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Minimise Your Botulism Losses Due to Missed Mustering

Minimise Your Botulism Losses Due to Missed Mustering

Minimise the Effects of Missed Mustering Cattle that are missed at mustering are at risk of contracting botulism and dying because they miss out on vaccination. SingVac® 3 Year Single Shot Bivalent Botulinum Vaccine for Cattle reduces the risk of losses in unvaccinated cattle and offers the best herd protection from the effects of missed mustering. The following tables explain how.

Comparison of Protection by SingVac 3 Year Vaccine vs. a Conventional l-year Vaccine

Let’s compare the protection levels over three years between two herds: one vaccinated with conventional botulinum vaccine and one vaccinated with SingVac 3 Year vaccine. Let’s assume that: -

  • Herd size is 1000 cattle at the star t of the three years (no replacements are introduced)
  • Only 80% are vaccinated each year (20% missed mustering)1

Table 1 shows that using a conventional vaccine, 800 animals will be vaccinated each year, leaving 200 unvaccinated, and therefore susceptible to botulism. Each year, a different group of 200 cattle will miss the muster and remain unprotected for one year. This means that a total of 600 cattle could be unprotected at some stage during the 3 year period.

On the other hand, if the herd is vaccinated with SingVac 3 Year vaccine, the 800 animals vaccinated at the first muster will be completely protected for the entire three-year period. That means that a maximum of 200 cattle will be susceptible to botulism during the three-year period, each for three years. You may even be able to reduce the number of untreated cattle with SingVac 3 Year vaccine at the year 2 muster, if you notice any cattle missed the previous year.

missed mustering table

So due to missed mustering:-

With conventional vaccine, 200 head are exposed each year for 3 years = 600 cattle.
With SingVac 3 Year vaccine, 200 head are exposed for 3 years = 200 cattle.

There is no difference between a herd’s level of exposure between these two products where outbreaks are sporadic in any given year. However, this is not the case where botulism is endemic.

Comparison of Botulism Deaths Using SingVac 3 Year Vaccine vs. a
Conventional l-year Vaccine in an Endemic Area

Now, let’s repeat the model above, but add in another important assumption:-

  • Botulism is endemic and 15% of unvaccinated cattle die each year

Table 2 below shows that using a conventional vaccine, 200 cattle will miss the year 1 muster, remain unprotected, be exposed to botulism and 30 will die (15% mortality rate). At the year 2 muster, the herd will only be 970 cattle in size. Again, 20% will miss this muster (194 animals) and 29 will die from botulism over the following year. In the year 3 muster, 188 animals will be unprotected and 28 will die. According to the model, over the three-year period, a total of 87 cattle would die due to missed mustering when using a conventional vaccine.

With SingVac 3 Year botulinum vaccine, 800 cattle are vaccinated in the first year and 200 animals are unvaccinated due to missed mustering. Of these 200 animals, 30 will die from botulism. In year 2, one hundred and seventy animals remain unvaccinated and 25 succumb to botulism and die. In the third year of the program, 145 animals remain unprotected and 21 die. However, the 800 cattle vaccinated with SingVac 3 Year vaccine will be fully protected for the entire three-year period. This means 11 fewer cattle will be lost due to missed mustering using SingVac 3 Year vaccine compared to a conventional vaccine. At current prices, this could equate to as much as $6,780 in stock losses per 1,000 cattle. There are also the additional labor and vaccine costs associated with annual vaccination, and the model shows the vaccine component alone amounts to an additional $346.

All up, the costs of annual vaccination are significant compared with the SingVac 3 Year program. Adopting a three year program could deliver savings of up to $7,126 per 1,000 cattle compared to annual vaccination programs.

missed mustering table

Conclusion

The assumptions used in this model are considered a reasonable comparison to the field situation. It assumes a high challenge where 15% of unprotected cattle die. In reality, this will not always be the case, where some years the challenge will be a lot less and in others, a lot more. Furthermore, the missed mustering rate will vary from property to property, however it illustrates an important point.

Regardless of the rate of missed mustering and regardless of the severity of the challenge, SingVac 3 Year Botulinum Vaccine will provide the best herd protection from the effects of missed mustering.


1. Meat & Livestock Australia Final Report, Northern beef situation analysis. Project Code; BNBP0518, August 2010.
2. Model assumptions: The model follows a par ticular group of cattle in an endemic area over a three-year period, and assumes that there is no replacement cattle brought into the herd. It assumes that cattle are vaccinated are protected against botulism for the duration of the claim on the vaccine label. It compares the potential exposure to botulism due to missed mustering between two identical herds with a fixed mustering rate and a fixed botulism challenge rate, with the only difference being the vaccination program used:- an annual vaccination program with a traditional vaccines that gives 12 month protection vs. a three-yearly program using SingVac 3 Year Vaccine that gives three years protection from a single dose.

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