Designing Calf Starters That Optimize Growth

According to Hill, 20 published trials show an increase in average daily gain (ADG) as starter consumption increases. That means that good starter intake could lead to earlier weaning. Hill said research shows calves with birth weights of greater than 100 pounds should consume at least 2 to 2.5 pounds of starter several days before weaning. Calves with birth weights between 50 and 100 pounds should consume between 1.5 and 2 pounds of starter several days before weaning.

Hill said fibrous feeds (hay, soyhulls, cottonseed hulls, etc.) have been shown to reduce starter intake. That’s likely because these high-fiber feeds increase gut fill, but are inadequately fermented and digested in young calves’ rumens. Thus, Hill said grains should make up at least 60 percent of the starter. He said research has not shown a difference in calf performance between processed and whole corn. In fact, processed corn may actually negatively impact intakes because it may lead to increased fine particles in the starter. Research shows the presence of fine particles in starters can negatively impact intakes.

Hill said research provides no clear answer of whether textured or pelleted starters are better. In fact, several trials show no difference in performance when nutrient composition is the same between pelleted and textured feeds.

One potential negative implication of pelleted starters is a greater risk of parakeratosis of the rumen papilla. Parakeratosis is the collection of dead tissue on the absorptive projections in the rumen. As a result, nutrient absorption decreases. Some research suggests that textured diets provide the abrasiveness required to “clean off” this dead tissue and allow for adequate absorption.

Research trials show that starters should contain 18 percent crude protein to support maximum growth. Hill said it appears soybean meal is the best protein source in starters with no significant improvement in performance with the addition of other sources, such as heat-treated soybean meal, roasted soybeans or other plant or animal proteins.

Hill suggested that high levels of molasses (greater than 10 percent) actually decrease ADG versus lower amounts. Added fat or oil also reduces intake and, even in cold weather, doesn’t show an improvement in ADG.

On the other hand, the addition of specific fatty acids – butyrate, medium chain fatty acids and linolenic acid – have shown improvements in ADG, frame growth, feed efficiency and reduced scouring. That’s likely because these fatty acids simply aren’t included in most calf feeds. Adding them helps the calf overcome deficiency. They are also known to act as metabolic and immune function regulators.

Finally, Hill reminded calf raisers that coccidiosis remains a problem in calves, especially weaned calves. Including approved coccidiotstats – decoquinate, lasolocid and monensin – is advised as calf raisers struggle with challenges such as loose manure and unthrifty calves.