were detected in 64 to 97% of claws. During fattening, calves received on average 312 kg of milk-replacer (MR) and 162 kg of solid feed (SF), composed mainly of corn grain (85–93% as-fed basis). Rumens with hyperkeratosis were positively correlated to the percentage of corn grain. Abomasa with large-sized-lesions in the pyloric area were positively correlated to the SF amount. Ulcerated abomasa were positively correlated to calves’ mortality reported by farmers. Cluster analysis identified 3 feeding plans. The first, based on MR administration and moderate SF amount, produced lighter carcasses and low-developed rumens, but reduced the prevalence of rumen hyperkeratosis and sole haemorrhages; the other two, more ‘aggressive’ by increasing the amount of SF or both SF and MR, produced heavier carcasses but worsened rumen and claw conditions. This study suggests the existence of different feeding practices used by veal producers that should be reviewed to improve calves’ welfare.

• Highlights

• Feeding plans based on moderate amount of solid feed together with the liquid diet reduce the prevalence of rumen alterations and sole haemorrhages

• The provision of greater amount of high-grain solid feed throughout the fattening rises the prevalence of rumen hyperkeratosis and sole haemorrhages

• None of the feeding plans were capable of decreasing the occurrence of abomasal ulcerations, which were positively associated with on-farm mortality

摘要

这项研究通过在屠宰场进行尸检和农场分析，分析了在26批次的荷斯坦犊牛犊中检测到的瘤胃，厌恶，肝和爪疾病的患病率之间的潜在关联死亡率和喂养管理数据。每批15-16头犊牛的器官（16.5个瘤胃，15.9个肉瘤，15.1个肝脏和31.1个爪）在屠宰线上由3名兽医检查。“批次”是指属于同一农场和屠宰组的一组犊牛。每批次瘤胃中有60％以上检测到过度角化和斑块，在某些情况下，所有瘤胃中都检测到。超过85％的阿玛玛人有溃疡。在64％到97％的爪子中发现了唯一的出血。在育肥过程中，小牛平均接受312公斤的代乳奶（MR）和162公斤的固体饲料（SF），主要由玉米粒组成（进食量的85-93％）。角化过度的瘤胃与玉米粒的百分比呈正相关。幽门区域大病变的阿波玛莎与SF含量呈正相关。溃疡性的肉瘤与农民报告的犊牛死亡率呈正相关。聚类分析确定了3个喂养计划。第一种是基于MR给药和适度的SF量，产生了较轻的car体和低度的瘤胃，但降低了瘤胃过度角化和单一出血的发生率。另外两个，通过增加SF或同时增加SF和MR的量而更具“侵略性”，产生了较重的car体，但使瘤胃和爪状状况恶化。这项研究表明，小牛肉生产者采用了不同的喂养方式，应该对其进行审查以提高犊牛的福利。但降低了瘤胃过度角化和单纯出血的发生率；另外两个，通过增加SF或同时增加SF和MR的量而更具“侵略性”，产生的he体较重，但瘤胃和爪状状况恶化。这项研究表明，小牛肉生产者采用了不同的喂养方式，应该对其进行审查以提高犊牛的福利。但降低了瘤胃过度角化和单纯出血的发生率；另外两个，通过增加SF或同时增加SF和MR的量而更具“侵略性”，产生的he体较重，但瘤胃和爪状状况恶化。这项研究表明，小牛肉生产者采用了不同的喂养方式，应该对其进行审查以提高犊牛的福利。

• 强调

• 以适量的固体饲料和流质饮食为基础的喂养计划可降低瘤胃变化和唯一出血的发生率

• 在整个育肥过程中提供更多的高谷物固体饲料，会增加瘤胃角化过度和单纯出血的发生率

• 没有一项喂养计划能够减少与农场死亡率成正相关的肉瘤溃疡的发生