Long-term feeding with 10% regular rapeseed meal during gestation and lactation on performance of mixed-parities sows and their litters

Four batches of 24 sows each were used to study the effects of either 0 or 10% incorporation of low glucosinolate (GLS) regular rapeseed meal in gestation and lactation diets on prolificacy, lactating performance and reproduction over three successive reproductive cycles. The aim was to update and complete the literature data taking into account the characteristics of the currently available rapeseed meal. The GLS content in rapeseed meal used was 14.5 μmol/g dry matter on average, with a maximum level at 16.3 μmol/g. The sows were allocated to one of the two treatments and fed the experimental diets from weaning onwards. The two diets were isoenergetic and their amino acid contents were similar. During gestation, the GLS intake remained below 5 mmol GLS/d (except for two sows), whereas it averaged 8 mmol/d during lactation (max. 10 mmol/d).Including 10% of commercial rapeseed meal had no negative consequence on sow and piglet performance. Both feed intake, prolificacy at farrowing and performance of sows after weaning were similar among treatments: sows from the rapeseed treatment farrowed 43.6 piglets over three reproductive cycles on average, vs. 44.8 in the control treatment (P>0.10). Similarly, survival and growth rate of piglets until weaning were not were affected. These results are supported by the similar thyroxin plasma levels in sows or piglets among treatments which suggests that GLS intake did not alter thyroid function.