You can test milk for estrus, ketosis, mastitis and pregnancy very easily.
Estrus Detection
P4 Rapid detects the level of progesterone in her milk.
All my cows have silent heats. This means they don’t moo (which is a good characteristic in a semi urban area) and thus heat detection is impossible. As most cows stand at night you are really taking a stab in the dark. You can inject with Estrumate, a synthetic prostaglandin, and depending on where your cow is in her cycle she may come into season 2-4 days post injection or require a second injection 11 days after the first and then she will come into estrus.
So P4 Rapid is a very handy tool. You can use it post Estrumate to see if insemination is likely; you can use it 20 days after insemination to see if your cow is pregnant or will she need another insemination?
Idexx Bovine Pregnancy Test
This test is invaluable but if you rely on it alone you have lost 21 days.
Farmwest in Bunbury will send you sample vials with a little preserving tablet. From day 30 you can take a mid milking sample and send it to them and they will carry out this test. I always use this as a follow up and if I’m in any doubt about a cow I will also send another just before I dry her off to make sure nothing has gone wrong. It costs around $8.
Ketosis
If your recently calved cow suddenly loses weight, goes off her food and her milk supply decreases dramatically she may have ketosis. PortaBHB test strips are very handy. Just dip one into the milk and compare the colour with the chart. If you suspect Ketosis call your vet as she could die. She has to be treated quickly to restore her appetite and milk supply.
I’ve only had one case and fortunately caught it early. It was during winter so I had to rug her throughout the winter as she lost so much weight.
Mastitis
Mastitis can occur at any time during lactation but is most common straight after calving when your cow has a huge udder and it is hard for you to milk her as her teats are swollen.
Squirt some milk from each quarter into the paddle, tip it sideways until the milk lines up with the line on the paddle (you’ll understand when you see it) and put 2 squirts of the solution into each and then just swirl it around. If it is granular she has mastitis and if it looks like milk it’s ok. Many cows are just swollen post calving and it can feel as if they have mastitis when they don’t. This takes the guess work out and saves using unnecessary anti-biotics. If in doubt call the vet. She can end up with three quarters or worse still die. The best remedy and preventative treatment for mastitis are several hungry calves.
Local House Cows 