In this episode of Diving into Diets, Dr. Brad White and Dr. Phillip Lancaster finish up the essential oils in feed rations series with another article. The experts discuss how essential oils compare to commonly used feed additives like Monensin.
Article Discussed: https://www.sciencedirect.com/science/article/abs/pii/S109002332100054X
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In this episode of Bovine Science, Dr. Phillip Lancaster continues the series with an article that looks into the use of essential oils in feed rations. In part two of the Essential Oils in Rations series, they talk about the different benefits and effects of adding the oils to your feed.
Article Discussed: https://www.mdpi.com/2311-5637/8/6/254
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In this episode of Bovine Science, Dr. Phillip Lancaster brings an article that looked into the use of essential oils in feed rations. The experts go over this paper and the styles of research groups used for the experiment.
Article Discussed: https://www.sciencedirect.com/science/article/abs/pii/S0377840124000841
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In this episode of Bovine Science, Dr. Phillip Lancaster brings an article that looked into the use of essential oils in feed rations. The experts go over this paper and the styles of research groups used for the experiment.
https://www.sciencedirect.com/science/article/abs/pii/S0377840124000841
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Welcome to BCI Cattle Chat! In this week’s episode of Cattle Chat, the crew discuss the changing methods of parasite control. They continue the show by reviewing a paper discussed in a recent Bovine Science episode regarding back fat in bulls. Finally, the team discusses grazing cover crops and the effects on the soil. Thanks for listening and enjoy the episode!
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Compared with carbohydrate and protein metabolism, mineral metabolism in cattle is much less understood. The lack of knowledge about the mineral metabolism has led to an idea among cattlemen that there is something special about certain minerals. Based on what we do know about mineral absorption, the key is to use mineral forms with high absorption. Generally, chloride and sulfate forms (e.g. copper chloride or copper sulfate) have greater absorption than oxide forms (e.g. copper oxide), although this is not always the case (e.g. magnesium oxide ~ magnesium chloride).
Another major issue with mineral absorption is antagonists. Antagonists bind the mineral in the rumen making it unavailable for absorption in the intestine. A common example of antagonism is high levels of sulfur and molybdenum bind with copper creating thiomolybdates rendering copper unavailable for absorption.
Mineral content of feeds can be highly variable affected by the plant species, mineral content of the soil, and mineral availability in the soil where the plants were grown. In many cases, cattlemen have little information on the mineral content of the forage and feed because testing is expensive and rarely performed.
In this uncertainty, the development of organic trace minerals have gained interest as they generally have greater absorption than their inorganic counterparts. In forages and feeds, the minerals are generally in an organic form and thus organic minerals are more similar to the natural minerals in feeds consumed by cattle. However, in feeds, the mineral element is released from its organic form during digestion allowing for absorption.
Organic forms of minerals have generally been reported to be beneficial during times of stress, but results have been inconsistent. A recent meta-analysis of the published studies summarized the results comparing organic and inorganic trace mineral supplementation to feedlot receiving cattle. Overall, organic trace mineral supplementation improved average daily gain 0.13 lb/day but there were some caveats (Figure 1). Average daily gain was improved by organic trace mineral supplementation in cattle classified as low risk (increase in ADG = 0.15 lb/day) for bovine respiratory disease, but not in cattle classified as high risk. In studies with a receiving period longer than 30 days, ADG was increased 0.13 lb/day by organic trace mineral supplementation, but not in studies with a receiving period less than 30 days. Average daily gain was increased 0.13 lb/day when antibiotics (monensin and tylosin) were not used in the feed, but was ADG was not increased when antibiotics were used in the feed.
In regard to bovine respiratory disease morbidity, organic trace mineral supplementation had no effect overall. The effect of organic trace mineral supplementation on morbidity was not affected by BRD risk classification, length of the receiving period, or use of in-feed antibiotics.
In conclusion, supplementation of organic trace minerals can be beneficial in some situations, particularly when antagonisms are impacting absorption of inorganic trace minerals. However, using organic trace minerals in place of inorganic trace minerals will not always result in improved animal performance and health outcomes.
In this episode of Bovine Science, we delve into the intricacies of sorghum silage processing and its impact on beef heifer nutrition. Our discussion centers around the recent study published in the Journal of Animal Science titled “Evaluation of kernel processing and processor type in whole-plant sorghum silage: effects on nutrient digestibility and animal performance in backgrounding beef heifers” (https://doi.org/10.1093/jas/skae369).
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By Phillip Lancaster
In the last decade corn ethanol co-products have replaced a large portion of corn in diets of growing and finishing cattle due to availability and price. However, the price of corn has decreased considerably in the last year making it a cost-effective feedstuff in cattle diets again. A recent study evaluated replacing modified distillers grains with solubles with dry rolled corn in high roughage growing diets. Additionally, the study compared brome hay: sorghum silage with baled corn stalks as the forage source in the diet.
The study used 120 individually-fed steers weighing 620 lb at the start of the study. The steers were fed for 84 days and growth, feed intake and feed efficiency were measured. The diets consisted of 56% forage, 40% a combination of distillers grains and dry rolled corn, and 4% supplement. The main part of the study was to evaluate replacement of modified wet distillers grains with dry rolled corn. There were 4 diets with modified distllers grains at 40, 32, 24, and 16% of the diet dry matter. Dry rolled corn was then included at 0, 8, 16, and 24% of the diet dry matter. As distillers grains decreased in the diet and dry rolled corn increased, there was a linear decrease in gain and feed efficiency such that steers on all diets at the same amount of feed but gained differently (Figure 1).
