Diagnostic laboratories play important role in livestock agriculture

Many of us have changed how we meet with people during the COVID-19 pandemic, and the veterinary community is no exception.

Many summer conferences that veterinarians normally attend to keep up on the latest updates in their field are being cancelled or in some cases transitioned to online meetings.

Recently, I was involved in a short video meeting organized by Dr. Eugene Janzen at the University of Calgary’s School of Veterinary Medicine. Janzen brought together a small group of practising veterinarians, including new graduates, students and experienced practitioners along with some veterinary pathologists to discuss different herd outbreaks that had occurred this past spring in cow-calf herds.

The veterinarians from private practices that worked through these outbreaks presented the cases and did a great job of showing how they worked through them. It was a small enough group that we could discuss the cases and ask questions and although we didn’t have all the answers, it was a great learning experience.

I was particularly struck by the huge benefit, as well as the necessity, of having diagnostic laboratory capabilities available and especially the importance of ensuring that diagnostic testing is affordable so that producers and veterinarians can take advantage of these tools.

We are very fortunate to have some excellent veterinary diagnostic laboratories in Western Canada with specialized veterinary expertise in fields such as pathology, toxicology, bacteriology, virology and parasitology to name a few. It was apparent from our discussion of these difficult cases that without the support of the diagnosticians at these laboratories and the various diagnostic tools that they can supply, it can become exceedingly difficult to make a diagnosis in some of these complicated herd outbreaks.

One problem that can arise is that diagnostic testing can become expensive and in a situation where a cow-calf producer is already suffering through a disease outbreak in which cows are aborting or calves are dying, the last thing the producer often wants to do is spend more money on diagnostic tests when they are already dealing with significant economic losses. However, these diagnostic tests are often a necessary part of providing an eventual solution to the problem.

Veterinary diagnostic laboratory services can also provide us with a form of disease surveillance within the livestock industry.

In some cases, new or emerging diseases can be identified through the samples that are submitted by local veterinarians. It was a simple diagnostic submission from a veterinarian in the United Kingdom that resulted in a case report published in 1986 in the Veterinary Record describing an unusual case of neurological disease seen in a dairy cow in England.

The pathologist who wrote this report highlighted a never before seen brain lesion in a cow that looked like scrapie in sheep. This was the first reported diagnosis of BSE in cattle, which highlights the importance of diagnostic laboratory capabilities and submissions from practising veterinarians. We would have a hard time dealing with diseases such as anthrax, tuberculosis, Johne’s disease, Salmonellosis and many others without the diagnostic capabilities of veterinary laboratories.

As part of my duties at the Western College of Veterinary Medicine, I get to help with our disease investigation unit, in which we try to assist local veterinarians in dealing with herd outbreaks through funding provided by the Ministry of Agriculture in Saskatchewan.

Most of our funding is spent on diagnostic support for the local practitioner and producer and although we can’t solve every herd outbreak, we would rarely come up with any diagnosis without the support of our colleagues in the diagnostic laboratories.

Unfortunately, we go to many outbreaks where the mortality of calves may be significant, but relatively few post-mortems have been conducted. Sometimes this is because dead animals are scavenged and material can be hard to come by, but sometimes it is because the expense is perceived as too much by the producer when they have already lost several calves.

It is important to at least get your local veterinarian involved and allow them to perform some post-mortems so they can get a better handle on what may be causing the problem in your herd. A lot can be learned from a simple post-mortem along with some diagnostic support from the laboratory, and an accurate diagnosis allows a treatment or prevention plan to be more easily designed.

We are fortunate to have easy access to diagnostic labs and specialty laboratory expertise here in Western Canada. Although laboratory tests may not always reveal the cause of an outbreak, it is a useful tool to rule out a variety of infectious, toxicological, nutritional or developmental diseases.

A local veterinarian can provide the most effective advice regarding collecting samples and requesting the appropriate diagnostic tests to help with the diagnosis of problems. When we interact with policy makers and those who control government budgets, it is important to emphasize the importance of these laboratories as a part of the infrastructure necessary for livestock agriculture.

About the author


Stories from our other publications