Access to food for any animal is determined by its ability and intellect. Humans are a unique species and have many culinary practices that would be unusual for other animals, such as preparing and cooking meals.
Humans are the only species to consume the milk of another species.
All species instinctively seek out nutritious food as it is central to survival. Around 7,500 years ago, humans realised that they could milk certain animals to access a rich source of nutrients and this is how dairy farming began. Other animals do not have the ability or intellect to milk another species as a source of nutrition but when they have access to milk, many will readily consume it. Typical examples of this are domestic cats and wild birds.