Cow diets vary depending on the age of the animal, and the types of crops that are available on the farm, which can vary throughout Canada depending on climate and soil types. Calves, for instance, drink milk for a few months, but start eating grain and hay when they are a few weeks old. As they grow older, they can eat more hay and solids. Cows’ diets are optimized: Farmers grow most of what we feed our cows, and work with cow nutrition experts who regularly analyze the nutrient content of their crops, and make recommendations on the mix of crops and other vitamins, minerals and nutrients - macro and micro - so a ration will meet the needs of the lactating cows. Farmers constantly monitor cows and the vet checks up on them as well. If farmers think something may not be quite right, they work together with vet and feed expert to adjust the diet if needed.