Creating the optimal feed ration is essential to maximize milk production in dairy herds while maintaining cow health. The base ingredients of a total mixed ration (TMR) typically include forages like hay, haylage, silage as well as grains like corn, soybean meal, barley, wheat middlings, or distillers’ grains. When formulating rations, key nutrients to focus on are energy, protein, fiber, vitamins, and minerals.
The forage-to-grain ratio in the TMR can be adjusted to fine tune energy levels. Higher fiber forages like alfalfa, oat hay and wheat straw provide cows bulk to ruminate and maintain rumen health while higher starch grains like shelled corn or barley pack more calories into every bite. Finding the right balance is crucial, as too little fiber can cause subacute ruminal acidosis while insufficient energy restricts milk synthesis. Fiber should make up at least 25-30% of the dry matter in lactation rations.
Protein requirements also increase dramatically for high producing cows. Both rumen degradable protein to feed the rumen microbes and bypass protein that resists breakdown in the rumen need to be provided. Common protein supplements include soybean meal, canola meal, cottonseed meal, and distillers dried grains with solubles. Total crude protein should range from 16 to 18% while rumen undegradable protein should be around 35% of total protein.
Bypass Nutrients
While a properly balanced TMR supplies most required nutrients, additional supplementation with rumen protected “bypass” nutrients can further enhance production. Since the rumen microbes break down and utilize some nutrients like fats or amino acids before they are absorbed, chemically treated supplements are designed to bypass initial microbial metabolism.
The experts at Energy Feeds International say that bypass fats are an important bypass nutrient for early lactation cows. Adding 3-4% dietary fat from sources like prilled hydrogenated fats, calcium salts of long-chain fatty acids boosts energy density without negatively impacting fiber digestion. Bypassing lipolysis in the rumen, these fats are efficiently absorbed in the small intestine. Other bypass options include choline chloride, amino acids like lysine, methionine, histidine and glucogenic precursors like propylene glycol. Though more expensive, strategic supplementation delivers nutrients directly to the cow.
Consistency is Key
Cows are remarkably sensitive to fluctuations in ration ingredients or nutritional composition. Changes as small as 5% in nutrient levels can significantly affect dry matter intake, milk yield, milk fat and protein percentages beyond impacting production levels, cycles of overfeeding and underfeeding, and increase health issues like laminitis, acidosis, and liver abscesses.
To limit variability between rations, they should be mixed the same way every time using consistent ingredients from known sources in the same proportions. Forages and other low moisture feeds must be analyzed routinely to account for changes in harvest and storage conditions. Any necessary adjustments to the ration should be made incrementally over days or weeks to allow the rumen microbiome to adapt.
Other Considerations
Besides nutritional strategies, environmental and management factors also influence milk production. Cow comfort affects time spent feeding versus lying down, so adequate bunk space of at least 2 feet per cow and soft, dry bedding should be ensured.
Transition cow management deserves special focus, as this period has an outsized influence on subsequent lactation performance. Gradually adapting rations pre-calving, providing propylene glycol, ensuring proper pre and post calving pen sanitation, aggressively monitoring and treating metabolic disorders, and addressing any health issues quickly sets cows up for success.
Conclusion
While genetics supply the baseline production capacity, nutrition unlocks a dairy cow’s milk making potential. Following these nutritional best practices allows modern Holsteins to produce over thirty liters of high-quality milk each day. Fine tuning the diet to precision match nutrient requirements minimizes health risks while maximizing profits.
