Recent discussions in the sheep farming management column addressed the topic of clostridial vaccination in lambs. This sparked strong interest among some farmers and generated many follow-on questions, focusing on optimum handling of vaccines and correct administration.
Product selection should take into account the disease profile risk and history on the farm
We spoke with Sarah Campbell, veterinary technical adviser with MSD Animal Health, to get a specialist’s view on best practice recommendations, to ensure the investment farmers make in vaccines is money well spent.
Speakers at the sheep event in Cookstown were Sarah Campbell from MSD Animal Health and John Grant from Parklands Veterinary Group.
Product selection should take into account the disease profile risk and history on the farm. This will be helped where an accurate diagnosis has been made in the past and suspect deaths are sent for post mortem analysis.
Disease risk
There are some farms that are unfortunate enough to face a significant challenge with clostridial diseases and pasteurella. In these circumstances, selecting a combination product is a straightforward decision. The threat of pasteurella is so great that a booster dose may be required two to three weeks before the next risk period. For many farmers, this occurs in August or September.
The main clostridial disease of note, covered in vaccines offering protection against 10 strains of clostridia, is Sordellii. Where there is a history of Sordellii on the farm, a 10-strain product should be used. Where pasteurella and Sordellii are an issue, then a combination of products will be required.
Clostridial vaccines can play a vital role in livestock production. They represent a significant cost to the system, but can quickly provide an economical return where mortality is prevented. It is critical that they are used correctly, as incorrect handling or administration could render them useless and a waste of money.
I am vaccinating lambs aged eight to nine weeks old this week. All the lambs will be sold over the summer months. Do I need to administer a second treatment or will one vaccination suffice?
This is one of the most common questions our technical advisory team receive. No protection is expected from the first dose. This is the priming shot and protection is not expected until two weeks after the primary course has been completed. All lambs should receive two doses of a combined clostridial and pasteurella vaccine to stimulate their own active immune system. The graph using Heptavac P-plus as an example demonstrates how active immunity develops and clearly shows how the second vaccination is required to provide optimum protection.
Figure 1. The development of active immunity against clostridial diseases. Two shots are required to develop protection.
For how long can I transport the vaccine without having it in a fridge?
It is not a question of how long the vaccine can be transported for, as there are so many variables such as how warm a day it is, the temperature in the vehicle and where it is stored during transit. The vaccine needs to be maintained at the optimum temperature, which is generally between 2°C and 8°C. The ideal situation is where vaccines are stored in a cooler bag during transit that will maintain this temperature range.
Can freeze packs be used when storing the vaccine?
It is equally as damaging to the efficacy of the vaccine if the temperature falls below 2°C or rises above 8°C. A freezer pack can be used strategically if the vaccine is protected and it aids in maintaining the temperature range. Bubble wrapping the vaccine can help to protect it from freezing, while maintaining the environment at the desired temperature.
While on this point, it is important to know the temperature in your fridge, as some fridges can freeze items stored in a certain position such as at the back of the fridge, which can harm the vaccine. We have also seen cases where vaccines have been stored in an old fridge in the farm yard that is not capable of maintaining steady temperatures.
How long will the vaccine remain effective once the seal is broken?
When handled correctly clostridial disease vaccines will typically maintain their efficacy for a period of eight hours, with some products citing a slightly longer window of 10 hours. Examples of incorrect handling that would reduce this window of efficacy include leaving the vaccine in direct sunlight and exposed to high temperatures, or using dirty equipment to administer it.
If I only pierce the seal with the spike of the automatic gun and do not remove the bottle, will this maintain an airtight environment and allow the vaccine to be stored for longer?
This is a query we frequently get, along with similar ones asking if the rubber bung at the top of the bottle can be sealed with anything from sellotape to silage tape. Once the seal of the bottle is broken, there is no way of extending the window in which the vaccine can be used. It is important for this reason to purchase a bottle that best suits the number of doses you require or the number of animals you can realistically handle and treat in the timeframe.
Manufacturer guidelines recommend changing the needle between each animal. How realistic is this?
This is recommended to ensure the vaccine solution is kept sterile and is not contaminated by using the same needle. However, we have to be realistic and recognise that it won’t always be possible to use a new needle for each animal. There is a happy balance between the frequency needles are changed and protecting the efficacy of the vaccine. This needs to take account of how the needle is handled and the risk.
For example, if the fleece of a lamb was dirty and risked contaminating the needle, or if the syringe had to be left down in between use in a poor environment with a high risk of bacteria, then it should be changed after use. The advice would generally be to change the needle as frequently as possible, at least after each race of lambs or after five to 10 lambs or so. It is also worth pointing out that where an automatic injection gun is being used, then it is important to ensure it is washed thoroughly before use.
The advice where possible is to administer the vaccine on a dry day. What is the reasoning behind this?
This is aimed at protecting the efficacy of the vaccine. Administering the vaccine when the animal is wet increases the risk of bacteria being mobile on the skin. If skin bacteria contaminate the needle, there is a higher chance of injection site abscesses developing.
