Preventing Lameness in dairy cows and broilers

Lameness causes behavioural restriction, pain and reduces longevity of farm production animals. It leads to financial loss and is a major welfare concern in animal husbandry as a large number of animals are affected. Studies indicate that on European dairy farms up to 55 out of 100 cows may suffer from lameness and 10–30 % of broilers undergo painful leg disorders. Lameness is a multifactorial problem. In dairy cows, an important cause for locomotory problems are the hard concrete floors in loose housing systems. In broilers, lameness is mainly due to increased growth rate as a result of constant genetic selection and improved diet. Fast growth rate places abnormally high loads on relatively immature bones and joints and causes skeletal abnormalities.

Important tools for detecting and managing locomotory problems in dairy cattle are locomotion
scoring systems. Researchers of the Welfare Quality® project at the University of Kassel (Germany) and University of Natural Resources and Applied Life Sciences (Austria) assessed the inter-observer reliability of one of such systems, which comprised five levels of gait scores. Results from four observers, three of whom were inexperienced, were rather unsatisfactory for gait assessment in non-lame cows. Merging to four or two scores highly improved reliability and led to acceptable results, even at the relatively low training-level of three observers. The assessment of the relative importance of different risk factors in causing lameness in cattle is ongoing. Such information supports the work by the University of Bristol, i.e. the construction of a lameness control programme that addresses the range of lameness problems known to vary between individual herds.
New floors may promote good locomotory health in dairy cattle. The Animal Sciences Group of Wageningen UR (The Netherlands) evaluated different floors: a conventional concrete slatted floor (SC) and floors of profiled solid cement (GC), slatted rubber (SR) or solid rubber (FR). In weeks 0, 6, 12, 18 and 24 the cows' gaits were assessed with a pressure distribution plate (RsScan International, Olen, Belgium, sampling rate of 175 Hz, sensor sizes of 0.5 x 0.76 mm). An even distribution of load across the different legs was assumed to mirror fluid locomotion. Distributions were derived from ratios of values from different legs, with similar measuring values for 2 legs resulting in outcomes approaching 0. The ratio of maximal pressures between the legs was relatively high in SC cows. Cumulative claw surface during a step increased over time for SC cows. Visual evaluation of loading patterns during steps suggest different claw–floor interactions for the different floors. On rubber floors a distinct weight-bearing wall seemed to develop in time, meaning that load was allocated to the strongest claw areas. The claws of the cows on the SC floor were significantly harder than the claws of the cows on the other floors. Claw growth and wear were the highest on the SC floor and this may explain the increased hardness. Behavioural observations suggest that, in comparison to cows on concrete floors, cows on rubber floors spend more time standing and eating and less time standing in cubicles. Slatted floors and rubber surfaces seem to have qualities that promote good locomotory health in dairy cattle.
Reducing broilers’ early growth rate or increasing their locomotory activity, e.g. by specific (sequential) feeding schedules, may in part prevent leg disorders. The Welfare Quality® researchers of INRA (France) exposed male meat-type chickens to one of three different feeding regimes from day 10 to day 24. Controls received a standard diet (100% lysine content) each day, the '100/70’ group was fed 100% lysine one day and 70% the next, while the '130/70' group received 130% lysine one day and 70% the next. The percentages of birds with abnormal gaits at slaughter age were 48%, 16% and 22% for the control, '100/70’ and '130/70’ groups, respectively. These findings suggest that such sequential feeding might be an effective way of reducing the incidence of leg problems. Research by the University of Bristol showed that gait scoring methods could be learned by inspectors from widely different geographical and social backgrounds. This, together with the great similarities in the way broilers are farmed, implies that results could be compared across countries once the inspectors’ performance had been validated during training and at scoring.

Bonne Beerda
Leader Work Package 3.4 Lameness

More information: bonne.beerda@wur.nl