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 of Canadian Cattlemen magazine 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 of Canadian Cattlemen magazine 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 of Canadian Cattlemen magazine 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 of Canadian Cattlemen magazine 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
Respiratory and enteric diseases are the most common and costly diseases in beef cattle. Both of these types of diseases are multi-factorial disease complexes meaning they involve several viruses and bacteria.Currently these diseases are diagnosed using single pathogen tests making the process very inefficient because each pathogen involved requires a separate test. Effective control of these diseases can benefit from a rapid and cost effective diagnostic test where all relevant pathogens can be tested for in a single assay.
Research currently underway and funded by the National Check-off and Canada’s Beef Science Cluster is working to develop two Continue reading
It won’t be long before it’s time to wean calves so that cows can head into winter in good body condition. The abrupt separation of calves from their dams is the most common approach to weaning, but it’s also the most stressful, and calves that experience a lot of stress underperform.
It’s easy to see why weaning is stressful on calves; sudden deprivation of milk and social contact with mothers, being handled for vaccinations, changes to feed and water sources, and transportation to a different environment with unfamiliar pen mates is a lot for young animals to cope with. The stress calves experience through weaning depresses their immune systems, making freshly weaned calves the most susceptible to bovine respiratory disease (BRD) infections. Stressed calves also have lower feed intakes. Listening to their bawling, seeing them pace in their pens and dealing with sick calves is no doubt stressful on producers too.
This article outlines some ideas to keep stress at a minimum during weaning. Understanding the principle of low-stress weaning allows producers to wean calves in whatever ways work best on their operation while enjoying the benefits of reduced incidence of disease in calves, reduced costs and time spent on treatments, better weight gain, and a quieter barnyard. Continue reading
The word ‘footrot’ is often mistakenly used to refer to many types of lameness in cattle. Footrot is a bacterial infection between the two claws of the foot. It is typically caused by the Fusobacterium necrophorum bacterium, which invades damaged or injured feet. Because footrot is a bacterial infection to the fleshy part of the foot, this type of lameness can be treated with antibiotics.
There are several different types of lameness, many of which cannot be treated with antibiotics. Whenever possible, producers should closely inspect the feet to determine the type of lameness in order to choose the appropriate treatment. An improper diagnosis can lead to unnecessary administration of antimicrobials, prolonged discomfort to the animal and increasing loss of production. If a lame animal does not improve with antibiotics, it does not have footrot.
The latest video in the Beef Research School series features Continue reading
This is a guest post written by Karin Schmid, Beef Production Specialist with the Alberta Beef Producers, in collaboration with Reynold Bergen, BCRC Science Director.
In the previous post, we talked about methods to reduce weaning stress in calves. In this article, we’ll highlight the economic benefits of doing so.
Making weaning a low stress event should always be the goal, whether the calves will stay at home for breeding or feeding, go through internet, satellite or auction mart sales, or head directly to a backgrounding or finishing feedlot. Minimizing stress makes for happy calves, spouses and neighbors, and likely has economic benefits as well, especially for those who sell ’reputation’ cattle or retain ownership. High levels of stress or sickness can negatively impact the profits of producers who retain an ownership stake in their calves past weaning. Continue reading
This is a guest post written by Karin Schmid, Beef Production Specialist with the Alberta Beef Producers.
It’s approaching quickly, that time of year when you start to think about weaning your calves. Calves are weaned to make sure that cows can recover their body condition after raising a calf all summer, and to allow for specialized feeding of those calves. All producers do it, but not everyone approaches weaning in the same way.
The most common method of weaning is the abrupt separation of calves from their dams. This method is arguably the most stressful event of a young calf’s life. Not only are the calves abruptly deprived of a ready source of milk, but also social contact with their dams. Then add vaccinations, dietary changes, and transportation to a different environment, with unfamiliar animals, and it’s easy to see why weaning is stressful on calves. Stress depresses the immune system, which makes freshly weaned calves the most susceptible to bovine respiratory disease (BRD) infections.
Alternative weaning methods exist, if you are willing to spend a little more time on the process. Continue reading