Bloat has been described in agricultural writings since A.D. 60. Names for bloat have changed over the years: hoove, hoven, tympany, and blown have appeared in English journals of the 18th and 19th centuries.
Bloat occurs when rumen gas production exceeds the rate of gas elimination. The gas accumulates and causes distention of the rumen (left side of cattle). If the situation continues, the inflated rumen interferes with respiration. The problem is worsened by the absorption of carbon dioxide (CO2) from the rumen. Death is normally due to suffocation.
Bloat is often associated with discontinuous grazing, such as the removal of animals from legumes pastures overnight. Pasture bloat may occur when grazing is interrupted by adverse weather, such as storms, or biting flies. Anything that alters normal grazing habits will increase the incidence of bloat. The following are a list of forages and their bloat potential:
Figure 1. Alfalfa stem wilting caused by freezing.
The weather forecast this week is indeed concerning for forage stands in general and especially for alfalfa and red clover. The low night temperatures in the forecast may potentially cause severe frost injury to both annual forage crops (e.g. winter rye and winter triticale) and perennials forages.
Growers should scout and evaluate their forage stands several days after the cold nights because predicting freeze damage is difficult to impossible. Freeze damage and plant recovery from it are influenced by many factors, including the absolute minimum low air temperature, soil temperature during the freeze event that can moderate near-surface air temperatures in the canopy, field topography, snow cover during cold nights (that provides insulation), age and stage of plant growth, and stand health and vigor as influenced by soil fertility and prior cutting management.
The overall vigor of the stand will determine the tolerance to freezing and . . .
In this, ODA’s latest Grazing Management Minute, join Area Resource Conservationist, TJ Oliver, with USDA’s National Resources Conservation Service to learn more about renovating your winter feeding sacrifice areas.
– Garth Ruff, Beef Cattle Field Specialist, OSU Extension (originally published in Farm & Dairy)
A good mineral program is just as important as good forages in a successful grazing program.
The grass is getting greener by the day and the grazing season is within sight. In previous editions of this column my colleagues have covered a variety of topics to consider before turning livestock out to pasture this spring. While checking fences, watering systems, pasture fertility, and forage establishment are often on our minds before spring turnout, another thing we need to consider is our mineral program.
Having a sound, balanced mineral program in place is important throughout the year as minerals are involved in most if not all metabolic functions of our livestock, including growth, reproduction, and lactation. However, it is often on pasture where we run into mineral imbalances and issues. While some issues are harder to detect such as reduced daily gain or lost milk production, others like Continue reading →
In this episode of Forage Focus, Host- Christine Gelley- Extension Educator, Agriculture & Natural Resources in Noble County and OSU Extension’s Beef Cattle Field Specialist- Garth Ruff met in the pasture at the Eastern Agricultural Research Station to offer tips for spring grazing.
In March and April, pasture green-up is an exciting sight, but it does present some challenges for managing both the animals and the forages. Garth and Christine discuss how to know when to turn animals out on fresh grass, the risks of grass tetany, the benefits of high-mg mineral, fly control, renovating winter feeding sites, soil fertility, timely fertilization (or not) and more!
– Victor Shelton, NRCS State Agronomist/Grazing Specialist
Poison Hemlock is already up and growing!
Yes, it’s getting to be that time of year — new spring green growth! The cows start complaining about eating hay and bellowing when they hear my voice or even just see me. It’s not that the hay is any less delectable, it’s just not what they know is available across the fence. It’s about like a kid walking by a candy store; the focus is on the treat.
I’ve listened to several pretty intense arguments over the years on the topic of when to start grazing in the spring. Some spoiled cows are never denied their micro-greens and sadly, the pastures usually show it. I’ve heard some say, “the cows know best.” They do have excellent biological feedback from their stomachs that tells them there is usually more energy and protein in that lush new forage. This is even more true with small ruminants such as sheep and goats who can and will sometimes select specific plant parts because of differences in energy or nutrients that are needed at the time. Perhaps this is the ruminant animals “gut” instinct.
Unfortunately, just like eating too much candy from the candy store, ruminants eating too much lush green cotton candy growth early in the year can have Continue reading →
– OSU Extension Agronomy Crops Team CORN newsletter
Cressleaf groundsel has been a problem in recent years in both forage and row crop fields throughout Ohio.
