Finding the Ideal Calf Starter

The physical particle size of calf starters has been a topic researched for decades. However, there is still no concrete answer to the age-old question: what is the most ideal calf starter to feed? There are so many other factors that come into play when discussing calf starters, including forages being fed, what type of bedding calves housed on, how soon calf starter is offered, how much calf starter is being fed, and more. While the type and characteristics of a calf starter are essential, the management practices of the calf program are just as crucial in determining how calves grow and develop. This article will look into recent research and management practices associated with different calf starters.

One of the most important aspects of feeding a calf starter is to ensure that all calves have access to small amounts of starter and fresh, clean water starting at day three of life. While calves will not rapidly consume starter at this age, having it present to encourage and entice that calf is very important. Because we want calves to begin to consume starter at an early age, all starters should be fresh, clean, free of mold, and be placed where calves can easily access it. Rumen development is initiated once calves begin to consume small amounts of grain. The fermentation of the starch produces butyric acid, which is responsible for the development of papillae on the rumen wall. A calf needs to eat a half pound of grain for 21 to 28 days for adequate rumen development to occur. Rumen development is essential for that calf to be able to handle the nutritional changes as she moves from a liquid diet to a diet of all solid feeds and subsequent forage diets. Therefore, offering calves their starter grains at an early age is the most critical step in developing their digestive systems.

Because it is important to get calves to consume starter grains at an early age, it is critical to remember the inverse relationship between liquid feeds and starter intake, as shown in the graph below. The more liquid feed a calf consumes, the less starter the calf will consume. As a calf ages, they should naturally begin to fill their hunger in between milk feedings by consuming the starter grains that are offered to them. Increasing the quantity of milk being fed to satisfy hunger will only delay that starter intake. At weaning, calves should be consuming at least three pounds of grain daily. If calves are not consuming adequate amounts of starter, it is not a good practice to remove all liquid feed, as it is not healthy to starve a calf onto grain. Keeping daily feed logs is an excellent management tool to help monitor grain intakes, refusals, as well as any sudden decrease in grain intake.

Gelsinger et al., 2016.  J. Dairy Sci. 99:6206-6214.

What qualifies as a "good" calf starter?

In visiting numerous farms, inspecting the different calf grains seems to always result in something new. The following picture is just a taste of the variation in calf starters that are being fed.

Photo credit Cassie Yost

As shown, calf starters vary in texture, moisture, palatability, nutritional content, and smell. In addition, the cost is also something that will vary from starter to starter. Some farmers choose to mix and grind their own starters, often resulting in one with unknown nutritional content. While this may be a cheaper route, it may not produce the most favorable of calf starters. These starters tend to be the finely ground starters as shown in the photo. Some starters visibly contain more molasses than others. While molasses is a good binding agent, too much molasses content can create problems such as palatability issues, especially in cold weather, decreased intakes, and even an increase in scours. In addition, large amounts of molasses can result in soft pellets that break up with subsequent handling of the feed (Bateman et al, 2009). Other starters shown appear too dry which could lead to poor intakes and the possibility of breaking into too many fines. With so many starters on the market and the variables associated with each one, choosing one can be a hard decision to make.

In reviewing some of the latest research on calf starters, the biggest issues seem to be grain processing, the presence of fines, and the addition of forages. One of the biggest concerns is the presence of fines in calf starters. In a research study conducted in 2018 it was concluded that the lower average daily gain (ADG) seen in calves offered coarse grain with a mash supplement (CM) was due to fine particle sized starter diets leading to poor acceptability, low intake, and decreased weight gain in calves compared with the large particle sized starter diets (Omidi-Mirzaei et al, 2018). This reiterates the findings from an additional study where identical diets were fed but one diet intentionally contained fines. In this study, calf intake was reduced by 11% and ADG was reduced by 6% versus calves fed 100% coarse textured starter with few small particles (Bateman et al, 2009). An additional study conducted by Omidi-Mirzaei et al. (2018) cautioned that consumption of fine particle size diets has been considered a risk factor for the proper rumen function and feed intake in calves.

A second concept that is researched heavily in calves is the addition of supplemented forages in the calf diet. One reason for supplementing forages is to provide calves eating a finely ground starter with additional roughage to prevent ruminal acidosis. Feeding starters containing fine particles in mash form or processed in a pelleted form has triggered rapid ruminal acid production from fermentation of carbohydrates, reduced ruminal pH, and impaired rumen epithelial development (Omidi-Mirzaei et al, 2018). How rapidly carbohydrates are digested affects a calf's rumen pH, and particle size is directly correlated to this. A previous study found lower ruminal pH in calves consuming a pelleted starter feed than calves consuming a texturized starter feed; however, a texturized starter feed had similar benefits on rumen pH as a pelleted starter feed supplemented with straw (Omidi-Mirzaei et al, 2018). This study along with others concluded that the physical form of starter feed influences rumen fermentation and pH. And feeding calves with finely-ground starter feed high in rapidly fermentable carbohydrates reduces ruminal pH and starter feed intake. 

In addition to physical characteristics of calf starters, there are other factors that help determine which is the most ideal calf starter to feed: feed presentation, eating habits, storage, and economics. Ultimately, the health and performance of your calves are the most important factors that should determine which starter to feed. If the growth of your calves is not reaching recommended benchmarks, perhaps the starter that is being fed is playing a larger role than you think. Take a critical look at starter characteristics, eating habits, and overall performance. Don’t be afraid to shop around when it comes to calf starters, and don’t overlook its importance in the growth and development of your calves.

References:

Bateman Ii, H. G., Hill, T. M., Aldrich, J. M., & Schlotterbeck, R. L. (2009). Effects of corn processing, particle size, and diet form on performance of calves in bedded pens. Journal of dairy science, 92(2), 782-789.

Omidi-Mirzaei, H., Azarfar, A., Mirzaei, M., Kiani, A., & Ghaffari, M. H. (2018). Effects of forage source and forage particle size as a free-choice provision on growth performance, rumen fermentation, and behavior of dairy calves fed texturized starters. Journal of dairy science, 101(5), 4143-4157.

Omidi-Mirzaei, H., Azarfar, A., Kiani, A., Mirzaei, M., & Ghaffari, M. H. (2018). Interaction between the physical forms of starter and forage source on growth performance and blood metabolites of Holstein dairy calves. Journal of dairy science, 101(7), 6074-6084.