Feeding level during the last week of gestation can influence performance of sows and their litters in the subsequent lactation

This study investigated the impact of feeding level during the last week of gestation on performance of sows and their litters in the subsequent lactation. A total of 48 sows were assigned to one of six feeding levels (1.8, 2.4, 3.1, 3.7, 4.3, or 5.0 kg/d) from day 108 of gestation until farrowing. Post-farrowing, all sows were fed similarly during lactation with a gradual increase in feed allowance in accordance with Danish recommendation until it reached the maximum allowance of 9 kg/d on day 17 of lactation. Plasma samples were collected from the sows during farrowing and lactation, and sow's body weight and backfat thickness, and milk samples were taken during lactation. Litters were standardized to have 13 to 15 piglets each and weighed once weekly during lactation. Plasma concentrations of urea, acetate, and butyrate in sows linearly increased (P < 0.001), while non-esterified fatty acids linearly decreased (P < 0.001) during farrowing with increasing feeding level. Moreover, concentrations of triglycerides (P < 0.001), acetate (P = 0.007), and succinate (P < 0.001) were greater in plasma collected at the onset of farrowing compared to the end of farrowing. Conversely, concentrations of glucose, urea, and butyrate (P < 0.001) were lower in plasma collected at the onset of farrowing than at the end. Sows fed 2.4 and 3.1 kg/d exhibited greater triglyceride concentrations than those fed 3.7 (P = 0.03) and 5.0 (P = 0.02) kg/d. Sows fed 1.8 kg/d during the last week of gestation had lower milk yield in wk 1 (P < 0.001) and wk 2 (P = 0.001) of lactation compared to the other groups. Additionally, litter weight gain (P = 0.04) and litter weaning weight (P = 0.007) were lower in sows fed 1.8 kg/d compared to the other groups. The greatest milk yield, litter growth, and litter size were observed in sows fed 3.7 kg/d during the last week of gestation, whereas the estimate generated by the regression model revealed that sows should have been provided with 4.0 to 4.1 kg/d as an adequate feeding level to maximize these performances in the subsequent lactation. Interestingly, feeding level during the last week of gestation did not influence feed intake during lactation. In conclusion, this study highlights the significance of adequate feed supply (4.0 to 4.1 kg/d) during the last week of gestation in order to maximize performance of sows in the subsequent lactation.Feeding sows at high or ad libitum level during an extended gestation period has been found to have a negative impact on the subsequent lactation performance. Conversely, in some European countries, it has been a common practice to reduce the feed allowance during the last 2 to 3 d before expected farrowing to mitigate issues like constipation and postpartum health problems such as mastitis, metritis, and agalactia. However, recent studies suggest that sows should be fed approximately 4 kg/d during transition period to improve farrowing performance. In the present study, we investigated the carry-over effects of feeding level (dose–response design) during the last week of gestation on lactation performance of sows and their litters in the subsequent lactation. The findings revealed that a lower feeding level during the last week of gestation reduced milk yield and litter size at weaning. Milk yield, litter growth, and litter size at weaning were greater in sows supplied with 3.7 kg/d during the last week of gestation. However, the estimate generated by the regression model indicates that sows should be provided with 4.0 to 4.1 kg/d during the final week of gestation to enhance their performance in the subsequent lactation. Therefore, the present results emphasize the benefits of maintaining an adequate feeding level during the last week of gestation to improve sows’ lactation performance in the subsequent lactation.