Feeding level over the first 30 days of gestation and its consequences on sows' body reserve repletion and litters' characteristics at birth: first results

Six batches of 24 sows each, were used to compare two feeding plans during gestation that differed by the partition of feed supply. From weaning to the 30th day of gestation (G30), feed allowance to sows from BAS treatment BAS (n=38) represented 1.4 times the maintenance requirement (M). Those from HAUT treatment (n=38) were fed 1.7 × M. Corresponding feed supplies to gilts expected to be inseminated were 2.7 and 3.3 kg/d. Total feed supply over 114 days was the same for both treatments.Therefore HAUT sows received less feed from G30 onwards. At farrowing, neither body weight (260 kg on average for both treatments), nor backfat thickness (BAS: 19.4, HAUT: 19.1 mm, P>0.10), nor litter size (BAS: 13.9, HAUT: 14.2 total born, P>0.10) were significantly influenced by the feeding plan. Heterogeneity within litter was not modified but average birth weight was significantly lower in HAUT treatment (1.45±0.34 vs. 1.56±0.33 kg/piglet in BAS treatment). Thereafter litter size at weaning tended to be smaller in treatment HAUT. In conclusion, body reserve repletion and prolificacy did not differ among feeding plans. In contrast, smaller new-born piglets were obtained from over-fed dams during the 1st month of gestation that probably resulted more from inadequate feed supplies after G30 than excess before G30.