– Dr. Steven C. Loerch, OSU Animal Sciences Department, OARDC
Meeting the nutritional needs of beef cows during the winter is a costly proposition. On average, it costs about $350 a year to maintain a cow. Of these annual costs, approximately two-thirds ($230) is cost of feed. If you feed hay valued at $60/ton for five months during the winter, this cost is approximately $160 (or $1.05/cow/day). Reducing winter feed costs provides the greatest opportunity to improve profits for beef producers. This paper will outline factors affecting cow nutrient requirements and winter feeding systems for beef cows that reduce annual feed costs for the cow herd.
Cow nutrient requirements must be met for optimum production and reproductive performance. These requirements are dependent on the size (body weight) of the cow, her milk production potential, her stage of production, and the environment (temperature, wind and wet hair coat). In Ohio and surrounding regions, meeting requirements for calories (energy) is the most costly and important nutrient. Every 100 lb increase in average cow body wt increases net energy requirements by about 6%. Milk production potential plays a bigger role in energy requirements, but this only is of major importance during the first three months of lactation. Cows with superior milking ability require 25% more energy than those with average milking ability. Stage of production plays a major role in energy requirements. For example, we will consider a 1200 lb beef cow with average milking ability (16 lb/d). This cow requires 16.3 mega calories of net energy per day for the first three months post calving, 12.5 mega calories per day from three months post-calving to weaning, 8.8 mega calories per day from weaning until 60 days before calving, and 11 mega calories per day during the last 60 days of pregnancy. If these requirements are not met, calf survival, weaning weights and the cows’ ability to rebreed are compromised. Based on these numbers, it is obvious that there is up to a 2-fold change in energy requirements dependent on stage of production. This is the main rationale for calving cows in the spring. Spring calving matches the highest nutrient requirements of the cow with cheap, plentiful, high quality, cow-harvested forage. Having a short, defined calving season is also important because cows are then all in the same stage of production, allowing their nutrient requirements to be met. Over feeding cows wastes money on feed and under feeding cows reduces production and reproductive performance. Both should be avoided. Spring calving also means that costly winter feeds are being used when nutrient requirements are the lowest. Environmental effects are most significant in the winter. For a cow with little wind and a dry hair coat, energy requirements go up by 1% for every 1 degree drop in temperature below 32 degrees. This means if it is 0 degrees, a cow requires 32% more energy than if it were 32 degrees.
Winter Feeding Strategies – I will focus this discussion on meeting energy requirements of non-lactating, pregnant cows. Adequate mineral supplementation is important every day of the year and requirements can be met by providing a quality mineral mix free choice. Non-lactating, pregnant cows only require about 8% protein and meeting this protein requirement is rarely a problem when cool-season forages are fed.
1. Forage testing. To me, there are two main reasons for forage testing. First, it allows you to predict deficiencies in energy and protein for a particular stage of cow production. Cows can’t eat as much poor quality forage and it is lower in net energy for maintenance (NEm). This is a double whammy. Hay that is more than 70% NDF will not meet energy needs the last eight weeks of gestation or during early lactation. This causes all kinds of production problems (loss of Body Condition Score, more dystocia, lower milk production, and delayed return to estrous and difficulty rebreeding). All of these are magnified in 1st and 2nd calf heifers. Protein is probably not as big an issue for our forages, although some supplementation may be necessary during early lactation if you have good milking cows and hay is less than 10% protein.
This brings me to the second reason for forage testing: to help in the decision of what hay to feed when. Perhaps this is the simplest and most effective step a producer can take. Great efficiency can be achieved just by matching forage quality with nutritional needs of the cow. For March/April calving cows, the poorest quality hay should be fed first during the winter. After weaning, the cow’s requirements are the lowest. When grazing can no longer be accomplished in the fall, then feed your poorest quality hay. During late January, February and March (before calving) energy requirements are on the rise. This is also when cold weather taxes the cow’s energy status. Hay quality factors and the cow’s energy requirements should dictate what hay gets fed when. The best hay should be saved for late gestation and early lactation (before spring pasture turn-out). Sorting cows into groups based on their nutritional needs is another good way to save supplemental feed costs. If half of my cows are in good condition, there is no point in wasting supplement on them just to meet energy needs of my thin cows. You can save supplement costs by pulling out thin cows and feeding them with your replacement heifers. Cows will usually start showing the effects of poor quality forage in late January and February. Keep a sharp eye on body condition score during these last eight weeks before calving season. Management intervention to maintain cow body condition during this time is more effective and profitable than letting cows get thin and then trying to recover later.
