AK Johnson, A Garcia, LA Karriker and KJ Stalder
Background: Horn quality is vital to reduce the risk of trauma or injury. The pig’s hooves are susceptible to lesions, such as overgrowth, erosion, and cracks. The objectives of this study were to determine lateral toe growth and lesion severity and type when evaluating multi-parity sow hooves that were housed in gestation stalls over one month. Methods and Findings: Thirty sows were obtained from the same farm, in their first to the fifth week of gestation, in good health and with no obvious lameness signs. Sows were selected for inclusion in this study based on parity (parity 1n=10; 158.8 Kg to 204.1 Kg BW; parity 2n=10; 181.4 Kg to 226.8 Kg BW; parity 3n=10; 204.1 Kg to 249.5 Kg BW) and (2) breed (Duroc; n=11; Cross [Duroc*Yorkshire] n=11; Yorkshire n=8). On the first day of the study, each lateral toe was marked using a paint marker at the coronary band and every seven days for the next four weeks, lateral toe growth and lesions were measured on all hooves, whilst sows stood. Hoof lesions on the medial and lateral toes, dew claws and plantar surface were recorded using the FeetFirst guidelines; Zinpro. A new category was created called “any lesion”. This was defined as summing all lesions for a category of interest for example breed. There were no differences in lateral toe growth between lateral toe pairs (p=0.08) for the same sow. There was a difference in lateral toe growth by sow breed, with Yorkshire sows’ lateral toes growing more slowly when compared to Duroc and Crossbred (Duroc × Yorkshire) sows (p<0.0001). There was a difference by sow parity, with parity two sows’ lateral toes growing the fastest, followed by parity one and three (p<0.0001). Regardless of parity and breed, lesion severity was predominantly scored level one (mild) with cracked wall vertical being the most common lesion type. When comparing foot pairs of the same sow, more lesions were observed on the front (61.7%) when compared to rear (46.7%) hooves. Parity two sows had the most lesions on their toes (hooves), and their toes grew more quickly, and thus new toe growth may not be as hard and could become more easily damaged. Conclusions: It is suggested that caretakers carefully examine toe length and lesion presence at weaning for all sows, but particularly for parity two sows. This examination will result in a high-quality sow with sound hoof integrity being returning to the breeding herd. Additionally, working with the swine herd veterinarian can guide caretakers on how to manage longer toes or lesion presence throughout production. It is advised a good quality sow will have better performance, longevity and overall welfare.