The study looked at how low phosphorus intake affects calcium and phosphorus levels in growing dogs. They fed some puppies a diet low in phosphorus and others a balanced diet. The puppies on the low phosphorus diet had lower levels of phosphorus in their blood, especially the smaller Beagles. Their calcium levels went up, showing a close relationship between calcium and phosphorus levels. The puppies on the low phosphorus diet also had lower parathyroid hormone levels and higher alkaline phosphatase activity at certain times. This suggests that phosphorus plays a crucial role in the skeletal development of growing dogs.