Cow-Calf Management Considerations During the Drought

Darrell Rankins, Jr.

In many parts of Alabama, pasture conditions have reached the point of zero forage availability and several producers have exhausted their hay supply. The following is a summary of some options that should be addressed for the cow herd.

First and foremost, early weaning should be given a high priority. This will dramatically reduce the nutrient needs of the cow and thus the quality and quantity of feed that she requires. For example, a typical cow requires 58% TDN (energy) and 10% protein in her daily diet while she nursing a 3 month old calf. If the calf were to be weaned we would reduce her requirements to 45% TDN and 6% protein. Once the calf has been weaned it can be sold immediately, fed until later this year on purchased feeds, assuming adequate facilities and labor exist or retained ownership may be an option.

Another priority decision would be to cull all open, old and non-productive cows. In essence, if culling the cow has ever crossed your mind, for any reason, now is the time to sell her. In addition, if you have a commercial cow herd, sell the bulls. Additional bulls can always be purchased later this year.

Now that the herd has been reduced to only pregnant cows and possibly a few bred replacement heifers. It becomes a simpler task as well as more economical to keep the herd fed. There are a variety of options for purchasing feeds. Because hay is so scarce, it becomes very difficult to continue to use hay in any appreciable quantity. One suggestion, would be to feed about 10 pounds of soybean hulls per head per day along with about 5 pounds of hay or some other source of roughage to insure adequate rumen function. The hay does need to be limited or they will most certainly consume more than 5 pounds per day. This becomes difficult if you have large round bales and a small number of cows. Currently, soybean hulls are about $70/ton when purchased in bulk (loose form, pellets are higher). A typical bulk load will be 22 to 24 tons and will occupy about 4,500 cubic feet of space. They could simply be dumped on the ground and covered with a sheet of black plastic with very little loss with the currently dry conditions. Make sure that you have adequate access and turnaround space for the 18-wheeler that will deliver the feed. If this is not feasible then you may be able to partner with one or more neighbors to make it feasible. The 5 pounds of daily roughage could be supplied by something other than hay if such by-products are available. A few such products that could be fed at 5 pounds per cow per day would include: peanut hulls, gin trash, cotton motes. Other energy dense feeds could also be fed instead of the soybean hulls. One such example would be corn; however, additional protein would need to be added in order to get the grain mix to about 12% which is what the soyhulls typically contain. An appropriate mixture would be to mix a 50-pound bag of soybean meal with 575 pounds of corn and then feed about 10 to 12 pounds of this mixture per day.

Another alternative feeding options would include the use of broiler litter which would be mixed at a rate of 80% litter and 20% grain and fed free-choice to the cows. They would consume between 25 and 30 pounds of this mix per day. For a complete summary of the use of broiler litter as a feedstuff please refer to ANR-557.

Many producers in the row crop areas of the state also have drought-stricken cornfields that could serve as an emergency feed source. Nitrate levels in the corn plants should be considered before turning the cows in. Cattle will generally graze the upper stalk, leaves and ears first. Fortunately, nitrates are usually highest in the lower stalks and lesser concentrations exist in the leaves and upper stalk. The best way to proceed is to actually take some representative samples of the corn and send them to the Forage Testing Laboratory at Auburn. Take several random samples from the field of both lower and upper stalks, then pool the samples such that you have one representative sample of the upper portion and one representative sample of the lower portion. Take these two samples to your local county extension office where you can fill out the appropriate forms for testing at the Forage Testing Lab, Funchess Hall, Auburn University, AL 36849. Indicate that you want a nitrate analysis.

Pay particular attention to the way in which the nitrate concentrations are reported. Some labs report it as nitrates (NO3) and some report it as nitrate nitrogen (NO3-N). Nitrate nitrogen is how the AU Forage Lab will report it. To convert nitrate to nitrate nitrogen multiply the nitrate level by .23.

The following guidelines can be used once the level of nitrate nitrogen has been determined. 0 to 575 ppm NO3-N: Generally considered safe.

575 to 1150 ppm NO3-N: Use caution. Allow cattle to graze this forage for less than 2 hours after having access to hay for 3 to 4 hours. Do not feed with liquid feed or other non-protein nitrogen sources. Be careful with pregnant and young cattle.

1150 to 3450 ppm NO3-N: Dangerous level. Limit to one-fourth of the total intake. Adequate levels of Vitamin A should be provided.

greater than 3450 ppm NO3-N: Potentially fatal. Can be used in very limited amounts but will need to be mixed with other feeds or hand-fed.

In summary, the best policy is to have the corn tested for nitrate prior to use by cattle. Other potential problems will be from hay that will be produced when (if) it rains. That hay will be potentially high in nitrate levels so it would be a good idea to have this year's hay tested, if any is ever produced.

Animals experiencing nitrate toxicosis may show signs of labored breathing, muscle tremors and a staggering gait, after which the cow falls down, gasps for breath and dies quickly. The cause of death is lack of oxygen and the membranes of the eyes and mouth are usually bluish while the blood will be reddish brown and turns brighter red once exposed to the air. If prompt action is taken some animals can be saved so it is advisable to call a veterinarian as soon as possible.

Several other management factors need to be considered as well. The cattle must have an adequate supply of drinking water. The most recent beef cattle NRC publication suggests that the requirement would be somewhere between 15 and 20 gallons per day at 80o F. Another factor to consider is that the animals will likely eat plants that they would not normally consume. Some of which may be toxic. Check pastures for toxic plants especially in the low-lying and shaded areas. For a complete listing and discussion of these poisonous plants check out ANR-975.