To find the most up-to-date information on the sheep population in the US, I recommend checking reputable sources such as:
* The United States Department of Agriculture (USDA): They publish agricultural statistics, including livestock numbers.
* The National Agricultural Statistics Service (NASS): They are a branch of the USDA that collects and analyzes agricultural data.
* The American Sheep Industry Association: This organization advocates for sheep producers and provides information about the industry.
You can find these organizations' websites online.