THE ECONOMICS OF CONTROLLING INFECTIOUS DISEASES ON DAIRY FARMS

Cost effective disease control on the dairy farm can enhance productivity and subsequently profitability. Previous economic studies on animal disease have focused on production losses and evaluation of disease eradication programs and provided little guidance as to the optimal prevention action. This paper presents a theoretical model on the economics of livestock disease and develops an empirical model to determine the optimal set of control strategies for four production limiting cattle diseases: bovine viral diarrhea (BVD), enzootic bovine leukosis (EBL), Johne's Disease (JD) and neosporosis. Control functions indicating the prevalence of infection with each of the four diseases for each of the ten strategies are estimated. The optimal strategies that minimize total disease cost (direct production losses and control expenditures) are provided for each disease on the basis of farm survey results from the Maritime provinces. The results emphasize the importance of introduction checks before new animals enter the herd and adequate vaccination protection as cost-effective control strategies.Farm Management, Livestock Production/Industries,

Assessment of farmers' compliance in implementing recommended cow comfort changes and their effects on lying time, stall and cow cleanliness within smallholder dairy farms in Kenya

Our study aimed to evaluate farmers' compliance in implementing recommendations of farm-specific cow comfort changes, and the effects of these changes on lying time, stall cleanliness and cow cleanliness using a randomized controlled trial carried out on 100 smallholder dairy farms in Kenya, with 62 and 11 farms remaining in the intervention and control groups, respectively. On the first farm visit, data loggers were attached on lactating cows to determine lying time and questionnaires utilized to collect baseline data. Three days later, stall design and management recommendations were given to the intervention group of farmers orally and in written form. After an average of 39 ± 7 days, data loggers were re-attached, compliance was assessed, and a post-intervention questionnaire was administered to the intervention group on the third visit. Three days subsequent to the first and third visits, data loggers were removed from all cows. Data were analysed in Stata 14.2® using proportion tests and Kruskal-Wallis rank tests to compare cleanliness scores and lying time, respectively. Interaction effects between treatment groups and visits were assessed using multivariable mixed linear and logistic regression models. While 46 of the 62 intervention farmers (74%) made at least one recommended change to cow comfort, 63% of the 324 overall recommendations were implemented. The odds of a recommendation being implemented were significantly higher when:1) major recommendations were given relative to minor recommendations (OR = 6.28); 2) recommendations were related to floor characteristics (floor softness and flatness) in comparison to recommendations related to stall design (OR = 3.14). The odds of compliance were lower on: 1) farms where the farm-hands received the recommendations compared to farms that had the female principal farmer receive the recommendations (OR = 0.01); 2) farms that had recommended changes related to roof, alley and sharps fixes relative to stall design fixes (OR = 0.13). Post-intervention, stall, udder and upper hind-leg cleanliness scores improved significantly (p < 0.0001, p = 0.021 and p = 0.017, respectively) in the intervention farms but not in the control farms. There was no significant difference in lying times between intervention and control farms, with 0.6 and 0.2 h/day increases being recorded in the intervention and control groups, from the 10.9 and 10.4 h/day at baseline, respectively. Giving farm-specific cow comfort recommendations to smallholder dairy farmers in Kenya, and providing them with a participatory role in the formulation and implementation of improvement recommendations ensured good acceptance and a high degree of implementation, and led to a subsequent improvement in cow comfort and cleanliness

Promoting Evidence-based Veterinary Medicine through the online resource ‘EBVM Learning’: User feedback

‘EBVM Learning’ is a freely available resource created in 2015 by an international team with the support of RCVS Knowledge. The resource comprises a series of online modules teaching the fundamental concepts of evidence-based veterinary medicine (EBVM) (Ask, Acquire, Appraise, Apply & Assess) supported by case studies, exercises, worked examples and quizzes. The aim of the current study (undertaken in 2019) was to review ‘EBVM Learning’ to ensure its ongoing relevance and usefulness to the range of learners engaged in EBVM. Feedback was gathered from stakeholder groups using website statistics and feedback forms, a survey and semi-structured interviews to provide a combination of quantitative and qualitative data.Website statistics revealed an international audience and a steady increase in visitors exceeding 1,000 per month in August 2020. Feedback via the online form (n=35) and survey (n=71) indicated that the resource was well structured, with an appropriate level and amount of content, useful examples and quizzes and the majority of respondents would use it again. Semi-structured interviews of educators (n=5) and veterinarians (n=8) identified three themes: features of the ‘EBVM Learning’ resource (strengths, suggestions for improvement), embedding the resource in education (undergraduate, postgraduate) and promoting EBVM (challenges, motivation for engagement). At a project team workshop the results were used to plan updates to the existing content and to identify new ways to promote learning and engagement. An updated version of ‘EBVM Learning’ was developed.‘EBVM Learning’ is helping to produce the next generation of evidence-based practitioners and enabling to engage in the concepts of EBVM as part of their clinical practice

