Performances, milk quality, and piglet growth in lactating sows fed former food products

Due to their nutrient composition, former food products (FFPs) can replace grains in pig diets. Therefore, we hypothesized that including FFPs in a sow’s lactation diet wouldn’t affect their lactation performance. However, the FFPs’ richness in saturated fatty acid (FA) and scarcity in unsaturated FA will impact the FA profile of sow milk. As unsaturated FAs have immunomodulatory effects, one could expect effects on piglet growth. After farrowing, twenty Swiss Large White sows were allocated to either a diet with 25% FFPs (FFP) or a diet with 15% linseed cake (LIN) during lactation (n=10 per group). The two groups were balanced for body weights (BW), backfat thickness (BF), and parity. Litters were standardized to 13 piglets on average. Individual BW and BF of sows were measured at farrowing and at weaning and feed intake was recorded daily. Milk samples were collected on d17 post-partum to evaluate the chemical composition and the immunoglobulin (Ig) content. Piglet individual BW was measured at several time points until 5 weeks post-weaning. Although FFP sows ingested daily less (P< 0.05) feed, BW and BF of FFP and LIN sows at weaning was similar (P> 0.05). The contents (g/kg) of dry matter, protein and fat in milk were or tended to be higher (P< 0.10) while that of lactose was lower (P< 0.001) in the FFP than in the LIN group. The percentage (g/100 g milk FA) of lauric acid was higher (P< 0.001) whereas the percentage of linoleic acid, alpha-linolenic acid, and eicosapentaenoic acid was lower (P< 0.01) in the FFP group compared to the LIN group. The concentrations of milk IgG and IgA were unaffected (P> 0.05) by the diets. The FFP piglets tended (P≤ 0.10) to grow slower in the pre-weaning and overall period and consumed less feed (P< 0.05) from 3 to 5 weeks post-weaning. The inclusion of 25% of FFPs in the lactation diet may be too high as it reduced the daily feed intake, which may have impaired milk yield and ultimately hindered piglet growth.