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High lactose pellets fed from 4 days of age convey lifetime benefits when compared to a standard pre-weaning diet
An experiment was conducted to assess the lifetime response and carcass characteristics of feeding a high lactose complex diet (HL) versus a standard commercial diet (C) from 4 days of age until weaning. The litter performance of piglets from day four of age was measured using a total of 32 sows with 16 litters per dietary treatment. At weaning the median 240 pigs (120 per trt) were selected from the total pool of 370 and 5 unisex pigs were penned together according to treatment (n = 24 per trt). Pen weights were equalised and variance within pen minimised. All pens were fed and managed the same way from wean to slaughter to ensure any difference in lifetime performance was due to pre-weaning treatment only. Pigs were first taken for slaughter at week 20 (139 d) with slaughter weight, age and treatment recorded individually. All remaining pigs were slaughtered the following week 21 (146 d). Analysis of variance was used to determine treatment effects with repeated measures analysis undertaken to assess the effect of time upon results. There were no performance differences pre-weaning. In the nursery phase HL piglets had a higher DLWG during days 0-7, 7-14 and 0-28 compared with C piglets (P=0.007, P=0.039 and P=0.030 respectively). Over the whole 36 day nursery phase the HL piglets grew at 31 g/d more than the C piglets reaching a BW difference of + 1.05 kg P= 0.007). During the grower-finisher phase HL pigs remained significantly heavier compared with the C fed pigs with HL pigs being +2.58kg heavier at week 20 (104.25 vs 101.67kg; P=0.019). HL pigs tended to have heavier slaughter weights compared with the C pigs (107.8 kg vs 105.6 kg respectively; P = 0.052). This tendency of the HL pigs to be heavier became a significant increase in both hot (81.45kg vs 79.31kg P=0.001) and cold carcass (79.83kg vs 77.72kg P=0.001) weights due to an increased killing out% (75.69% vs 75.14% P=0.003). Backfat and estimated lean meat % were not affected by treatment. Analysis on a number of samples collected during this study at various slaughter points are being conducted to help elucidate the mode of action responsible for the increase in lifetime performance from feeding a HL diet pre-weaning.
Keywords: creep diet, lactose, lifetime performance