The Effects of Space Allowance and Toy Provision on the Growth, Spatiotemporal Distribution of Behavior, and Pen Cleanliness of Finishing Pigs

Excretion and lying are key behavioral factors that cause pen fouling, thereby affecting pig welfare, pathogen fecal-oral transmission, and air quality in pig housing. This study investigated the effect of space allowance and toy provision on the spatiotemporal distribution of pigs' excreting and lying behavior, as well as the score of floor cleanliness in finishing pig pens. A total of 144 Landrace x Yorkshire x Duroc hybrid fattening pigs were randomly assigned to 12 part-slatted pens at stocking densities of 0.75, 1.05, and 1.35 m(2)/pig with 12 pigs per pen, and 2 pens at each density level were provided with hanging chains and rubber stars as toys. The results showed that for the average daily gain (ADG) of the pigs, the main effect of space allowance was significant (p < 0.05). The ADG at the stocking density level of 1.35 m(2)/pig was significantly higher than 0.75 and 1.05 m(2)/pig (p < 0.05). The ADG of the pigs at a density of 0.75 m(2)/pig in the toys group was significantly higher than the no toys group (p < 0.05). When occupied space was limited, the provision of toys was beneficial to the growth performance of the pigs. Space allowance and toy provision did not affect the time-varying regularity of the pigs but had a certain impact on the areas where the two behaviors occurred. At a density of 1.35 m(2)/pig, the excreting rate in the corner areas of the slatted floor and the lying rate in the middle area of the solid floor were significantly higher than at a density of 0.75 and 1.05 m(2)/pig (p < 0.05). Under the conditions of this study, when the stocking density was 1.35 m(2)/pig and toys were provided, the average daily gain of the pigs was the highest, and the pigs excreted more in the defined excretion area, lay more in the lying area, and the cleanliness of the lying area was also higher. In the case of space constraints, the provision of toys can offset some of the adverse effects of space constraints on pig growth and pen cleanliness.