|Kanaan, V - PURDUE UNIVERSITY|
|LAY, JR., DONALD|
|Richert, B - PURDUE UNIVERSITY|
|Garner, J - PURDUE UNIVERSITY|
|Pajor, E - PURDUE UNIVERSITY|
Submitted to: Applied Animal Behaviour Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 6, 2007
Publication Date: April 1, 2008
Citation: Kanaan, V.T., Lay Jr, D.C., Richert, B.T., Garner, J.P., Pajor, E.A. 2008. A note on the effects of co-mingling piglet litters on pre-weaning growth, injuries and responses to beavioural tests. Applied Animal Behaviour Science. Volumbe 110, Issues 3-4, April 2008. p. 386-391. Interpretive Summary: An animal’s early environment is fundamental to its development and long term welfare. In particular, the manner in which animals are raised often affects their ability to cope with a variety of stressors later in life, influencing their welfare and productivity. Therefore, investigating the role of early environment on production and welfare problems allows us to identify the causes of these problems, and to develop preventive management strategies. From this study we concluded that co-mingling did not negatively affect piglets’ weight gain and suckling behavior. The occurrence of ear injuries was greater in co-mingled piglets immediately after co-mingling, but these differences were minimized by day 18. Co-mingling did not affect piglets’ response to the isolation test and the backtest. Co-mingling had an effect on piglet’s social behavior, as demonstrated by the responses to the social challenge. Our results suggest that co-mingling litters has an exclusive effect on the development of piglets’ social skills, by primarily decreasing aggressive actions. Additional research is required to understand how co-mingling affects various aspects of piglets’ coping abilities both before and after weaning. These data will aid in the development of management systems to optimize the ability of swine to adapt to group housing.
Technical Abstract: Co-mingling litters prior to weaning alters piglet development and their ability to cope with post-weaning stress. The purpose of this study was to determine how co-mingling litters affected piglets’ growth, ear injuries, suckling behavior and responses to behavioral tests used to measure coping abilities before weaning. Thirty sows and their respective litters were housed in standard farrowing crates until piglets were 12 days old. At 13 days of age, the partition between two neighboring pens was removed for 20 litters allowing piglets to interact (forming 10 co-mingled and 10 control groups). Three focal piglets from each litter were used for data collection. Focal piglets were weighed and the presence or absence of ear injuries was recorded on days 2, 4, 9, 12, 15 and 18 after birth. There were no differences in piglets’ weight gain before or after co-mingling. Injury scores were more abundant in co-mingled litters on day 15 (P < 0.05) but these differences disappeared by day 18. Suckling behavior was recorded on days 5, 8, 10, 14, 16 and 18 after birth. There was no difference in teat fidelity, suckling frequency and mother fidelity between treatments. Three behavioral tests; social challenge, isolation test, and backtest, were performed before and after co-mingling. There were no treatment effects on piglets’ response to the isolation test and backtest. Co-mingling had a significant effect on piglets’ response to the social challenge. Co-mingled piglets showed a longer latency for the first aggressive interaction (P < 0.05), spent more time in proximity to one another (P < 0.05) and performed less single bites (P < 0.05) than control piglets. In addition, the duration and frequency of aggressive interactions (P < 0.05) was lower in co-mingled piglets than control piglets. Co-mingling did not affect the frequency of single head thrusts, escape attempts, or oral-nasal contact during the social challenge. Our results suggest that co-mingling litters during lactation affects the development of piglets’ social behavior, as indicated by responses to social challenge, without detrimental effects on growth, suckling behavior and responses to the backtest or the isolation test.