Vaccinations – An Important Part of Dairy Management

By Heather Smith Thomas

Vaccination is one of the tools that every dairy utilizes to keep animals healthy, to minimize disease problems and use of antibiotics.  Immunization is a necessary aid to limit or prevent disease due to common pathogens, such as Infectious Bovine Rhinotracheitis (IBR) virus, Parainfluenza-3 (PI3) virus, Bovine Viral Diarrhea (BVD) virus, Bovine Respiratory Syncytial Virus (BRSV), clostridial infections, and leptospirosis.  The vaccination program must take into account a variety of factors including infectious disease problems in the immediate area or region.

Maximizing immune response with a good vaccination program raises the threshold for disease challenges, reducing the need for antibiotics and increasing the percentage of young animals that stay healthy the rest of their lives. Which vaccines to use and when to use them may vary from dairy to dairy, depending on location and management practices.  Work with your herd health veterinarian to develop a total herd health program for your particular operation.  

Even though good management and biosecurity measures can greatly minimize disease risk, some diseases can still be a threat. Leptospirosis, for instance can be carried by deer or other wild animals on the farm, or by rodents or canines urinating in haystacks or any carrier animal (even other cattle) urinating in water sources.  Dairy cows or young animals at pasture may be more at risk than those in confinement where there is less interaction with wildlife.

Other diseases are every-present in the environment.  Many clostridial diseases (such as blackleg, redwater, blacks disease, malignant edema, or enterotoxemia due to Clostridium perfringens) are not spread by animal to animal contact but by spores in the environment or even in the animal’s own digestive tract.  They cause disease when conditions are right for the spores to “come to life” and proliferate.  Which diseases to be concerned about will depend somewhat on your location and the risk for transmission.

Rhyannon Moore-Foster, DVM, PhD, Assistant Professor, Livestock Field Service, Colorado State University, has worked with dairies for many years.  “On a dairy, we want to make sure cattle are vaccinated and receive boosters at the right time.  What diseases they are vaccinated for will partly depend on the region and which diseases are most prevalent, and also whether cattle are intermixing with other animals—such as on a heifer growing farm—or never leave their home farm,” she says.

Most people utilize vaccination against respiratory diseases.  “Typically these come in a combination product, covering several viral diseases but also may include bacterial respiratory diseases.  There are many different products available.  Any of the major brands tend to be effective, as long as they have trials to back them up,” she says.

“On a dairy, many people tend to go with products like Bovi-shield or Vira-shield, but these are simply brand preferences; it depends on availability of products and also what your veterinarian might recommend,” says Moore-Foster.

There are two categories—modified-live vaccines and killed vaccines.  Modified-live will typically have two components.  They have a dry pellet or powder in one bottle and a sterile diluent or some other fluid to mix with it, just before you use it.  “You want to make sure you mix both of them together.  Follow label directions because often both components contain an important part of the vaccine.”

Don’t save any left-over fractions once those are mixed together.  The modified live virus only lasts a few hours and even the bacterial components won’t last more than 24 hours, and the vaccine is no longer viable.  If you only have a few animals to vaccinate at the same time, buy the smallest-dose bottle so you don’t have to waste so much when you throw away what’s left.  Mix a new bottle for the new group of animals.

“If you go to the expense and trouble to vaccinate, you want the vaccine to be effective!  Always read the label, to know if that product needs to be boostered in a few weeks.  Typically a modified-live vaccine given to an animal for the first time—such as a replacement heifer– will need at least two doses about 3 to 4 weeks apart.  It will take more than one dose to gain maximum immunity,” she says.

“Some animals may mount a good immune response with one dose but others won’t without a booster.  If the animals are naïve to those vaccines it is very important to give two doses the first time, and after that they will only need an annual booster for the modified-live vaccines,” says Moore-Foster.

“It’s also important to not give pregnant animals a modified-live vaccine unless they’ve had a vaccination prior to becoming pregnant and have some immunity already.  Otherwise it’s best to use a killed vaccine, to eliminate the risk of causing that animal to abort and lose the pregnancy.  The killed vaccine will typically be much safer,” she says.

“The downside of killed vaccines is that they don’t stimulate as great an immune response as the modified-live vaccine, and will need boostered more frequently.”

Some producers give every cow a “scours prevention” vaccine a few weeks ahead of calving, to stimulate production of antibodies that will be included in the colostrum.  A killed vaccine can be given one to two months prior to calving.  In many dairies, cows calve year-round, so each cow should be vaccinated at the proper time.  “This is usually at the time of dry-off or one to two months before calving,” she says.  Then there will be good antibody concentration in colostrum for her calf or for other newborn calves if you save the extra colostrum.  It will keep for a few days in the refrigerator, or you can freeze it for later use.

