Supplementation varies in summerWritten by Emilee Gibb
As producers are transitioning to summer grazing programs, several factors should be considered, including whether to use a summer mineral program.
“I think there’s probably more emphasis put on the winter mineral program in many cases. I think there’s the potential to have a different mineral program in the summer,” says University of Wyoming Beef Extension Specialist Steve Paisley.
Many producers elect to use a generic mineral program throughout the year. Depending on the time of year, the use of different forages at different stages of production within the cowherd may mean different mineral requirements.
“In the summer, our cows are out on green grass. Typically their mineral requirements are met so we wouldn’t have to address them nearly like we do in the winter months when we’re grazing dormant forages,” continues Paisley.
Producers may often be able to transition to a summer mineral program after breeding requirements have been met.
“I think after breeding, if we have any type of artificial insemination (AI) program, or certainly once we turn cows out on summer grass, especially initially, just providing a good mineralized salt at that time is key,” notes Paisley.
“It’s hard to be generic in designing a program because every location and operation is a little bit different,” laughs Paisley.
Traditionally, Wyoming soils are low in the minerals zinc and copper. As such, most operations will have a baseline requirement that needs to be met year-round. However, it is beneficial for producers to know any specific requirements for their operation.
“Some locations have different issues, like high sulfur or high iron that competes with copper, making the copper requirements go up,” says Paisley.
It is also important to consider that there may be different requirements within different locations of one operation, such as water sources.
“Typically depending on our location, our water sources during the summer months may be utilizing stock ponds,” notes Paisley. “We may be utilizing water that has a different mineral balance than what we were using for well water in the winter months.”
While many requirements may be lower during the summer months, there are still important periods of time to provide a strong mineral program.
“We will have situations and things we want to address. Certainly we’ll want to have a good mineral program in place going into weaning. We want to have calves healthy that are able to withstand a disease challenge,” emphasizes Paisley.
It may be beneficial for producers to consider using different mineral programs for the different age groups of cattle to provide for production requirements.
“Certainly providing mineral to the cow/calf pairs would be more important than providing it to the summer yearlings or replacement heifers that aren’t weaning a calf,” says Paisley.
While the cows may not have high mineral requirements during weaning due to high-quality forage production, it may be useful to provide a complete mineral supplement to the pairs to improve weaning success.
“In my mind, we want to provide mineral more for the calf than for the cow in many cases. I think it’s important to provide a total mineral package to those pairs just because we’re weaning those calves,” Paisley says.
“In general terms, we regulate mineral intake with salt,” notes Paisley.
Cattle typically don’t recognize a need for minerals such as calcium or potassium but will self-regulate their salt needs.
Producers may need to change how they are feeding minerals to the herd during summer months if they were utilizing lick tubs.
“In many cases, in the fall and winter months when we’re utilizing lick tubs, the minerals are provided. We don’t provide any type of compressed molasses or lick tub during the summer months,” cautions Paisley.
If feasible, he recommends using loose salt to supplement minerals, as it is easier to regulate and manage. However, other factors should be considered in choosing how to supplement.
“I know, in many cases, for producers who have Forest Service or BLM allotments, it’s difficult to carry loose mineral up in different locations. In those cases, a lot of the time we have to rely pretty heavily on block mineral,” comments Paisley.
Feeding rates: Feed analysis helps avoid over- or under-feeding livestockWritten by Gayle Smith
With abundant forage supplies expected this year, producers can afford to be more selective purchasing their winter feedstuffs. Despite cheaper prices for hay, livestock ranchers should still have a forage analysis conducted so they can get the most bang for their buck.
Hay producers may also want to consider having a hay analysis completed to use as a marketing tool in a buyer’s market.
According to Rick Rasby, Extension beef specialist with the University of Nebraska, producers would be surprised how much forages can vary in nutritional value.
Rasby discussed samples he had taken at a stack yard on alfalfa and native grass hay.
“We sampled a stack yard of alfalfa, and it ranged from 13 percent to 23 percent crude protein. The native hay ranged from four percent to ten percent crude protein,” he explained.
The National Research Council (NRC) requirements suggest alfalfa averages 15 percent crude protein and 56 percent total digestible nutrients (TDN), and native hay typically averages six percent crude protein and 52 percent TDN.
If a forage has 52 percent TDN, it will be difficult for that forage to meet the cow’s nutritional requirements after calving by feeding it alone.
“As we move closer to 56 percent TDN, the forage may be able to meet the cow’s nutrient requirements prior to calving, but we may need to add a little energy after calving to meet her nutritional requirements because they will be higher,” he explained.
