Formulating Starter Diets to Meet Nutrient Requirements of Dairy Calves During Rapid Early Growth

Abstract Text: The importance of calf starters in enabling calves to make the transition from milk to solid feeds is well known.  Starters must be palatable to encourage intake, must contain easily fermentable and digestible ingredients, and must provide a balanced profile of absorbed nutrients.  With the renewed interest in providing increased nutrients from milk or milk replacer early in life, however, the optimal formulation of starters to enable calves to make the transition without slumps in growth remains controversial.  The largest uncertainties lie in predicting rates of ruminal carbohydrate fermentation and the resulting microbial protein synthesis.  Demonstrations of the benefits of fermentable non-starch polysaccharides such as soluble fiber have created opportunities for blends of carbohydrates beyond traditional cereal starches and forage or cellulosic by-product ingredients.  Increasing metabolizable protein supply has shown promise in helping calves maintain high pre-weaning growth rates as they transition to solid feed diets.  The most important advances likely will be made by changing the focus from product formulation to formulating diets that support a defined level of performance.  Further progress in modeling would be complemented by additional research to define ruminal dynamics in young calves.

Keywords: Calves, starter, growth