I have to gore-ly agree with zilvarwolf, at least until my stomach turned.
In a couple of my playthroughs, I setup a system consisting of four(4) 5x5 pens, setup as a quadrant (square). The exterior dimensions are 13x13, which is 5+5 (2x pens) plus a total of 3 wooden fences.
In the 1st quadrant is my Breeder fed with wheat. This makes cows make baby cows. I only need a few adult cows in here and they never move or get slaughtered. They reproduce.
Between this pen and the two(2) adjacent ones are Genotypers to move Babies only. This means babies get immediately moved out of the Breeder pen.
Between these two(2) pens and the last one are 2 more Genotypers, set to move Adults only. This allows the babies time to mature into adults. Facing into the last pen is the Slaughterhouse.
In summary:
1x Breeder pen w/3+ adult cows
2x "Maturing from baby to adult" pens that usually has between 5 and 8 babies (each) at any one time
1x Slaughter pen that instantly kills adults
From this, I got way more meat and pink slime than I could use. My goal was the MFR Laser Drill with pink slime. I also ended up getting enough meat to cook into ingots to last weeks/months in real life.