Which of the following is a side effect of docking a lamb's tail too short?

Docking a lamb's tail too short can lead to rectal prolapse, which is a serious condition where the rectum becomes displaced and protrudes from the body. This occurs because the tail helps to support the integrity of the surrounding tissue and structures in the area. When the tail is docked excessively, there may be a loss of support for the muscles and tissues that hold the rectum in its proper position. This displacement can create significant health issues for the lamb, requiring immediate veterinary attention.

While other side effects such as constipation, infection, and loss of appetite can occur under certain conditions, they are not directly caused by excessively short tail docking. Rectal prolapse stands out as a more direct consequence of improper docking, making it the most relevant and concerning side effect associated with this procedure. Hence, understanding the implications of docking practices is crucial for the welfare of livestock.