Choosing the Right Progesterone Device

Vetoquinol Australia

With spring breeding just around the corner and producers all across the country securing this years’ sires, planning for spring joining is already well underway. One thing that may not be on your radar yet, or at all, is choosing the right progesterone device for your AI program.

Most producers simply use the device they are provided without realising there is a choice out there and there may be an alternate device that better suits their needs and requirements. Some questions you may not have asked or considered include: · are all devices created equal? · is there a “right dose” when it comes to progesterone? · when do you use a “low dose” device? · can you reuse a device? · are some devices too big for heifers?; and · which device is the most environmentally friendly? If we take a step back, let’s look firstly at what a progesterone device is and what role does it play in a synchronisation program.

What is a progesterone device?

An intravaginal progesterone device is used to elevate the blood progesterone levels to mimic the normal rise in progesterone during the oestrous cycle of a cow. A drop in progesterone, coupled with a rise in other hormones is what signals ovulation. By artificially increasing the level of progesterone with a device, we can start to synchronise a mob of cows regardless of where they are in their normal cycle or we can induce a cow to cycle if she is currently not cycling at all. A progesterone device can be used on its own or combined with other hormone injections to control either oestrus or ovulation.

Choosing the right device

There are multiple devices on the market and they all contain progesterone – so do they all work in the same way? Mostly yes; they all deliver progesterone through extraction via mucous flow around and through the device with the progesterone being absorbed through the mucosal lining of the vaginal walls into the blood stream. So the first step in choosing the right device starts with considering the females in your selected AI group and how much progesterone they are likely to need to maintain sufficient progesterone for the full synchronisation program. Larger animals may require more progesterone, and smaller or young animals less, so it may be advisable to contact an expert to discuss the specific requirements for your herd. There may even be different recommendations within your herd. If you are looking to maximise the results from your program or improve your previous result by a few percent, then it may not be a one size fits all approach. There can be just as large an impact on results by having too little progesterone as too much, so it’s important to get this right.

Low dose devices

Using low dose devices in cows means they sometimes run out of progesterone a day or two before the device is scheduled to be removed. It is therefore important to keep an eye out for any early signs of oestrus (or use an Estrotect® patch) and advise your vet or technician immediately. This can be a costly mistake as you may not only incur the AI costs but also skip a whole cycle meaning their progeny will be born later and will be lighter as yearlings or replacement heifers. On the flip side heifers may benefit from a lower dose. If there is too much progesterone in the blood stream, there may not be a sufficient drop in progesterone levels to enable the rise of other key hormones necessary to initiate ovulation. If this is the case, heifers could ovulate well after the insemination date or fail to respond completely, thereby producing poor and costly results. It is therefore worthwhile ensuring you use the optimal dose for the animals you are synchronising.

Can I reuse a device?

This is one of the most commonly asked questions around devices and the easy answer is that the Cue-Mate® is the only device with a registered re-use claim (which applies only to the wishbone). There are a number of risks and disadvantages when reusing a device but the biggest one is that there is no way of telling how much progesterone is left in a device after it has been used. If you do reuse a devise (off-label or against the manufacture’s recommendation); you run the same risk as using a device with insufficient progesterone.