Comparative study between 5% copper sulfate and a beta-ionone and limonene solution in a split footbath
Digital dermatitis (DD) is a major cause of lameness in dairy herds (NAHMS, 2002) often controlled with a copper sulfate footbath. Alternative solutions are being explored as copper retards crop growth and yield when waste footbath solution is applied to fields. An alternative to copper sulfate is a beta-ionone and limonene solution (RotNot, Neogen Corporation, Lexington, KY). The objective of this study was to compare the frequency and severity of DD using a beta-ionone and limonene solution versus copper sulfate. The study was performed on a commercial farm in Kentucky from March 2, 2013 through May 25, 2013 with 91 lactating Holstein cows. Footbath solutions were delivered through the use of a split footbath with a beta-ionone and limonene solution, at a concentration of 1:1000 on the right hooves and 5% copper sulfate on the left hooves. The DD lesions were scored every 3 weeks using the Döpfer scoring system (Döpfer et al., 1997): M0 indicates no lesion; M1 represents an early growth less than 2 cm in size and generally not painful; M2 indicates a growth greater than 2 cm and painful to the touch; M3 represents a growth in the healing stage covered with a scab; and M4 designates a chronic non painful growth. The FREQUENCY procedure of SAS (SAS Institute Inc., Cary, NC) was used to run a chi-square test. The results indicated a significant change in DD frequency from the beginning (29.1%) to the end (52.7%) of the study across treatments (P < 0.01). McNemar’s test statistic indicated that no significant difference existed in the proportions of M1 and M2 lesions between the beginning (21.9%) and end of the study (27.5%) for 5% copper sulfate (P = 0.42). McNemar’s test indicated a significant increase in M1 and M2 lesions with a beta-ionone and limonene solution from the beginning (13.2%) to the end (52.7%) of the study (P < 0.01). These results suggest that copper sulfate was more effective at preventing DD lesions than a beta-ionone and limonene solution. A beta-ionone and limonene solution footbath may not be a viable alternative to 5% copper sulfate footbath for DD lesion prevention.
Keywords: digital dermatitis, copper sulfate, split footbath, hoof care