Recent discussions in the sheep farming management column addressed the topic of clostridial vaccination in lambs. This sparked strong interest among some farmers and generated many follow-on questions, focusing on optimum handling of vaccines and correct administration.
Product selection should take into account the disease profile risk and history on the farm
We spoke with Sarah Campbell, veterinary technical adviser with MSD Animal Health, to get a specialist’s view on best practice recommendations, to ensure the investment farmers make in vaccines is money well spent.
Speakers at the sheep event in Cookstown were Sarah Campbell from MSD Animal Health and John Grant from Parklands Veterinary Group.
Product selection should take into account the disease profile risk and history on the farm. This will be helped where an accurate diagnosis has been made in the past and suspect deaths are sent for post mortem analysis.
Disease risk
There are some farms that are unfortunate enough to face a significant challenge with clostridial diseases and pasteurella. In these circumstances, selecting a combination product is a straightforward decision. The threat of pasteurella is so great that a booster dose may be required two to three weeks before the next risk period. For many farmers, this occurs in August or September.
The main clostridial disease of note, covered in vaccines offering protection against 10 strains of clostridia, is Sordellii. Where there is a history of Sordellii on the farm, a 10-strain product should be used. Where pasteurella and Sordellii are an issue, then a combination of products will be required.
Clostridial vaccines can play a vital role in livestock production. They represent a significant cost to the system, but can quickly provide an economical return where mortality is prevented. It is critical that they are used correctly, as incorrect handling or administration could render them useless and a waste of money.
I am vaccinating lambs aged eight to nine weeks old this week. All the lambs will be sold over the summer months. Do I need to administer a second treatment or will one vaccination suffice?
This is one of the most common questions our technical advisory team receive. No protection is expected from the first dose. This is the priming shot and protection is not expected until two weeks after the primary course has been completed. All lambs should receive two doses of a combined clostridial and pasteurella vaccine to stimulate their own active immune system. The graph using Heptavac P-plus as an example demonstrates how active immunity develops and clearly shows how the second vaccination is required to provide optimum protection.
Figure 1. The development of active immunity against clostridial diseases. Two shots are required to develop protection.
For how long can I transport the vaccine without having it in a fridge?
It is not a question of how long the vaccine can be transported for, as there are so many variables such as how warm a day it is, the temperature in the vehicle and where it is stored during transit. The vaccine needs to be maintained at the optimum temperature, which is generally between 2°C and 8°C. The ideal situation is where vaccines are stored in a cooler bag during transit that will maintain this temperature range.
Can freeze packs be used when storing the vaccine?
It is equally as damaging to the efficacy of the vaccine if the temperature falls below 2°C or rises above 8°C. A freezer pack can be used strategically if the vaccine is protected and it aids in maintaining the temperature range. Bubble wrapping the vaccine can help to protect it from freezing, while maintaining the environment at the desired temperature.
While on this point, it is important to know the temperature in your fridge, as some fridges can freeze items stored in a certain position such as at the back of the fridge, which can harm the vaccine. We have also seen cases where vaccines have been stored in an old fridge in the farm yard that is not capable of maintaining steady temperatures.
How long will the vaccine remain effective once the seal is broken?
When handled correctly clostridial disease vaccines will typically maintain their efficacy for a period of eight hours, with some products citing a slightly longer window of 10 hours. Examples of incorrect handling that would reduce this window of efficacy include leaving the vaccine in direct sunlight and exposed to high temperatures, or using dirty equipment to administer it.
If I only pierce the seal with the spike of the automatic gun and do not remove the bottle, will this maintain an airtight environment and allow the vaccine to be stored for longer?
This is a query we frequently get, along with similar ones asking if the rubber bung at the top of the bottle can be sealed with anything from sellotape to silage tape. Once the seal of the bottle is broken, there is no way of extending the window in which the vaccine can be used. It is important for this reason to purchase a bottle that best suits the number of doses you require or the number of animals you can realistically handle and treat in the timeframe.
Manufacturer guidelines recommend changing the needle between each animal. How realistic is this?
This is recommended to ensure the vaccine solution is kept sterile and is not contaminated by using the same needle. However, we have to be realistic and recognise that it won’t always be possible to use a new needle for each animal. There is a happy balance between the frequency needles are changed and protecting the efficacy of the vaccine. This needs to take account of how the needle is handled and the risk.
For example, if the fleece of a lamb was dirty and risked contaminating the needle, or if the syringe had to be left down in between use in a poor environment with a high risk of bacteria, then it should be changed after use. The advice would generally be to change the needle as frequently as possible, at least after each race of lambs or after five to 10 lambs or so. It is also worth pointing out that where an automatic injection gun is being used, then it is important to ensure it is washed thoroughly before use.
The advice where possible is to administer the vaccine on a dry day. What is the reasoning behind this?
This is aimed at protecting the efficacy of the vaccine. Administering the vaccine when the animal is wet increases the risk of bacteria being mobile on the skin. If skin bacteria contaminate the needle, there is a higher chance of injection site abscesses developing.
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