K-State Research and Extension

“Forage Analysis: What Numbers Do I Need?”

By: Justin Waggoner, Ph.D., Beef Systems Specialist

One of the more common questions I receive with regard to analytical testing of forages and other feedstuffs is “I have the sample, now what do I test for or what analysis package should I select?”

The basic components that nutritionists need to evaluate a feedstuff or develop a ration are dry matter or moisture, crude protein, an estimate of the energy content of the feedstuff (Total Digestible Nutrients (TDN), Net Energy for Maintenance (NEm), Net Energy for gain (NEg), and the macro minerals, Calcium and Phosphorous. These are the most basic numbers that are required, but including some additional analyses in the report can give us additional insight into the quality of the feedstuff or improve our ability to predict animal performance, which is the primary reason we analyze feedstuffs. I recommend that the report include acid detergent fiber (ADF) and neutral detergent fiber (NDF). The amount of NDF in forage reflects the amount of cell wall contents (hemicellulose, cellulose, and lignin) within the sample. The NDF fraction is often associated with the respective bulkiness of forage and is correlated with dry matter intake of the forage or feedstuff. Therefore, the amount of NDF may be used to estimate the expected dry matter intake associated with the forage. The ADF number represents the amount of cellulose and lignin within the forage and is correlated with the respective digestibility of the forage. In general, a higher ADF value is associated with forage that has a greater proportion of cellulose and lignin and would likely be more mature. Additionally, the ADF fraction is used to calculate the energy estimates TDN, NEm, and NEg that appear on the report. There are a number of different mathematical equations that the testing laboratory may use to calculate these numbers, based on the type of sample (corn silage, alfalfa, grass hay, etc.). If the ADF is included in the report, the nutritionist can adjust or recalculate the energy estimates if necessary.

If the forage will be fed in combination with a byproduct feed, such as wet distiller’s grain, including an analysis for sulfur can be beneficial if the forage will be used in a growing or feedlot ration. Additionally, if the forage is a known nitrate accumulator (forage sorghums, sudangrass) or may have been stressed due to drought, including a nitrate analysis should always be considered, especially if the forage will be fed to pregnant cows.

Most analytical laboratories have a number of different analysis packages which encompass the most common procedures or numbers that a nutritionist or producer needs to know about their feeds. These packages will typically include the basic procedures (DM, CP, TDN) and then add on specific analyses such as NDF or the Macrominerals (Ca,P, Mg, K, Na, Cl, S). Some laboratories may group analysis packages by the type of sample (Forage vs. mixed ration) or production purposes (dairy vs. beef).

The objective of analytical testing of forages and feedstuffs is to improve our ability to meet the animal’s nutrient requirements and ultimately predict animal performance. The unequivocal best method of evaluating the quality of a feedstuff is feeding the feedstuff to an animal and evaluating performance over a set period of time, under a specific set of conditions. Since that would not be cost effective or timely, analytically evaluating feedstuffs in a laboratory is the next best thing and although it is not perfect, it is unequivocally better than the “this looks like really good stuff” method of evaluating feedstuffs.

For more information, contact Justin Waggoner at jwaggon@ksu.edu.

“Historical Perspective on Cull Cow Prices”

By: Justin Waggoner, Ph.D., Beef Systems Specialist

The sale of cull animals is one of the primary sources of revenue on a cow-calf operation, contributing 17- 24% of the gross income reported by cow-calf operators within the Kansas Farm Management Association from 2013-2017. The figure below offers some historical perspective on cull cow prices in Kansas (LMIC, compiled by Robin Reid). Cull cow prices are seasonal, being lowest in the months of October, November, December, and typically increase in March and then remain steady during the summer months.

The relative difference between the market low and high, based on the 5- and 15-year average prices illustrated in the graph is approximately $10-$15/cwt. Thus, the market value of a cull cow increases $10- $15/cwt. from November to March. A 1,300-lb. cow sold in November at $40/cwt. would generate $520 while the same cow, if sold in March at $55/cwt., would generate $715, a difference of $195.

Although, the cull cow market has been relatively soft in 2019 and we cannot foresee what the market will be in 2020, the historical data indicates that cull cow values typically increase over the winter. The question then becomes whether the increase in value is substantial enough to justify holding onto those cows for an additional 120 days.

For more information, contact Justin Waggoner at jwaggon@ksu.edu.

