Beef Cow Rations and Winter Feeding Guidelines

July 2008 

Introduction

Feeding beef cattle during Saskatchewan winters can be a challenging experience. Frame size, body condition, feed quality, types of feed and fluctuations in air temperatures all impact on feed consumption and rates of gain.

Over-feeding is costly and wastes feed while under­feeding affects body condition and may cause poor performance in the breeding herd.

The Cowbytes® Ration Balancing software, available from Alberta Agriculture and Rural Development, was used to develop the rations in this guide. It utilizes prediction equations based on the National Research Council "Nutrient Requirements of Beef Cattle - 2000 Update".  Long term average feed nutrient values were used.

More accurate rations can be developed by having your feeds analyzed at a feed testing laboratory. The results of the feed analyses can then be incorporated into the Cowbytes® software.  The services of a beef nutritionist can assist in developing rations.

The rations contained in this guide were designed to provide an acceptable level of nutrients required by 1,200 lb. and 1,400 lb. cows. The following information and rations are intended to be used as general guidelines.  Responsibility for interpretation of the rations rests with the user.

Body Condition of the Cows

The body condition of cows at the start of the winter feeding period has a major affect on the amount and quality of feed required.  Cows have greater difficulty gaining weight in cold winter conditions than during fall when temperatures are warmer.  Thin cows must gain weight throughout the winter feeding period.  They require a good quality forage or average quality forage with supplemental grain or pellets.

Cows in good condition in the fall do not need to gain actual body weight. They need enough feed to gain weight equal to the weight of the calf and calf bed. This usually amounts to 150 to 180 lb. of gain in an average sized cow.  This mass is lost the day the calf is born.  Average quality hay fed with small amounts of grain or pellets should meet the winter feed requirements of these cattle.  If your cows are in good condition (a body score of three to 3.5), select rations that will give zero lb. of average daily gain. The rations in this guide have been designed to account for the weight of the fetus and calf bed.

Low Quality Feeds - Cold Weather Feeding

Sudden drops in temperature during the winter months will cause cows to consume more feed.  If cows are fed poor quality feeds such as straw, they will attempt to consume more than they can digest and may become impacted.  Processing the poor quality feed through a hammer mill or tub grinder will only increase feed intake which increases the potential for impaction when sudden drops in temperatures occur.

During periods of cold temperatures, increase the energy component of the ration by feeding additional grain or pellets at a rate of one lb. per head per day for every -5º C that the temperature is below -20º C at mid­day.  For example, if the afternoon air temperature was -35º C, feed an additional three lb. of grain or pellets per cow.

Divide the Herd into Different Feed Groups

If the ration is based on straw or low quality hay, or if feed intake is limited, separate the herd into different feeding groups to match the nutritional needs of each group.  Feed analyses provide important information on the nutrient levels of the feeds and should be used to accurately formulate rations.

Group I - Mature Cows in Good Condition  Average quality hay supplemented with grain or pellets, minerals, fortified salt and vitamins, will generally meet the nutritional needs of this group.

Group II - Bred Replacement Heifers and Second Calf Heifers  These young growing animals do not compete effectively for feed with the mature cows.  The heifers require good quality hay and extra grain to meet their needs for growth and development. These animals are gaining body weight in addition to the developing fetus.

Group III - Thin and Old Cows  These cows will need extra energy to get them through the winter.  Some older cows may have hardware disease or may not have sound teeth.

If the cow herd cannot be divided into three groups, heifers and the thin or old cows could be fed together.  A second option is to cull the thin or old cows rather than trying to feed them over the winter.

Salt and Minerals

Nearly all winter feeding programs for cows require the use of additional salt and minerals.  Trace Mineralized Fortified Salt (TM Fortified Salt) has gained widespread acceptance.  It contains similar levels of iodine and cobalt as found in blue salt.  In addition, it contains a number of important and necessary trace minerals (copper, zinc, manganese and sometimes selenium). These trace minerals are commonly deficient in Saskatchewan grown forages and grains used for beef production.

