Distribution of subjectively evaluated conformation traits in commercial growing replacement gilts

• Published in: Journal of animal science 2020-11, Vol.98, p.6-6
• Main Authors: Moeller, Grace A, Abell, Courtney L, Somrack, Tom P, Herring, William O, Holl, Justin W, Stalder, Kenneth J
• Format: Article
• Language: English
• Subjects: Animal breeding; Breeding of animals; Conformation; Farms; Feet; Gestation; Hogs; Housing; Leg; Livestock; Locomotion
• ISSN: 0021-8812; 1525-3163

Feet and leg/locomotor issues represent a primary reason for sow removal from U.S. breeding herds. A shift from gestation stalls (GS) to group-sow housing (GSH) is occurring the U.S. swine industry, emphasizing the importance of structural soundness in replacement gilts. The objectives of this study were 1) to determine if feet and leg/body conformation score differences exist when evaluated at approximately 50 kgs. and 100 kgs.; 2) estimate subjectively scored feet and leg/body conformation trait repeatability within and across measurement time and scorer(s); and 3) determine if the ideal feet and leg conformation traits and scores within traits are the same within GS and GSH. A total of 4494 gilts were evaluated at approximately 22 weeks of age at 3 different farms within the same production system by 4 scorers, representing varying levels of experience. The conformation traits evaluated included locomotion score (LS), front and rear leg conformation (FLC and RLC), front and rear pastern angle (FP and RP), front and rear foot position (FFP and RFP), rib shape (RS), foot size (FS) and toe size (TS). Across farms, the mean gilt BW was 83 ± 11.5 kg. Across scorers and the entire gilt population, the mean conformation scores were: LS (0.06 ± 0.16), FLC (6.1 ± 0.54), RLC (5.4 ± 0.40), FP (3.6 ± 0.62), RP (4.0 ± 0.64), FFP (4.4 ± 0.31), RFP (4.1 ± 0.30), RS (4.3 ± 0.72), FS (2.0 ± 0.35) and TS (4.8 ± 0.61). The entire gilt population was divided amongst four individual sow herds (2 GS and 2 GSH). Sow performance will be followed for three parities to determine the relationship between production and longevity within gestation housing systems and determine if the relationships are associated with one or more conformation traits and/or differences in scores within each conformation trait.