How to Tell if Your Goat is Pregnant
I have had a few questions about how we've known Tater and Sweet Pea are pregnant, and what our preparation for their deliveries has been like. I'll preface this post by saying I am not (yet) an expert on expecting goats, but what little I've learned in my research and limited experience is hopefully helpful.

There are a few ways to tell if your goat is pregnant.
You can get an ultrasound done by your local vet. We had this done for Tater after the first time we tried to breed her, and it revealed that she was not yet pregnant. This can only be done thirty days or more after breeding, and while the ultrasound itself is not too costly, it is expensive to have your vet out to the farm to perform one, especially if you have to have more than one. It is, however, fairly fail-safe and gives you an idea of how many kids to expect in addition to just confirming or denying pregnancy.

A blood test is another pretty accurate way to know if your goat is pregnant. This can be done at 30 days post-breeding, and if you are comfortable drawing blood you don't need a veterinarian on hand. You can send the sample to a variety of places to have it tested, and the results are very inexpensive. A urine test can also be taken and sent in to certain labs.
In our case, we chose a bit of a wait and see method. The best way to tell if your goat is pregnant without a test is to simply monitor and see if she goes into heat again. With some goats (similar to how driveway breeding can be tricky) heat is very obvious, with others it is extremely subtle. We were pretty sure Tater was pregnant after a month, but with Sweet Pea I could barely tell when she was going into heat.

Gaining weight is not necessarily a sign of pregnancy. It actually can be cause for concern, as a bloated rumen is dangerous for your goats. However, a bloated rumen usually comes with other symptoms such as acting uncomfortable and difficulty breathing - signs that mean you should contact your vet.
Goats will bulge more on the right if they're pregnant, and more on the left if they are bloated. Our does were pretty trim going into their breeding, since they'd never been bred before, but with goats that have delivered before it can be impossible to tell by sight because they never really lose their "baby weight" after their first kids.

If after three weeks your doe doesn't go back into heat, and she seems to be gaining a little weight, she's probably pregnant. Keep monitoring her for signs of heat, and at about 15-16 weeks post-breeding you should start to see some swelling in her udder. This was how we confirmed Sweet Pea, who had stayed very slim, was pregnant.
Nigerian Dwarf goats will gestate for 145 days, and within the last few weeks before delivering their udders will swell more and you may even see the kid(s) moving. At about a month before your doe's delivery date, you should consider any vaccinations or vitamin boosts to help her with delivery and milk production. We are giving our girls CDT shots, BoSe shots, and a copper bolus as recommended by the farm that they came from, but everyone has a different pre-delivery regime.
Now it is time to start watching for signs of labor - Sunflower Farm has an excellent youtube video on Signs That Your Goat is Close to Kidding, which I'll be watching a few times in the next few weeks. And then we hope to be rewarded for our patience with plenty of bouncing, happy, healthy kids!
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