Really fun! I liked the mix of farming sim and tower defence! Kinda reminds me of the towermadness series where you had to protect sheep from aliens for some reason!
I think there's a few key things here: I think some of the UI buttons don't display properly: particularly those around fertilizer. Also a key problem I found is there was no quick way to collect milk, so while the milk the ooplets consumed raised exponentially, I had no way to seize on my mass of cows (also making feeding them kinda pointless since I wasn't likely to milk a cow more than once every 30 seconds).
I didn't see any reason to sell levelled up cows, which would also help encourage feeding. Finally I think some automate the selling of cows would be interesting! Some music would be lovely too!
Overall though I had a really fun time with this! Thanks for submitting!