Pasture per animal depends a lot on your
land and climate. In my area, more than one acre per standard-sized cow is needed for long term pasturage without rotation on a conventional small ranch, and that's without any goats in the mix. This is good bottomland, but it's in a drought-prone climate, and with a history of heavy grazing. So definitely look into stocking rates in your area to see what's typical. We currently have about 70 head of
cattle on ~250 acres in our bottom pasture (the best soil) and they must be supplementally fed a couple hundred pounds of meal and/or about 10 square bales of hay every couple days during winter, and occasionally during summer, and the grass is still rarely in great shape, but rather borderline overgrazed.
I do not have much
experience with mob grazing or rotation. Unfortunately, I am not in charge of the cattle operation, so it is run in a conventional manner. However, there are a couple points that I think your system will miss, based on my theoretical knowledge of the topic, which are these:
1) By confining the cows to a very small area for a short period of time, you force them to eat not just their favorite plants, but all the plants. If they are spread out and rotated infrequently, they will tend to re-browse their favorites again and again, eventually eliminating them and decreasing the quality of your pasture, even if to your eye there is still plenty of grass and forage (the composition will change even if the quantity does not)
2) Without rest, some grass will never get a chance to grow lush and tall while other grass is eaten to the ground; you will most likely just have a lot of borderline, stressed grass, and your pasture as a whole will be more prone to overgrazing
3) Your soil may gradually become more and more compacted if it is not rested between rotations
To determine if your cows need hay or other supplements to their grazing, the best thing is to look at their bodies, their
poop, and their behavior. You have some leeway with these metrics if you do not care about optimizing weight for sale, but it is good to keep an eye on them. If they are fat and their coats are shiny, they are doing well. If they are visibly bony around shoulders and ribs (this can vary by breed) and look poor, they probably need some supplemental feed. They will more likely need feed in cold weather, especially cold wet weather, or they will drop a lot of weight. If their poop is really green and runny (just sort of splashed out into big flat patties with no form) they need roughage. If it is darker and well formed with visible concentric "ripples", you are doing well. You can also get too much roughage in the diet (if they are not getting
enough fresh grass for some reason), and the pile will look more like horse poop, kind of in nodules instead of a nice patty. Cows will tend to eat from the buffet if you give it to them, but you can gauge how hungry they are by how they respond to additional food. Do they leave food in the trough for days, or eat it all within a few hours? Do they crowd around you or your vehicle hoping for food? If so they may need extra. If they are lying down in the shade early in the day or for long periods, they are probably content and well fed. If they never lie down and are constantly grazing, they may be hungry. If your pasture is visibly overgrazed, they may be hungry. If milk production is abnormally low or calves are not growing well (if you keep the calf with the mother), they may be hungry.
Hope this helps somewhat!
