Oxidative stress variation and its relationship to genetics and reproductive performance in a commercial swine breeding herd

Abstract

Oxidative stress (OS) has been used to identify an animal’s stress level. Oxidative stress is known as an imbalance at the cellular level where oxidants outweigh the neutralizing capacity of antioxidants. The inherent variation and possible genetic implications of OS have not been thoroughly investigated. To determine the inherent variation overtime, relationships to reproductive performance, and genetic implications to OS in replacement gilts, measures of reactive oxygen species and serum antioxidant capacity of 318 females from a commercial sow farm were assessed at 23-weeks of age (baseline), d-40 of gestation, d-110 of gestation, d-5 lactation, and d-5 postweaning over two parities. Vitamin E, a known antioxidant with implications in many oxidative stress pathways, was also assessed at the baseline sampling. A genome wide association study using the baseline serum antioxidant capacity and vitamin E measures revealed a window of interest containing the monoamine oxidase gene and FUN14 domain containing 1 (FUNDC1) gene which have implications in reactive behavior and mitochondrial efficiency, respectively. Oxidative stress within a parity was different than previous studies where the greatest level of stress occurred at d-40 of gestation and the lowest occurred at d-110 of gestation. The greatest level of stress over time was at the baseline measure, followed by parity 1 and then parity 2 meaning young gilts have the greatest level of stress. Correlations between OS and reproductive performance at different times across parities were weak and inconsistent. To better understand OS and reproductive performance relationships in future studies, control of environmental variables should be implemented to a greater degree than what was capable in the current study. Further research investigating OS variation, its relationship to reproductive performance, and implications in a commercial swine breeding program is warranted.