Bangs vaccinations... conversation with state vet

[milkmaid]

So the WY state vet was in my Animal Science class today talking about his job (it's one of those lower-level classes designed because "we know 90% of you won't get into vet school, so here's what else you can do with your life")... anyway, he was talking about the Brucellosis aspect of it and I went down and quizzed him afterwards. Cleared up a few misconceptions I had so I'm passing my new info on to y'all...

1) Vaccinating bulls for brucellosis with the RB51 strain will not make them sterile. In fact, he said he knew several producers who routinely vaccinate bulls because they can be carriers as well if infected.

2) Vaccinating animals older than 12 months for brucellosis will not result in a high titer at slaughter. It was an issue with the previous vaccine (strain-19) but the regulations haven't caught up with the new vaccine yet. He said he's recommending many herds in the high-risk area (esp around Yellowstone National Park) vaccinate cows on a yearly basis.

Just FYI...

 

[larryshoat]

Thanks MM ! Vaccine technology is constantly changing .I'm confident that you will be in the 10% that does get into vet school .

Larry

 

[KNERSIE]

2) Vaccinating animals older than 12 months for brucellosis will not result in a high titer at slaughter. It was an issue with the previous vaccine (strain-19) but the regulations haven't caught up with the new vaccine yet. He said he's recommending many herds in the high-risk area (esp around Yellowstone National Park) vaccinate cows on a yearly basis.

The best protocol for high risk areas is to vaccinate heifer calves at weaning with Strain 19 and at 12 months with RB51, repeat at 18 months. After that no more vaccinations are required. Strain 19 should not be given after 9 months of age otherwise false positive titers may result.

Testing all your breeding age and older females in your herd every second year will go a long way in keeping your herd CA free. RB51 may not make bulls sterile, but they get a nasty reaction to the vaccination in their reproduction tract.

 

[milkmaid]

I'm having a hard time imagining bulls are going to respond that differently to a vaccine than a cow would.

As to strain-19, I'm actually not sure if it's still legal/available for use in the U.S. I would imagine it would provide more protection to use it as well. That reminds me; the state vet also said that RB51 (as standardly administered - one dose) is only effective 50-60% of the time.

The reason my area of the country has so much trouble with brucellosis is because the elk and bison carry it, and the high risk areas are the areas where people are feeding elk near cattle. The state vet said they're also vaccinating the elk in an effort to keep the brucellosis problem under control.

 

[Workinonit Farm]

I'm having a hard time imagining bulls are going to respond that differently to a vaccine than a cow would.

I don't find that to be too far fetched. Women do not respond as well to, or as effectively with certain 'heart' medications and/or treatments for different types of illness compared to men. People of different ethnicities also have proven to have different responses to certain medicines.
Just my 2 cents regarding the bull vaccination issue.

As to the rest of the info you posted, its very interesting and informative.
Thanks for posting it.

Katherine

 

[milkmaid]

So I ran a search for brucellosis info... figure we ought to have some facts here. I can't find the label for RB51 (was hoping that would have the info I wanted) so the rest of this will have to suffice.

Strain-19 was a problem in bulls and also localized in reproductive tissues of cows, and may be why producers are concerned about vaccinating bulls:
http://books.google.com/books?id=QQFDHB ... #PPA288,M1

Bison bulls can be vaccinated with RB51 for brucellosis with no side effects:
http://www.ncbi.nlm.nih.gov/pubmed/10407488

Brucella abortus itself does cause sterility in bulls:
http://edis.ifas.ufl.edu/VM026

RB51 is also safe in bull elk:
http://www.jwildlifedis.org/cgi/reprint/36/3/484.pdf

• RB51 vaccine (Lord et al., 1998, Buhrman, 1989, Uzal et al., 2000, Edmonds et al., 1999, Schurig et al., 2002):
  Description: B. abortus vaccine strain RB51 is a rough live attenuated vaccine. It is administered parenterally. This vaccine does not cause later diagnostic false positives.
  Efficacy:
  Rate: Efficacy rate of this vaccine is reported to be near 100% when heifers are vaccinated at 3 months, and 87% when vaccinated at 5 months.
  Duration: Unknown
  Contraindicator: Strain RB51 does not cause abortions in pregnant cattle, or appear to cause reproductive problems in mature bulls.

http://www.phidias.us/phinfo/topicSearc ... ensis.html

Also FWIW:
"...under certain conditions... vaccination of bovine females over 8 months of age may be approved with vaccines which do not interfere with standard serological tests, namely the RB51 vaccine."
http://www.fmvz.unesp.br/Eventos/Especi ... accine.pdf