This article comes to us from Aaron L. Berger, Extension Educator, and Rick N. Funston, Beef Reproductive Physiology Specialist, both from University of Nebraska Extension. In the past several decades, post-weaning development of replacement heifers has focused on feeding heifers to reach a target body weight of 60 to 65 percent of mature weight at…
at breeding to achieve acceptable pregnancy rates (85 to 95 percent) in a breeding season that ranges from 45 to 70 days. This development system was based on historical research that indicated heifers bred at approximately 14 months of age should reach this target weight to achieve acceptable pregnancy rates.
In an effort to reduce costs, recent research has focused on comparing traditional, more intensive replacement heifer development systems to systems utilizing more inexpensive feed resources to develop heifers to lighter target body weights at breeding (i.e., 50 to 57 percent of mature weight compared with the traditional 60 to 65 percent of mature weight). Research has demonstrated replacement heifers developed to lower target weights — but on a positive plane of nutrition before the breeding season through calving — can have acceptable pregnancy rates and longevity.
These lower-input systems allow producers to develop replacement heifers at lower cost without sacrificing reproductive performance. This publication highlights why recommended target weights for replacement heifers have changed and key aspects of successful low-input replacement heifer development systems.
Why Recommendations for Heifer Target Body Weight at Breeding Have Changed
Much of the research recommending heifers be at a target weight of 60 to 65 percent of mature weight by breeding was conducted from the late 1960s through the 1980s. Since then, the genetic makeup of the U.S. cowherd has changed significantly. Age of puberty does not seem to be limiting heifer development programs as it did in the past. Heifers are reaching puberty at younger ages and at a lower percentage of their mature weight than has occurred historically.
Research contributing to this publication was conducted using current British and Continental genetics in the United States. The following genetic trends have been realized by widespread management changes and the use of Expected Progeny Differences (EPDs) in the selection for a variety of traits, including scrotal circumference and yearling weight.
Imagine you’re a carbon molecule floating in the atmosphere and your mission is to get from there into the soil and stay there for decades. Your first step – slip into a plant through an open stoma. Stomata are microscopic openings on the surfaces of plant leaves that allow for the easy passage of water […]
A bad habit that many grass managers have in lawn and hay systems is cutting it too close. By “it,” I mean the grass. There are some misconceptions about what the best height is to cut grass. It can also be confusing because the ideal cutting height varies with the type of grass. The common […]
While there are many grazing systems, there are fundamental questions related to pasture management that are common to all of them: 1. How does residue height of vegetative grass influence pasture growth? 2. How does mob-stocking of mature grass influence pasture growth? 3. What is the effect of early grazing in the spring when grass is still short? […]
Ten years of work result in the discovery of the gene that allows plants and mycorrhizal fungi to interact and could lead to plants that require less fertilizer and can survive and thrive in arid environments.
A team of scientists led by the Department of Energy’s Oak Ridge National Laboratory have discovered the specific gene that controls an important symbiotic relationship between plants and soil fungi, and successfully facilitated the symbiosis in a plant that typically resists it. The discovery could lead to the development of bioenergy and food crops that can withstand harsh growing conditions, resist pathogens and pests, require less chemical fertilizer and produce larger and more plentiful plants per acre.
Scientists in recent years have developed a deeper understanding of the complex relationship plants have with mycorrhizal fungi. When they are united, the fungi form a sheath around plant roots with remarkable benefits. The fungal structure extends far from the plant host, increasing nutrient uptake and even communicating with other plants to “warn” of spreading pathogens and pests. In return, plants feed carbon to the fungus, which encourages its growth.
BISMARCK – “Anthrax has been confirmed in a group of cows in a pasture in east Billings County,” said North Dakota Agriculture Commissioner Doug Goehring. North Dakota’s state veterinarian says the state’s first reported case of anthrax this year is a reminder to livestock producers to take action to protect their animals from the disease, […]
This article comes to us from Steven Shafer, Ph.D., the former Soil Health Institute interim chief scientific officer and retired soil microbiologist the Noble Research Institute.
Fire affects many important ecosystem processes. Much of what we understand about the impact of fire on terrestrial ecosystems comes from many decades of research on the effects of forest and prairie fires on plant communities and succession, nutrient cycling, erosion, and soil properties.
Soil itself is a complex ecosystem that supports all living things above ground. Soils also host an incredible diversity of bacteria, fungi and other microbes that are affected by various factors such as soil nutrients, seasonal changes, drought, pH, chemical applications, plant species and farming practices. Although many microbes are adapted to high-temperature environments (we’re all fascinated by reports of weird microbes growing right at the edges of geysers and undersea vents), no physiologically active microorganism can survive fire.
