I went back to the vets to get this for my male again, he's been off it for about 2 yrs and back then it lasted 6 months only, today I was advised that it lasts for 12mnths now.

Does anyone know what the changes are in it for it to last longer? Or is there no change and they know more info ok it's working

You get a choice of either a 6 month or a 12 month one, you must just be getting the bigger one now :-)

Only used it on one dog and it was the one that is supposed to last 6 months but it lasted for 14 months - by the time I returned for the second shot that I had paid for it was out of date.

I used the six month one but it only lasted four.

That's interesting to know that there is 2 different length of times to them.
It worked very well on him before and now at £40 for 12 months it makes it ever cheaper and absolutely no question that it means no castration unless medically he needs it!!

£40 for the 12 month jab?????? I'VE JUST PAID £100 Grrrrrrr :'(

Yup, I don't know if it was a mistake to charge me that as I know a few years back they got the 6mnth one down to £30, however I left paying £41 in total and she read out the paperwork saying 12mnths as I questionned her about it.

I did pay out £90 I think it was when I first ever used it, the vets hadn't ever before either and saw the results and use it all the time now hence the price reducing somewhat..