Piglets crushing rate related to sow foot lesions in the farrowing room

Abstract

The aim of this paper was to identify front and rear feet diseases of sows and its relation with the piglets crushing rate, in the farrowing crate. The trial was performed in two piggeries, with 200 sows examined per farm A and farm B. The ratio primiparous (P) / multiparous (M) sows was respected for both farms (65%). Visual feet disease assessment was performed on the day the sows were moved from the gestation unit to the farrowing room. The protocol was based on the Welfare Quality Protocol, where a feet lesion is defined as a sow unable to use one or more limbs in a normal manner, varying in severity from reduced ability to bear weight, to total recumbency. The lesion score was assessed by trained veterinarians on sows front and rear feet. Five claw parameters were scored: heel overgrowth and erosion (HOE), toes overgrowth (length of toes, TO), overgrowth or length of dew claws (DC) mainly on the rear limbs, where the accessories hooves grow in a more consistent way, horizontal and vertical wall cracks (CWH, CWV) and white line cracks (WL). Lesions scores were assessed according to a modified protocol by Deen et al. (2008), the Feet First method, stopping the maximum front score to 5, and for rear to 10. Each of the four feet was scored from one to 5, with score 1 meaning no lesion and score 5 (10 for rear feet) meaning a severe lesion. The sum of the score of the four claws was called the ‘total score’ (up to 20). At the end of the trial, since feet disease with score higher than 6 were rarely detected, the statistical analysis was performed on front/rear score up to 5. The predominant type of wound, either on hind legs or on rear legs was, in both farms, heel overgrowth and erosion (HOE) followed by toes overgrowth (TO). The number of born alive, mummified and stillborn, crushed, alive after 3 days, dead before weaning and number of weaned piglets were recorded. Results highlighted that front lesions values were higher in the Farm A (0.73 vs 0.47 for M sows and 0.55 vs 0.26 for P sows, P<0.05). Score on rear limbs was affected by parity (P<0.001), higher values were detected in multiparous sows, as it was expected. Sows in Farm A, where gestation room had a concrete partly slatted floor, crushed more piglets per litter then sows of Farm B, with gestation rooms equipped with a concrete slatted floor, in the considered 3 d period (+ 0.3 for M sows and + 0.23 for P sows, P<0.001) and showed higher values for front feet disease (P<0.05). The higher crushing rate determined by front lesions could be explained by the difficulty of the sow in lifting and turning to the rest position, this assumption needs further investigations, in larger scale, on the mechanics of movements exhibited by sows in farrowing crates equipped with different floors.