2. Hay feeding. Feeding hay in the winter is an expensive habit. A cow will generally use 35 to 40 lbs of hay per day. They won’t eat quite this much, but when you consider storage and feeding losses, this is a reasonable estimate (maybe even an underestimate). Hay at $40/ton results in feed cost per cow of $.70/day. If hay is $60/ton this is $1.05/day; $80/ton is $1.40/day. Typical cost estimates for grazing (cow harvested forage) are $.25 – .30/day. Feeding hay instead of using grazing alternatives may be a dollar per cow per day right out of your pocket.
3. Extended pasture grazing. We have completed three years of research on extended grazing at the Coshocton Branch of OARDC. There were 31 cows per year grazing the stockpiled pasture. We used 34 acres of stockpiled fescue. There were six fenced paddocks in the pastures ranging in size from 5 to 8 acres. Pastures were fertilized on August 1 with ammonium nitrate to provide 80 lbs of N per acre. This fertilizer cost was about $20/acre. Pastures were set aside and not grazed from August 1 until the trial began in late October. Cows spent about 18 days in each paddock before being rotated to the next paddock. Forage was depleted by mid February. Emergency feed during snow cover was limit-fed whole shelled corn (11 lb/day), supplement (1.7 lb/day), and hay (3 lb/day). After February 16, when pasture was depleted, cows were limit-fed a corn-based diet until spring pasture turnout in April. Cows gained 100 lbs during the 112 day trial and held their body condition score (Table 1). Part of this weight gain would have come from fetal development because end weight was made three weeks before the calving season began. This pasture system supported a cow on 1.1 acres for 112 days (Table 2). There was an average of 20 days/year when supplemental feed was needed due to snow and ice cover. Based on pasture rental, fertilizer and harvested feed costs, this system fed a cow for $.55/day. The breakeven value for feeding hay all winter (instead of stockpiling forage) was $31/ton. This means if hay costs more than $31/ton, you could feed cows cheaper with stockpiled forage. If hay is $80/ton, stockpiled forage saves you $1/cow/day. It is important to point out that deferring 1.1 acres/cow for winter grazing means this land can not be used for grazing in late summer and the fall. Adequate pasture land is necessary to carry your herd through the summer grazing season and allow 1.1 acres/cow to be deferred for winter grazing. Fiber content (NDF) of stockpiled forage increased during the winter from 60% to over 70% due to leaf shatter and leaching of soluble sugars. Protein content averaged about 11% and did not change significantly during the winter.
4. Limit-feeding corn (or byproducts like soyhulls). Corn grain is the least expensive harvested feed per unit of digestible energy available to producers in Ohio. The most common feed used for wintering cows is hay. This is despite the fact that hay costs 50 to 100% more than corn, per unit of energy. Corn priced at $3.00/bu is worth $107/ton. Because hay has only about half the energy value as corn grain, the break-even price for hay on an energy basis would be approximately $54/ton. In many situations it is economically advantageous to use corn rather than hay to meet the energy requirements of cows.
Cows, and all other animals, require a certain amount of energy (calories) per day. If a low energy feed like hay is fed, cows can be full-fed. If corn is used to provide most of the energy, then intake has to be restricted so the animals don’t get fat. We have developed a limit-fed, corn-based nutrition program which has been tested with sheep and cattle. The procedures we used to meet the nutrient needs of gestating and lactating cows is outlined below. Some forage has to be fed to maintain a healthy rumen.
* Feed 4 lbs first cutting hay, supplement, and 12 lbs whole shelled corn (per cow basis). The rule of thumb here is to feed corn at 1% of cow body weight in mid-gestation. The protein and mineral supplement should be similar to that used for feedlot cattle fed a high-grain diet. Follow feeding instructions on the bag.
* Feed corn whole. Ohio State research shows that whole corn works better than ground corn when daily hay intake is limited to less than five pounds.
* Adjust corn intake to achieve desired weight and/or body condition score. You may need to increase corn in January and February due to increased energy requirements associated with cold temperatures and late gestation. We generally feed 12 lbs/cow/day until late December, and 14 to 16 lbs/day until spring turnout on pasture.
