An Investigation of Parturient Ocular Appearance in Sows

Protocols that enable prompt identification of sows in need of assistance during farrowing are important for optimal production outcomes. Change in the colour and appearance of the sclera of the eye can indicate increased stress. This warrants investigation into its use for the identification of sows in need of assistance at the time of parturition. To this end, a three-level ocular scoring system for the pig was devised and subsequently used in a preliminary investigation into the relationship between farrowing kinetics and visual changes in the sclera at farrowing. Data were collected and analysed from twenty randomly selected Large White × Landrace crossbred sows during farrowing. It was determined that sows with a severe ocular score were more likely to experience a prolonged farrowing duration (<i>p</i> = 0.013) and incur increased parturient straining of either total straining time (<i>p</i> = 0.011) or straining per piglet (<i>p</i> = 0.025). There was a significant association between ocular score and litter size (<i>p</i> = 0.043). Ocular score was not associated with sow parity (<i>p</i> = 0.728) and inter-piglet interval (<i>p</i> = 0.075). The proposed three-level scoring system successfully identified sows experiencing an abnormal parturition as defined by a prolonged farrowing duration and increased straining time. Findings from this study suggest the potential application of this simple ocular scoring tool for identifying sows experiencing an abnormal farrowing via in-person application or integration into remote monitoring systems in the future.