“What is important to note from all of this, is not all forages are average,” Rasby continued. “That is why it is important to get our forage analyzed and why it is important to collect a good sample.”
Taking the sample
Producers can access videos through the University of Nebraska’s YouTube channel, NU Beef, to learn how to sample hay. These videos show samples being taken from a big round bale, and from a pile of ground hay. They also give step-by-step instructions for the sampling process.
“It is very important when sampling hay to get a representative sample,” Rasby explained. “Don’t take grab samples on forages.”
“Producers will need to use a hay probe, which can usually be borrowed from their local county Extension office,” he explained.
Rasby said if a producer has 20 to 25 big round bales of hay, 10 to 12 of those should be sampled to get a good, representative sample. When sampling hay, never sample first, second, third and fourth cuttings of hay together.
“All of those should be separate samples,” he said. “Early cut and late cut hay should also be sampled separately, as well as different varieties like sorghum-sudan grass hay and millet hay.”
After the samples are taken, it is important to identify the sample properly, so the lab analyzing the sample has a good understanding of what is in the bag.
“The forage analysis will only be as good as the sample we have taken,” he said.
Typically, most forages are analyzed in the lab using near-infrared spectroscopy (NIR), which is a quick and accurate way to identify the nutrients in the forage.
Results can typically be received within two to three days of sending a sample in, if producers send it at the first of the week.
Effective supplementation brings together biology, economics on the ranchWritten by Saige Albert
Supplementation is about providing cattle with the necessary nutrients to provide for growth and production, but South Dakota State University Ruminant Nutritionist Ken Olson adds that it is also important for producers to make sure they are getting the biggest benefit for their expenditures.
“There are two aspects we need to think about with supplementation,” Olson says. “First is the biology of the cow’s production, and the other aspect is the buck itself in terms of the economics of pricing potential supplements.”
He adds, “Both of these are really important to maximizing the value of our supplementation program.”
Biology of supplements
“We don’t need to supplement the cows in a green grass pasture situation,” Olson says. “We are talking about supplementing cattle on dormant, fully mature forage.”
Cows grazing dormant, mature forages during the winter months may not receive the nutrition they need. These forages are frequently very low quality.
“When we are talking about low-quality forages, the age old rule is that a forage with seven percent crude protein content or lower is what we are talking about,” he explains. “All dormant forages are not created equal.”
“When we talk about an average of seven percent crude protein in low-quality forages, that creates the first deficiency we need to talk about today,” Olson adds.
When plants are preparing for winter, they store many of their soluble nutrients in the roots to be saved for the upcoming years, leaving primarily fiber in the above-ground portions of the plant.
“Ruminants can digest fiber and use that as their primary energy source,” Olson says, “but we have to make sure the cow has the capacity to digest the fiber and use it.”
When referencing the capacity of the cow, Olson explains that a cow will eat forages, which move through the esophagus into the reticulum - the first compartment of the four-chambered stomach. After passing through the reticulum, forages are digested in the rumen.
“The feed stays in the rumen until particles get small enough to fit through the omasal orphus, which is the opening into the third compartment of the stomach,” he says. “The feed stays in the rumen until she can get as much of the nutrients out of it as she can. Sometimes, as we’re going to learn with low-quality forages, that can take a long time.”
When the rumen of the cow is full, she stops eating until it empties and more capacity is available. Receptors in the stomach work similarly to a float valve in a tank.
“With low-quality forages, it takes longer for the rumen to empty, so the rate of digestion passage slows and the quality of digestion goes down,” Olson comments. “Digestibility gets cut nearly in half as we go from our best forages to our worst forages, and intake gets hurt.”
Research shows that nearly a three-fold decrease can be seen on the amount of forage consumed as a percentage of body weight, which means that the cow is gaining less and producing less as a result.
Choosing a supplement
After it is determined that a supplement is necessary, Olson explains that choosing a supplement is important.
“We know we are deficient of some nutrients,” he says. “”We need to provide additional nutrients, but we can’t afford enough supplement to meet all of those. We have to help the cow do a better job of getting more fiber, and we need to overcome the limitations of digestion and intake.”
One key method to help a cow’s digestive system is to help the microbes in her cut.
“When we are feeding a cow, we are feeding for two,” Olson says, “and I’m not talking about her calf. I’m talking about the ruminant microbes. We need to meet their requirements first if we have a ghost of a chance of meeting the cow’s requirements.”
