Non-healing hoof lesions in dairy cows

I AM grateful for the responses to my letter (VR, November 12, 2011, vol 169, p 534) from Owen Atkinson (VR, November 19, 2011, vol 169, pp 561–562) and from Arturo Gomez and others (VR, December 10, 2011, vol 169, p 642). Gomez and others asked ‘how many of these lesions involve digital dermatitis (DD) lesions on the corium and how the authors showed that the lesions were DD lesions’. My response to this question is taken from the paper by Evans and others (2011), where my definition of ‘non-healing’ hoof lesions was given as ‘had a topical granular appearance, were particularly pungent in smell, did not heal well, and in many cases required amputation of the affected claw’. To this definition I would now add ‘a typical moist granular topical appearance’. These lesions were PCR tested for each of the three DD organisms, namely Treponema medium-like, Treponema phagedenis-like and Treponema denticola-like spirochaetes, and ‘. . . all three BDD treponeme groups were present in 84.2 per cent, 81.3 per cent and 55.6 per cent of samples of toe necrosis, non-healing white line disease and non-healing sole ulcer …