Nutrition for dairy cows is being fine-tuned daily – the result of an increasing need for improved feeding efficiencies as milk prices remain low and other production costs increase. There’s also the growing pressure of environmental regulations focusing on nutrient management coming from a dairy’s waste stream.
As dairy farmers seek to increase milk production per cow, the diets they feed their cows must be formulated to deliver just the right amount of nutrition without over-feeding or wasting nutrients. Feeding cows is the largest expense on dairy farms and every feedstuff offered in the diet must be evaluated for the energy, protein, vitamins and minerals it contains to satisfy milk production in mature cows or growth rates in young stock.
Formulating dairy diets was once a fairly straightforward procedure as only a handful of nutritional constraints such as crude protein, crude fiber and ash were quantifiable. The complex inner workings of the rumen were poorly understood as were the requirements for protein and energy. In less than a century, though, dairy scientists and ruminant biologists have unlocked many of the secrets of a cow’s digestive system along with the metabolic requirements for macro and micro nutrients.
Today, the term “crude protein” is no longer relevant in formulating milk cow diets. It’s now recognized that cows do not have protein requirements, per se, but requirements for specific amino acids that are contained within the proteins.
A similar development has occurred for crude fiber. Fiber is now partitioned into various fractions with differing rates of digestibility in the rumen, depending on their molecular construction. Rumen microbes use certain forms of nitrogen – again coming from different amino acids as well as nonprotein sources – whereas other amino acids are necessary for metabolic needs and milk composition. Some recent research has shown there are multiple pools of fermentation in the digestion process that affect what kinds of protein and fiber are used in the diet.
Various universities, agricultural institutions, research facilities and private companies have spent millions of dollars to understand the rumen digestive process, developing products that improve rumen health, microbial population and optimizing the fermentation process to cash in on the billion-dollar dairy feed industry to make the modern dairy cow more productive.
Historically, the dairy industry has embraced and implemented new technologies that have the potential to improve milk production per cow or overall farm gross revenue – even while profitability per cow decreases. Unfortunately for dairy farmers worldwide, the implementation of new and advanced nutrition technologies, while making dairy farming increasingly more efficient and environmentally sustainable, has served to make milk and feed prices volatile and profit margins smaller, resulting in the pursuit of even higher production efficiencies.
None of this would be possible if not for the use of computers and the ability to process data quickly. Computer software has been specifically designed to formulate diets from an array of constraints and pricing points designed to model rumen function and predict milk production scenarios for a combination of feedstuffs and environmental conditions such as weather and housing. Today, dairy farmers rely on nutrition software that can quickly predict milk production through “least cost” optimization programs that use linear programming algorithms.
Ration balancing programs allow dairy farms to formulate in a matter of minutes various diets for different levels of milk production within the herd showing potential revenue and income-over-feed cost margins. Herds can be grouped into as many production groups as there’s room for, as well as formulating diets for dry cow, transition cows and heifers. The age of computers doesn’t stop with ration modeling. In the milking parlor, computers can measure milk flow in real time. A cow wearing a transponder can walk into a robotic milking unit and be fed a precise amount of feed for the milk she’s producing while the robot’s computer analyzes the milk for quality and components.
With feed costs making up more than 50 percent of many dairy farms’ expenses, monitoring daily feed usage and inventories is critical to dairy profitability. Feed wagons and trucks with vertical and horizontal mixers have scales that interface with computers that keep track of feed usage, making sure cows are getting the diet the nutritionist says they should and feed isn’t being wasted and nutrients are being over- or underfed.
The particle separator box developed by Penn State University is a handy tool that should be used frequently to evaluate particle length of the mixes being fed to the cows. The particle separator gives a very accurate portrayal of how well the total mixed ration is being undermixed, overmixed or mixed correctly. Even if the feeder on the dairy is mixing ingredients correctly, mixing time may be reducing forage length, which can have a detrimental effect on rumen function if particle length is too short.
Since forage is the foundation of all dairy cow diets, high forage quality is critical to maximize milk production. In the last two decades, forage testing laboratories have provided more services to analyze fiber fractions and digestibilities, enabling dairy farmers and nutritionists to make informed decisions about the forage they produce or purchase elsewhere. More recently, labs have begun offering assays of starch digestibility as well, since university research has determined there are multiple pools of starch digestion in the rumen as well as fiber digestion.
Between improved mixing and feeding equipment technology, competent ruminant nutritionists, computerized ration formulation and diet modeling, along with the services from private and commercial laboratories that provide extensive information on feed quality, today’s commercial dairy farmers should never wonder how to maximize or improve milk production.