The definition of a seven percent crude protein requirement feeds the microbes in the cow’s gut. As a result, protein above that is necessary to supply the cow’s needs.
Supplements are classified based on their protein content. Protein supplements are high in protein while energy supplements are low in protein.
The ratio of protein to energy is also important, and Olson explains that protein is the first limiting nutrient in many situations.
“If we provide more protein, microbes can feed, digest it and use that to grow more microbes,” he explains. “If we can grow more microbes, the cow can digest more fiber and she can increase the rate that she digests quite dramatically.”
Interactions among feeds can affect the nutritional value of forages.
“We can increase nutritional value of a forage by adding protein in the form of supplement,” Olson adds. “We can also cause negative associative effects.”
For example, grains are more efficiently digested than fiber. A grain-based energy supplement can be detrimental.
“Grains are mostly starch, and when starch competes with fiber to be digested, starch wins the war every time,” Olson explains. “If we overcome the protein deficiency, we can’t grow more microbes.”
At the same time, microbes will preferentially digest starches, leaving more fiber in the gut and further slowing digestion.
“The interaction of the feed combination is important,” he summarizes. “When we add one feed in combination of another, we can press the quality out of one we hope to get more out of.”
When seeking supplements, Olson also noted that producers must consider the cost per pound of crude protein, as well as the cost of transportation. He also urged producers to ensure they aren’t paying for unnecessary water.
“We need to evaluate our supplements on a crude protein basis, and we need to get them on the same dry matter content,” Olson said. “There are a variety of feeds, and we have to calculate the price per ton of crude protein.”
For example, he explained that in all his calculations over 30 years as a nutritionist, cake with 30 percent crude protein is always cheaper on a crude protein basis than 20 percent range cake.
At the same time, he also adds that tubs tend to be more expensive than any other crude protein sources, but he cautions producers, “There are reasons that we may use tubs. Sometimes, there are other reasons that supplements can be valuable, such as for improved pasture distribution or cost of hauling.”
Olson spoke during the 2015 Range Beef Cow Symposium, held in mid-November in Loveland, Colo.
Mineral programs with copper recommended for cattle on Wyoming rangelandsWritten by Natasha Wheeler
A balanced mineral program can be complex, and each situation should be evaluated carefully when issues arise. In Wyoming, copper is one of the minerals that can become deficient in the diets of grazing cattle.
“Copper is a trace element that is important for cattle. It’s important for the immune system and for metabolism,” comments Steve Paisley, University of Wyoming Extension beef specialist. “Copper and zinc are probably the two trace minerals that western rangelands are typically deficient in.”
Most commercial mineral programs include some levels of copper, although there are a few points throughout the year where adequate levels may be especially important, such as calving through rebreeding and prior to weaning.
“Making sure we have good adequate mineral available to our animals 60 days before weaning is key because copper is so important from an immune status standpoint,” he mentions.
Looking for deficiency
Traditionally, a copper deficiency could be recognized by a reddish tint in an animal’s hair color, but that may not always be an accurate indicator.
“My approach is to look for anything out of the ordinary,” notes Paisley.
Abnormally high levels of illness, low rebreeding rates, poor calf health or other issues that don’t seem to be related to poor nutrition or management may be signs of imbalances in mineral intake.
“An initial way to test for deficiency is to sample the forages,” he says. “When we do that, we try to mimic the diet the cattle are taking in, so we can test the forages and evaluate whether they are meeting nutritional requirements.”
Paisley suggests sampling the top third of grazed forages, which is the portion of the plant that the cattle typically eat. Samples should also be collected in areas where the animals usually graze and include the desirable species that are normally ingested by the cattle.
“We should also probably test the water to get a good idea of whether or not our mineral program is complete,” he adds.
If forage and water samples fail to provide a better understanding of mineral issues, liver biopsies can also be used to help evaluate copper levels in the herd.
“Liver biopsies involve making a small incision on the side of the animal and using a hollow needle to remove a small tissue sample with minimal impact to the animal,” he describes.
Because challenged animals can sequester copper, Paisley recommends sampling healthy animals from the main herd to ensure accurate results.
In Wyoming, one of the issues producers also run into is a secondary deficiency. A secondary deficiency occurs not when copper levels are too low but when competing mineral levels are too high, making it difficult for animals to absorb the copper.
“We can run into that with iron, high sulfur or molybdenum. By forage sampling and testing the water, we can get an idea of whether or not we have adequate copper and also if we have other elements that may be competing with copper and causing a secondary deficiency,” Paisley explains.
