| ||Feeding the breeding herd and, for that matter, backgrounders, is a fine balance between managing for low cost, appropriate nutrition and minimal waste. Over the past number of years at Alberta Agriculture's "Ag-Info Center" I've fielded many calls on beef nutrition and feeding systems. As I thought about these calls, a number of common questions and themes appeared. I thought these would make a handy reference list for Alberta beef producers so I've summarized them into a short list with supporting discussion points.
Quality and quantity of livestock feeds for the winter are equally important. However, all too often producers measure their winter-feeding program by the pounds of feed delivered to the animal. Types of feed ingredients, method of harvest, dry matter intake, and weather conditions all affect how well cattle will perform over the winter. Here are a few tips on cattle nutrition and feeding that can help you build the best ration and feeding system for your herd.
1. Balance Rations and Test Water
2. Estimate Feed Intake
- Test feed ingredients, at a minimum, for moisture, protein, energy, Ca and P. Silage with a pH over 5.2 doesn't keep very long so needs to be tested too. Deficient protein and energy result in low birth weights or weak calves and poor milking cows. Excess protein and energy are expensive and wasted.
- Feed for the requirements of the cattle, not how much they will eat.
- Periodically (every 3-5 years) have a chemical analysis of water sources. Mineral imbalances in water can interact with feed nutrients.
3. Estimate and Adjust for Feed Waste
- Feed intake will be dependent on feed quality and animal size and performance.
- Heavily pregnant animals cannot eat as much as dry or early pregnancy cattle. Older cattle eat more per unit body weight than younger cattle. DMI, as a % of body weight, can vary from 1.5% on straws to 2.75% on quality alfalfa hay.
- Newly weaned calves will have decreased intakes, so they need to be fed accordingly.
- Cold stress on cattle may increase dry matter intake because it increases rate of passage.
4. Use Ionophores in Rations
- Feed type and delivery method affects what and how much is wasted. Although tub grinders and hay shredders may reduce length of feed, fine material may be lost. The finer material may be the higher quality, higher protein portion of the feed.
- Hay and greenfeed typically have a feeding waste of 15-30%. Grain and pellets have a waste factor of about 5%.
5. Limit Feed Cattle
- Rumensin and Bovatec are approved for beef cattle. Rumensin provides increased feed efficiency (8-12%), increased rate of gain (5-15%), prevents coccidiosis and decreases acidosis and grain bloat.
- Look for a $2 to $3 return for every $1 spent on an ionophore. Bovatec is more expensive but acts less like an appetite suppressant compared to Rumensin. Cattle must have an adaptation period of about 5 days, after which they can be fed higher recommended rates.
6. Put Condition on Cattle Before High Demands of Pregnancy
- When mature cows are not under cold stress, limit feeding can extend feed supplies.
- Rumen capacity will adjust to the amount of roughage offered in a ration.
- Focus on meeting the nutrient requirements of the animals. Intake levels can be adjusted when limit feeding cattle.
7. If Cold Stressed, Feed Cattle Later in the Day
- The high nutritional demands of late pregnancy make it difficult to put weight on cows which are thin. Feed intake of lactating cows is 30-50% higher than pregnant cows.
- Feed cows to gain weight when it is cheapest (fall weather) and when they are not heavy in pregnancy.
8. Be Aware of Mineral Imbalances When Feeding Cereal Crops
- Some research suggests late afternoon feeding makes more heat available to them during and after digestion when they need it most.
- Heat increment of feeding will then be highest closer to the coldest part of the day.
9. Don't Change Ration Ingredients Too Abruptly
- Winter tetany can be a problem if feeding only annual cereal crops (greenfeed, silages or straw). It mimics milk fever in symptoms. Supplemental minerals are cheaper in the long run than treating downer cows or lameness due to mineral imbalances.
- Supplement extra Calcium and or Magnesium to offset effects of high Potassium in annual cereal roughages.
10. Limit Oilseeds or Fat Sources
- High concentrate rations should be stepped up by no more than ½ pound per head per day.
- Grain added to high roughage rations should be introduced gradually. Start with no more than 1/3 of the ration as grain. Ex. 600 lb feeder calves on 5.5 lbs grain.
- Grain needs to be fed daily. Alternate day feeding of grains at high levels can result in acidosis or bloat.
