So what are they and what do they actually do?
There are 2 main types of contraceptives that are used in remote community work, one family is called progestagens, and the other main family is GNRH antagonists.
- The progestagens (MPA® or Covinan®) mimic female hormones that make the dog think it is pregnant By doing this, it stops the body’s production of eggs and hence acts as a contraceptive.
- GNRH antagonists (Suprelorin®) work in a different way by stopping the flow of oestrogen which will stop the dog becoming fertile.
Both of these types of drugs can be used successfully to reduce breeding of dogs in remote communities, but there can be side effects, so caution must be used.
What should we be looking for when trying to work out the best contraceptives for our community's dogs?
So why don't we jump straight for the GnRH antagonist (Suprelorin®)?
This means that for every Suprelorin® injection, 15 dogs could have had their 2 contraceptives each year.
The second problem is there is a very high risk of side effects. Some studies indicate that they can be as high as 60%.
So, it is our belief that it is better to use a progestagen for population control.
So when should we use them?
The contraceptive type ultimately depends on how frequent the programs are to be run:
One Visit per Year: If only one visit a year is available, then Suprelorin® can be used. One visit still misses any dogs that were born and reached a breeding age, so it is never ideal to have just one visit. Additionally, other contraceptives will not act for a long enough period. Using Suprelorin® can become a very expensive exercise and can often cost more than having another two to three visits each year.
2+ Visits per Year: If two or more visits a year are available, then it is better to go with the drug MPA. This is a cheaper option and is extremely effective. Another added advantage is that more regular visits allow more desexings to be performed, and ultimately provide longer lasting population control results in the community’s dogs.
Can anyone give this drug?
If you would like further information, please contact us on firstname.lastname@example.org or call 08 89723599.