Address Digital Dermatitis in young stock before turning out.
Digital Dermatitis in dairy heifers is on the increase. I have seen a number of herds with a significant level of affected cattle. Digital Dermatitis will have long lasting implications for dairy heifers affecting hoof structure and balance, herd longevity, production (Losinger, 2006) and fertility.
Hoof confirmation in replacement heifers is seriously altered by DD. Gomez etal. (2014) showed increased heel horn erosion, heel height, claw length and cleft depth with the accumulation of tissue debris. Hoof conformation can be restored by early detection, clinical cure and functional trimming.
For those herds that graze young stock the window of opportunity to treat these animals effectively is narrowing as turnout approaches. Turning young stock out to pasture reduces some of the main risk factors associated with DD. These include stocking rate, poor hygiene and damage to the integrity of the skin necessary for infection (Speijers etal., 2013)
Turning these animals out without treating them will not be beneficial, mainly because once turned out to pasture it is unlikely that they will be brought back in for treatment. I strongly recommend that a belt and braces approach is implemented for these animals prior to turnout.
Firstly, it is essential that infected animals in a group are identified and treated with a topical treatment. This should include lifting the feet for a few days in succession, cleaning the hoof and treating. I do not recommend applying bandages. These animals should be segregated simply to make it easier to treat the animals routinely.
Secondly, I recommend foot bathing the heifer groups daily up until turnout. A combination of 5% copper sulphate weekly or 2% copper sulphate for 4 consecutive dates, and a disinfectant such as paracetic acid on the other days. Daily sanitation of the hoof is extremely effective at reducing the bacterial challenge. Treatment with copper sulphate is the most effective treatment for DD (Speijers etal., 2010).
Thirdly, ensure that all passage ways and bedded areas are kept as clean as possible. Environment is an important risk factor associated with the incidence of DD (Somers etal., 2005) If you are housing on straw yards I recommend cleaning the yards out and liming the floor before re-bedding. Animals hosed in straw yards are at higher risk of DD (Rodriguez-Lainz, etal 1999).
Finally, it is definitely worth increasing the supplemental levels of vitamin E and Zinc from now until turnout and consider including in winter diets as this will improve skin integrity, boost the immune system and help to reduce the incidence of DD in heifers (Dr Dana Tomlinson).
Remember to record the worst offenders and inspect in the autumn when the heifers are housed. Addressing the problem now will ensure that the hoof confirmation and long term performance of your future herd members is not compromised.