Vaccines and their timing may vary with each operation.  “We generally think about respiratory diseases and also the pathogens that cause scours in calves.  Sometimes dairies add a salmonella vaccine, and some dairies also give a pinkeye vaccine,” she says.  

Any calves that are not sold soon after birth—especially any dairy heifers kept for replacements–will need clostridial vaccines to protect against blackleg, malignant edema, and Clostridium perfringens (that can cause acute enterotexemia and sudden death in calves).  In some parts of the country the 7 or 8-way clostridial vaccine should also include Clostridium haemolyticum to protect against “redwater” and this vaccination is probably even more important for adult animals than for calves.  It should be boostered every year—and in some locations twice a year.

CALF VACCINATIONS – Young pre-weaned calves usually require minimal vaccination.  They generally don’t respond to immunization for two to three weeks after birth if they received adequate transfer of antibodies from colostrum.  However, an intra-nasal dose of IBR-PI3 vaccine during this time can be justified as a preventative measure against respiratory disease related to those viral agents, according to a University of Oklahoma Extension publication.

At weaning, or two weeks prior to group penning or group housing before weaning, calves should be vaccinated with a modified-live IBR, BVD, PI3, BRSV vaccine and a 7-way clostridial bacterin-toxoid.  Pasteurella spp. (multocida and haemolytica) bacterin-toxoid and Leptospira spp. bacterin may be administered at this time.  You want them to have some immunity before they come into contact with other calves.

 

HEIFER VACCINATION – At 6 to 10 months of age, heifers should be revaccinated with modified live IBR, PI3, BVD, BRSV virus vaccine.  They also need a clostridial product—at minimum a 2-way clostridial vaccine (up to 8-way), and a brucellosis vaccine.  They should have a leptospirosis bacterin (up to 5-way, and at least L. pomona at minimum).  If a history of leptospirosis or clostridial disease exists on the property in calves at a younger age, appropriate earlier vaccination should be done, according to the Oklahoma Extension bulletin.

Dairy animals sometime receive a mastitis vaccine, and if that’s the case, they must not receive any other gram negative vaccines including Pasteurella spp., Salmonella spp., Campylobacter, Haemophilis somnus, E. coli or Moraxella bovis bacterins within five days of the mastitis vaccines.  Giving too many gram-negative products at once can cause serious problem.

FOLLOW LABEL DIRECTIONS – Check labels on all vaccines, not only for directions for proper administration (dosage, injection routes/sites such as intramuscular or subcutaneous).  Most vaccines also have a withdrawal period; the length of time that must elapse before that animal can be slaughtered for meat.  Some of the chemicals and preservatives need to be cleared from the body before the meat is used for human consumption.

There are many different products for respiratory diseases; some are intra-nasal and some are injected.  “The injectable products do a better job at stimulating long-term immunity, but in a herd that is facing an immediate problem, the intra-nasal vaccines can give quicker response,” says Moore-Foster.

CARE AND HANDLING OF VACCINES – All vaccines need to be kept refrigerated and within a certain temperature range, to remain viable for their expected shelf life.  Make sure they stay cool when you bring vaccines home from the veterinary clinic or livestock supply store.  When ordering vaccine online, it’s best to do it early in the week so that they won’t sit somewhere over the weekend.  Even though they are shipped in insulated containers with cold packs or dry ice, if they are too long in transit they may get too warm.

Scott E. Poock, DVM, DABVP, Associate Extension Professor, University of Missouri, says, “I am particular about how vaccine is handled when people are working cattle.  A pet peeve of mine is when people are using a modified live virus (MLV) vaccine and not keeping it cool, or have it exposed to sunlight.  Or they use MLV vaccine and if there is some left, instead of discarding it they decide to keep it and use it in a day or two.  This turns a really good modified live vaccine into a very poor killed vaccine,” says Poock.

“When we are working our own cattle, I like to have the MLV vaccines in 10-dose vials, and only mix up what will be used quickly—in less than an hour.  I sometimes have some 5-dose vials, so that if I end up with just 3 animals left to vaccinate I can mix up a 5-dose vial and not have to waste so many doses,” he says.