Association between milk urea nitrogen and first service conception in smallholder dairy farms under heat and humidity stress

Aim: The study was to evaluate the relationship between the first service conception (FSC) and milk urea nitrogen (MUN) in smallholder dairy farms under heat and humidity stress. Materials and Methods: Dairy cows from 43 dairy farms giving birth between November 2014 and April 2015 (n=295) contributed to the study. All cows were sampled monthly to measure milk compositions, and we collected additional farm data from farmers through a questionnaire. The first service during the first 120 days of lactation was the outcome of interest in this study. Multivariable logistic regression determined significant associations with FSC. Results: The overall FSC was 22% and the mean MUN concentration was 11.55 mg/dl. The final FSC model included MUN concentration, the season of breeding, and protein energy ratio (PE ratio) in the diet. The odds of FSC were reduced by approximately 10% for each mg/dl higher MUN on the day of the milk sample that was nearest to the artificial insemination (AI) day. The odds of FSC were nearly 3 times higher when the first insemination occurred in winter compared to summer first services. Taking into account the nutritional factors, the odds of FSC were nearly 70% higher with an increase in PE ratio of 10 g of crude protein/Mcal from the mean of 35.90 g. Conclusion: This study of smallholder dairy farmers in the hot and humid climate of Thailand confirmed that season, nutritional management, and MUN concentration were associated with FSC. MUN appears to be a useful indicator to monitor the effects of diet on reproductive performance from this study

Bovine Practitioner 36 2 86 91 Stillwater, USA: American Association of Bovine Practitioners.

To determine the effect of subclinical infection with bovine leukaemia virus (BLV), Mycobacterium avium subspecies paratuberculosis (MAP) and Neospora caninum (NC) on milk production in dairy cattle in 3 Maritime Canadian provinces, 90 dairy herds (all on monthly milk recording) were randomly recruited. Within each herd, a serum sample was obtained from approximately 30 randomly selected lactating animals. Samples were tested for antibodies against the agents using commercially available enzyme linked immunosorbent assays (ELISA). Associations were tested between 305-day milk production and test results for each pathogen using linear regression and controlling for sampling weights, within-herd clustering, provincial stratification, lactation number, and linear score somatic cell count. Overall, 20.8, 2.6, and 20.3% of cattle were test-positive for exposure to BLV, MAP, and NC, respectively. MAP test positive cows had significantly lower 305-day milk production than MAP test negative cows, when data were pooled for all lactations, and specifically for lactations one (1260 lb; 573 kg) and five (3020 lb; 1373 kg). There was a negative trend toward lower 305-day milk production for MAP test positive cows in lactation 2 and 4 compared with MAP test negative cows. In lactation 3, MAP test positive cows had significantly higher 305-day milk production (3248 lb; 1476 kg) than MAP test negative cows. No significant differences in production were observed for NC or BLV positive animals. Being test positive for one pathogen was not associated with being test positive for the other pathogens, and no interactive effects on 305-day milk production among pathogen test results were observed.

THE ECONOMICS OF CONTROLLING INFECTIOUS DISEASES ON DAIRY FARMS

Cost effective disease control on the dairy farm can enhance productivity and subsequently profitability. Previous economic studies on animal disease have focused on production losses and evaluation of disease eradication programs and provided little guidance as to the optimal prevention action. This paper presents a theoretical model on the economics of livestock disease and develops an empirical model to determine the optimal set of control strategies for four production limiting cattle diseases: bovine viral diarrhea (BVD), enzootic bovine leukosis (EBL), Johne's Disease (JD) and neosporosis. Control functions indicating the prevalence of infection with each of the four diseases for each of the ten strategies are estimated. The optimal strategies that minimize total disease cost (direct production losses and control expenditures) are provided for each disease on the basis of farm survey results from the Maritime provinces. The results emphasize the importance of introduction checks before new animals enter the herd and adequate vaccination protection as cost-effective control strategies