* When starting the program, take 7-10 days adjusting up the corn and decreasing hay to the 4 lb level. Make sure bunk space is adequate so all cows get their share and that cows are in a securely fenced area.
We have used this system on part of our cow herd at the Coshocton Branch for over 20 years with good success. Beef producers should not be afraid to feed shelled corn to cows. Corn makes a good energy supplement to improve (or maintain) cow body condition. It can also be used as the basis for the whole winter feeding program. In our work, limit-feeding corn throughout the winter resulted in the same cow performance as feeding hay (Table 1). If hay = $80/ton, corn = $3.00/bu, and supplement = $150/ton, it costs about $1.03/day to feed a cow with this system (Table 2). With these assumptions for feed costs, the breakeven value for hay would be $48/ton.
There are other feedstuffs available that may also be cheaper than hay on an energy basis. See this Fact Sheet in our OSU Beef Team Library web page: http://ohioline.osu.edu/as-fact/0001.html
This article by Steve Boyles and Cliff Little does a good job pricing alternative energy sources if supplementation is needed. Here are some additional thoughts in this regard. Dried distillers grains (DDGS) provide the same energy as corn and have 3 times the protein. A pound of DDGS will replace 2 pounds of hay. Procedures for feeding DDGS are the same as feeding corn, except no supplemental protein is needed. Soybean hulls are a great forage supplement, and are more economical than purchasing hay this year and most years. One pound of soyhulls is equal to about 1.5 pounds of hay.
Good quality hay is a great supplement to feed with average quality hay during peak cow energy needs, but purchasing good quality hay may be cost prohibitive. Five to eight lbs of corn/day is a cost effective energy supplement during late gestation and early lactation (corn will likely be a much cheaper source of calories than purchasing good quality hay). One effective option producers rarely consider is hay chopping. Chopping hay allows the cows to eat 25-30% more energy. Costs of chopping hay (equipment, labor, etc.) should be compared to costs of purchasing supplemental energy. For some producers, this may be a cost effective option. I came to realize the potential of hay chopping from an observation I made two years ago at the OARDC Beef Center in Wooster. Steers fed a chopped hay based diet gained 2.5 lbs/day while those fed round baled hay (same hay source) in a rack gained less than 1.5 lbs/day.
As outlined in the Boyles/Little article, there are several options for producers who need to increase energy intake because hay quality is insufficient. Be creative and sharpen your pencils!
5. Grazing Corn or Stalks. Grazing crop residues (such as corn stalks) is a simple and effective method for extending the grazing season. One acre of stalks will support a cow for up to 60 days. Our research indicates if we strip graze (moving fence twice per week) an acre will support two cows for 60 days. Only mineral and water is needed if this occurs in November and December.
We have also investigated strip grazing standing corn that has not been harvested. In this system, an acre will support two cows for about 110 days. We moved cows twice per week and gave them access to round baled hay for four hours before each move. Cows were hungry before each move because we wanted them to eat as much stalks as possible. Hay was provided so cows didn’t over consume corn immediately after fences were moved. Estimated feed costs for this system was $.60/cow/day.
Table 1. Effect of feeding stockpiled forage, limited corn, or hay to gestating cows (3 year average)
|No. of cows||31||24||17|
|Days on test||112||112||112|
|Initial wt, lb||1457||1457||1460|
|Final wt, lb||1557||1566||1563|
|Wt change, lb||100||109||103|
|Initial body condition score||6.5||6.5||6.5|
|Final body condition score||6.2||6.6||6.0|
|Body condition score
|Calf birth wt, lb||109||109||103|
|Cow wt, 7/12||1502||1526||1478|
|Cow body condition score,
|Calf wt, 7/12||400||415||408|
|Conception rate, %||91||86||96|
Table 2. Effects of three cow wintering systems on feed use (3 year average)
|No. of cows||31||24||17|
|Total harvested feed/cow|
|Total days of harvested feed||20.3||112||112|
|Harvested feed cost/cow/d
|Total harvested feed
|Pasture rental, $/cow/d||$0.43|
|Total cost, $/cow/d||$0.58||$1.03||$1.61|
a) Prices used: Corn = $3.00/bu, Hay = $80/ton, Supplement = $150/ton.