Getting the Most From Your Grazing System
The question often comes up as to whether a dairy business would be better off financially if it grazed the milking herd on high-quality pastures and fed less purchased grains.
In recent years, the cost of purchased feeds - grains and commodity byproducts - has increased sharply, cutting into the profit margins of many dairy farms. Conventional dairy farming has had to focus on increasing size and economies of scale to stay in business. With the cost of feed being the single largest expense for a dairy operation, the quest for an alternative feeding program that lowers the net feed cost is something that nearly every dairy farmer is confronted with at some time in their career. More often than not, many dairy farmers find themselves backed into a corner with rising feed debt, and the decision to pasture the herd is more about a last-ditch effort to stay in business.
Dairy farmers should not look at grazing their herds as an inferior option. Dairies that graze their herds tend to be smaller in size due to the amount of real estate needed to pasture cows. The decision to graze a dairy herd can also involve "lifestyle" preferences. Planned and managed correctly, cows on pasture can provide acceptable financial returns in areas of the country that have the land and the climate to support productive pastures.
For all dairy farms, revenue from milk sales is what keeps the business afloat, and there's no question that feeding high levels of grains and commodities has pushed our national milk production to historic heights. At the end of the day, though, the question must be asked if switching a dairy herd to a grazing and/or high-forage feeding system might possibly increase the net income over feed cost.
At the heart of a successful grazing system is maintaining a very high-quality forage throughout the year. This may also involve mechanical harvesting to store forage so it will be available during the winter months when pastures are not available.
Whether feeding cows in confinement systems or allowing them to graze on pastures, the ultimate goal is for the cows to produce milk. Fluctuations in forage quality will quickly affect milk production. We've all seen it happen.
When forage quality is good, we see an immediate response in the milk tank; when the quality declines, we also see an immediate response in the milk tank.
A major influencing factor for milk production is the amount of feed the cow consumes every day: dry matter intake. If a dairy farmer is considering ways to reduce the amount of grain and commodities, then the alternative must be a higher-forage diet. The quality of forage, meaning the digestibility of that forage, makes all the difference in the world as to whether a farm can be successful with a grazing system. Dairy farmers who are successful at maintaining high milk yield with grazing systems tend to be successful in effectively managing both nutrition and the pasture environment.
The first and most important component of a grazing system is a pasture management strategy that maximizes the amount and quality of forage cows can consume from the pasture. Key management factors include: selection of forage species that are adapted for the soils and climate of the farm, optimal soil fertility to maintain forage growth through the grazing season, management of forage growth by manipulating stocking density, selective mechanical harvesting, and strategic use of grain and forage supplements.
Recognizing that purchased feedstuffs are being removed from the milking cow diet, the second management issue is provision of supplemental energy and protein to optimize milk production. Even the highest-quality pastures will not provide adequate energy to cows of high genetic potential. Generally, some grain must be left in the diet. If supplemental energy is not provided to high-producing cows, milk production, body condition and reproductive performance will diminish.
A common challenge faced by farmers who are switching to grazing systems is figuring out how much supplemental grain should be fed. Successful pasture management programs must include a grain feeding strategy where adequate supplemental energy is fed to complement, not replace, the supply and quality of pasture. As the forage quality of a pasture diminishes during a season, additional grain supplementation is necessary to maintain milk production.
Too much grain will reduce the amount of forage consumed and defeat the purpose of the grazing program. Then again, too little grain may force cows to possibly overgraze a pasture. It becomes critical to recognize that stocking density of pasture paddocks will have to be adjusted during the course of a season based on forage quality and how the pastures are holding up. In some years, pastures are likely to get ahead of the cows due to low stocking density and/or advantageous climate and growing conditions. Some mechanical harvesting (bales or haylage) may be necessary to keep from losing forage quality.
The foundation of dairy cow nutrition centers on the health of the rumen and the amount of microbial protein that the rumen can produce. Whether cows are on conventional grain diets or high-forage/pasture diets, the synthesis of rumen microbial protein dictates how much milk a cow can produce. While it's easy to stress the need for high-quality forage, there is a catch-22 involved here: effective fiber diminishes with highly digestible forages. Lowering dietary effective fiber will have a deleterious effect on rumen microbial synthesis. Just when you think the pastures are the best they've ever been, you see a drop in butterfat and milk production because the rumen is having problems. Maximizing and sustaining high milk production on pastures is both an art and a science.
In many parts of the U.S., and particularly in the Northeast, opportunities abound for grazing dairy herds and successful dairy farming operations. While the commercial dairy industry has focused on high milk production with the use of grains and commodity byproducts, we must remember that a cow is still an herbivore that was created to survive primarily on herbaceous plant material. With proper management, dairy farmers who choose to graze their cows on pastures and focus on high-quality forages can generate impressively high profits per cow.
The author is a dairy nutritional consultant and works for Central Connecticut Cooperative Farmers Association in Manchester, Conn.