“Some Thoughts on Calf Revenue”

By: Justin Waggoner, Ph.D., Beef Systems Specialist

The air is now crisp in the morning and it won’t be long before we see the glimmer of ice crystals in the water tank. Many producers are weaning and will be marketing calves in the coming weeks and months. Margins in the cattle industry and agriculture in general are often unfortunately narrow and this year is no exception. Maximizing calf revenue is important for cow/calf producers every year, but is even more important in year’s where the probability of loss is greater than profit. Calf revenue from my academic perspective is driven by 3 factors, 1.) the number of calves sold, 2.) sale weight of calves and 3.) price received. Cow/calf producers to some extent have control over the number of calves sold and sale weight. The number of calves sold is essentially a function of stocking rate, cow fertility and/or reproduction on an operation. The sale weight of calves is more complex but is a multi-factorial combination of genetics, calving distribution, calf age, nutrition, management and technology use (implants). Price received is likely the most influential of the 3 factors that drive calf revenue and is the factor that cow/calf producers often believe they have the least ability to control. Once a set of calves, enters the sale ring, or appears on the video screen their value is determined by what 2 prospective buyers are willing to pay. Although it is impossible for producers to directly influence what buyers are willing to pay, I would argue that they are not completely helpless. Cow/calf producers directly control what they will sell (weaned calves, value-added calves or feeders), and determine when they will sell. These are difficult, complex decisions, that shouldn’t necessarily be made based upon weekly cattle sale reports or the thoughts of your favorite livestock market commentator. I am not saying that keeping informed about current market conditions isn’t important. However, that information when used with resources like Beef Basis (www.beefbasis.com) that use data to evaluate different market scenarios, from selling 6 weight calves the first week of December, to 7 weights in February helps producers make the best decision for their operations. Producers also control what information or data they pass along to the new owner. We all know that data has value in today’s world. I like to compare marketing calves to selling a beautifully restored pickup. If you were selling a pickup, you would share with a prospective buyer every bit of information you had and the details of the process, from the atmospheric conditions when the truck was painted to the actual sales invoice from 1972. Why should selling a set of calves be any different? Value added programs and certified sales provide potential buyers with some degree of assurance that your cattle were managed within the guidelines of the program. If you don’t participate in a defined program, providing the auctioneer or sales representative with as much information as possible about your cattle only helps them do their job better which is to get best price for your cattle.

For more information, contact Justin Waggoner at jwaggon@ksu.edu.

“Silage Harvest is Underway; Be Safe”

By: Justin Waggoner, Ph.D., Beef Systems Specialist

One of the busiest, most fast paced operations that occur this time of year is silage harvest. Cutters and choppers in the fields, trucks racing from the field to the pile or bunker, multiple tractors pushing and packing silage. The speed at which we can harvest silage today is amazing, but we should never allow the speed at which can accomplish a task to compromise safety. Below are a few things to think about during this year’s silage harvest.

• Don’t become complacent. Stay aware of your surroundings. Let’s face it: there are a lot of highly repetitive operations in putting up silage. One of the number one factors that lead up to an accident is complacency, or lack of situational awareness.
• Truck drivers should always slow down when approaching houses and intersections on all roads, every time. Those houses along the road belong to our neighbors and friends, some of which have children. The increased traffic on gravel roads creates dust, and the crops are tall, both of which reduce visibility at intersections. Our neighbors should not fear going to their mailbox due to our silage trucks.
• People (especially children) should never be allowed near a drive-over pile or bunker silo during filling. If people have to approach the area, get on the radio to inform the drivers/operators that people are on foot. Those on the ground in the area should always wear a bright colored safety vest.
• Never fill higher than the top of the bunker wall. This happens more than it should and creates a dangerous situation from the day the silage is packed until it is removed. The pack tractor cannot see the edge of the bunker well, if at all. The silage does not get packed well (which leads to poor silage) and the edge of the silage is unstable and more likely to collapse. Don’t do it.
• Be aware of steep slopes. To reduce the risk of tractor roll-over, a minimum slope of 1 in 3 on the sides and end of piles should be maintained.
• Never inspect or make repairs to equipment near the bunker or pile. Equipment should be removed from the area as soon as possible. Repairs almost always involve people on foot and potentially people who may not be familiar with silage activities and the associated risks.

For more information, contact Justin Waggoner at jwaggon@ksu.edu.