If one of these issues is detected, a mineral program with adequate copper levels may be sufficient, although a more extreme case may require looking into copper sources that are easier to absorb.
“Minerals that have compounds attached to them, know as organic or chelated minerals, cause more complete absorption,” he mentions.
Chelated minerals have been combined with organic compounds to create complexes, and they represent one of the many kinds of sources that increase the biological availability of minerals for livestock.
In Wyoming, too much copper isn’t much of a concern in cattle, but sheep are another story.
“While sheep still have a requirement for copper, they tolerate much lower levels than cattle do. We can’t feed a cattle mineral to sheep without some major issues because sheep have a real toxicity problem with copper,” warns Paisley.
Producers who place mineral in areas where sheep may have access to it should exercise extra caution to prevent harming the sheep.
Paisley also suggests looking for a second opinion when mineral deficiency or secondary deficiency issues arise.
“What’s available, what’s absorbed and any interactions that may exist – those are all important things to consider. It is good to have a few opinions from other people to help make those decisions,” he comments, adding that local veterinarians, nutritionists and university or Extension personnel are always good sources for producers seeking more information.
Improvements in commercial cow/calf forage efficiency found to be smallWritten by Natasha Wheeler
“Cattle have been put under extreme selection pressure for one trait or another. The question is, over time, are we getting closer to cattle that better match our forage resources?” asked Oklahoma State University Extension Beef Cattle Specialist David Lalman.
To investigate, he considered a list of factors that would indicate efficient cows, including early sexual maturity, a high rate of reproduction, low rates of dystocia, longevity, minimum maintenance requirements and the ability to convert forage resources to pounds of beef.
“It’s a good exercise to ask whether we’ve improved in any or each one of those characteristics,” he noted.
Lalman and his team gathered data from the Kansas Farm Management Association, the Cowherd Appraisal Performance Software (CHAPS) Summary in North Dakota and the Standardized Performance Analysis (SPA) Summary involving New Mexico, Oklahoma and Texas. The data was specific to commercial cow/calf operations and did not include seedstock or purebred operations.
“The idea was to find data that represented moderate- to low-input operations,” he explained.
To begin, the research team reviewed simple indices for weaning weights across the operations. Data from the southwest region suggested that weaning weights have not changed significantly over the last 20 years.
“If we look at the Kansas data, we might argue that there was a sustained increase in weaning weight of about 15 or 20 pounds, but since 2002, that has actually been flat or even trended downward. North Dakota data looks like there was some variability early on, with perhaps some slight improvement in weaning weights over a long period of time,” Lalman commented.
Taken together, the data sets don’t show significant increases in weaning weights over the last 20 to 25 years.
“Considering the selection pressure of the industry, that’s somewhat of a surprise,” Lalman stated.
The research team also looked at milk production in beef cattle, noting there is a high demand for energy and protein for milk production in cows.
Comparing several different breeds over the last 23 years, the team noticed that most breeds have increased milk production through aggressive selection pressure.
“Milk production comes at a cost, and the year-long maintenance requirement is increased as well,” Lalman said, explaining that high milking cows require higher maintenance costs, even when these cow are dry.
“It’s related to the increased maintenance requirements related to greater visceral organ mass relative to empty body weight. Visceral organ mass is the rumen, small and large intestine, liver, heart and kidney. Of course, those are all very metabolically active tissues, and they are very expensive tissues to maintain,” he said.
According to published studies the Lalman reviewed, cows with moderate to high milk production that are then selected for higher milk production create cows with good yields but also greatly increased conversion factors, meaning that it takes more pounds of feed per pound of milk to produce those high yields.
“Beef producers need to ask themselves whether there is a limit of milk production their forage can support,” stated Lalman.
To illustrate his point, he explained that a dairy cow may have a high milk yield in her environment at the dairy with high-energy feed, but if that same cow were to be sent out onto the range in Oklahoma, her milk production we be reduced dramatically.
“There’s a limit to the amount of milk yield that the native rangeland in Oklahoma can support. Everyone’s forage has a limit. I’m guessing that perhaps we have met and exceeded that limit in many cases already,” he remarked.
He continued, “I think there’s increasing risk or frequency of cases where forage resources limit the expression of genetic potential for milk and/or production costs have increased because the environment has been artificially modified to fit the cow.”
According to his research, Lalman was surprised to find there was not strong evidence showing that commercial cow efficiency has improved when considering efficiency in a “sell at weaning” context.
“Moderation in genetic potential for milk yield should reduce enterprise risk and improve fertility due to a better match between forage nutritive value and beef cow requirements,” he concluded.