Effect of Increasing Feed Allocation or Soluble Fiber Inclusion in Late Gestation on the Performance and Behavior of Late Sows

Abstract A total of 1,479 mixed-parity sows and gilts (1050, PIC) were used to evaluate the effects of increased feed allocation or soluble fiber included in diets fed the last two weeks of gestation on sow performance and behavior. Sows were housed in 28 pens containing 47 to 55 sows per pen. Each pen was equipped with three computerized gestation feeders (Gestal; Jyga Technologies, St-Lambert-de-Lauzon, Quebec, Canada). Pens of sows were blocked in groups to account for date of pen loading and then allotted to one of three treatments with nine or ten replications per treatment. Treatments consisted of 1) control diet (corn-SBM-DDGS-based) fed at 2.49 kg/sow/day; 2) increased allocation of the control diet by 1.13 kg/sow/day; and 3) 2.49 kg/sow/day of control diet plus 1.21 kg/d (3.70 total feed/d) of soybean hulls to provide 100 g/d soluble fiber. Pens contained sows with different breed dates and treatments started when the first sows reached d 104 of gestation. Sows were weighed the day before the start of treatment diets and again when they entered farrowing. Sows were video-taped continuously, and video was analyzed on d 3 and 5 in 6, 2-h timeframes (0100-0300, 0500-0700, 0900-1100, 1300-1500, 1700-1900, and 2100-2300). Aggressive interactions were defined as: 1) sows knocking or pushing pen mates with their head; 2) sows mounting pen mates; or 3) sow forcefully biting ear, face, body, or vulva of pen mates. Sow parity and days exposed to treatments were used as covariates in the model. Time of day was included in the model when analyzing pen behavior. There were no differences in initial BW between treatments (264.2 kg). Increasing feed allocation or soluble fiber increased (P 0.001) ADG compared to the control group. Increased feed allocation resulted in a greater ADFI compared to the fiber treatment, and sows fed increased dietary fiber had greater ADFI compared to control sows (P 0.001). There were no differences in number born alive, stillborn, or weaned between treatments. There was a treatment × time interaction for total aggressive interactions (P 0.001). Although the means did not separate at most timeframes, numerically, feed allocation and fiber inclusion reduced total aggressive interactions at timeframes 0100-0300, 0500-0700, and 0900-1100, but had an inverse effect at timeframe 1700-1900. In conclusion, increasing feed allocation or soluble fiber resulted in greater ADFI, as expected, which translated into an increase in ADG. Fewer total aggression interactions were observed for the high feed allocation and fiber treatments earlier in the day, but increased total aggressive interactions at night, indicating treatment had an impact on behavior and activity within the pen during late gestation.