The Canadian Cow-Calf Surveillance Network

Background

Animal health, welfare, and antimicrobial resistance can have significant impacts on the economic, environmental, and social sustainability of the beef sector. Surveillance provides quantitative evidence that helps to understand how management practices and decisions on our beef operations impact animal health and welfare and helps prioritize checkoff research investments. Understanding the extent to which producers are adopting animal health and welfare management practices informs extension efforts. Animal health monitoring and surveillance programs also provide objective evidence to help producers, veterinarians, industry leaders and other policymakers to manage these risks and support public and consumer confidence as well as international trade of Canadian cattle and beef products.  

The first iteration of the surveillance network was established in the previous cluster (ANH.23.13) and included 100 herds in Alberta, Manitoba and Saskatchewan. Information gathered was focused on animal welfare, marketing, and production practices. ANH.21.17 saw the expansion of this network to garner key Canadian insights. 

Objectives

• Recruit a group of 175 herds that will serve as the network core. These herds and producers will provide a platform that will be able to provide baseline information regarding the national beef cow herd. Baseline information on herd productivity, welfare practices, health, nutrition, and biosecurity will be collected through regular surveys. 
•  Collect biological samples such as serum and fecal samples from the core herds at regular intervals to provide meaningful estimates of various production limiting diseases in these herds. 
• Use the resulting prevalence estimates and production parameters in various economic models or modelling systems to provide stakeholders in the beef industry with baseline information that may affect the productivity and efficiency of cow-calf production. 

What They Did

181 cow-calf herds from across Canada were recruited as a resource for data and samples over 5 years. Criteria for participation was based on a minimum herd size of 40 cows, maintenance of basic production records, as well as a willingness to participate. Two annual surveys were completed by producers every year to evaluate productivity data, one after the end of the calving season and the second after pregnancy checking and weaning. An annual survey was also completed on a specific management topic. These surveys focused on topics such as animal welfare and pain management practices, antimicrobial use, vaccine use, technology adoption and record keeping, and management factors affecting pre-weaning calf mortality. At two time points (fall of 2019 and fall of 2021), samples were collected from a subsample of animals in participating herds to evaluate antimicrobial resistance of fecal bacteria in cows and calves, antimicrobial resistance of nasal bacteria in calves, the presence of production limiting diseases such as bovine leukosis virus, Johne’s disease, bovine viral diarrhea virus and leptospirosis, and trace mineral levels in cows and calves. Data was analyzed from the surveys to provide estimates of productivity and various management practices being carried out in Canadian cow-calf herds.

What They Learned

• Despite the new regulatory changes in antimicrobial sales, antimicrobial use in cow-calf herds in Canada remained relatively unchanged since 2018. Antimicrobials were primarily used for treatment of respiratory disease in calves, neonatal diarrhea and lameness in adults, however most herds treated less than 5% of animals for these reasons. 
• Most of the E. coli isolates recovered from fecal samples were susceptible to all antibiotics. Only 16% of all isolates were resistant to at least one antimicrobial. 
• Copper deficiency is the most common trace mineral deficiency, with 24-43% of Western Canadian and 20% of Eastern Canadian beef cows being deficient in serum copper. Selenium deficiency was less common in Western Canada (<1%) than in Eastern Canada (4.6%). 
• 92% of cows and replacement heifers and 72% of bulls were vaccinated with the core viral vaccines. 92% of producers vaccinated suckling calves with core viral vaccines, but only 47% provided a second dose prior to weaning. Clostridial vaccines are more likely to be used in all classes of cattle in Western Canada compared to Eastern Canada. 
• Individual female records (80%) and feed testing (84%) were commonly reported as currently or occasionally used, followed by on-farm weigh scales (66%). Western herds were likely to utilize feed testing and nutritionists, ionophores and hormone implants, while reproductive technologies were more commonly used in Eastern herds. Large herds (>300 cows) were more likely to adopt technologies that aid in data capture (i.e., weigh scales, RFID scanners) and follow recommended practices (i.e., 63d or less breeding season, feed testing). Paper was the main record keeping format and production records were used for culling and replacement heifer selection. 
• Johne’s disease was present in approximately 1% of beef cows in Canada and estimates of the percentage of positive herds ranged from 5-18% depending on the test used. The fecal PCR test was shown to be much better at detecting positive animals when compared to the blood test. 
• Bovine leukosis virus was identified in 4.9% of cows. Overall, 28% of herds had at least one positive animal. 
• BVD virus was identified in only 0.2% of weaned calves tested or approximately 2 in every 1000 calves. 3% of herds had calves with active BVD infections. 
• Leptospirosis was identified in a small proportion of weaned calves tested. Approximately 1% of calves had been exposed to the grippotyphosa and pomona serovars. 0.4%-0.9% had been exposed to serovars such as hardjo, icterohemmorhagiae and bratislava. 
• Productivity benchmarks from the participating herds (75% of all herd records were below these values):  
  • Non-pregnancy rates – 10% of cows and 14% of heifers 
  •  Abortion rate – 2.2% of cows and 3.1% of heifers.  
  • Death from birth to 24hrs – 3.4% of cows and 6.0% of heifers.  
  •  Calf death from 24hrs to weaning – 5.0% for cows and 8.0% heifers  
  • Calving assistance – 2.3% of cows and 10.8% of heifers with hard pulls 

What It Means

This study provides a broader understanding of actual productivity and disease levels and how they are changing over time in Canadian beef herds. Antimicrobial use was largely unchanged after 2018 regulatory changes in how antimicrobials could be sold were instituted and antimicrobial resistance remains low overall in the cow-calf industry. There are some gaps in management practices that could be improved across the industry including adoption of technology, use of vaccines in certain classes of animals, and especially in trace mineral supplementation (given the large proportion of animals affected with copper deficiency). Johne’s, bovine leukosis virus, bovine viral diarrhea virus and leptospirosis are still at relatively low levels in our herds. In particular, the research on Johne’s disease will be valuable to help veterinarians recommend which tests to recommend when dealing with that disease. Productivity data has provided important benchmarks and demonstrated that herds that calve early and are more intensively managed at calving time tended to have higher losses due to respiratory disease and navel infections. 

The next installment of the C3SN is funded under the Beef Science Cluster IV. Results expected in 2028.