Investigating tools to assist dairy farmers in identifying the causes of lameness in dairy cows

Abstract

Foot lesions causing lameness in dairy cows are a major source of production and economic losses and affect the welfare of dairy cows. The literature suggests that dairy farmers often diagnose and treat lame cows without expert opinion or assistance. Although there is a paucity of research regarding dairy farmers’ ability to diagnose and treat foot lesions, the high culling rates associated with lameness may indicate poor diagnosis or treatment. Therefore, research into tools to assist dairy farmers in identifying the causes of lameness in dairy cows is a priority. The broad aims of this thesis were to: i) conduct a systematic review of tests described in the literature for the detection of lameness and the diagnosis of foot lesions, ii) determine dairy farmer ability to correctly diagnose and treat foot lesions, iii) investigate the potential for simple mobile phone technology to be used as a remote consultation tool between dairy farmers and veterinarians, and iv) investigate the beliefs underlying dairy farmer intentions to improve their management practices of foot lesions causing lameness.The systematic review identified a number of tests for the detection of lameness, foot lesions, sole ulcers and digital dermatitis. No tests were identified for the diagnosis of specific foot lesions. Key objectives of this study were to assess the methodological quality of the included studies, compare the performance of the identified tests using reported sensitivity and specificity values, and subsequently make recommendations regarding suitability for implementation on farm. However, none of the tests reviewed and assessed could be recommended due to incomplete reporting of pertinent information and significant risk of bias in all studies. A key recommendation from this study is that authors of future studies in this field should use the STARD guidelines. This would enable thorough evaluation of future tests.Data were acquired from a previously conducted observational study to determine dairy farmer ability to correctly diagnose and treat foot lesions and to introduce the concept of a tele-foot-health system, where digital images of foot lesions were sent to a remote veterinarian for assessment. Diagnostic agreement was assessed between two sets of raters, an on-site (farm) veterinarian and a dairy farmer and the farm veterinarian and a remote veterinarian, for four criteria: body region, tissue, diagnosis and treatment. Overall, the farm veterinarian and dairy farmer demonstrated weak to almost perfect agreement, whereas the farm veterinarian and remote veterinarian demonstrated moderate to almost perfect agreement. For the farm veterinarian and dairy farmer, weak levels of agreement for diagnosis and treatment suggest that the dairy farmer may need more assistance in diagnosing and treating the foot lesions occurring in their herd. The moderate to almost perfect agreement achieved between the farm veterinarian and remote veterinarian indicates the potential for success of the proposed tele-foot-health system. More research is needed to further investigate and validate its use.The final research chapter used a questionnaire based on a social–psychology framework, the Theory of Planned Behaviour. In brief, such studies identify individuals’ key behavioural, normative and control beliefs in relation to the behaviour of interest and assess the associations between the beliefs and intention to perform the behaviour. This study identified that dairy farmers believed improving their current management practices of foot lesions would improve animal welfare, increase milk production and was worth the cost involved (behavioural beliefs). Dairy farmers indicated that the opinions of consumers, staff, and animal welfare groups were important in their decision to make improvements (normative beliefs). Better equipment and facilities, improved knowledge and training, and a favourable cost benefit ratio were perceived as factors that would enable dairy farmers to improve their management practices (control beliefs). While all of these beliefs may be considered as potential drivers to facilitate positive behavioural change, the behavioural beliefs were identified as the priority beliefs that industry should target in the development of strategies to increase dairy farmer intentions to make improvements to their current management practices of foot lesions.This thesis has demonstrated that dairy farmers need support for diagnosing the foot lesions that affect the dairy cows in their herds. While no tools of this nature currently exist, the tele-foot-health system introduced in this thesis offers a possible solution to assist dairy farmers in both the diagnosis and treatment of foot lesions. However, further research is required to fully support its implementation on the farm. To support the uptake of tools like this, this thesis demonstrates the importance of targeting dairy farmer behavioural beliefs in the development of strategies to promote improved dairy cow foot health. In conclusion, this thesis has provided direction for further research into tools to aid dairy farmers in improving their management of foot lesions causing lameness in their dairy herds.