This is always one of the most daunting tasks to undertake for the first time. If you have no experience with injecting, as I didn't, you'll wonder what the heck you're meant to be doing.
How hard do you need to push the needle to break the skin? How far does the needle go in? But, it's ok, it isn't as bad as it looks.
The first time you do it you will most probably get it wrong, which is ok, you have to get the feel of what you're pushing the needle through and how the cow reacts when you inject the fluid.
So, what's the best way to do it?
First thing you want to do is practice on something non-living... like a potato or a swede! Get yourself a needle, hold it between your first finger and middle finger, needle facing outwards. Have a tight grip, push your thumb under the bottom of the needle for support and then close your hand into a fist-shape. Get your chosen vegetable and after 3 practice jabs, perform a swift jabbing motion into the object. You want to be aiming for a specific point and until you can accurately punch through this point 3 times in a row, do not try it on cows! The better your aim and strength, the better it will feel for the cow.
So, on a cow, for an intramuscular injection, where do you aim?
I have been taught this injection site because it is A) the safest to administer B) the easiest to get to in a parlour.
The first you want to do is make sure that the cow is fed. Take the needle, without the syringe attached and place it between your fingers as described before. With the side of your palm, give two warning hits on the site of injection (this tends to desensitise the area slightly) and on the 3rd hit, swiftly push the needle through the skin in the area shown above. The star regions are the optimal positions, followed by orange and then red circles.
It is normal for the site to bleed a little, but if there is excessive blood DO NOT ADMINISTER THE INJECTION. It is most likely that you have hit a vein and some fluids cannot be given intravenously or they may cause death so... remove the needle slowly and try the other side of the cow.
In normal situations, once the needle is in, attach the syringe and expel the fluid at a constant rate while rubbing around the area.
This method is usually avoided when injecting beef cattle because the rump is a valuable part of the carcass. For dairy cattle, the carcass is less of a valuable point therefore this site can be used.