Many studies have demonstrated that lameness reduces milk production. Examples are summarized in the table below.
|Country||Description of production loss||Reference|
|France||440 kg for early lactation; 270 for mid- to late-lactation lameness||Coulon et al., 1996|
|Finland||1.5 - 2.8 kg/day two weeks after diagnosis||Rajala-Schultz et al., 1999|
|USA||1.5 kg/day two weeks after diagnosis||Warnick et al., 2001|
|UK||up to 2 kg/day for up to 5 months before and after diagnosis||Green et al., 2002|
Although lameness may be caused by skeletal injuries, pain due to various hoof lesions is by far the most common cause. But which hoof lesions are associated with the greatest milk losses? UK researchers compared the effects of specific hoof lesions on milk loss over complete lactations of 1,824 cows (34.9% lame with at least 1 hoof lesion) in 30 dairy herds.
Monthly test day milk yields of cows with hoof lesions were compared with yields of their herdmates that were unaffected by lesions, from 5 months before until 5 months after lesion detection and treatment. Cattle that developed sole ulcer (SU) and white line disease (WLD) had higher milk production than their unaffected herdmates in the 5 months before lesions were diagnosed. After diagnosis, their milk production fell below the average of the unaffected cows. The estimated lactation milk loss attributable to SU and WLD was approximately 570 and 370 kg, respectively.
In cattle that developed digital dermatitis (DD) there was no significant difference in milk yield compared with unaffected herdmates before or after diagnosis but DD cows did produce more milk after they were treated.
The full research report that was the source of this article is here.