Grass or legume-hay rations generally require the addition of a 1:1 mineral (equal parts of calcium and phosphorus). Rations based on greenfeed, cereal silage, straw-grain mixtures or rations containing high amounts of grain or pellets, often require additional levels of calcium.  Provide a 2:1 mineral (two parts calcium to one part phosphorus) or a 3:1 mineral.  Most cows require 1 to 2 oz. of mineral per head per day.  Some producers provide a 1:1 mineral and add additional limestone which contains about 36 per cent calcium. Feed grade limestone is available at most feed supply outlets and is inexpensive.

TM Fortified Salt can be mixed with the minerals. This will encourage the cows to consume the mineral on a free-choice basis.  A common mixture is one part loose salt to two parts mineral.  All other sources of salt must be removed from the cows to ensure that they will consume enough of the salt-mineral mixture.  Commercially available minerals can be purchased that have salt premixed with the mineral.

The cow's daily requirement for mineral increases after calving and throughout the milking period.  A 1:1 or 2:1 mineral is usually required.  Heavy milking cows may require additional calcium and phosphorus. Feed grade limestone or 3:1 mineral can be used. The mineral should be mixed with grain or concentrate to ensure adequate intake. Another option is to feed fortified pellets.  These pelleted products are fortified with minerals, trace minerals, vitamins and salt.  They are often competitively priced against barley.

Remember, "Cows eat what they like, not what they need". Cows will eat until full, given voluntary free-choice access to feed.  Cows do not balance their nutrients or nutritional needs, only their intakes.  In fact, cows can only balance four things:

• the air they breathe
• the water they drink
• the amount of feed they consume each day (given voluntary free-choice access to feed)
• salt (and only when sodium levels are not excessive in the water or feed)

On a free-choice basis, feed supplements and minerals are consumed in a "hit and miss" fashion. Some cows will eat the required amount, some cows will consume excessive amounts and others will ignore the supplement or mineral.  It is better to mix the feed supplement or mineral into a small amount of grain or pellets (three to four lb.  per head per day).  Ensure that each cow receives her share. The other option is to feed fortified pellets containing a balance of minerals, vitamins and supplements.

Having the feeds analyzed will give a much more accurate account of the amount and type of minerals and supplements that your cows will require.

Trace Mineralized Fortified Salt was used to formulate these rations.  If selenium is being supplemented, use a single source of selenium.  If selenium is contained in more than one source of supplement (example : fortified salt and mineral), check with a beef nutritionist to ensure that a safe level of selenium is being fed.  Excessive amounts of selenium can be toxic.

Vitamins

Vitamins are measured in International Units (IU's). Grains contain little or no vitamins.  Forages and silage contain highly variable levels of vitamins.

Vitamin levels decrease as storage times increase. It is best to assume that cut forages supply no vitamin A.  Prior to calving, beef cows require 40,000 to 50,000 IU's of vitamin A per head per day.  After calving and prior to grazing green grass, each cow needs 70,000 to 90,000 IU's of vitamin A daily.  Vitamin A is stored in the liver and is used when needed. It can be fed daily, weekly, monthly or it can be injected once every two to three months. Feed the required amount daily or once per week. The vitamin pre-mix can be blended with grain or concentrate.  Many mineral and beef supplements also contain varying levels of vitamins.

A common source of vitamin A is a pre-mix of vitamin A-D-E containing 10,000,000 IU's of vitamin A per kg. One-quarter (0.25) oz. of this vitamin supplies 71,000 IU's (1.0 oz. of this vitamin pre-mix supplies 284,090 IU's).  Exercise caution if using "triple strength" vitamin.  These products contain 25 million to 30 million IU's of vitamin A per kg. They often contain high levels of selenium (1,000 to 1,200 mg per kg). Over feeding this material can lead to selenium toxicity problems in cattle.  Ensure that proper levels are being provided.

