Farmers and ranchers in the Intermountain West commonly use supplemental nutrients to keep cattle productive, especially when grazing rangeland in the fall and winter. Grazing cattle struggle to consume enough nutrients (energy, protein, vitamins, and minerals) from western rangelands to fulfill their nutrient requirements and maintain acceptable production levels.
During these times, targeted supplemental feeding — specifically protein supplementation — is necessary. As daily foraging reduces crude protein intake in colder months, protein supplementation is vital to promote efficient digestion to maintain body composition while boosting fetal growth and lactation.
Supplementing cattle feed with IFA’s Crystalyx protein tub line or new Rumax BoviBox protein blocks supply the necessary balance of crude protein, fat, live active probiotics, and amino acid complex to combat the effects of fall and winter conditions on grazing cattle.
Four Reasons Why Protein Supplements Are Vital for Grazing Cattle
1. Grazing Cattle Require Ruminant Nutrition to Balance Digestive Microorganisms for Energy
A fundamental understanding of ruminant nutrition aids in making supplement choices. Cattle are ruminants and they are different from pigs, horses, and humans. Cattle have a rumen in which ingested feedstuff is digested and fermented before it reaches the stomach (called the abomasum in the cow). The rumen provides an optimal environment for the existence and growth of microorganisms.
Rumen microorganisms digest feeds and during that process, energy and other nutrients become available to support microbial growth. At the same time, a symbiotic relationship exists between the microorganism’s and the host in which valuable nutrients are made available to the host. Rumen microorganisms release volatile fatty acids, which the ruminant uses as its major source of energy. Also, microorganisms (cells) eventually flow out of the rumen and are digested in the small intestine of the host. These cells contain approximately 50% protein and contribute to the animal’s overall protein supply.
2. Cold Weather Conditions Reduce Microbial Digestion Efficiency in Grazing Cattle
The efficiency of microbial digestion is often reduced in cattle grazing fall and winter forages. Reduced digestion efficiency limits nutrient flow and puts cattle at risk of losing body condition. The rumen microorganisms must have protein (nitrogen) for growth and production. Fall and winter forages are often low in protein content and the crude protein of forage can range for 4.0% to 7.0%. Supplemental protein can maximize rumen microbial growth and function. Research proves that meeting the microorganism’s requirement for protein (nitrogen) yields positive effects on forage intake, digestion, and rate of nutrient passage and improved usage of low quality feeds.
3. Dormant Forages Reduce Daily Grazing Intake
Daily energy intake can be a limiting factor for cow performance while grazing fall/winter forage or dormant forages. As forages advance in stages of maturity, there is an inadequate supply of crude protein, which effectively limits daily intake and available energy to the animal. Intake declines rapidly as forage crude protein falls below 7%, and can be attributed to a deficiency of nitrogen (protein) in the rumen. If the forage diet contains less than about 7% crude protein, feeding a protein supplement generally improves daily intake and energy and protein status of cattle.
4. Nutrient Demands Increase During Lactation, Fetal Growth and Calf Growth
During lactation, mid to last trimesters of gestation, and growth of younger cattle, cattle experience their highest nutrient demands. During drought conditions or when grazing fall/winter forages, protein supplementation allows the animal to maintain production, protect fetal growth, and limit body condition loss. As a rule of thumb during this time period, feed 0.3 to 0.6 pounds of crude protein per day. Offer protein supplements to cows daily, three days a week, or as infrequently as once per week to maintain adequate performance.
Types of Protein Supplements for Grazing Cattle
Supplemental protein is available in many forms including cakes, cubes, salt meal mixes, blocks, tubs, or high protein forages. Crude protein comes from natural protein sources or non-protein nitrogen sources (i.e., urea or biuret), but most supplements blend the two. Non-protein nitrogen sources, such as urea, are a less expensive form of protein and are utilized in most protein supplements. But when feeding or grazing low quality forages, the percent non-protein nitrogen should be 14.5% or less.
Determine Supplement Portions — And Cost — Using Body Condition Scores (BCS)
Feed costs are a major expense for any cow/calf operation. What can you afford? Nutritional planning measures cost with Body Condition Scores (BCS). If cattle BCS is below 5.0, optimal protein supplementation helps to prevent BCS loss during lactation. If BCS are 4.0 or less, wean calves to lower their nutrient requirement (Figure 1) and start rebuilding cattle BCS.
When and How to Calculate Body Condition Scores (BCS) of Grazing Cattle?
Body condition scores (BCS) describe the relative fatness of a cow through the use of a nine-point scale. Body condition scoring is an effective management tool to evaluate the nutritional status of the herd. For a spring calving herd, the key times to BCS your gestating females are late summer (early wean if needed) or fall weaning. This is the most economical time to put condition on thin cows is after weaning.
In Figure 1, the cow’s highest energy requirement is at peak milk production, about 60 days after calving which also coincides with the breeding season. She has calved, is producing milk, is recovering from calving, and getting ready for breeding. To help prepare your mature cows for this, have them in a body condition score (BCS) of at least 5.0. The heifer is still growing, and it is recommended that she be in a BCS of 6.0 at calving. Separating heifers from the mature cows should be done at least three weeks prior to calving. First-calf heifers decrease their daily dry matter intakes by 17 percent in the three weeks prior to calving. Feeding an energy and protein dense diet to heifers is necessary to compensate for this reduced intake at calving.
Low body condition scores influence herd productivity. As cattle body condition score decreases at calving, the interval from calving to the first estrus is reduced (Table 1). Thin (BCS 4 or less) cows are slower to rebreed after calving compared to cows in moderate body condition.
Customize Nutritional Programs to Avoid Losses in Cattle Production
Supplemental protein programs help avoid costly losses in BCS. They can either increase BCS, particularly during the cow’s lowest nutrient requirements, or maintain and minimize BCS losses during times of higher nutrient requirements.
Intermountain Farmers Association cattle feed experts help clients build herd nutritional programs to avoid costly losses in animal production. Our protein products aid producers in meeting their production goals.
This year, in addition to our Crystalyx protein tub line, we have added a new 100-pound protein block that is highly fortified. This new Rumax BoviBox block contains 30% crude protein, 4.5% fat and is the only product that contains a live active probiotic. It is formulated with a complete vitamin and mineral package that contains the recommended level of organic trace minerals (Zn, Cu, Mn, and Co Amino Acid Complex). These Amino Acid Complex trace minerals help offset many of the western mineral antagonists that bind and render dietary trace minerals unavailable to the animal. Rumensin can be added to the block to help with feed efficiency and Coccidiosis control.
Please contact your local IFA branch or sales representative for all of your herd nutritional programs. We can help make a difference.
Written by Jim Lamb, Ph.D., PAS, Nutritionist IFA and originally published in the IFA Cooperator magazine (vol. 90, no. 4) Winter 2024.
Jim Lamb is a certified Professional Animal Scientist with a strong drive for learning and love of agriculture. Raised on his family’s ranch on the Arizona strip, Jim has a long resume in the cattle industry. He obtained his bachelor’s degree in range science from Utah State University followed by a master’s degree in animal science from New Mexico University. After graduating with his PhD in ruminant nutrition from the University of Nebraska-Lincoln and passing the Professional Animal Science Exam, Jim worked for several companies as an animal nutritionist and taught at Brigham Young University-Idaho. Jim remains active on his family’s ranch while aiding intermountain ranchers as an IFA Nutritionist.