Now is the time to scout hay and pasture fields for the presence of winter annual and biennial weeds, especially those that are poisonous to livestock such as cressleaf groundsel. These weeds are resuming growth that started last fall and they are most effectively controlled with herbicides while still small. In addition to cressleaf groundsel, weeds of concern that should be treated soon include the following: poison hemlock, birdsrape mustard (aka wild turnip), wild carrot. Herbicides are most effective on these weeds in the fall, but they can be controlled in spring, preferably when still in the rosette stage. Control becomes more difficult once stem elongation (bolting) starts.
– Christine Gelley, OSU Extension Agriculture and Natural Resources Educator, Noble County
The spring seeding window for the most popular forages in our region is quickly approaching. Producers looking for guidance on how to choose the best forage for their system should always start with a soil test rather than a seed catalog. Whether you have farmed your site for decades or days, soil testing is essential for success.
Once you know the characteristics of your soil, you can formulate a timeline to adjust fertility if needed, sow your selected seed, and set realistic expectations for production. Soil testing should be conducted when site history is unknown, when converting from a different cropping system (row crops, woodlands, turfgrass, etc.), or on a three-year schedule for maintenance.
Additional factors worthy of consideration prior to purchasing seed include site drainage, sunlight exposure, weed competition, forage harvest method, and feed value for the end user. Choosing a forage that is adapted to the conditions of the site may be more effective than adapting the site to fit an Continue reading →
– Dr. Michelle Arnold, Ruminant Extension Veterinarian, University of Kentucky Veterinary Diagnostic Lab; A special thanks to Dr. Jeff Lehmkuhler for his contributions to this article.
What is “Grass Tetany” and when are cattle most likely to have it? Grass tetany, also known as spring tetany, grass staggers, wheat pasture poisoning, winter tetany or lactation tetany, is a condition resulting from a low level of magnesium (Mg) in the blood. Maintenance of blood magnesium depends on the amount obtained from the daily diet since the magnesium present in teeth and bones and is not easily mobilized in times of need. Magnesium is required for proper nerve and muscle function so low levels in the blood result in “tetanic spasms” where muscles contract uncontrollably. The disorder in an adult cow begins with separation from the herd and going off feed. The ears are often erect and twitching and the cow is alert, hyperexcitable and may be aggressive. The symptoms quickly progress to muscle spasms, convulsions, difficulty breathing, and death. Often the affected animal is found dead with evidence of thrashing and struggle on the ground around her. Deficiencies occur most often in beef cows when they are nursing a calf and grazing young, green grass in early spring. Fast-growing spring pastures are high in potassium (K+) and nitrogen (N+) and low in magnesium (Mg++) and sodium (Na+) ions. Affected cattle often have low blood calcium concurrently. Fall calving cows may also experience grass tetany during the winter months.
Will Feeding Plain White Salt to Cows Prevent Grass Tetany? This claim is shared every spring and, indeed, there are producers who do not have grass tetany that only feed salt. How can that be? Simply put, for some producers, the minerals available in their soils and forages are enough to meet the nutritional needs of their cows. Regional soil types, soil fertility, diverse forage species and differing cattle requirements based on age and stage of lactation result in different mineral needs for grazing livestock on every farm. A blanket recommendation to just feed salt ignores these factors and Continue reading →
– Dr. Katie VanValin- Assistant Extension Professor- University of Kentucky.
Perhaps it was the full season worth of winter weather we got in one-week last month, or the above average temperatures that followed, but either way we are rounding the bend and spring will be here before we know it. One of the things I love most about spring is that along with the warmer temperatures and longer days, inevitably comes greener pastures. However, the growth we see out in our pastures during the early spring can often be deceiving from a nutrient standpoint.
The problem that we can run into is that there simply is not enough forage available, and the forage that is high in moisture. When we turn cows out to early, they can exert more energy searching for the next mouthful then they are consuming, since most of every mouthful is water. This is especially critical for spring-calving cows. At this time, cows have either or will be transitioning from late gestation to lactation which represents the time when a cow’s maintenance nutrient requirements are at their highest throughout the production cycle. This is not the time to let cows slip into an energy deficit and lose condition.
If cows lose condition during early lactation when their maintenance nutrient requirements are high, it is often difficult to recover that condition prior to breeding. It is a much better plan to Continue reading →