Observational and Experimental Studies of the Influence of Housing Factors on the Behaviour and Health of Dairy Cows

Livestock housing conditions are an important determinant of animal behaviour and health. The objective of the present work was to elucidate the influence of some important housing factors on the occurrence of production diseases in dairy cattle and to clarify the relationship between experimental and observational methods in the study of disease patterns in dairy herds. The importance of the animals’ cleanliness is emphasized and consequences for their behaviour, cleanliness, health and well-being of different types of tie-stall equipment are considered. In particular, the influence of electric cow-trainers on the animals’ health and welfare is discussed in light of the present work and previous research. Important effects on foot, leg and udder health in relation to a transition from tie-stalls to loose housing systems are also dealt with. Effects of electric cow-trainers on common clinical diseases, reproductive performance and risk of culling were studied by comparing lactation records from Swedish cow-trainer herds with historical and contemporary control records in herds without cow-trainers. Exposure to cow-trainers increased the incidence risk of silent heat, clinical mastitis and ketosis, and changed silent heat from being a neutral disease with respect to culling to a major risk factor. The cow-trainers increased the general negative effect of diseases on the cows’ reproductive performance and risk of culling. The influence of a rubber slat flooring system for tie-stalls on animal behaviour, cleanliness and foot health was studied in a controlled trial during two housing periods in an experimental dairy herd. In half of the stalls, the rearmost part of the solid flooring was replaced with nine rubber-coated 53 mm wide slats, divided by 29-mm slots. Stalls with rubber slats were equipped with ethyl-vinyl-acetate mats in the front part and littered with small amounts of wood shavings daily, while stalls with a solid floor had standard rubber mats and received large amounts of chopped straw daily as bedding. Cows on the rubber slatted floor lay down more easily than those on the solid floor, and rose normally and without any increased risk of slipping. However, there was some evidence of a preference for a solid floor when lying. Cows on the rubber slatted floor were much less dirty on their hindparts than those on the solid floor, and at hoof trimming, the prevalence of hygiene-related foot lesions in hind feet was several times lower in the rubber slat system. In order to study the effects of changes in housing system on foot/leg and udder health, retrospectively collected monthly herd records from Swedish dairy herds were utilized. Significant increases in the incidence of veterinary-treated foot and leg disorders were found up to 18 months after changing from tie-stalls to cubicles and the incidences of clinical mastitis and teat injuries were decreased beyond 18 months after changing from tie-stalls to cubicles or straw yards. Later than 18 months after rebuilding, herds that shifted from long-stalls to short-stalls had less foot and leg lesions than those remaining in long-stalls.