Managing Heat Stress

As temperatures rise, producers may need to pay closer attention to their synchronization programs.

Working cattle in hot weather can be detrimental to heat synchronization and artificial insemination (AI) programs, says Julie Walker, beef specialist for South Dakota State University (SDSU). When cattle need to be moved or worked, it pays to watch weather forecasts and try to choose a day that won’t be during a heat wave. Sometimes, however, producers need to get cattle in for a heat-synchronization program, and timing is crucial, regardless of the weather. 

Walker says more producers are shifting to April-May calving to match forage with nutritional needs of the lactating cow and to reduce labor at calving to avoid having to worry about cold weather in February-March. Now, she says, they have to deal with the heat instead. 

“They are breeding cows in July and August — which are often the hottest months, Walker explains. “This means that if they are putting CIDRs® in and synchronizing, and have to pull the CIDRs at a given time, they are under the clock and may have to get those cows in when it’s very hot. If they are going to do a fixed-timed AI in the morning, they are probably going to be pulling CIDRs at 7 p.m. the evening before.”

This can translate to more time and labor, particularly if cattle are away from AI facilities, she says. “If the cattle are not very close to the corrals, and we have to pull CIDRs at 7, this might mean we have to go get the cattle at 4 or 5 p.m., and that’s still during the hottest part of the day. We won’t be able to give them any time to rest and cool down and rehydrate because we have to sort off the calves before we put the cow through the chute. This often equates to 3 hours of working those cattle in the heat of the day,” she says.

Think about the heat and plan ahead, Walker urges. Consider moving cattle closer to the corrals in the morning while it’s still cool. That way, cattle are refreshed and watered before being worked, and maybe moving them will take less time. When moving and working cattle that time of year, make sure there is ample clean fresh water for them, so they won’t have any hesitation about drinking and getting rehydrated, she says.

If you’re using a fountain-type tank, make sure there’s enough water pressure to keep it full, Walker says, and make sure calves can reach the water. 

“We always need to think about heat stress and take care to minimize it while moving or working cattle, because heat stress can impact reproduction,” she says. “A lot of the risk is during early pregnancy for cows, and heat also has a negative impact on bull fertility.” 

Producers should also take into consideration that if you are doing heat detection during hot weather, cows won’t be very active during the heat of the day; they will be lying around in the shade to stay cool. You’ll have your best luck checking cows early in the morning or late in the evening, Walker notes, and they may be most active at night.

“When breeding cows that late in the summer when it’s hot, it really helps with the heat detection to use patches on them, to know which ones have been ridden,” she says. “We may not be out there during the coolest part of the day or night to see the riding activity, so we can use that tool to help us identify the cows that need to be inseminated.”

Editor’s Note: Heather Smith Thomas is a cattlewoman and freelance writer from Salmon, Idaho.

5 questions to ask before grazing corn stalk residue

5 questions to ask before grazing corn stalk residue

Here are five questions to ask before turning the cows on stalks, including: 

1. What’s left in the field? 

After the corn crop has been harvested, it’s good to know what’s left for grazing. It’s estimated that approximately 50% of the weight of the total corn plant remains in the stalk, leaf, cob and husk components. According to a report from Iowa State University’s Extension Beef Center, “For each bushel of shelled corn produced per acre, 50 pounds of residue is also produced. For example, an acre yielding 120 bushels of shelled corn per acre will produce approximately 6,000 pounds of corn residue.”

2. How long will it last?

With good weather conditions, it’s reasonable to assume that 1 acre of corn residue will provide 60 days of grazing for a 1,000-pound animal, according to the report. In the article from Iowa State University, “Mature cows in the middle trimester of gestation that are in desirable body condition typically maintain their body weight and may gain up to 1 pound per head daily. As the grain component is consumed and availability of husks and leaves declines, protein supplementation may be needed to maintain body condition.”

3. When should I supplement?

Fall calving cows may need protein and energy supplementation, and because corn stalk residue is typically low in a number of minerals as well as vitamin A, a balanced mineral and vitamin mix should be offered free choice. According to the report, “To determine if supplementation is necessary, observe the manure. If little or no corn is visible, protein supplementation should be considered. Sources include alfalfa, corn gluten feed, distillers’ grains.

4. How can I extend the grazing time?

Cattlemen should consider strip grazing to make the corn stalks last longer and offer a more uniform quality of diet. Limiting the amount of stalks the herd can graze at once will force them to be more efficient and consume both the high and low-quality components of the residue. Strip grazing can also limit the damage on the field due to mud or icy conditions.

