76 Lactation feed intake and seasonal effects on reproductive performance and downstream impact on lifetime performance

Abstract

Improved genetics in commercial pig production have resulted in larger litter sizes that require increased milk production and increased energy requirements for the sow to raise the litter. Individual sow (n=10,797) data collected from June 2018-December 2023 at United Animal Health’s Research Farms were analyzed to examine potential factors impacting sow and progeny performance. Radio-Frequency Identification (RFID) tags were applied to all pigs, and the LeeO individual animal identification system was used to collect individual sow and piglet data. Research farrowing rooms (216 total farrowing crates) were equipped with computerized feed system which recorded individual daily lactation feed intake and was used to calculate lactation average daily feed intake (ADFI). Sows were ad libitum fed a 1.10% SID Lys commercial lactation diet. During analysis, sows were divided by parity into lactation feed intake levels or season. The objective of this retrospective study was to evaluate the impact of lactation ADFI and seasonal effects on sow and litter performance. Sows with increased lactation ADFI, regardless of parity, weaned heavier pigs (Table 1), that were also heavier at the end of nursery and the sows better maintained BW during lactation (P < 0.001). Post-weaning, a larger percentage of high feed intake females returned to heat by day 5, compared to low feed intake females (P < 0.05). Higher lactation ADFI females had improved conception rates, along with higher total born in subsequent litters (P < 0.05). Parity 1 females weaned during summer months, compared to all other seasons, had lower lactation ADFI (Table 2) and weaned lighter litters (P < 0.001). Compared to all other seasons, when parity 1 females were weaned during summer months, a lower percentage of females returned to heat by day 5 and conception rates had reduced (P < 0.05). Parity 1 females weaned during the summer lost more BW during lactation and had smaller subsequent litters in compared to being weaned in Winter or Fall (P < 0.05). Similar to parity 1 females, parity 2-5 females weaned during summer months had decreased lactation ADFI, weaned lighter litters and lost the most weight during lactation (P < 0.001). These data confirm the importance of strategies to improve sow lactation feed intake, resulting in improved sow reproduction and downstream progeny performance. Seasonal differences play a significant role in U.S. sow herds so implementing management practices that improve lactation feed intake during summer months will help reduce negative seasonal effects.