Behaviour of lame cows: a review

Claw horn disorders, infectious diseases of hooves and leg injuries cause lameness in dairy cows. However, such diseases as sole haemorrhages, sole ulcers or white line diseases, cause clinical lameness. Lameness reduces milk production, the fertility of cows and also causes earlier culling of cows, as well resultings in a deterioration of their welfare. In this review we focus on the impact of lameness on bovine behaviour. The time spent lying down is an important behaviour of dairy cows. As an increased locomotion score is associated with an increased percentage of cows lying down, also the position of cows within the milking parlour is associated with lameness. Lame cows are more likely to present toward the end of milking. Clinical lameness is a chronic stressor, reducing progesterone concentrations prior to oestrus, and resulting in reduced sexual behaviour; however, lame cows have the same potential period of oestrus when compared with non-lame cows. Hoof diseases, particularly those which are a source of pain, also reduce animal welfare. A high standard of cow welfare may be achieved by improving the lives of animals and the people who work with them. A lack of comfort while lying presents a significant risk for lameness. Improvements in comfort on more than 75% of farms (32 out of a total number of 53 farms) reduced the incidence of mastitis, while on 42 farms it reduced the prevalence of lameness. The keeping of cows on the straw bed of stalls does not only improve animal welfare, mainly through the greater comfort of the floor, but has also been showed to increase eating and ruminating behaviour. Cows also prefer straw to sand bedding and lay down longer on straw than on sand; however, cleanliness and hoof health have been shown to be better on sand. Apart from comfort, the main factors which promote improvements in bovine welfare and health, include good management of dairy farms, keeping cows in free stalls with accompanying regular exercise, and a long time spent at pasture. The prevalence of clinical lameness was demonstrated to be higher on farms using mattresses when compared with farms using deep-bedded stalls. No differences were found in behaviour among cows with different degrees of lameness housed in mattress stalls. Hence, measures of laying behaviour are not good indicators of lameness.