Nutritionists work to guarantee dairy cows get the proper nutrients to stay healthy and productive. To do this, they identify each animal’s nutrient requirements and feed them a ration that meets those needs.
Dairy cattle rations typically consist of fibrous feeds such as corn silage, legumes and grasses combined with grain and supplements. This combination provides each cow with the necessary nutrients to produce milk.
Contents
Protein
The cow’s mammary gland requires a variety of nutrients to produce milk. These include protein (amino acids), carbohydrates, fats and vitamins.
Carbohydrates make up the bulk of dairy cows’ diets, accounting for up to 70% of their caloric intake. These can range from simple sugars to complex polysaccharides.
Dietary carbohydrates are divided into fractions based on chemical characteristics and nutritional benefits (see Plant Carbohydrate Fractions). Cellulose, for instance, is a 1,4-linked glucose unit.
Carbohydrates
Carbohydrates are an integral part of dairy cattle nutrition. Not only do they provide energy to the cow, but also essential nutrients like fiber and vitamins which support good health.
Carbohydrates are essential for digestion and growth. The healthiest carbohydrates are unprocessed or minimally processed starches such as potatoes and yams, vegetables, fruits, and beans.
The worst carbohydrates for weight gain and hormone imbalance are highly processed carbs like white bread, pasta, pastries and sodas. These can cause sudden spikes in blood sugar levels which may lead to weight gain, hormonal imbalance and diabetes.
Typically, 45 to 65 percent of calories should come from carbohydrates. This recommendation is based on a 2,000 calorie diet, or approximately 225 to 325 grams of carbohydrate per day.
Fat
Dairy cows require a lot of energy for both milk production and maintenance. A lactating dairy cow weighing 1,400 pounds requires roughly 33 Mcal/day in net energy for lactation (NEL).
Dietary fat is an essential energy source that can be added to the diet to meet energy requirements. However, it should not exceed 7% of total daily DM for maximum effectiveness.
It is essential to recognize dietary fat as an energy resource that should be utilized responsibly and in moderation. Excess fat may lead to decreased feed intake, potentially negating any beneficial effects from increasing energy density in a ration.
Fiber
Fiber is an essential element of dairy cattle nutrition, helping to support healthy rumen function and cow wellbeing. However, the effectiveness of dietary fibre depends on its type, quality and particle size.
Dairy cow diets that lack fiber can lead to decreased milk fat percentage, reduced feed conversion ratio and hoof health issues. To combat these effects, increasing fiber intake through long-stemmed forages that are finely ground or chopped into silage will encourage chewing and increase salivary secretion.
Dietary carbohydrates refer to a wide variety of compounds, from simple sugars to complex polysaccharides found in plants’ cell walls. These carbohydrate fractions are classified according to chemical measures and nutritional effects (see Plant Carbohydrate Fractions).
Vitamins
Vitamins are organic compounds that act as coenzymes (non-protein parts of enzymes). They aid in the stimulation of cellular chemical reactions and should be included as part of a balanced diet to maintain good health.
Plant and animal foods as well as dietary supplements contain these essential amino acids, which must be consumed in small amounts to stay healthy.
Milk-producing dairy cattle require adequate amounts of vitamins A, D, and E for growth and udder health. Supplementing rumen-protected B-vitamins like biotin, niacin, and choline may increase milk production.
Trace minerals such as copper, iron, magnesium, manganese, selenium and zinc are necessary in minute amounts to support metalloenzymes’ biological activities. They also influence acid-base balance, oxidation status and immune function of animals.
