This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in a September 2021 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
The Beef Cattle Research Council (BCRC) projects featured in this column are funded by the Canadian Beef Cattle Check-Off. When the checkoff increased a few years ago, the BCRC’s budget rose from around 15 cents to 67 cents per head marketed. This allowed us to start some new research programs. Now that we’re a few years in I can update you on how they’re going.
One is our “Proof of Concept” program. Research is complicated and costly, so we have independent scientists review each research proposal to make sure it is scientifically sound and likely to achieve its goal before investing your dollars into it. Sometimes the reviewers say, “This is an interesting project, but it’s really costly, and it all hinges on an untested idea. It’d be better if they had some preliminary evidence that this new idea is worth pursuing, before funding a costly, full-scale project.”
In 2018 the BCRC started funding Proof of Concept projects to gather these preliminary results and help decide whether these new ideas are worth scaling up into full-scale research trials. Here’s what two of the first Proof of Concept projects told us.
Not all lameness is caused by foot rot. Getting a proper diagnosis is the key to determining the appropriate treatment and management for any lameness condition. Lameness can affect any type of cattle including feedlot animals, breeding bulls, range cows, or animals confined to a corral. It limits an animal’s interest in eating, drinking, or breeding resulting in lower weight gains and conception rates, making it an animal health and welfare concern, as well as a production and economic issue.
A 2019 study reported that lameness is the leading cause for health treatments in breeding cows and bulls. However, diagnosing lameness isn’t always straightforward as the condition can be caused by multiple inter-related factors. Another recent feedlot study analysed health records from 28 different western Canadian feedlots over a ten-year period to determine common lameness conditions. Overall, lameness was diagnosed in 4.4% of steer and 4.7% of heifer placements. Comparing diagnoses by class of cattle, 4.9% of calves were diagnosed with lameness compared with 4.0% of yearlings. Of the lameness diagnoses, foot rot was most common at 74.5% of lameness cases, followed by joint infections at 16.1%, then lameness with no visible swelling at 6.1%, followed by lameness due to injury 3.1%. Continue reading →
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the October 2020 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
Cattle were ideally created (or evolved) to consume and digest high fiber diets. Whoever (or whatever) was responsible for designing the rumen so elegantly probably should have paid more attention to the respiratory tract.
The design of the bovine respiratory tract makes it easy for BRD bacteria like Mannheimia, Pasteurella, Histophilus and Mycoplasma to move deep into the lung and find places to hide and makes it hard for the animal’s immune system to counterattack them. The bovine lung is so susceptible to infection and damage that it has been used as an “animal model” of chronic obstructive pulmonary disease (COPD) in humans.
This is a problem because cattle need a lot of oxygen. Cattle need nearly three times as much oxygen as a similar-sized horse just to stay awake and lie around. But the horse has nearly three times more lung capacity than the steer. Lung damage is one of the reasons that BRD hits cattle so hard, so fast. Continue reading →
A surprising proportion of producers believe they run a closed herd. The 2017 Western Canadian Cow-Calf Survey requested reasons why certain management practices were not employed on individual operations. Out of the approximately 25% of respondents who did not vaccinate their cows and heifers against reproductive diseases such as IBR and BVD, over half of those reported that their reason for forgoing those vaccinations was because they had a closed herd. Similarly, over 20% of respondents did not vaccinate their calves against respiratory disease (BRD), and 30% of those indicated having a closed herd was their main reason for not vaccinating.
This high rate of mistaken belief in having a closed herd is not just a Canadian phenomenon. A 2019 UK survey of almost 1000 producers indicated that over half of those who stated they ran a closed herd had purchased cattle within the past two years. According to the US Department of Agriculture’s National Animal Health Monitoring System (NAHMS) 2007-08 survey, over 88% of operations with 50 head or more brought new cattle onto their operations in the past three years. Continue reading →
Vaccination is a proven tool for disease prevention. Vaccination recommendations vary by region and by farm as the environment, production, and management practices can increase or decrease the amount of risk cattle are exposed to. Disease exposure occurs in numerous places including community pastures, fence line contact with neighbouring cattle, auction markets, and breeding cattle, such as bulls, purchased from other herds. However, vaccinating breeding females for reproductive disease and calves for respiratory disease are recommended practices across Canada. A vaccination program should be developed in consultation with a veterinarian who can determine which ones are necessary for your area.
In western Canada, one in ten producers surveyed are not vaccinating their cows for infectious bovine rhinotracheitis (IBR) and bovine viral diarrhea virus (BVD) (Waldner et al., 2019) and more than a quarter of producers do not vaccinate cows for other reproductive diseases (Beef Cattle Research Council, 2019). One third of Ontario producers do not vaccinate their cows for BVD and far fewer vaccinate for other reproductive diseases. In Atlantic Canada, 27% of producers reported not administering general vaccinations. This leaves herds vulnerable. Continue reading →
Bovine respiratory disease (BRD) is one of the costliest health issues facing the beef industry today. While a lot of research on BRD has been focused at the feedlot stage, the disease is also the most common cause of death for nursing calves older than three weeks. BRD can impact any producer, including those who retain ownership of their calves to background, feed, or finish cattle.
