(at around 43 mins) After the farmer has been knocked out and the animals attempt to make it appear as though a branch fell on him while reading against a tree, we see from the farmer's point-of-view that Otis places the book on the farmer spine-first with the open pages facing out. However, in the next shot the book is lying open on the farmer with the pages down and the spine facing away from him.
(at around 53 mins) When Mr. Beady is asleep in his stuffed chair, he is shown holding a beer in his right hand. Also shown is a doily laying on the table next to him to his right. He wakes up in the next shot and immediately lifts up a six-pack of beer with his left hand from the floor next to him. The beer that was in his right hand has disappeared, and the doily is now on the arm of the chair and not on the table.
(at around 5 mins) When Otis and the gang fly through the air on the surfboard at the start, the characters switch places twice while still in the air.
A tractor appears in various scenes. The rear tires on the tractor are on backwards - the tread for tractor tires is designed to push mud out away from the tire when rotating forwards, to keep the treads from filling with mud. These tires would pull mud into the tread, making the tire slick and useless in deep mud.
(at around 41 mins) After the farmer has been knocked out and Pip sits on the man's wrist to feel the pulse, Pip is sitting on the "pinky" side of the hand. The radial pulse in the wrist is detectable on the "thumb" side of the hand. However, the cubital pulse, though usually weaker, can be felt on palpation in most people.
Yes, the male cattle have udders; it's a joke.