K-State Research and Extension

Winter is here and most cattle producers appreciate that cold weather increases nutrient requirements. However, what increases and by how much?
Cattle are most comfortable within the thermonuetral zone when temperatures are neither too warm nor cold. The upper and lower boundaries of the thermonuetral zone are referred to as the upper and lower critical temperature. During the winter months cattle experience cold stress anytime the effective ambient temperature, which takes into account wind chill, humidity, etc., drops below the lower critical temperature. The lower critical temperature is influenced by both environmental and animal factors including hair coat and tissue insulation (body condition). The table below lists the estimated lower critical temperatures of cattle in good body condition with different hair coats. In wet conditions cattle can begin experiencing cold stress at 59°F, which would be a relatively mild winter day. However, if cattle have time to develop a sufficient winter coat the estimated lower critical temperature under dry conditions is 18°F.

Cold stress increases maintenance energy requirements but does not impact protein, mineral or vitamin requirements. The general rule of thumb (for a cow in good body condition, BCS = 5 or greater) is to increase the energy density of the ration by 1% for each degree (Fahrenheit) below the lower critical temperature. The classic response to cold stress in confinement situations is an increase in voluntary intake. However, it has been documented that cattle maintained in extensive environments (native range, wheat pasture, corn stalks) may spend less time grazing as temperatures decline below freezing, which reduces forage intake (Adams et al., 1986) and makes the challenge of meeting the cow’s nutrient requirements even greater. In many cases feeding a greater amount of low-quality hay will replace grazed forages but may not provide sufficient energy. Therefore providing additional energy by feeding a higher-quality hay or fiber-based supplement (DDGS, Corn gluten feed, or Soybean Hulls) may be required.

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

Previously in this column I have discussed calf revenue, which is principally driven by 1) the number of calves marketed 2) sale weight of calves and 3) price received. Now I would like to examine the other component of the profit equation (Revenue – Expenses = Profit) and discuss production expenses/costs and more specifically “What does it cost to produce a calf (in Kansas)?” The Kansas Farm Management Association (KFMA) Enterprise Reports, which may be accessed at https://www.agmanager.info/kfma, are an excellent resource for production cost data in Kansas. This information may be used by cattle producers to benchmark their operations with other comparable enterprises (Spring vs. Fall calving etc.). The total feed and operational costs (total of all non-feed costs) per cow from 2018 to 2022 for all KFMA cow-calf operations is illustrated below.

Figure 1. Total feed and non-feed costs (operational) of Kansas cow-calf producers

This figure demonstrates that both feed and non-feed costs have increased over the last five years and that non-feed costs are often greater than or equal to feed costs. The average cost to produce a calf in 2018 was $1041/cow and was $1,239/cow in 2022. When expressed as a percentage the total cost to produce a calf in Kansas increased 19% from 2018-2022. Further increases in production costs may be expected in 2023 given current economic conditions and the persistence of drought conditions.

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

One of the primary challenges associated with weaning calves is simply getting newly-weaned calves to consistently consume feed. The transition from a milk and grazed forage to grazed forage and supplement, hay and supplement, or a ration containing novel feeds delivered in a bunk isn’t always easy. However, a little preparation and following a simple feeding management strategy can help calves make this necessary transition. Feeding both cows and calves a small amount of the supplement or weaning ration prior to weaning, in the weaning pen or pasture can be used help acclimate calves to both the feeds and the environment. Additionally, feed intake of weaned calves is often low (1.0 to 1.5 % of bodyweight, dry basis) immediately following weaning. Calves also have relatively high nutrient requirements. Thus, the weaning diet must be nutrient dense to meet the nutrient requirements of the calves at the expected intakes previously mentioned. Unfortunately, the dry feeds calves are often most familiar with (typically grass hays) are not necessarily nutrient dense. At the K-State Agriculture Research Center in Hays, a feeding management protocol for weaning calves has been developed that works well for transitioning weaned calves to a total mixed ration. The protocol is summarized in the table below. Essentially, high-quality grass hay and the weaning ration are offered each at 0.5% of the calves’ current bodyweight, dry basis, on the day of weaning. The weaning ration is placed in the bottom of the bunk and the hay is placed on top. The amount the weaning ration is steadily increased, while the amount of hay offered remains constant. In addition, on day 4 the hay is placed on the bottom of the bunk. Over a period of 7-10 days the dry intake of the calves is steadily increased and should reach approximately 2.2-2.5% of the calves bodyweight by 10-14 days following weaning.

Many producers are weaning and will be marketing calves in the coming weeks and months. Margins in the cattle industry are often narrow and maximizing calf revenue is important for cow calf producers every year. Calf revenue from my academic perspective is driven by three 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 three 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 two 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 when they 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 seven weights in February helps producers make an informed data-driven decision for their operations.

