While we all know that milk is an important part of our nutritional health, you might not be aware of all the work and science that goes into ensuring dairy cows have the proper nutrition to produce that delicious, healthy milk.
I have had several opportunities, through my job with the Maine Dairy & Nutrition Council and Maine Dairy Promotion Board, to talk to the public about dairy farming in Maine. I like to throw out interesting facts such as Maine’s dairy farmers protect 700,000 acres of open farmland and small woodlands. Or Maine’s dairy farms range in size from 8 cows to 3,400 cows. And that a dairy cow can produce upwards of 100 pounds of milk per day (the average is 70 pounds). This then leads to the fact that a dairy cow can eat 100 pounds of feed a day. At this point, peoples’ eyes go wide, and you can see them thinking about all the resources that go into feeding that cow. However, many people are unaware that much of a dairy cow’s diet is made up of byproducts – byproducts of human consumption. Those that are not byproducts, like grass in all its forms of hay, haylage, balage, silage, can’t be digested by humans, and Maine is pretty good at growing grass. When corn is chopped on the farm for cows, the ENTIRE plant is chopped – they don’t just eat the kernels of corn.
Other byproducts that Maine dairy farmers rely on include the following:
- Brewer’s grains from the growing craft beer in Maine.
- Distiller’s grains, usually corn-based, is a byproduct of ethanol or alcohol.
- Soybean meal is a byproduct when soybean oil is extracted to use in products like margarine, mayonnaise and salad dressings.
- Okara – a byproduct of tofu.
- Canola meal – a byproduct of canola oil.
- Wheat middlings and red dog, both of which are byproducts of wheat flour, are used to make pelleted feeds for dairy cows.
Emilee is a dairy specialist for Gold Star feed and grain. She allowed me to tag along with her when she made one of her weekly visits to Mark Sawyer’s farm in Newport recently. My head was spinning with so much information by the end of the visit. So many factors are considered when planning dinner for a dairy cow:
- Weather – how cold is it? How much energy will the cows expend to keep warm?
- What life stage are the cows at – calf, puberty, heifer, dry cow (during the vacation period just before she has her calf), pregnant, fresh (just had her calf), nearing the dry off period?
- How much milk is she producing?
- What is the farmer’s goal for his cows to be producing (pounds of milk per day)?
- What forages grown on the farm does the farmer have available? What is the quality of those forages?
- What is the cost of grain at this time? Soy? Corn?
The farm separates cows into groups depending on age/life stage and how much milk they produce, and then each group receives its own special diet that is determined through Emilee’s observation and computer analysis.
On this particular visit, which was coming on the tail end of the coldest stretch of winter, Emilee was concerned about the level of energy in the cows’ diet. On her last visit, she said, the cows seemed “almost lackadaisical” as she walked through the barn. “I really cranked up the energy,” she said. On this visit, she walked through the herd and was pleased with the amount of movement and alertness of the cows, and their body condition was in top form. But because she had upped the energy, that made the grain richer, and she was also concerned that the cows’ manure might become too loose, which would mean they weren’t absorbing the nutrients as they should, so part of her job also includes inspecting cow patties. In this case, they looked good. As the weather warms, she will continue to change the cows’ diet accordingly.
Mark and Emilee discussed how his cows were doing. With extreme cold weather, a cow will often drop off in milk production because the energy she consumes is going toward keeping her warm, not making milk.
“Most herds are down 2 to 5 pounds” per cow, Emilee said, but Mark’s cows were averaging nearly 2.5 lbs more than just two weeks earlier. That was especially impressive because he didn’t have many “fresh” cows, which produce a higher amount than say a cow that is nearing her dry off period.
“And your components are excellent,” Emilee said. Components are the balance of protein and fat in milk. If butterfat is too high, the farmer is concerned that his cows are ketotic because the cows’ energy demands are exceeding their energy intake, and the fat is coming out in the milk. If the fat is lower than the protein, then a cow can be acidotic, which can make her sick to her stomach and even cause hoof trouble because there will be an increase of blood flow to the hoof, causing a growth spurt, which can then lead to abscess or ulcers.
As they talked about the cows’ performance, Mark told Emilee he had a surplus of haylage he had produced on his farm the previous summer and he was hoping to work more into the cows’ diets. Emilee suggested that they might be able to add as much as 10lbs of haylage per cow to the cows’ total mixed ration (TMR) or daily meal plan.
Mark was happy, “That’s nearly 2,000 pounds. That’s a lot of haylage.”
When Emilee is preparing the meal plan for a farmer’s cows, she always takes into account the homegrown forage that is available. When a new bunker (where forages are stored
after harvesting) is opened, she will test the forage every week until she gets a baseline reading. She then tests it every month. She is looking for water content because when weight of feed is determined, she only deals with dry matter (the water is discounted because the nutrition is not in the water). She is also looking for things like carbohydrates, protein, amino acids, fiber and fat. When she considers feed sources off the farm, she always starts locally. Gold Star buys as much corn meal from Maine crop farms as possible. Barley is not a byproduct, but Gold Star is able to buy 100 percent from farms in Aroostook County.
“It’s good for the state, good for the farmers, and good for us because the cost of trucking is so high,” Emilee said.
A cow’s diet and nutrition is under constant monitoring because a dairy cow is like an ultra-marathoner, Emilee says. “They are running a marathon every day.” A cow’s dietary needs are like something out of Women’s Health Magazine – focused on terms like energy, protein, carbohydrates, amino acids and fatty acids. With new research, diet recommendations are also changing. Nutritionists now look to amino acids – the building blocks of protein – rather than high protein sources. “The protein and energy needs to match up. If she gets too much protein and not enough energy, she can’t digest it, and she will secrete it in her urine or milk.”
This means Emilee relies less on high-protein sources like soybean meal, and looks to maximize the nutritional benefit of forages. New knowledge about bovine nutrition has also led to farmers using less nitrogen and phosphorous on their fields.
A bovine’s nutrition is important from the day she is born. Calves need to receive colostrum quickly to build up their immune system. From there, their diet has to be monitored so they will grow at a healthy rate. “We want them to grow tall and strong,” Emilee said. The rest of her life is a balancing act, making sure she can support a calf growing inside of her, while keeping herself in tip-top shape and producing nearly 10 gallons of milk a day (after her first calf – a cow must have a calf before she can produce milk). At the Sawyer Farm, Mark also has several older cows, some as old as 13, which adds another consideration when planning a diet.