Research by USDA ARS Meat Animal Research Center that tracked the annual incidence of BRD in pre-weaned calves over a 20-year period found that the annual incidence varied from a low of 3% to a high of 24% with an overall annual average of 11%. On average, the mortality rate of calves suffering from pre-weaning BRD was 13%.
Several large studies have linked BRD to seasonal peaks. Nebraska researchers collected several years of data on 110,000 calves and found two seasonal peaks in the incidence of BRD. One peak occurs from birth through around 20 days of age, and another takes place when calves reach 70 to 100 days of age. Other studies have shown a similar pattern. The most common age group reported as having BRD were calves between one to 4 months of age.
Once calves are affected by BRD, there are both immediate and long-lasting effects on performance. Studies have shown that calves challenged by BRD could weigh up to 36 pounds less at weaning than their healthy herd mates (Wittum and Perino, 1995). Continue reading →
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the October 22, 2018 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
September’s column summarized a Beef Cluster project that evaluated antibiotic use in Western Canadian cow-calf operations. Nearly all cow-calf farms used antibiotics, but very few animals were treated, and most of the antibiotics used were not related to the antibiotics most commonly used in humans. But when it comes to antibiotic use in the beef industry, most of the attention is focused on the feedlot sector.
Until recently, the best Canadian feedlot antibiotic use information came from a small 2006 project (Antimicrobial Resistance in Escherichia coli Recovered from Feedlot Cattle and Associations with Antimicrobial Use, PLoS ONE 10: e0143995). Antibiotic use practices change over time, so a Beef Science Cluster 2 project updated and expanded this knowledge. Continue reading →
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the October 1, 2018 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
Last month’s column discussed how antibiotics are used in Western Canadian cow-calf operations. Respiratory diseases are a common reason for antibiotic treatment in cows, bulls, and calves and diarrhea is a common reason for antibiotic treatment in young calves. Because both respiratory and intestinal infections can involve many different microbes, having a better understanding of what microbes may be causing a particular animal to be sick could allow more appropriate treatment decisions. For example, antibiotics don’t kill viruses, so using antibiotics won’t help an outbreak of scours that is primarily viral in nature. Similarly, some antibiotics are more effective against some bacteria than others, so being able to select the antibiotic that is most appropriate for the bacteria that are involved would be helpful.
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the September 2017 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
Weed seeds and invasive species may be present even in well-managed pastures and rangelands, but it is hard for them to germinate, establish and spread in healthy, competitive forage stands. Stresses like severe drought, overgrazing, heavy traffic or excavation can weaken forage stands and create opportunities for unwanted plants to take root.
Researchers are now studying whether similar principles may apply to animal health and disease processes. For example, calves that were perfectly healthy on the farm can face a serious risk of bovine respiratory disease (BRD) in the feedlot after experiencing the stresses of weaning, commingling, transportation and ration changes. Dr. Trevor Alexander of Agriculture and Agri-Food Canada’s Lethbridge Research Station and collaborators from the University of Calgary are studying bacterial populations (the microbiota) in the respiratory tract of feedlot cattle. They published the results of a small study supported by the Beef Research Cluster earlier this year (The nasopharyngeal microbiota of beef cattle before and after transport to a feedlot; BMC Microbiology 17:70).
What they did: Little is known about what the “normal” respiratory microbiota looks like in cattle, let alone how it changes in response to any given stress. Because exposing calves to multiple stresses at the same time may have produced large, complex, difficult to interpret changes in the microbiota, this team focused on the effects of simply moving cattle from the home farm into the feedlot. They used 14 Angus x Hereford heifer calves (640 lbs) from Continue reading →
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the May 2015 issue ofCanadian Cattlemenmagazine and is reprinted on the BCRC Blog with permission of the publisher.
Ionophores (Rumensin, Bovatec, Posistac) are not medically important because the ionophores approved for use in cattle are not used in human medicine. Other antimicrobials used in livestock are medically important. Concerns around antimicrobial resistance in both human and veterinary medicine have led to increased scrutiny regarding how medically important antimicrobials are used in livestock production. In response, pharmaceutical companies throughout North America are removing production claims (i.e. growth and feed efficiency) from products containing medically important antimicrobials. Some of these products also have health claims, but four Canadian products only have production claims (two Aureo S-700G products, Chlor S-700, and Neo-Terramycin). These products may disappear unless the companies pursue new health-related label claims.
But do medically important antimicrobials really promote growth? Or do they just keep calves healthy, which grow better than sick calves? Alberta Agriculture and Rural Development’s Dr. Kim Stanford led a research project Continue reading →