PSIV-10 - Economic analysis of gilts bred with or without heat-not-serve and the impact on gilts longevity to parity three

Abstract: The objective of this study was to determine a heat-no-service (HNS) impact on total born piglets to parity three and the economic implication on the production system. Sixteen thousand six hundred and forty-three gilts were utilized from a commercial production system. Gilts were sorted by having exhibited signs of estrus or not before breeding and the season first service occurred, with farm used as a random effect. Data were analyzed using PROC GLM to form a regression tested for linear, quadratic, cubic, and quartic effects of service age. A linear effect was observed between service age and estrus (P< 0.001) on total born from first service to parity three. Gilts that exhibited an estrus and were bred on the second estrus or later were observed to have greater total number born (38 pigs vs 32 pigs) to parity three compared to gilts bred on their first estrus. The model predicted the difference in total born through three parities is approximately 6 when gilts are breed on the second estrus or later. An economic model was also developed from the regression to determine marginal potential profit for gilts from entering the facility in the gilt development unit to the end of parity three. This model was compared against the actual data to compare predicted to actual data differences. Also, gilts bred on the second or later estrus had a greater percentage of animals with positive profit for the model (81%) and actual (77%) data compared to the gilts bred on the first estrus model (56%) and actual (72%). Profit through parity 3 was predicted to be $31 greater compared to actual $41 greater profit for gilts with a HNS vs gilts bred on their first heat. The differences in profit for gilts bred on the second or later estrus is related to less production days in the gilt farm to reach parity three and increased number of piglets to parity three and greater retention rates. Further research is needed with large production data sets to develop production and economic models for producers and management to aid in solving on farm issues and increase production efficiencies.