Strategies to improve piglet nutrient access (Figure 1) are needed to enhance piglet survival. Past research shows feeding fat to sows prior to parturition and during lactation improves piglet energy stores, sow colostrum fat percentage, sow milk fat percentage and piglet survival (Pettigrew, 1981). However, many of these past studies were conducted 40-plus years ago. Since then, a multitude of changes has occurred in U.S. swine production. Hence a modern, large scale study to evaluate the impact of sow fat feeding on piglet throughput is perhaps needed.
While a multitude of plant and animal fats have been shown to improve sow performance, some reports suggest fatty acid composition may impact piglet survival. Jean and Chiang (1999) reported sows fed 10% medium chain fatty acids had numerically greater piglet survival than sows fed 10% soybean oil (87 vs. 79%). The authors suggested using medium chain fatty acids to improve piglet survival. Similarly, Azain (1993) reported sows fed 10% medium chained fatty acids had numerically better piglet survival than sows fed 10% soybean oil (90 vs. 81%). Yet both studies contained fewer than 20 sows per treatment, not enough to draw statistically sound conclusions. Therefore, the objective of our current study was to determine if feeding high levels of soybean oil or coconut oil (source of medium chain fatty acids) prior to parturition enhanced piglet survival and subsequent reproduction.
Data was collected on 1,866 sows at a 3,600 sow commercial farm in eastern North Carolina between May to August. Sows were randomly assigned to one of four treatments from day 108 of gestation until farrowing (Control, supplemented with .5 or 1 pounds of soybean oil per day, supplemented with .5 pounds of coconut oil daily). Sows were randomly allocated to treatments based on parity and location within the farrowing room. Oil sources were top dressed daily with 5 pounds of lactation diet. After farrowing, sows had ad libitum access to the lactation diet.
At birth, piglets received a numbered ear tag corresponding to birth litter. Traits recorded included; total number of piglets born, stillborns, crossfosters, number weaned, piglet survival (number weaned ÷ total number born), litter weaning weight, lactation length, whether a sow farrowed a subsequent litter, subsequent total number born, subsequent number born alive, subsequent stillborns, sow caliper score prefarrow, sow caliper score at weaning and sow caliper lactation loss. Summary statistics are shown in Table 1.
Results by diet are shown in Table 2.
Stillborns and stillborn percentage did not differ between dietary treatments. Yet there was a statistical tendency for sows supplemented with soybean oil to have .06 fewer stillborns than control fed sows. Stillborn percentage at this particular sow farm was substantially less than the reported industry average (3.8 vs. ~7.0%).
No differences in piglet survival across dietary treatments were observed. In a review of supplemental fat for peripartal sows, Pettigrew (1981) reported fat feeding was more effective in enhancing piglet survival when survival was less than 80%. Piglet survival in the current study was above 80% (82.9%). Hence, survival rate could be one explanation for supplemental fat not impacting piglet survival in the current study.
In agreement with the current study, dos Santos et al. (2021) and Holen et al. (2022) reported increased fat feeding in gestation and lactation, respectively, did not impact piglet survival. Taken together, recent results do not suggest fat feeding in the peripartal period greatly impacts piglet survival.
Sows supplemented with soybean or coconut oil prefarrow had greater subsequent total number born and tended to have greater subsequent number born alive than control fed sows. Accordingly, sows supplemented with soybean oil tended to have more subsequent total number born and tended to have higher subsequent number born alive than control fed sows. The difference in subsequent number born alive between sows supplemented with soybean oil and control fed sows was .35 piglets.
Assuming a preweaning mortality of 13%, .35 more pigs born alive would equate to .30 more piglets at weaning. Assuming a weaned pig is worth $35, the value of top dressing soy oil prefarrow would be $10.50 per subsequent litter. Assuming soy oil costs $.70 per lb, the return-on-investment would be 4.3:1 for supplementing .5 lb soy oil per day the week before farrowing and 2.1:1 for supplementing 1 lb soy oil per day the week before farrowing.
No differences in body condition loss during lactation were observed between dietary treatments. Given there were no statistical differences between treatments for number weaned, litter weaning weight or body condition loss in lactation, perhaps this suggests that prefarrow oil supplementation had no impact on sow lactation feed intake.
We would like to thank the graduate and undergraduate students that helped with this project: Sabrina Barreto, Carson Gilleland, Liz Jones, Victoria LeGrant, Aoi Nakanishi, Len Russell and Zack Peppmeier. We would also like to thank the North Carolina production system for their continued help and support and the United Soybean Board for funding. Questions can be sent to Mark Knauer via email.
Source: Mark Knauer, who is solely responsible for the information provided, and wholly own the information. Informa Business Media and all its subsidiaries are not responsible for any of the content contained in this information asset.
Azain, M.J. 1993. Effects of adding medium-chain triglycerides to sow diets during late gestation and early lactation on litter performance. J. Anim. Sci. 71(11):3011-3019.
dos Santos, M. C., U. A. Orlando, C. M. Vier, L. M. Almeida, N. Lu, & S. G. Oliveira. 2021. Effects of increasing soybean oil supplementation prior to farrowing on sow and litter performance under commercial conditions. J. Anim. Sci. 99(Suppl. 1):196-197.
Holen, J. P., J. C. Woodworth, M. D. Tokach, R. D. Goodband, J. M. DeRouchey, J. T. Gebhardt, A. DeDecker & X. Martinez. 2022. Evaluation of essential fatty acids in lactating sow diets on sow reproductive performance, colostrum and milk composition, and pre-weaning litter growth and survivability. J. Anim. Sci. 100(Suppl. 2):22-23.
Jean, K.-B., and S.-H. Chiang. 1999. Increased survival of neonatal pigs by supplementing medium-chain triglycerides in late-gestating sow diets. Anim. Feed Sci. Tech. 76:241-250.
Knauer, M. 2020. Genetics of piglet throughput. National Hog Farmer.
Pettigrew, J. E. 1981. Supplemental Dietary Fat for Peripartal Sows: A Review. J. Anim Sci. 53:107-117.