Producers also control what information or data they pass along to the new owner. Data has value in today’s world. I compare marketing calves to selling a beautifully restored pickup. If you were selling a classic pickup, you would share with a prospective buyer every bit of information you had, parts invoices, repairs etc. Why should selling a set of calves be any different? Value added programs and certified sales offer potential buyers some degree of assurance that cattle were managed within the guidelines of a specific 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.

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

Justin Waggoner, Ph.D., Beef Systems Specialist

Silage harvest is underway. Cutters and choppers in the fields, trucks racing from the field to the pile or bunker, multiple tractors pushing and packing silage. The speed of silage operations today is impressive, but we should never allow speed to compromise safety. In the infamous words of Dr. Keith Bolsen “Every silage accident could have been prevented.” Now is the time to remind everyone, not just those directly involved with silage harvest on our operations about safety. Below are a few things to consider during this year’s silage harvest.

• Don’t become complacent. Stay aware of the surroundings. There are numerous highly repetitive operations in putting up silage and in agriculture in general. One of the number one factors that leads up to an accident is almost always complacency or a lack of situational awareness. Equipment operators should avoid distractions and should be allowed to take routine breaks to reduce operator fatigue.
• Truck drivers should always slow down when approaching houses and intersections, 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 mail box 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 inform the drivers/operators. Those on the ground in the area should always wear bright colored orange safety vests or clothing and should always make direct eye contact with equipment operators before approaching the area.
• 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 people who may not be familiar with silage activities and the associated risks.
• 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.

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

Justin Waggoner, Ph.D., Beef Systems Specialist

Most cattle producers fully understand the importance of water. After all, providing an adequate supply of clean, fresh, water is the cornerstone of animal husbandry and there are very few things that compare to the feeling of finding thirsty cows grouped around a dry tank on hot day. Water is important, and in situations where the water supply is limited or we are forced to haul water one of the first questions we find ourselves asking is “how much water do those cows need”? The old rule of thumb is that cattle should consume 1-2 gallons of water per 100 lbs of bodyweight. Accurately determining the amount of water cows will voluntarily consume is difficult and is influenced by several factors (ambient temperature), moisture and salt content of the diet, body weight, lactation etc. Water consumption increases linearly as ambient temperature increases above 40° Fahrenheit such that cows require an additional gallon of water for every 10 degree increase in temperature. Additionally, lactation also directly increases the amount of water required by beef cows. The table below summarizes the daily water requirements of beef cows of several different body weights, milk production levels and ambient temperatures (Adapted from Spencer, 2016).

Water is important. The daily water requirements of beef cows in this article are estimates and water consumption varies greatly during the summer months when the temperatures exceed 90° Fahrenheit. Therefore, these recommendations are minimum guidelines. There are a number of excellent resources available on the web, regarding livestock water requirements and water site development.

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

A couple of questions have come up recently regarding early weaning: 1). How early can I wean a calf and 2.) What is the expected benefit of early-weaning? Early weaning is not a term that is well defined, but in general refers to weaning a calf at less than 200 days of age (conventional weaning 180-220 days of age). Calves raised in conventional extensive environments have a functional rumen at approximately 45 days of age and are capable of using dry feeds. However, various research suggests that 120-150 days of age is optimal for implementing an early program. In terms of what can be gained by early weaning. Early weaning is one of the easiest ways to manage cow nutrient demands and reduces the energy requirements of the cow by 25-30%. This effectively means that the nutrients consumed by the cow that were being used to sustain lactation may now be used to improve cow condition. A study designed to evaluate preconditioning duration conducted at K-State documented that cow body condition scores improved as calf age at weaning decreased. The cows on this study remained on native grass pastures following weaning and the observed increase in body condition score in this study occurred over a 60 day period. The results of this study suggest that early weaning calves may improve body condition of cows (up to 0.5 Body condition score) grazing native pastures late in the grazing season.

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

Justin Waggoner, Ph.D., Beef Systems Specialist

It can be challenging to select a mineral program, as there are many different products and mineral formulations currently available. When evaluating mineral supplements the phosphorous concentration may be used as guide to determine if the mineral fits the production stage of the herd and forage base. Phosphorous is one of the most common mineral deficiencies in grazing systems around the world and is one of the primary reasons we provide mineral supplements to grazing beef cattle. The table below illustrates the amount of phosphorous required in a mineral supplement required for cattle at various production stages consuming forages with different phosphorous concentrations. Forage phosphorous concentrations vary and are typically greatest during the spring and lowest in the winter. In Kansas, phosphorous content of native range in the spring is typically between 0.15 and 0.20%. Thus, the maintenance requirements of lactating cow (20 lbs milk/d) could be met by a mineral with at least 8% phosphorous (average of 6 and 10 in the table).

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