Evaluation of sow and litter performance with addition of a bio-surfactant to lactation diets

Sow performance in lactation is a key driver of productivity in commercial pork production. Lactation diets are formulated with high energy [>14 MJ digestible energy (DE)/kg)] and high fat (>8%) components in an attempt to meet the nutritional demands of lactation. Improved utilisation of the ingested energy may assist in improving milk production, minimising body condition loss and maximising subsequent reproductive performance (Whitney 2012). The emulsification process that assists in the digestion of dietary fat may be improved with the inclusion of a natural bio-surfactant such as Lysoforte^® (Kemin; Killara NSW). This study tested the hypothesis that the inclusion of Lysoforte^® in high fat (6.6% added fat) lactation diets would improve litter weaning weight and help maintain the body condition of sows between farrowing and weaning.

A total of 281 mixed parity sows [Large White x Landrace, PrimeGro™ Genetics, average parity 2.7 ± 0.07 (mean ± SE)] was selected at 15 weeks of gestation and allocated by parity and P2 backfat to one of two dietary treatments: control lactation diet (14.0 MJ digestible energy (DE)/kg, 6.6% added fat and 8.7 g standardised ileal digestible lysine/kg); and control lactation diet plus 0.1% Lysoforte^®. All animals were fed a common pre-farrowing diet at 2.5 kg/d from entry to farrowing. After farrowing, sows were fed the allocated treatment diet on a step-up program for 4 days and then were fed ad libitum. Sow feed intake was recorded daily. Sow liveweight (LW) and P2 backfat were measured on entry to the farrowing house and the day of weaning (26.6 ± 0.15 days of lactation). Litter weight and size were recorded after cross fostering and again at weaning. The impacts of dietary treatment and parity were tested using two-way ANOVA with the sow (litter) as the experimental unit (Genstat, 15th Edition; UK).

Inclusion of Lysoforte^® did not improve piglet weaning weight with treatments A and B averaging 7.57 kg and 7.44 kg, respectively (P = 0.73), nor was there a difference in the number of piglets weaned (P = 0.60). Piglet average daily gain (ADG) increased as sow parity increased (P < 0.001). However the effect of treatment on ADG tended to be variable between parities (P = 0.087). Parity had a significant influence on the P2 backfat response to dietary treatment (P = 0.033), with parity 1 and 2 sows displaying reduced P2 backfat loss with Lysoforte^® inclusion (Fig. 1A). There was no difference between treatments in P2 backfat loss over all parities (P = 0.68). Sows offered the Lysoforte^® diet tended to have a reduced loss in LW from entry to weaning (P = 0.077) (Fig. 1B) however, the interaction between treatment and parity was not significant (P = 0.51). Average daily feed intake for sows offered Lysoforte^® was higher than the controls (P = 0.037), and there was no interaction between treatment and parity (P = 0.40).

Fig. 1.  The effect of Lysoforte^® () fed during lactation vs a control diet () on the change in sow P2 backfat loss (A) and LW (B).

Lysoforte^® inclusion in diets for lactating sows had an effect on the maintenance of sow body condition, particularly in parity 1 sows whose change in P2 backfat loss differed by 3.8 mm between treatments. There was no difference between treatments in wean to oestrus interval (P = 0.91). The outcomes from this study suggest Lysoforte^® inclusion in lactation diets may increase voluntary feed intake and minimise body condition loss in younger parity sows with minimal effect on piglet weaning weights.