Identifying Early-Life Behavior to Predict Mothering Ability in Swine Utilizing NUtrack System

SIMPLE SUMMARY: Improving sow productivity and welfare have been long-withstanding goals for the swine industry. Identifying novel traits and phenotypes to accomplish these objectives is needed. The objective of the current study was to determine if activity-based phenotypes collected by the NUtrack livestock monitoring system, NUtrack, could serve as early-life indicator traits for mothering ability in swine. The phenotypes collected included distance traveled, average velocity, angle rotated, time allocated to eating, lying lateral, lying sternal, standing, and sitting. The response variables selected in first parity females to model mothering ability were gestation length, number born alive, and number weaned. Simple linear regression models were generated to analyze the relationship between activity traits and reproductive measures. The results of this study indicate that select activity traits may be used to explain a portion of the variability in gilt reproductive performance. This information is foundational to informing future selection decisions pertaining to the use of activity traits in breeding programs. ABSTRACT: Early indicator traits for swine reproduction and longevity support economical selection decision-making. Activity is a key variable impacting a sow’s herd life and productivity. Early-life activities could contribute to farrowing traits including gestation length (GL), number born alive (NBA), and number weaned (NW). Beginning at 20 weeks of age, 480 gilts were video recorded for 7 consecutive days and processed using the NUtrack system. Activity traits included angle rotated (radians), average speed (m/s), distance traveled (m), time spent eating (s), lying lateral (s), lying sternal (s), standing (s), and sitting (s). Final daily activity values were averaged across the period under cameras. Parity one data were collected for all gilts considered. Data were analyzed using linear regression models (R version 4.0.2). GL was significantly impacted by angle rotated (p = 0.03), average speed (p = 0.07), distance traveled (p = 0.05), time spent lying lateral (p = 0.003), and lying sternal (0.02). NBA was significantly impacted by time spent lying lateral (p = 0.01), lying sternal (p = 0.07), and time spent sitting (p = 0.08). NW was significantly impacted by time spent eating (p = 0.09), time spent lying lateral (p = 0.04), and time spent sitting (p = 0.007). This analysis suggests early-life gilt activities are associated with sow productivity traits of importance. Further examination of the link between behaviors compiled utilizing NUtrack and reproductive traits is necessitated to further isolate behavioral differences for potential use in selection decisions.