Incidence of lameness and abrasions in piglets in identical farrowing pens with four different types of floor

BACKGROUND: Lameness in piglets is a major animal welfare issue. Floor abrasiveness is a common cause of superficial injury in piglets in farrowing pens. The abrasion achieved may act as a gate for infections, which in turn may induce development of infectious arthritis. In this study, the influence of improvements of the floor quality and of increased ratios of straw in identical farrowing pens was measured. METHODS: The study was carried out at a herd with four identical farrowing units with solid concrete floor bedded with 1 kg chopped straw per sow and 1 hg per piglet and day. Nothing was changed in the management of the four identical farrowing units, but four experimental groups were created: Group I – control, Group II – the amount of bedding was doubled. The surface of the floor was repaired in two units, Group III – Piglet Floor(®), Flowcrete Sweden AB, Perstorp, Sweden and Group IV – Thorocrete SL(®), Växa Halland, Sweden. Three farrowing batches were studies in each unit. In total, 93 litters (1,073 piglets) were examined for foot and skin lesions until the age of 3 weeks. The occurrence of lameness was registered until weaning at an average age of 4.5 weeks. Twenty seven lame piglets were culled instead of medicinally treated and subjected to necropsy including histopathological and microbiological examinations. Isolates of streptococci, staphylococci and E. coli were tested with respect to antimicrobial resistance. RESULTS: Piglet born on the repaired floors had the lowest prevalences of abrasions at carpus. Also the doubled straw ration decreased the abrasions. Skin lesions at carpus decreased significantly in magnitude in all four systems from day 10. At day 3, the sole bruising scores of the control unit were greater than the other three units (p < 0.001). At day 10 and 17, sole bruising was less common in the units with repaired floors than in the control group and the group with doubled straw ration. In total 41 piglets were diagnosed as lame, corresponding to 3.8% of all live-born piglets (n = 1,073). Around 85% of these diagnoses took place during the first 3 weeks of life and the risk incidence of lameness decreased from 1.5% during the first week of life to 0.5% during the fourth week. The incidence of lameness was highest in the control unit and lowest in the units with repaired floors. Twenty lame piglets were confirmed to have bacterial growth in the joint. The causative agents were Streptococcus dysgalactiae subsp. equisimilis (60%), Staphylococcus hyicus subsp. hyicus (35%) and Escherichia coli (5%). These isolates were sensitive to all antibiotics included in the antimicrobial panels. CONCLUSION: The results suggest that proper maintenance of the floor can prevent the degree of roughness and abrasiveness of the floors, which in turn can contribute significantly to prevention of abrasions, sole bruising and lameness in piglets. Maintaining the surface of concrete floors with two different commercially available solutions both decreased the incidence of abrasions and sole bruisings and thereby also of arthritis significantly. Also doubling the amount of chopped straw turned out to prevent development of skin lesions and sole bruisings to some extent, and subsequently also the incidence of arthritis.