11. Prepare for Mineral Imbalances When Feeding Canola
- Maximum fat in a ration for beef animals is 5 to 7% of the ration dry matter (tallow=177% TDN). Oil or fat is an excellent energy source, but price and storage of product has to be evaluated.
- Oilseeds like canola (25% to 35% oil) or sunflowers, if fed at too high of levels will interfere with fibre digestion, but also lowers methane production. (Ex. 1400 lb cow eating no more than 3-4 lbs whole canola seeds.)
12. Test for Nitrates
- Canola roughage generally has high sulfur levels (up to 2.5%). Cattle require 0.4% sulfur.
- Excess sulfur can result in PEM (polioencephalomalacia).
- High S interferes with Copper and Selenium so dilute a canola ration with low S feeds.
13. Feed Heated Bales Before They Mold
- If feeds are suspicious (frosted greenfeed, heavily fertilized or manured annual cereal crops or heated greenfeed bales) test for nitrates.
- Greenfeed bales which are low in nitrates can be dangerously high in nitrites if they heat. Nitrate conversion to nitrite can be deadly.
14. Don't Process All Grains for Cattle
- If not high in nitrates, feed heated bales early.
- Heated bales have less available protein and energy (CP requirements increase as the fetus grows in the uterus). Match the quality of the feed to the cattle requirements.
- With time and changes in weather (chinooks), molds can develop and increase. Mold can be just as harmful if inhaled, as it is if digested.
15. Don't Use Snow as a Water Source for 1st and 2nd Calf Heifers
- Don't process oats and corn for mature, healthy cows. Increase in digestibility is at most, 10-15%.
- Do process barley and wheat for cows if economics make sense. Increase in digestibility is 15-25%.
- Don't process any cereal grains for calves under 600 lbs. (if intake is acceptable). Younger cattle chew feed more completely.
16. Limit Amounts of Urea in Rations
- If feeding poor quality roughages to breeding females under 3 years of age, provide fresh water. First and second calf heifers are still growing plus maintaining a pregnancy, so protein and energy requirements are higher than mature cattle.
- Snow is acceptable as a water source for mature cows and young cattle in good condition. Snow needs to be clean and not ice packed to be best utilized.
17. Convenience Feeds May Not Be Convenient for Your Wallet
- Urea or other NPN sources should be limited to 0.5 to 1% of ration DM. Too much results in increased blood ammonia levels. Cattle need to be adapted to urea over a period of 10-14 days.
- Low energy rations (high forage, low grain) result in low urea utilization since ammonia will be lost in the urine. (Read labels on supplements since 32-12 protein supplements are better suited to low grain rations compared to 32-20 which is designed for high grain feedlot rations).
- Do not feed urea to calves under 400 lbs as their rumens cannot handle the urea.
18. Not All Cattle Have to be Bedded
- Protein is an expensive nutrient to supplement. If additional protein is not needed in the ration, certain products with protein in addition to minerals, and vitamins will be more expensive than supplementing only the needed nutrients.
19. Choose Salt Sources Carefully
- Winter bedding is not required if cattle have access to areas protected from the wind and are not wet or muddy/slushy.
- Bedding is required if cattle are in a dry-lot and space is an issue and/or if no clean snow is available.
20. If Using Cowbytes …
- Have only one source of salt fed free choice.
- Mineral fed free choice and salt blocks free choice are a waste if put out together. Cattle tend to have either a salt craving or consume a product because it is sweet. If salt and mineral sources are separate, cattle may not eat required amounts of both, rather they will lick the salt and not the mineral.
- Don't underestimate cow weight or overestimate bale weights. There is up to 100 lbs difference in a condition score.
- Default number for calf birth weight can be low for most herds (77 lbs). Typically, you should target for a calf's birth weight to be 7% of the cow's body weight (1350 lb cows having 92 lb calves).
- Lactation month affects energy requirements. Milk production peaks at 12 weeks post calving.
Feeding cattle is a fine balance. You want to feed cattle to perform, but to minimize the cost of getting this performance. Although this issue goes deeper than just what's put in front of your stock, feeding effectively within the system you use is a good first step. This checklist should serve as a helpful guideline for producers to get the most of the feeds they have on hand.
Dr. Susan Markus
Beef Specialist - Ag-Info Center