Abstract Processing piglets within 4 days of age, including tail docking, castration of male piglets, and iron and antibiotic administration, is common practice in the swine industry. However, scrotal ruptures in male piglets because of faulty castration and processing techniques pose an economic impact on swine profitability. There has been limited research evaluating delayed processing and subsequent effects on pre-weaning mortality (PWM) and male scrotal ruptures in pigs. As a result, this retrospective data analysis was conducted to investigate the interactive effects of birth weight and age at processing on PWM and incidence of scrotal ruptures in male piglets. Data analyzed were from a communal set of farrowing room metrics collected on United Animal Health’s 1,000 head (DNA or PIC) research sow farm, which batch farrows 216 sows every 5 weeks. All sows and piglets are uniquely identified with a RFID tag (LeeO). Piglets are individually weighed at birth and weaning, and all procedures or interventions are recorded electronically in the LeeO electronic recording system. A total of 80,358 individual piglet records including birth weight, age at processing, weaning weight, and weaned pig status from February 2022 to January 2025 were included in the dataset. Age at processing ranged from 1 to 11 days and included iron and antibiotic injection, tail docking, and male castration. Birth weights were classified into 0.68 to 2.27 kg in 0.11 kg increments. Pigs were classified as either alive or dead at weaning and, for males, scored on scrotal rupture detection. Data were analyzed with PROC MIXED, using sex, birth weight, age at processing, and all interactions as fixed effects, and sow/litter as a random effect. There was a 3-way interaction (P 0.05) for overall PWM. For females, lower birth weight had increased PWM (P 0.05) compared to heavier birth weight; however, age of processing did not affect PWM. For males, there was an interaction between birth weight and age at processing. As both birth weight and age at processing increased, PWM decreased (e.g., 21.3% for 1.13 kg pig processed at 3 d of age vs. 8.5% for 1.36 kg pig processed at 7 d of age; P 0.05). For incidence of scrotal ruptures in male piglets, as age at processing increased, scrotal ruptures decreased (7.2% for 3 d of age vs. 2.7% for 8 d of age; P 0.05), whereas birth weight did not affect incidence of scrotal ruptures (4.0 – 5.0% across all birth weight categories; P 0.10). The results of this retrospective data analysis confirm previously observed effects of birth weight on pre-weaning mortality and suggest that delaying processing on male piglets, particularly in light birth weight males, may significantly increase piglet survivability through reduced scrotal ruptures.
Puls et al. (Wed,) studied this question.