Dairy farmers who rely on hay crops such as grass haylage often have a difficult time getting consistent value and performance out of those forages. For many dairies, haylage is included in the diet regardless of the quality and at varying levels if and when it’s available. For many dairy farmers, hay crops are, more often than not, a bigger hindrance than they are a help. Especially when forage quality is low, hay crop forages end up increasing total feed costs for the dairy.
High quality hay crops – meaning higher crude protein and lower fiber – allow a reduction in purchased grains and by-products. Most grasses and legumes in the early-vegetative stage not only have higher total protein but a more rumen-degradable protein that improves rumen bacterial levels and fermentation. Fiber is less lignified, which allows for more of the plant to be fermented and digested. As forages mature, which includes flowering or going to seed, the plant’s protein disappears and the fiber levels rise and become less digestible.
Due to the difficulties involved with securing high-quality hay crops, corn silage has become the forage of choice for most dairy farms today, and rightfully so. Corn silage brings with it the nutritional attributes of fiber and energy in a single package and produces more calories per acre than any other forage. However, corn silage is limited to about 25 pounds of dry matter in most high-producing rations due to protein limitations. In order to help keep the milk components up and the grain bill down, dairy farmers still need to feed hay crop forages. The challenge, of course, is feeding the optimal quality forage that maximizes net milk income.
To illustrate the profound differences in feeding costs to support a constant level of milk production, I offered three different haylages of varying quality in a hypothetical but realistic dairy cow diet. I used a popular diet-balancing computer program to analyze the diet. This ration is designed to support 75 pounds of milk for a Holstein cow weighing about 1,400 pounds. The butterfat and milk protein percentages are set at 3.75 and 3.10 respectively. The daytime temperature is 40 degrees Fahrenheit, which is what we’d expect for New England in late winter/early spring. Daily feed intake (dry matter basis) for this cow is predicted to be 48 pounds.
The three haylage crops are taken from the standard feeds library of the ration balancer. They are intended to represent a high-, medium- and low-quality haylage that can be found on nearly every dairy farm at any time of the year.
- Haylage A tests 16 percent Crude Protein and 55 percent NDF (neutral detergent fiber)
- Haylage B tests 10 percent Crude Protein and 67 percent NDF
- Haylage C tests 7 percent Crude Protein and 72 percent NDF
The moisture level for these three haylages is 60 percent and it’s assumed that these forages have fermented properly and have no serious quality issues related to ensiling and bunker/silo management.
The corn silage used in the diet is typical with 7.8 percent crude protein, 45 percent NDF, 34 percent starch and, again, considered to have a proper fermentation profile with a moisture level of 60 percent. No effort is being made here to distinguish between processed or unprocessed silage or starch and fiber digestibility as it is not considered relevant to the predicted milk production.
Grain and protein supplementation utilize the typical feedstuffs and commodity by-products available in New England including corn meal, distillers grains, wheat midds, soybean meal, canola meal, beet pulp, along with both rumen-protected fat and animal fat. In an effort to keep the diet simple, vitamin and mineral supplementation is kept to basic minimums with no attempt to fortify the diet with yeast, probiotics or toxin binders.
In diet 1, with all three haylages offered for inclusion in the ration at the same price, the ration optimizer took only haylage A, ignoring haylage B and C. The diet on a dry matter basis is as follows:
- Corn silage; 14.2 pounds
- Haylage; 16 percent, 14.0 pounds
- Grain mix; 19.8 pounds
Note that the dry matter levels of corn silage and haylage are nearly the same, indicating that this haylage offers a high level of nutrition. Grain inclusion came in under 20 pounds with the crude protein level of the grain mix being 22.4 percent. The cost (on a raw ingredient basis – FOB mill) for this mix is $3.08 per cow per day. Beet pulp was offered in this diet at a 5-pound maximum both as a source of soluble fiber and as an alternative to corn silage. The optimizer ignored the beet pulp, taking only corn silage in diet 1.
In diet 2, the 16 percent haylage is left out, (meaning the dairy doesn’t have any) leaving haylages B and C. The diet, again formulated to support 75 pounds of milk, is as follows:
- Corn silage; 21 pounds
- Haylage; 10 percent, 5.7 pounds
- Grain mix; 21.3 pounds
In diet 2, the corn silage is optimized at the maximum level allowed for in this exercise (70 pounds as fed) and the haylage is greatly reduced due to its nutrient limitations. In this diet, the dairy farmer must feed more grain and the grain mix has now climbed to a 25.5 percent crude protein with a cost of about $3.50 per cow per day. Beet pulp is optimized into the grain mix at 2 pounds.
In diet 3, only haylage C is available. The optimizer all but ignores haylage C, looking for all the corn silage and beet pulp it can have, taking the full 5 pounds of beet pulp allowed. The diet is as follows:
- Corn silage; 21 pounds
- Haylage; 7 percent, 3.0 pounds
- Grain mix; 24 pounds
In diet 3, the total cost of grain fed to the cow has risen to $3.85 per cow per day even though the crude protein has dropped back to about 23 pounds.
Across the three diets with the three different quality hay crops, the cost of the grain added to the ration increased over 80 cents per cow per day to cover for the decreased quality of the haylages B and C. Even as more corn silage and beet pulp are brought into the ration for energy needs, they cannot meet necessary protein needs to support 75 pounds of milk production.
It’s clear that the haylage testing 16 percent crude protein supplied energy, protein and soluble fiber in place of purchased commodities, allowing for a lower purchased grain cost. All three diets are able to support 75 pounds of milk production but when high-quality haylage is not available, the cost of the purchased feeds necessary to produce 75 pounds of milk increases significantly. Hay crop forages definitely have a place in high-producing dairy herds; however, dairy farmers must focus on high quality. Anything less will cost more money to make the milk you’d like your cows to produce.
Cover Photo by dial-a-view/istockphoto.com