Cattle Review

02 July 2022
3 mins read
Volume 27 · Issue 4

Abstract

Introduction: In this Cattle Review we consider papers on the effect of lameness on bull fertility, the role of farm management practices on antimicrobial resistance (AMR) and the use of motivational interviewing (MI) in communication with farmers.

Lameness in bulls

Studies suggest that high cortisol resulting from lameness-associated pain decreases testosterone and disrupts spermatogenesis leading to decreased fertility. The objective of a study by Boakari et al (2022) (Theriogenology10.1016/j.theriogenology.2022.03.034) was to investigate the effect of lameness on cortisol and testosterone concentrations and breeding soundness examination of beef bulls. Bulls, 2 years of age or older, that presented for lameness, foot trim, and/or breeding soundness examination were enrolled. Blood samples were collected for cortisol and testosterone evaluation. A complete breeding soundness examination (BSE) was performed on all bulls. Subsequently, a complete lameness examination was performed, and limb/foot lesions recorded. A blinded evaluator used a lameness score of 1–5 to classify each bull as lame (>1) or not-lame (1). A total of 60 bulls were enrolled (34 with a satisfactory BSE and 26 with an unsatisfactory BSE result). Cortisol and testosterone were not different between the unsatisfactory and satisfactory group. The odds of a satisfactory BSE result were 4.40 times higher in not-lame bulls when compared with lame bulls. The authors conclude therefore that lameness is associated with an unsatisfactory BSE result in beef breeding bulls.

Antimicrobial resistance

There is increasing emphasis on the need to reduce antimicrobial use (AMU) on dairy farms to reduce the emergence of resistant bacteria. In addition to AMU, the role of farm management is an area of growing interest and represents an alternative route for possible interventions. The aim of this study by McLaughlin et al (2022) (Preventive Veterinary Medicine10.1016/j.prevetmed.2022.105666) was to evaluate the impact of farm management practices and AMU on resistances of sentinel bacteria in bulk milk. Dairy farms from two, geographically separate locations within the British Isles were recruited as part of two study groups. Farm management data from study group 1 (n=125) and study group 2 (n=16) were collected by means of a face-to-face questionnaire with farmers carried out during farm visits. For study group 2, additional data on AMU were collated from veterinary medicine sales records. Sentinel bacterial species (Enterococcus spp. and Escherichia coli) were isolated from bulk tank milk to monitor antimicrobial susceptibilities by means of minimum inhibitory concentrations (MICs). MIC data for both groups were used to generate an overall ‘score’ for each farm. For both groups, this overall farm mean MIC was used as the outcome variable to evaluate the impact of farm management and AMU. Practices which were found to be of importance with respect to Enterococcus spp. included management of slurry, external entry of livestock to the dairy herd, use of bedding materials and conditioners, cubicle cleaning routines and antibiotic practices, including use of β-lactams and fluoroquinolones. Practices deemed to be of importance for E. coli MICs included cubicle and bedding management practices, teat preparation routines at milking and the milking procedure itself. The authors conclude that a variety of routine farm management practices are associated with MICs of sentinel bacteria in bulk milk. Amendment of these practices offers additional possible routes of intervention, alongside alterations to AMU, to mitigate the emergence and dissemination of AMR on dairy farms.

Motivational interviewing

Whenever we evaluate research and try to apply it on farm, we must recognise that communication has been identified as one constraint for cattle veterinarians to act as proactive health consultants. Motivational interviewing (MI), an evidence-based client-centred communication methodology, may therefore be a useful tool in veterinary herd health management (VHHM). The aim of this exploratory study by Svensson et al (2022) (Preventive Veterinary Medicine10.1016/j.prevetmed.2022.105679) was to investigate associations between training in MI and different measures of performance in VHHM. MI skills of 36 Swedish cattle veterinarians randomly assigned to two groups — MI veterinarians (n=18) who had received 6-months training in MI and control veterinarians (n=18) who were not trained — were assessed. Skills were categorised as untrained, trained–poor, trained–near moderate and trained–moderate. Veterinarians each visited two to six cattle farms for VHHM consultations and revisited the same farms 3- to 6-months later to document implementation of recommendations. Associations between MI training and performance were evaluated as: a) proportion of consultations resulting in written herd health plans; b) proportion of recommended measures fully or partially implemented; c) Likert scores of different estimates of client satisfaction; and d) total time during 6-months allocated to VHHM visits on cattle farms. A pattern of better performance in trained veterinarians with poor or moderate MI skills than in untrained veterinarians was observed in most variables. Clients were highly satisfied with veterinarians’ attitude, competence, and time efficiency. Farms implemented a median of 66.7% of the measures partially or fully. Veterinarians allocated little time to VHHM visits (median: 2.2; interquartile range: 0.65–4.1 h per week of full-time work within cattle). Veterinarians with moderate skills spent 2.14 times more time on VHHM visits than untrained veterinarians. The pattern of numerically higher values in trained veterinarians supported findings from other studies in the same project indicating a positive effect of MI training on VHHM. These observations suggest considerable potential to increase veterinarians’ engagement in VHHM through MI.