Melissa Bravo, agronomic and livestock management consultant
Previously published in Hay & Forage Grower: April 21, 2020)
Here we go again. Another mild winter of heave and thaw with little snow cover to protect the shallow roots and crowns of improved forage crops.
Without that snow barrier, species such as alfalfa and timothy — the most susceptible of our non-native forages — are subject to winter injury, which thins stands. This leaves less competition for weeds to establish and flourish.
Dr. Scott Greiner, Extension Animal Scientist – Sheep, Virginia Tech
(Previously published on the Virginia Cooperative Extension web page)
Creep feeding young lambs while still nursing the ewe can provide valuable supplemental weight gain. This added weight gain has the most economic value for lambs managed in an intensive, early weaning production system where lambs will be maintained in a dry-lot. Conversely, for lambs that will be developed on pasture throughout the spring and summer, creep feeding would be of less value due to the relative expense of this early weight gain. Creep feeding also is beneficial for flocks with a high number of multiple births, or flocks with ewes having limited milk production.
The Lambing and Kidding simulator Workshop originally scheduled for March 16, 2020 has been rescheduled for Monday, October 5, 2020.
More information on registration details coming soon!
Wormboss
(Previously published on Wormboss, Tests and Tools, Management Tools, Grazing Management)
roblem:
Many producers are unaware how long is required to prepare low worm-risk paddocks, although surveys show most are in favor of using them.
Solution:
Understanding the few conditions under which worm larvae will die is vital in creating low worm-risk paddocks.
Benefit:
Knowing the ‘required time’ for your property to create low worm-risk paddocks.
Genevieve Slocum, Kings Agriseeds
(Previously published in On Pasture: February 10, 2020)
Folks have been asking about this recently. From January 2017, Genevieve’s tips can help you adjust your winter grazing now for frost-seeding for a better pasture this summer.
Susan Schoenian, Sheep & Goat Specialist, University of Maryland Small Ruminant Extension Program
(Previously shared on Premier1Supplies Sheep Guide)
Hoof care is an
important aspect of sheep production and management. Hoof diseases can affect the health and welfare of sheep and have a negative effect on productivity. Hooves should be regularly checked for disease and excess growth. Animals which have excessive hoof growth, recurrent hoof problems and/or fail to respond to treatment should be culled.
– Chris Penrose, Extension Educator, Ag and Natural Resources, Morgan County
Originally posted on the BEEF Newsletter
One goal I have had with livestock grazing over the years is to start as soon as I can. I put spring calving cows on stockpiled grass in early March to calve with the hope of not having to feed any more hay. Many years this works but not this year, grass is just starting to grow. The stockpile is about gone and I have started feeding them some more hay but hope to move the group with the fall calving cows this weekend. I then plan on starting a fast rotation around many of the paddocks and hay fields which is actually later than many years.
Originally posted on the BEEF Newsletter
By: Rory Lewandowski, OSU Extension Educator, Wayne County and Mark Sulc, OSU Extension Forage Specialist
Forage stands will begin spring greenup in the next few weeks, especially in southern Ohio. While winter injury in forages is very hard to predict, this winter has presented some very tough conditions for forage stands. This is especially true of legumes like alfalfa and red clover. Producers and crop consultants should be prepared to walk forage stands early this spring to assess their condition in time to make decisions and adjustments for the 2019 growing season.
Originally posted on the BEEF Newsletter– Mark Sulc, OSU Extension Forage Specialist
As cold weather approaches this week, livestock owners need to keep in mind the few forage species that can be extremely toxic soon after a frost. Several species contain compounds called cyanogenic glucosides that are converted quickly to prussic acid (i.e. hydrogen cyanide) in freeze-damaged plant tissues. A few legumes species have an increased risk of causing bloat when grazed after a frost. Each of these risks is discussed in this article along with precautions to avoid them.
Species with prussic acid poisoning potential
Forage species that can contain prussic acid are listed below in decreasing order of risk of toxicity after a frost event:
Species not usually planted for agronomic use can also develop toxic levels of prussic acid, including the following:
It is always a good idea to check areas where wild cherry trees grow after a storm and pick up and discard any fallen limbs to prevent animals from grazing on the leaves and twigs.
Fertility can affect poisoning risk. Plants growing under high nitrogen levels or in soils deficient in phosphorus or potassium will be more likely to have high prussic acid poisoning potential.
