In just the last couple of months, while providing bovine respiratory disease information to cattlemen, I was asked questions about use of intranasal vaccines. Because there are several types of these vaccines, and because of producer interest, I’ll try to address the most appropriate uses of these vaccines to prevent disease in cattle herds.

College of Veterinary Medicine of Washington State University
Professor and Director of Veterinary Medicine Extension and FDIU / Washington State University

Immunizing calves begins with the passive transfer of antibodies through the cow’s colostrum. If the cow has been successfully vaccinated, she will provide disease-specific antibodies to the calf in her colostrum based on the vaccines used.

These antibodies are taken up in the intestine of the calf to circulate in the blood but can also be resecreted at the local, mucosal level.

One example is the secretion of maternally derived IgG antibodies into the gut lumen. Another recent example is the secretion of maternally derived IgA antibodies into the respiratory tract of calves.

There are two basic “kinds” of immunity that can be triggered by a disease agent or a vaccine – cell-mediated and humoral immunity. Humoral immunity includes those circulating antibodies in the blood.

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When we give a vaccine under the skin, the reaction is to mobilize immune cells and get them to make antibodies that can circulate in the blood and go to wherever they are needed.

Cell-mediated immunity does not involve antibodies but instead, involves a series of cells, the chemicals they release and their ability to activate other cells to “eat” or destroy the pathogen.

The mucosal immune response (think mucous membrane) involves both antibodies (IgA) and the cells involved in cell-mediated immunity.

Mucosal immunity is an important defense against respiratory disease agents because most of these agents enter the calf through this route.

Intranasal vaccination mimics natural infection through the respiratory route. Many of these vaccines contain a modified-live (modified to not cause disease, however, stimulating immunity) agent (like IBR) that interacts with the cells lining the respiratory tract and replicates there.

The immune cells local to the area are stimulated by the modified agents and provide the immune response at that local level.

Antibodies get secreted onto the surface of the cells. When a pathogen enters, the antibodies and primed cells can attach, attack and prevent replication of the pathogen.

The immune response is “quicker,” meaning the calf has protection within a short period of time after vaccination, sometimes within a couple of days. In addition, a non-specific immune chemical – Interferon – is produced locally and can help with the immune response.

Differentiating intranasal products

Intranasal vaccines have been developed and studied for quite some time. The first ones were for IBR virus (Red Nose or Bovine Herpes Virus-1) and the virus, PI3.

Newer ones have included bovine respiratory syncytial virus (BRSV) and BVD virus. A very new intranasal vaccine contains modified bacteria for the two major bacterial agents of pneumonia (Mannheimia and Pasteurella).

So if we want this quick response, why don’t we use intranasal vaccines all the time? What are the indications for their use? First, not all intranasal vaccines are the same.

The first difference is in what diseases they protect against.

Intranasal vaccines available for cattleTable 1 shows the different brands of cattle intranasal vaccines and what diseases they are labeled for.

Before using any of these intranasal vaccines, the herd owner and his or her veterinarian need to identify the most likely disease risks on the farm or ranch and choose the vaccines right for the job.

Because of the demonstrated problem of maternal antibody (from colostrum) interference with development of a vaccine-induced active calf immune system for IBR, BRSV and Mannheimia or Pasteurella, we know the timing of injectable vaccines is important.

But because intranasal vaccines confer mucosal immunity at the local level, they are considered to be one strategy to get around the maternal antibody interference problem when vaccinating very young calves.

Although the intranasal vaccines may confer immunity for several months, calves will still need to be in the regular herd injectable vaccination program because those vaccines confer a longer duration of immunity.

Use of intranasal vaccines in the cow-calf herd might include young calf immunization to “prime” the immune system for subsequent vaccinations. They might be used at branding, pre-conditioning, at weaning or before shipment.

They also might be used on arrival to a stocker operation or feedlot if the vaccination history is unknown or for other animals considered to be at high risk.

For dairy cattle, these vaccines might be used on arrival to a heifer-rearing facility, at weaning or before moving to group pens.

Although intranasal vaccines do not require injection, they still require adequate restraint. Their use needs to coincide with when calves are processed and they need to fit in with the rest of herd management. The herd owner-operator and his or her veterinarian need to decide if these vaccines fit into the operation and whether they are needed based on disease risks.

Before using any animal health product, read all labels carefully. On the vaccine labels are the storage requirements, when to use safely before slaughter (withdrawal time), directions for use, dosage, as well as the indications for use (at what age and what for).

Spending money wisely on your vaccination program is important but also not wasting the vaccines purchased should receive full consideration.

References omitted due to space but are available upon request. Click here to email an editor.

—Excerpts from Washington State University Veterinary Medicine Extension Ag Animal Health newsletter, Spring 2014