However, we’ve learned that fire is a powerful regenerating force. This is why prescribed burns are useful management tools in forests and rangelands to clear out old growth, stimulate new growth and recycle nutrients.
We can see benefits of fire on plant communities that rebound from dormant seeds and surviving roots, but there are pluses for the unseen as well. The microorganisms that are killed by fire near the soil surface, where temperatures are greatest during a fire, become food for the survivors that escape by living deeper down or by being protected within the occasional soil aggregate (bound-up clusters of soil particles that may encase microbes and protect them from high temperatures).
The duration and intensity of the peak temperature is what affects the soil organisms most. If it gets hot enough, the soil can actually be sterilized, at least in the top few inches. Emissions of carbon dioxide normally rising from the soil microbes may be briefly suppressed due to the reduced population.
Some of the most sensitive microbes are the mycorrhizal fungi, which are adapted to a symbiotic (literally “living together”) relationship with plant roots. The fungi may be reduced near the soil surface, where new plant roots eventually take hold. Those plants may struggle at first, in the absence of these fungi that aid in nutrient uptake. But the microbe population will recover once the heated soil cools down and microbial cells and spores re-enter on wind and in water. Cycling of nutrients ramps up fast, and their availability to newly emerging plants allows recolonization to begin.
Forage sampling in a standing pasture allows us to get a feed value estimate of forages that will be fed to livestock. It’s also helpful for making sure your forage is at the best stage for cutting hay. While you can look at it, checking the color, leaf to stem content, and the stage of […]
If you go to enough workshops about grazing, you’re bound to see an illustration that shows how biting off the tops of plants impacts their roots, and how if you graze short enough, the plant won’t have enough roots to rebound and produce more leafy material. In fact, if you’ve been with us at On Pasture for any length of time, you’ll have seen a version of that illustration.
First off, let me assure you I do not hate horses. In fact, this article is not really about horses at all. It is about soil and grass.
Horses, though, can really improve grass and soil even though the way they are currently managed does the opposite. It’s just that when horses are grazed in a group with cattle, sheep, and hogs (what I call a MOB), they have some peculiarities as does each species I have dealt with.
There appears to be a hierarchy of species when they are combined. Saddle horses tend to have an air of aristocracy above all others. It’s not even all horses; just saddle horses. For some reason, being trained changes a horse’s perception of itself because I have not seen this behavior when grazing bucking horses.
Cattle, on the other hand, are pretty easy going and are content with good grass and clean water. They do not, however, appreciate pushy sheep. Yes sheep are pushy! They butt to the front of the line and don’t observe proper social etiquette. For some reason sheep don’t take the hint when a cow bunts them out of the way. Hogs can be that way as well, but are actually the social butterflies of the MOB. They don’t really care who they hang out with as long as there is good grass to eat. Side note: turkeys have not fared well grazing with larger animals. The economic loss from irate cows and curious hogs made me abandon adding them to the MOB quickly! Maybe someone else has been successful, but it wasn’t me.
When putting a multi-species MOB together, the first two weeks is when you see these behaviors amplified. The saddle horses will do things like block a gate after the MOB has been nicely flowing for a quarter mile. As a herder, you will be in the back wondering why the whole MOB has stopped. You glance up to see your favorite saddle horse turned sideways in the gate blocking any animal from passing. It becomes your job to ride to the gate and chase that horse through the gate with a stick, rock, or something hard to get your point across. Like I said, horses are jerks! Maybe I am being a bit too hard on horses because I have had a couple bulls do the very same thing.
For the MOB to work effectively, it requires a strong leader. YOU must become that leader. If there are bunch quitters you must harass them and teach them the MOB is their safe place. It doesn’t matter what species or what age. Each animal must know they are safe as long as they stay within the MOB. If an animal is blocking a gate you as the leader must let that animal know it is unacceptable behavior. If a cow keeps bunting sheep away from the water you must get after that cow. It may be difficult if the horse blocking the gate is a pet to you. Out in the MOB there are no pets, only equal members of the MOB. So suck it up and be a strong leader! (Here’s the technique I use to teach my animals that “Happiness is Being in the Herd.”)
After the initial training phase is over, you will see amazing things happen within the MOB. The animals learn they are part of one unit. It doesn’t matter what species they are. You can still sort off the animals you want, however, if you happen to bring in only the cattle or only the sheep, you may turn around to find that the rest of the MOB is following. Even the horses!