I just remembered 'the Animals of Farthing Wood'. Looking at it now, it's almost unbelievable a show this dark, depressing and sometimes gore-filled (well, that's how I remember it) was made for kids, but back in the day, it was just normal.
I vaguely remember another show with armies of animals that actually had all-out wars. There were like divisions of Rhinos and Bisons, I'm not joking. I can't remember anything clearly though. As outrageous as the concept sounds, it's just the kind of thing you'd expect in Brikwars, except it was on television and for kids.