Effect of Sodium Butyrate Protected with Medium Chain Fatty Acids or Bacillus Licheniformis on Behavior of Weaned Piglets Oral Challenged with Etec K88

This study evaluated the effect of sodium butyrate protected with sodium salts of distilled coconut fatty acids (DICOSAN PLUS®; Norel S.A) or Bacillus licheniformis CECT4536 on behavior patterns of piglets at weaning when challenged with enterotoxigenic Escherichia coli (ETEC) K88. A total of 66 piglets of 3 weeks of age were divided in 22 pens (3 animals/pen) and 3 experimental groups: CTR, control group with plain diet (n = 8); DIP, plain diet supplemented with 3 kg/t of DICOSAN PLUS (0.3 % in-feed of 50 % sodium butyrate protected with sodium salts of distilled coconut fatty acids) (n = 8); and PRO, plain diet supplemented with 1 kg/t of B. licheniformis (10⁶ cfu/g) (n = 6). After one week of adaptation, animals were orally inoculated with ETEC K88 (1x10⁹ cfu). Scan sampling was used to evaluate animal behavior during the day before the challenge and two days post-inoculation (2 and 3 PI). Behavior measures were recorded during the morning and afternoon (0800 – 1000 h and 1600 – 1800 h). Use of the space (feeder, heat-light and drinker), active behaviors (exploration, feeding, drinking, walking and others) and inactive behaviors (lying ventrally or laterally, with or without pen mates contact) were registered. Before inoculation, animals treated with DIP and PRO spent more time in the feeder area (P = 0.04) compared to CTR and showed higher frequencies of active behaviors such feeding (P < 0.001) and exploring (P < 0.01), especially during the morning. On day 2 PI, sickness behaviors associated to the digestive disorder appeared such huddling under the heat-light (P < 0.001) and inactive behaviors (P < 0.01). On day 3 PI during the morning, DIP and PRO animals took up the behaviors associated to feed consuming (P = 0.15) and exploring (P = 0.38), with higher presence in feeder area (P = 0.01). The supplementation with sodium butyrate with sodium salts of distilled coconut fatty acids or Bacillus licheniformis in feed improved the welfare of the piglets during the first week after weaning. However, after the challenge with ETEC K88, these treatments could not totally compensate for the impact of the pathogen.