The relationship between veterinary surgeons, their farmer clients and hoof trimmers is set to expand, if communication between the parties is improved. There are several issues to be taken into account. It is a reality that hoof trimmers attend to the feet of many thousands of cows and most veterinary surgeons see only the problem animals. How a problem animal is identified and how it should be handled and treated in the best interests of animal welfare was one of the considerations at the second annual CPD day of the Cattle Hoof Care Standards Board, held at the University of Bristol.
It was sobering to listen to Professor Becky Whay identifying lessons learned from trials. Over 100 cows were reported to farmers as mobility score 2, but only 12 were treated and the median time to treatment was 65 days. In New Zealand, cows with moderate to severe lameness waited over three weeks before treatment, and those with mild lameness waited 70 days. It is established that delays to treatment make the treatment less effective. If the farmer sees a poor response, they are less likely to take action. The message is that early treatment is cost effective and welfare efficient.
It was also sobering to learn that veterinary surgeons involved in studies have been unaware that early treatment was not taking place when they thought it was. Discussions about using non-steroidal anti-inflammatory drugs (NSAIDS) had taken place between the farmer and the vet, but clearly that was not enough to overcome the difficulties of available time and other herd-related pressures that mean actions are delayed. The traditional view that the vet dictates and the farmer acts has to be put aside. For actions to be implemented, the vet needs to listen to the farmer and share their understanding, and establish two-way communication that recognises the expertise of the farmer and the knowledge and experience of the vet.
The role of the hoof trimmer
Also within that mix is the hoof trimmer. It may surprise some that the Cattle Hoof Standards include aspects of treatment. For example: “Lameness must be investigated thoroughly and systematically using detection of heat, pain, swelling, odour, redness, discharge or visible lesions. Lesions causing lameness must be correctly recognised using professional terminology. Lesions causing lameness must be treated whenever possible without breaching the Veterinary Surgeons Act. Treatments must be administered according to protocols found within the farm’s own veterinary herd health plan. Deviations from the protocols should be discussed and agreed with the client and the local vet.
“Providing advice to farmers on antibiotic selection is a veterinary role only. Periodic summaries of lesions found at hoof trimming should be provided for discussion with the client. Regular team meetings should be offered with the local vet and other advisor, either in a response to a deterioration in foot health or in order to proactively manage on-going improvements in foot health. Trimmers form a frontline disease surveillance role and so in instances when unusual lesions occur, or an unusual outbreak is seen, alarms should be raised. The advice of a veterinary surgeon should be encouraged at the earliest opportunity.”
To be included on the hoof care register, members agree to a spot assessment. Currently the assessments are carried out by a veterinary surgeon (Nick Bell). The member offers a weekly diary of appointments in advance. The audit takes place unannounced part-way through the appointment and involves examining cows that have been trimmed and observing trimming taking place. The trimmer receives verbal feedback on the day and a written feedback report within two weeks.
The cost of the assessment for the member is £275 and it takes place on a farm where they regularly work, using their own kit. The Standards Board has evolved from the National Association of Cattle Foot Trimmers where members pay £150 for an assessment every other year by an experienced hoof trimmer on a farm that may be unknown to the member, where two cows are trimmed. The NACFT member may lose working time and have to travel to the assessment farm.
There has been considerable anxiety about accepting veterinary assessment and the two organisations operate in parallel. The choice of a trimmer to look after hoof health is an important one for the farmer. For dairy herds, the milk buyers are including hoof management outcomes within their criteria for milk purchase, with particular emphasis on mobility scoring. Some trimmers also carry out mobility scoring, but this is a different skill and there are many variations in who provides this service and how.
Factors contributing to hoof health
The CPD day at Langford involved veterinary surgeons, hoof trimmers and other interested parties. Roger Blowey was very frank about changes in understanding about lameness issues and how subsequent research and awareness had altered his perceptions. He stated that “lameness is a disease of cows that starts in heifers”. There are many questions still unanswered and Roger has shown spiky pedal bones at other meetings, but establishing the normal still remains an area for research.
If bony overgrowth has occurred, can it be corrected or do the lesions remain throughout life? Clearly the cause of the “overgrowth” is a major aspect for clarification but the damage caused by internal pressure on the sole is a consideration. Sole ulcers appear to be associated with internal swelling of the hoof which compresses the corium and causes further disruption of horn formation. Boiling up feet and measuring the bones in normal cows has shown that the dorsal wall varied from 52 to 79 mm and toe to heel from 63 to 101 mm. The audience was asked “Is it logical to trim all cows’ feet to the same length?”
George Oikonomou (University of Liverpool) explained that although some dairy herds show a 30 percent average for mobility scores 2 and 3 in cows, the herd variation is from 5 to 55 percent. Studies at different stages of lactation have shown that where bruising occurs at 40 to 50 days post calving, ulcers can be expected by 100 days. It is very important to collect information from individuals about their experiences.
As foot trimmers are seeing many cows, early lactation checks with hoof modelling rather than trimming would provide useful information. The fat pad is thinner after calving with a risk of inflammation. In the first 30 days after calving, a cow is 7.7 times more likely to develop claw horn disruptive lesions than later in lactation. Genomic heritability has been shown for sole ulcers, interdigital hyperplasia, digital dermatitis and digital cushion thickness at calving. Ongoing work with digital dermatitis and treponemes is indicating that initial changes in the skin microbiota may allow colonisation. Opportunistic anaerobic pathogens are implicated with the advice that a clean and dry environment helps to prevent anaerobe multiplication.
Jonathan Huxtable (Zinpro Corporation) outlined the relationship between nutrition and how it predisposes cows to lameness. It is recognised that lame cows have a huge impact on herd performance including milk production, fertility, profitability and feed efficiency. The trace minerals zinc, copper and manganese are involved with bone development, as well as skin and hoof integrity. However, when formulation of rations has gone wrong, there has not necessarily been an increase in lameness cases, although production has been reduced.
This may be one reason why nutritionists and consultants have not always considered lameness when formulating rations and feeding regimes. Roger Blowey highlighted that 85 percent of cattle lameness occurs in the foot, that 85 percent of all lameness is in the hind feet and that 85 percent of all hind foot lameness is in the lateral claw. He asked “Do we have diets that can specifically influence the outer claw of hind feet?”
This educational day arranged by the Cattle Hoof Care Standards Board highlighted the need for greater communication between the various professionals involved with dairy herds, and that new awareness and understanding about lameness is ongoing. Veterinary practices are encouraged to recognise the development of standards and to work more closely with hoof trimmers and farmers to achieve improvements in cow welfare.