Fresh forage is more risky. After frost damage, cyanide levels will likely be higher in fresh forage as compared with silage or hay. This is because cyanide is a gas and dissipates as the forage is wilted and dried for making silage or dry hay.
Plant age affects toxicity. Young, rapidly growing plants of species that contain cyanogenic glucosides will have the highest levels of prussic acid. After a frost, cyanide is more concentrated in young leaves and tillers than in older leaves or stems. New growth of sorghum species following a non-killing frost is dangerously high in cyanide. Pure stands of indiangrass can have lethal levels of cyanide if they are grazed when the plants are less than 8 inches tall.
Toxicity Symptoms
Animals can die within minutes if they consume forage with high concentrations of prussic acid. Prussic acid interferes with oxygen transfer in the blood stream of the animal, causing it to die of asphyxiation. Before death, symptoms include excess salivation, difficult breathing, staggering, convulsions, and collapse.
Ruminants are more susceptible to prussic acid poisoning than horses or swine because cud chewing and rumen bacteria help release the cyanide from plant tissue.
Grazing Precautions
The following guidelines will help you avoid danger to your livestock this fall when feeding species with prussic acid poisoning potential:
Greenchop
Green-chopping frost-damaged plants will lower the risk compared with grazing directly, because animals are less likely to selectively graze damaged tissue. Stems in the forage dilute the high prussic acid content that can occur in leaves. However, the forage can still be toxic, so feed greenchop with great caution after a frost. Always feed greenchopped forage of species containing cyanogenic glucosides within a few hours, and don’t leave greenchopped forage in wagons or feedbunks overnight.
Hay and silage are safer
Prussic acid content in the plant decreases dramatically during the hay drying process and the forage should be safe once baled as dry hay. The forage can be mowed anytime after a frost if you are making hay. It is rare for dry hay to contain toxic levels of prussic acid. However, if the hay was not properly cured and dried before baling, it should be tested for prussic acid content before feeding to livestock.
Forage with prussic acid potential that is stored as silage is generally safe to feed. To be extra cautious, wait 5 to 7 days after a frost before chopping for silage. If the plants appear to be drying down quickly after a killing frost, it is safe to ensile sooner.
Delay feeding silage for 8 weeks after ensiling. If the forage likely contained high levels of cyanide at the time of chopping, hazardous levels of cyanide might remain and the silage should be analyzed before feeding.
Nitrate accumulation in frost forages
Freezing damage also slows down metabolism in all plants that might result in nitrate accumulation in plants that are still growing, especially grasses like oats and other small grains, millet, and sudangrass. This build-up usually isn’t hazardous to grazing animals, but green chop or hay cut right after a freeze can be more dangerous. When in doubt, send a forage sample to a forage testing lab for nitrate testing before grazing or feeding it.
Species That Can Cause Bloat
Forage legumes such as alfalfa and clovers have an increased risk of bloat when grazed one or two days after a hard frost. The bloat risk is highest when grazing pure legume stands and least when grazing stands having mostly grass.
The safest management is to wait a few days after a killing frost before grazing pure legume stands – wait until the forage begins to dry from the frost damage. It is also a good idea to make sure animals have some dry hay before being introduced to lush fall pastures that contain significant amounts of legumes. You can also swath your legume-rich pasture ahead of grazing and let animals graze dry hay in the swath. Bloat protectants like poloxalene can be fed as blocks or mixed with grain. While this an expensive supplement, it does work well when animals eat a uniform amount each day.
Frost and Equine Problems (source: Bruce Anderson, University of Nebraska)
Minnesota specialists report that fall pasture, especially frost damaged pasture, can have high concentrations of nonstructural carbohydrates, like sugars. This can lead to various health problems for horses, such as founder and colic. They recommend pulling horses off of pasture for about one week following the first killing frost.
High concentrations of nonstructural carbohydrates are most likely in leafy regrowth of cool-season grasses such as brome, timothy, and bluegrass but native warm-season grasses also may occasionally have similar risks.
Another unexpected risk can come from dead maple leaves that fall or are blown into horse pastures. Red blood cells can be damaged in horses that eat 1.5 to 3 pounds of dried maple leaves per one thousand pounds of bodyweight. This problem apparently does not occur with fresh green leaves or with any other animal type. Fortunately, the toxicity does not appear to remain in the leaves the following spring.