In the beginning of the book, Jody enjoys the dogs and views them somewhat as companions.

After the frenzied greeting the dogs lowered their noses to the ground in a businesslike way and went ahead, looking back now and then to make sure that the boy was coming. (ch 1, p. 4)

The dogs keep him company only as long as he is interesting.  The first time Jody sees the dogs, he sees buzzards.  He hates the buzzards because they live off death.  The buzzards, appearing with the dogs, foreshadow the death Jody will see in connection with animals.

Jody describes the time when he gets his pony Galiban as “a strange time and a mysterious journey…-an extension of a dream” (ch 1, p. 13).  At this time, the dogs greet him with suspicion until they see it’s him, and then with wagging tails.  Once he has his pony he ignores the dogs.

When the horse gets sick, Jody’s father compares it to a dog.  Jody is still worried about the horse being in the rain.

"A little rain never hurt anything," Billy assured him. Jody's father joined the conversation then and lectured the boy a little. "A horse," he said, "isn't any lap-dog kind of thing." (ch 1, p. 23)

When Jody’s pony dies, the boy becomes less innocent.  His new jadedness shows through in his treatment of the dogs.

Then at the ranch house he baited a rat trap with stale cheese and set it where Doubletree Mutt, that good big dog, would get his nose snapped. (ch 2, p. 35)

Jody is bored.  He says he was not moved by cruelty, but “torturing” the dog, as his mother says, is a cruel thing to do.

The dogs seem to watch over Jody as he grows up.  They are nervous and excited when he shoots.  They want to go with him to kill mice. 

He tried to whip up his enthusiasm with thoughts of the fat juicy mice. … The dogs coaxed and whined about him, but he could not go.  (CH 4, p. 90)

Jody is grown up.  Experience has tired him.  He can no longer find joy in the simple pleasures he used to share with the dogs.