The Combined Use of Automated Milking System and Sensor Data to Improve Detection of Mild Lameness in Dairy Cattle

Validation of the hind feet position score and its association with heel height difference in dairy cows

Hind feet position scoring (HFPS) categorizes the outward rotation of the hind feet from the line parallel to the midline of the body in standing dairy cows. It has previously been used as an indication of both differences in heel height between the lateral and medial hind claw (to determine the need of hoof trimming) and the presence of claw lesions in sound cattle. In this observational study, the agreement of HFPS with other types of hoof angle measurements, as well as its association with the heel height difference (HHD) between the claws were investigated.A total of 51 dairy cows were assessed independently by three observers in two measuring rounds on two different measuring days each. On each occasion, they scored the HFPS, and measured the angle of outward rotation of both hind feet using a digital protractor (DIG) and a compass app (COMP). Heel height difference was measured only during the second occasion. Intra- and interobserver agreement were calculated using weighted kappa statistics (HFPS) and intraclass correlation (DIG, COMP and HHD). Associations between HFPS and DIG, COMP and HHD were analyzed using linear mixed models.Intra- and interobserver reliability were poor to good for HFPS, DIG, COMP and HHD. HFPS was significantly associated with DIG and COMP but not with HHD. Using the median value of repeated HFPS scores could increase the robustness of the HFPS assessment, as our data indicate that the cows frequently shift the position of their hind claws. Overall, there was a poor correlation between HHD and HFPS, so HFPS may not be determined by HHD alone; future research should consider other reasons for outward rotation of the hind feet.

Hind feet position score: A novel trait to genetically reduce lameness incidence

Lameness is an important health and welfare issue that causes considerable economic losses in dairy herds. The objective of this study was to investigate whether the hind feet position score (HFPS) can be used as an auxiliary trait for genetic evaluation of lameness. The HFPS is evaluated by visual scoring of the position of both the hind-digits to the mid-line of the cow's body. The higher the heel height of the lateral claw, the higher is the HFPS, and the higher is the risk for development of lameness. In total, 3,478 records from 1,064 Fleckvieh cows from 35 farms were obtained between September 1, 2021, and March 5, 2022. Data collection was carried out by the regional milk recording organizations. Hind feet position was scored visually by trained personnel during routine milk performance testing in the milking parlor using a 3-class scoring system: score 1 = 0° to <17° indicating a balanced heel height of both the medial and the lateral claw; score 2 = angle of 17° to 24°; score 3 = angle of >24°. After all cows had been milked, locomotion scoring was performed for each animal using a 5-class scoring system with locomotion scores ranging between 1 (normal) and 5 (severely lame). Using HFPS, sensitivity and specificity were 69.5% and 66.8%, respectively, for detecting lameness defined by locomotion score ≥2. For genetic analyses, a bivariate linear animal model was fitted with fixed effects of herd, parity, lactation stage, and classifier, and random effects of animal and permanent environment. Heritabilities for HFPS and locomotion score were 0.07 and 0.10, respectively, and the genetic correlation between the 2 traits studied was 0.80. These results suggest that the HFPS could be used for genetic evaluations to reduce lameness incidence in dairy cattle.