Once it’s mixed, he keeps the pistol-grip syringe in a cooler when not in use.  He uses a cooler with slots for those syringes, so the vaccine in the gun stays cool also.  Don’t contaminate a bottle of vaccine when refilling syringes.  se a different needle for taking vaccine from the bottle—not the one you’ve been injecting the cattle with.  “It’s also important to change needles often on the syringes you are using,” says Moore-Foster.  “Even if you don’t change needles after every injection, you should change them after you’ve injected several animals.  Needles tend to become dull after a few uses, and a dull needle not only causes more pain but also meat damage.  A dull needle also makes it harder to push through the hide and administer the vaccine,” she says.

Some vaccines keep quite a while when properly refrigerated, but if you’ve used part of a bottle, check it closely before using it again.  “I like to put a date on the bottle when I first puncture it, and then if it’s been sitting there for 6 months before I use it again, I might need to get a new bottle—especially if the color changes or it shows any other signs of having been contaminated,” she says.

“In some dairy herds we have to use a new, sterile needle with each individual animal to reduce the spread of Bovine Leukosis virus,” Poock says.

If he is using individual needles and a killed product, often he pulls those all up the night before (into individual-dose syringes) and keeps those refrigerated–and then in a cooler as he uses them.  This saves time when cattle are in the chute; he doesn’t have to keep changing needles and just uses an already-filled syringe for each animal.

“If it’s a modified live product, however, we have to wait until we start working the cattle, to mix it up, and then use individual needles.  In that situation I just mix one bottle at a time,” he says.

INJECTION PROTOCOLS – It’s always wise to use BQA (Beef Quality Assurance) protocols when vaccinating cattle, and this goes for dairy animals as well as beef cattle, since cull dairy cows or even some young stock end up as beef.  Always vaccinate in the neck, in the triangular region above the shoulder and below the top of the neck, staying away from structures like the bony column near the bottom and the ligaments at the top.  Never inject into the rump or back of the thigh.  Most people injected into the rump in earlier years because it was a handy spot to reach, and had thick muscle to absorb a large injection.  But that’s an area where an injection that creates scar tissue can damage the better cuts of meat, and is also hard to open and drain if an abscess ever occurs (as can happen with a dirty needle).

Keep track of where you give injections, even when you are doing it in proper locations on the neck.  “If I am giving multiple vaccines, I try to do an even number on each side, but also consistently give a certain vaccine on a certain side, says Moore-Foster.  Then if there’s more swelling or some kind of problem, it’s easier to know which vaccine caused it.  

“If we are seeing a lot of abscesses or irritation, I then have an idea which vaccine might be causing an issue, and have a better argument when calling the vaccine company to report a problem,” she says.

It’s also helpful to have some kind of system to mark or label the syringes when giving multiple vaccines, so a person never makes the mistake of putting a different vaccine in that syringe.  “This is especially important when giving modified-live vaccine; you want one syringe dedicated to that one, or to a killed vaccine, so things are not getting mixed up,” she says.

NEW CLOSTRIDIAL VACCINE – Hemorrhagic bowel syndrome (HBS) is sometimes a problem in dairies, caused by Clostridium perferingens type A.  This clostridial pathogen causes a highly fatal intestinal disease of adult dairy cows and has been called bloody gut and clostridial enteritis. The disease is seen most commonly in adult dairy cows early in lactation, although cases occasionally occur in late lactation or the dry period.  It usually occurs as an occasional disease on most dairies, although several cows may be affected in a relatively short period of time.  Some dairies struggle with this disease continually.

Affected cows become rapidly debilitated by the sudden and massive hemorrhage into the small intestine.  The disease comes on so quickly that they may simply be found dead or dying.  If the cow is still alive, her rectal temperature is often subnormal, due to loss of blood into the intestine and the resulting shock.  Feces of affected cows is dark and may contain dark red to black clots of digested blood.  As clots form in the intestine, it may become obstructed, causing some cows to become bloated and show signs of colic. Affected segments of intestine quickly die and occasionally rupture, resulting in fatal peritonitis.  Successful treatment of this disease is difficult.

Now there is a new clostridial vaccine called Covexin 10 that includes protection against type A.  It will be available in Canada by the end of this summer, and hopefully it will eventually be available in the U.S. as well.

It can be given to cattle from 2 weeks of age on up (sometimes calves get sudden fatal “enterotoxemia” caused by Type A rather than Type C or D).  The new vaccine can be used for immunization  against disease associated with infections caused by Clostridium perfringens type A, B, C, and D, as well as C. chauvoei, C. novyi type B, C. septicum, C. sordellii and C. haemolyticum and against tetanus caused by C. tetani.

This product requires two doses about 6 weeks apart, the first year, with an annual booster.  The animal will have full immunity to all components of this product by about two weeks after the primary course and this active immunity lasts about 12 months following the primary course of vaccination.