Released in 1983 in Brazil and Germany, Farmyard Fun is a glitchy mess that only grew more and more unstable the longer I played it. It didn't actually crash while I was playing, so I feel that to be fair I'll give it a D- instead of an F ranking.
So in the game it looks like you're a farmer collecting eggs of the rectangular variety you can only find on the Atari 2600. Standing in your way are a bunch of chickens that later – as stages go on – evolve into what looks like ostriches or emu, and then other less identifiable types of bird. Down at the bottom of the screen is a stream along which swims what looks like a swan that you can, if you choose, ride along safely for awhile.
As far as the enemies go, the birds occasionally seem to react to your presence, though this may be bias on my part. At least, it looks like their behavior changes slightly when you get nearer to them, though for the most part they don't chase you. Some will run back and forth the length of the screen, but more problematic are those that just sort of wander around on top of a single egg, preventing you from grabbing it, until they happen to wander off with all the AI of an electric football game.
As I progressed level to level I did noticed increasing glitchiness, starting with a persistent screen flicker. After I was out of lives, I was able to continue running around the screen, unable to affect or be affected by anything. Is this programmed behavior or a glitch? There's no way to know for sure.
As far as the sound go, the background music is shrill and repetitive. I'd have preferred silence. The bird sprites are decent enough, at least enough that you can tell that they're birds.
Was the game fun? Eh, sort of? Enemy action seemed random, so the only strategy that mattered was "hang around until they move off of those eggs." As said, I give the game a D-, and that's maybe a bit generous.