What behaviors of the express messengers bothered Buck?

The behavior that most bothered Buck about the express messengers was their neglect in feeding and watering the dogs. Throughout "The Call of the Wild," Buck experiences a transformation as he adapts to the harsh realities of life in the wilderness and as a sled dog. Proper care, including adequate food and water, is crucial for the strength and endurance of the dogs, especially in the grueling conditions they face. Buck’s frustration stems from the lack of attention and care that directly impacts the health and performance of the team. The neglect shows a fundamental disregard for the well-being of the animals, which stands in stark contrast to Buck's developing instincts and his understanding of the importance of survival and teamwork. This neglect not only affects Buck's physical condition but also his trust and loyalty towards the express messengers, deepening the divide between the domesticated life he has known and the wild instincts he is beginning to embrace.