Efficacy of Bacillus subtilis and Bacillus licheniformis (BioPlus2B®) on sow lactation performance, litter growth, nursery performance and health of pigs challenged with PRRS virus post-wean

Probiotics have been shown to support normal growth and immune function in pigs in challenging environments. A commercial probiotic (BioPlus2B®) containing two microbial species (Bacillus subtilis and Bacillus licheniformis) was tested to determine its effect on lactation of sows, pre-weaning performance of litters, and post-weaning performance of pigs challenged with PRRS virus. Sows (n = 120) were fed to meet or exceed NRC 2018 requirements and divided into two treatment groups: control and BioPlus2B®. BioPlus2B® was fed daily at an equivalent of 1.6 x 109CFU/kg and daily feed intake was recorded. Production practices were closely monitored in order to reduce the risk of bacteria cross-contamination between treatment groups and to maintain responsible animal welfare practices. By 24 hours post-farrow, piglets were cross-fostered within treatment group and subsequently weighed. They were weighed again on day 17. Upon weaning at approximately 21 days, piglets from each treatment group were separated into one of three BSL2 rooms and allocated to one of 36 pens per treatment for a 28-day growth study. The treatment group was fed BioPlus2B® daily at 1.1 x 109CFU/kg. At seven days post-wean, pigs were infected IM with 2 x 103.5 TCID 50 of the PRRS virus. Sow, litter, or pen was considered the experimental unit except for birth and wean weights. Sows that consumed BioPlus2B® daily birthed heavier piglets, consumed more feed throughout lactation, and tended to wean heavier pigs than Control sows. Pigs that consumed BioPlus2B® post-wean resulted in greater ADG, ADG:ADFI, and reduced mortality after PRRS infection. Data is expressed as least square means ±SEM. Values at P< 0.05 are considered significantly different while values between 0.05< P