Dairy cows change locomotion score and sensitivity to pain with trimming and infectious or non-infectious lesions

Lameness can negatively affect production, but there is still controversy about the perception of pain in dairy cows. This study aimed to verify the effects of hoof affections in dairy cows on locomotion score, physiological attributes, pressure nociceptive threshold, and thermographic variables, as well as assess improvement on these variables after corrective trimming and treatment. Thirty-four lame lactating cows were gait-scored, and all cows with locomotion score ≥4 were retained for this study 1 day before trimming. Lame cows were diagnosed, pressure nociceptive threshold at sound, and affected hooves were measured, thermographic images were recorded, and physiological attributes were evaluated. Hooves with lesions were trimmed and treated and cows were re-evaluated 1 week after such procedures. The experimental design was a completely randomized design. Each cow was considered an experimental unit and traits were analyzed using paired t test, linear correlation, and linear regression. Digital and interdigital dermatitis were classified as infectious diseases while laminitis sequels, sole ulcers, and white line were classified as non-infectious diseases. After 1 week, the locomotion score was reduced on average in 1.5 points. Trimming increased the pressure nociceptive threshold for cows with non-infectious affections while tended to increase the pressure nociceptive threshold for cows with infectious affections. Physiological attributes and thermographic values did not change with trimming. Trimming and treatment have benefic effects on animal welfare as gait is improved and sensitivity to pain is reduced.