The vitamin A-D-E pre-mix used in these rations contains 10,000,000 IU's of vitamin A per kg. Vitamin pre-mixes from different manufacturers contain varied levels of vitamin A-D-E.  Follow label directions carefully.  Measure and be sure.

Water

• during winter, a mature cow will consume 10 to 15 gallons of water per day
• have the water analyzed to determine levels of dissolved minerals
• minerals contained in water are additive to minerals contained in feeds
• sulphates can impair copper absorption causing copper deficiency
• nitrates can cause production problems
• high levels of Total Dissolved Solids can reduce weight gains and causes scouring
• watch for other contaminants

Analyze the Feeds and Monitor the Cattle

The rations provided in this package of information were formulated using long-term average feed values.  It is advisable to feed test each of the feed components prior to the start of your winter feeding program.  Analyses of the hay and silage are most important as the nutrient levels can vary dramatically.  The nutrient levels in straws and grains tend to have less variability but a feed analysis is recommended for these feeds as well.

During the winter feeding period, the condition of the cattle must be observed.  Adjust the rations to accommodate the body condition and appetite of the cattle, changes in the weather and differences in feed sources.  Watch for moldy feeds which can cause serious problems in pregnant and lactating cows.

Cold Weather Feeding

The sample rations in this package are based on feeding cattle during normal winter temperatures which range from -10 degrees to -20º C. Feed an additional one lb. of grain or pellets per head per day for every five degrees that the temperature is below -20º C at mid-day.

60 Days Prior to Calving

Decrease the amount of roughage fed by approximately 15 per cent and increase the amount of grain or pellets fed by 15 per cent. The capacity of the rumen decreases as the fetus develops, especially during the last half of the third trimester.  As the unborn calf develops, it occupies more and more space within the body cavity.

After Calving - Lactation

Milk production places a significant increase on the cow's requirements for energy, protein and minerals.  When feeding high grain rations or high volumes of pellets, feed one-half of the grain or pellets in the morning and the other half in the afternoon. A 1,200 lb. cow can safely eat about seven to eight lb. of grain or pellets at one feeding.  Ensure there is adequate feed bunk space to minimize crowding. The larger or more aggressive cows will often eat more than their share of concentrate. Smaller or less aggressive cows may not have access to their share.

Reduce or eliminate forced feeding of straw after calving. Most straw rations do not provide adequate levels of energy during the lactation period. If cattle are fed a straw-grain ration, provide a good quality protein supplement such as canola meal, alfalfa pellets or a commercial beef protein supplement after calving.  Adding any type of hay, even slough hay, to a straw ration will improve the nutrient supply to the cow.

Make Allowance for Feed Wastage

No allowance was made for feed wastage in these rations.  Wastage can range from five to 25 per cent or more depending on the type of feeding system in use.

Limit Feeding or Restricting Feed Intakes

• Feed about one per cent of the cow's body weight as dry matter forage per cow per day. The energy and protein must be balanced by feeding an appropriate amount of grain or fortified pellets.
• To avoid digestive problems, the forage should be fed whole or if processed, it should not be shredded shorter than three inch lengths.
• The forage should be fed in the morning prior to feeding the grain or pellet concentrate.
• Do not feed more than six or seven pounds of concentrate at one feeding. Ideally, provide some straw or poor quality roughage such as slough hay prior to the afternoon feeding of concentrate to reduce digestive upset.
• It is important to supply a balanced ration that meets all mineral, vitamin and salt requirements.
• Cows on this type of a feeding program will be hungry as their dry matter intake is not being met.
• Ensure that each animal is receiving its share of forage and concentrate. Cows should be in good body condition prior to the onset of cold weather. Adjustments to the feeding program should reflect changes in outside air temperatures.
• Provide adequate bedding and shelter from the wind to reduce effects of cold stress.

