The animators thought it would be funny, plus they wanted Otis to fit a child's depiction of a cow (black and white w/ udders). They figured children wouldn't care. =/
It is supposed to be funny. Plus, it is considered socially acceptable to tunjuk an udder on tv. menunjukkan a bull's true anatomy would be considered inappropriate.
Despite being biologically male, Otis has an udder like the other male cows. In reality, only female cows have udders, not bulls. The reason all the male cows were designed like this in the franchise is because Steve Oedekerk figured that city folk thought that all cows would look like this. Both Genders Have udders in the movie Because They Were Designed like a cartoon classic cow with udder