5. Should I be worried about nitrate toxicity?

According to the report, “Another issue can be nitrate toxicity—especially during drought conditions. The highest level of nitrate concentration in the corn plant is in the lowest part (18-24 inches) of the stalk. This area is typically the last to be grazed by cattle. Therefore, the potential for nitrate issues is unlikely. Soil compaction can also be a concern. Recent research from the Iowa State University Leopold Center for Sustainable Agriculture suggests that compaction is not an issue once the ground is frozen. Prior to freezing, there is potential for slight reduction in yield for no-till soybeans, although there was no difference in soybean yield in conventionally tillage systems.”


by   in BEEF Daily

Beat the Heat with These Summer Management Tips

The days are getting longer, the nights are shorter, and the heat of the summer is sneaking up on us quickly. As we move into warmer days, here are a few quick tips to keep in mind:

Water, Water, Water

When was the last time you thought about HOW MUCH water your cattle need on a daily basis? You might be surprised about how much this need increases during the summer months.

Water is one of the five basic classes of nutrients required for all classes of beef cattle, and makes up about 98% of all molecules in the body. It is critical for a range of body functions including growth, reproduction, lactation, digestion, temperature regulation, and waste removal. Daily animal water requirements are dependent on the stage of production, physical activity, type of diet, feed intake and the environment. There is nothing like a cold drink of water on a hot day, and water intake is often greatest during the summer months for beef cattle. Water requirements roughly double as the temperature increases from 50 to 95°F. In general, as the size of the animal increases, water requirements also increase. The following table illustrates the daily water intake needs in gallons at various stages of production:

Mature, lactating cows can consume more than 20 gallons of water per day during hot weather. Check water sources often to make sure an adequate supply of clean water is available to animals. Providing easy access to a quality water source is important in maintaining adequate water intake and animal health.

Prevent Pesky Pests

Fly populations begin to increase during the summer months, and control and prevention programs are necessary. One of the most common fly problems in the Southeast is associated with the horn fly. It is estimated that the horn fly causes close to $800 million in economic losses nationwide to cattlemen every year. Horn flies can cause significant blood loss and change animal behavior. Cattle begin to alter grazing patterns, gather in groups, and may have significant energy losses associated with battling horn flies. Reduced energy can often mean decreased milk production and calf weaning weights.
There are several prevention options available for fly control in beef cattle. Whether it is ear tags, sprays, dust bags, etc., the most effective fly control programs rotate between products containing different chemical classes to prevent resistance. Resistance occurs when a product is highly effective at controlling flies for a given period, but then quickly becomes ineffective. Using products with the same active ingredient for an extended period of time decreases fly control effectiveness. In order to decrease resistance, rotating between pyrethroid and organophosphate-containing products is recommended. If insecticide-containing ear tags are used as a control method, a 4-year tag rotation system is suggested. For example, a tag containing organophosphates is used for the first two years, followed by a pyrethroid tag in the third year, and then an organophosphate tag in the fourth year. The use of a pyrethroid tag for more than two years in such a rotation is not recommended. Remove tags at the end of the season to prevent flies from being exposed to low levels of insecticide that can lead to resistance. In the case of horn flies, do not begin to treat cattle until flies exceed the threshold of 200 flies per animal. At this point, it becomes economically advantageous to treat animals and the chance for insecticide resistance is decreased. As always, it is important to follow the label directions for animal health products for them to be used safely and effectively. For more information on fly control, refer to publication ANR-2083 Fly Control for Alabama Cattle Operations.

Plan Your Work, and Work Your Plan

Planning your stored feed needs for this winter can never start too early. We are in the midst of the hay-making season, and many of you may have already put up an ample supply for the winter if. Certainly Mother Nature can be our friend or foe during this time of year when it comes to the hay business, but forage maturity at harvest is extremely important for producing high-quality hay. Conduct a forage analysis to know if supplementation will be needed this winter to meet animal nutrient requirements. Supplemental feed prices are generally quite high in the winter months, and it is advantageous to plan now for expected feed needs when a lower price point may be observed. The lowest prices of commonly used sources such as corn gluten feed and soyhulls are usually seen from early May to early July. After this, prices begin to increase through the winter months. The best way to save on feed costs is to watch prices and have an adequate storage facility to capitalize on low prices and store feed until your time of need.

In summary, the most effective managers balance their day-to-day tasks while planning for the future. By using these practices into our management systems, we can beat the heat and push through the dog days of summer

on the SE Cattle Advisor website.