Molds and Molded Feeds

• The nutritional value of molded feed is reduced.
• Molded feeds can be very dusty due to the presence of mold organisms and spores. When the dust is inhaled, a type of fungal pneumonia may develop. This type of pneumonia is difficult to treat.
• Some spores may pass through lesions in the rumen wall and are carried by the bloodstream. The spores may settle in the pregnant uterus causing uterine infections and mycotic abortions.
• Some spores produce toxins which can be extremely potent. These toxins can cause abortions or weak, deformed calves. Other symptoms include internal bleeding, vaginal and rectal prolapse, gangrene-like symptoms and paralysis.
• Estrogenic compounds produced by some molds may affect lactation and cycling.
• Some toxins are extremely poisonous to cattle. Ideally, do not provide molded feeds to pregnant or lactating cows. Diluting molded feeds with good quality feeds may help reduce the potential for problems.
• Supply adequate levels of vitamin A if molded feed must be used.
• There are several tests available to screen for the presence of mold organisms and toxins.

Feeding Considerations and Precautions

Table of values of feeds and supplements used to develop the Beef Cow Rations (PDF )

Alfalfa Hay

• Potential for frothy bloat.
• Tends to have high protein and energy levels.
• Use a 1:1 mineral.

Alfalfa - Grass Hay

• Use a 1:1 mineral.
• Usually contains good levels of protein and energy.

Example rations utilizing alfalfa grass hay (pdf file 19KB) 

Canola Hay

• Canola hay makes a surprisingly palatable and nutritious hay.
• Cut in the late bloom to mid-podded stage, crude protein averages about 15 per cent, total digestible nutrients (TDN or energy) 60.4 per cent, acid detergent fibre (ADF) 35.8 per cent, and calcium 1.16 per cent (values on a dry matter basis). This hay is similar to a good quality alfalfa grass hay.
• Cut at a later stage of development, canola that is fully podded and stemmy with little or no leafy material left on the plant, crude protein averages about 10 per cent, TDN 49.8 per cent, ADF 45.9 per cent, and calcium 1.1 per cent. This feed is less palatable and, nutritionally, is more like slough hay.
• Canola can accumulate high levels of nitrates. A test for nitrates is recommended.
• Producers using canola as hay or silage should be providing trace mineralized salt containing copper levels of 2,500 mg per kg or higher, and selenium at 90 to 120 mg per kg. Minerals should contain sufficient levels of copper 2,500 mg per kg or higher, and selenium at 25 to 60 mg per kg. High levels of dietary sulphur can inhibit copper absorption and causes copper deficiency.
• The National Research Council "Nutrient Requirements for Beef Cattle" recommends that the total dietary intake of sulphur should not exceed 0.4 per cent of dry matter intake. Sulphur levels of canola can range from 0.5 per cent to 1.3 per cent or higher. High levels of total dietary sulphur initially reduce feed intakes and lower rates of gain. As sulphur levels increase in the rumen, the production of thiamine (vitamin B1) is impaired, and scouring may become evident in affected animals. Thiamine deficiency may develop, especially in younger animals. High levels of dietary sulphur can also result in polioencephalomalacia (PEM). If left unchecked, death can occur.
• It is important to have canola forage analyzed, ensuring that sulphur is included in the analysis. Canola hay or silage can be an excellent feed, but as a precaution, producers should limit its total intake to 50 to 60 per cent of the total ration on a dry matter basis.
• Use a 1:1 mineral.

• Canola cut for silage during the early to mid podded stage of development, averages about 16 per cent crude protein, 56.3 per cent TDN, 36.8 per cent, and 1.2 per cent calcium (dry matter basis).
• Swathed canola may have to cure for several days to dry down to 60 to 65 per cent moisture.
• It makes excellent quality silage (baled or chopped and packed in a pit).
• Same feeding precautions as canola hay.
• Use a 1:1 mineral.

