The Effect of Superdosing Phytase from 109 Days of Gestation through Lactation on Farrowing Duration, Piglet and Sow Performance

Phytases enhance nutritional value of feed by the hydrolysis of phytate, improving mineral, energy, and amino acid utilization. A study was conducted to investigate the effect of superdosing of a modified E. coli phytase (Quantum® Blue) from d 109 of gestation through lactation on farrowing duration, neonatal piglet mortality, and sow and litter performance. Lactation diet was corn-soybean meal based, formulated to meet requirements (3433 kcal of ME/kg, 0.74% Ca, 0.51% total P, 1.00% SID Lys) without phytase (Control,) and with phytase (Treatment,) supplemented at 2500 FTU/kg of diet at the expense of corn. One hundred and seven sows (Landrace X Yorkshire); were blocked by parity and randomly assigned to either T1 (N=52, BW 250.6±2.8 kg; parity 3.80±0.39) or T2 (N=55, BW 250.9±3.2 kg; parity 4.2±0.42). Infrared video cameras (Nuvico Inc., Englewood, NJ) were fitted in the farrowing rooms such that each camera captured 2 focal sows of same parity in adjacent stalls pre-farrow. Cameras were connected to digital video recorders (ED-P1600, Nuvico Corp.) and a monitoring system. A sub-set of 25 sows were monitored on video; 11 sows on Control and 14 sows on phytase. The time difference between the appearance of the first piglets and the expulsion of the placenta was recorded as farrowing duration. Sow body weight (BW) and back fat (BF) thickness were recorded at d 109, 24-hour post-farrow, and at weaning. Piglet performance data were recorded. The count and continuous data were analyzed using Proc Glimmix procedure with Poisson distribution and Proc mixed procedure of SAS, respectively. The model included treatment as fixed effects while each sow was considered random effect and experimental unit. Backfat at d 109 was used as covariate for all backfat evaluations. The PDIFF option was employed to declare significant means, if applicable. Significant differences were declared at P<0.05, while a trend is considered between 0.05>P≤0.10. Least square means, their standard errors and P-values were provided. Phytase supplementation did not influence sow BW, BF, and ADFI from d 109 to weaning (P˃0.05) but reduced the farrowing duration compared to the control (521.5±45.24 min vs 710.4±83.63 min, P<0.046). Addition of superdosing phytase to sow’s diets tended to reduce the number of stillborn piglets (1.26±0.18 vs 1.69±0.23, P=0.08) and numerically reduced piglet pre-weaning mortality by 1.7% units relative to the control sows. In conclusion, superdosing phytase exhibited a potential to reduce neonatal piglet mortality by reducing the farrowing duration.