Example rations utilizing canola silage (pdf file 19KB)  

Cereal Greenfeed

• Cereal greenfeed can accumulate high levels of nitrates. A test for nitrates is recommended.
• Greenfeed can also accumulate high levels of potassium. High dietary levels of potassium have been associated with milk fever (hypocalcaemia). Greenfeed contains low levels of calcium. It is important to supplement cereal greenfeed rations with extra calcium to avoid milk fever problems in cows.
• There may be rodent problems in hay stacks of greenfeed when stored over the summer.
• Greenfeed can be stemmy. Crimping during swathing and grinding or bale processing may help to reduce feed wastage.
• Use a 2:1 or 3:1 mineral and add additional limestone.

Example rations utilizing cereal greenfeed (pdf file 19KB) 

Cereal Silage

• Same precautions as cereal greenfeed.
• Use a 2:1 or 3:1 mineral and add additional limestone if required.

Example rations utilizing cereal silage (pdf file 19KB) 

Cereal Straw

• Straw has low levels of protein and energy. It is less digestible than hay or greenfeed.
• A cow might consume 25 to 30 lb. of straw in a 24 hour period but the microbes in the rumen can only digest about 1.25 per cent of the cow's body weight as dry matter straw.
• Example: 1,200 lb. cow x 1.25 per cent = 15 lb. of dry matter straw per day, adjust for moisture content of straw. (12 per cent moisture content or 88 per cent dry matter)
• o 15 lb. divided by 0.88 = 17 lb. of straw (as fed) per day.
• Impaction may occur if properly balanced rations are not provided.
• Ensure adequate levels of vitamin A are fed.
• Provide good source of energy (grain or pellets).
• Ensure that adequate protein is supplemented.
• Generally, straw rations are not good rations for Lactating cows
• Use a 1:1 mineral

 Example rations utilizing cereal straw (pdf file 19KB)

Clover Silage

• As with hay, moldy sweet clover silage can result in the formation of dicoumarol which causes bleeding diseases in cattle. Do not feed molded sweet clover silage to pregnant cows.
• Other types of clovers do not form dicoumarol.
• Use a 1:1 mineral.

Example rations utilizing clover silage (pdf file 19KB)

Grass Hay

• Use a 1:1 mineral.
• Some grass hays can be dusty.

Example rations utilizing grass hay (pdf file 19KB)

Lentil, Pea or Chickpea Hay

• Use a 1:1 mineral.
• These forages are legumes containing good levels of calcium.
• These crops can be infected with various fungus diseases which can make the feeds dusty. Diseased crops do not contain toxins and are not harmful to the cows (other than being dusty which might cause problems in the lungs).

Example rations utilizing Lentil, Pea or Chickpea Hay (pdf file 19KB) 

Lentil, Pea or Chickpea Straw

• Use a 1:1 mineral.
• Dry matter intakes are generally higher than cereal straw.
• Maximum daily intakes are approximately 1.6 per cent of the cow's body weight on a dry matter basis.
• Example: 1,200 lb. cow x 1.6 per cent = 19.2 lb. dry matter straw per day, adjust for moisture content of straw. (12 per cent moisture content or 88 per cent dry matter)
• o 19.2 lb. divided by 0.88 = 22 lb. of straw (as fed) per day
• This straw can be dirty and dusty. It is often stemmy with less leaf material than the same material cut as hay. Palatability may be less than desired. Grinding or processing this feed often increases consumption levels with less feed wastage.

Example rations utilizing Lentil, Pea or Chickpea Straw (pdf file 19KB)  

Slough Hay

• Often lower in protein and energy than grass hay.
• Usually provides adequate levels of nutrients to winter a pregnant cow.
• Cold weather and lactation rations always require additional grain or pellets.
• Watch for poisonous plants. Avoid grinding or processing bales if poisonous plants are a concern. Roll out those bales and allow cows to selectively eat the hay.
• Use a 1:1 mineral.

Example rations utilizing Slough Hay (pdf file 19KB)