A probable reason for the decreased gain of steers fed more dry rolled corn could be the decrease in protein in the diet. The protein was 17, 15, 13, and 12% for diets with 40, 32, 24, and 16% distillers grains. In the diets with 24 and 16% distillers grains, urea was added to maintain protein levels at 12%. All diets were evaluated using a nutrition model and results indicated that all diets met requirements for metabolizable protein; however, true protein from distillers grains and microbial protein synthesis from urea may not have been equivalent.
The second part of the study was to evaluate brome hay: sorghum silage versus corn stalks as the forage source in the diet. The brome hay: sorghum silage had crude protein of 7.8%, neutral detergent fiber of 67% and digestibility of 54% compared to 4.0%, 77%, and 49% for the corn stalks indicating that the corn stalks were of lesser nutritional value. The corn stalks were included at 56% of the diet dry matter; the same as the brome hay: sorghum silage such that diets with corn stalks likely had lesser net energy for gain values. Steers fed corn stalks gain 1.76 lb/day compared to 2.89 lb/day for steers fed brome hay: sorghum silage. Interestingly, feed efficiency was the same between forage sources indicating that the lesser gain of steers fed corn stalks was due to lesser feed intake, and not necessarily lesser digestibility of the diet.
In conclusion, when dry rolled corn replaces large amounts of modified distillers grains in forage-based growing diets, a true protein source like soybean meal may need to be added to the diet. Replacing brome hay:sorghum silage with corn stalks may decrease feed intake and growth in backgrounding diets.
Bob Larson, DVM, PhD
Reproductive physiologist and Epidemiologist
Beef Cattle Institute
Kansas State University
RLarson@vet.k-state.edu
Cattlemen throughout history have known that some plants can be toxic to their animals. Some poisonous plants are only present in a few small areas of the U.S. while others are found over a wide geographic area. Some of these plants are poisonous during all phases of growth, while others are only poisonous (or more dangerous) during certain stages of growth or at certain times of the year.
Plants that cause damage to the heart or lungs will generally cause a very rapid death if a large enough dose is eaten – but if the amount consumed is less than a lethal dose, cattle may appear weak and depressed. Plants that are toxic to the liver or kidney seldom cause a rapid death, but instead a slow decline in health and body condition. Consuming plants that cause damage to the liver can result in the buildup of toxins that would normally be removed by a healthy liver. These toxins can cause the skin to become very sensitive to sunburn and can cause other signs of liver failure such as weight loss and poor performance. Some plants are toxic to the kidney – particularly plants such as oak trees that accumulate tannins. Cattle with kidney damage may show signs of reduced appetite, rapid weight loss, and increased water intake.
Some plants are toxic to the nervous system such as some types of ryegrass, locoweeds, and water hemlock. Cattle that eat these plants may suffer from rapid death or longer-term weight loss and nervous system signs depending on the specific plant and the amount consumed. Signs of nervous system problems include staggering, apparent blindness, exaggerated movements, and hyper-excitability.
Abortion or the development of birth defects can occur when pregnant cattle consume certain toxic plants. Abortions caused by toxic plants are often difficult to diagnose, and the birth defects caused by some toxic plants are the same or similar to defects caused by genetic problems or viral infection. Loco weeds, tobacco, lupine, and poison hemlock are known to cause birth defects in calves in certain situations when pregnant cows consume these plants.
In order to diagnose suspected plant poisonings you should work with your veterinarian and a veterinary diagnostic laboratory. Your veterinarian can help you to develop an accurate history and time-line for the problem. To identify the cause of losses due to poisonous plants, the pasture or pen should be inspected, both alive and dead animals should be examined, and diagnostic samples of plants, blood, and tissues should be properly collected and then evaluated by trained diagnostic laboratory personnel. The presence of toxic plants in pastures or hays is not proof that cattle have been harmed by the plants because many time cattle will refuse to eat them. However, finding evidence of consumption of potentially toxic plants by animals, either by observing evidence of grazing of suspected plants or by finding parts of these plants in the digestive tract of a dead animal is highly suggestive of poisonings.
Because removing all toxic plants from a range or pasture is not likely to be practical or successful, good grazing management using stocking density, fencing, water development and salt/supplement placement to maintain good pasture health will
minimize the incentive for cattle to graze toxic plants. If it appears that a toxic plant problem is occurring, cattle should be removed from the suspected pasture immediately and a veterinarian should be contacted. It is important to work with veterinarians, Extension agents, natural resource conservation service specialists, and range specialists who can all help develop a plan to keep pastures healthy and minimize the risk of toxic plant poisonings.
In this episode our hosts discuss the affects of pregnancy on digestion in beef cattle. They look at passage rate and extent of digestibility. Dr. Lancaster brings and article out of Brazil that studies these aspects.
Article discussed: Pregnancy affects maternal performance, feed intake, and digestion kinetics parameters in beef heifers
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Welcome to BCI Cattle Chat! In this week’s episode of Cattle Chat, the team is joined by special guest Dr. Justin Waggoner, KSU Beef Extension Specialist, to dig into the big question: When input costs rise, where can you cut without hurting your herd or your bottom line? The experts will also tackle feeding mineral after turnout for the summer. Dr. Waggoner will wrap up the episode by sharing a little about his research regarding navigating the nutritional limitations of cool season grasses.
3:43 Input Costs
11:42 Pasture Turnout
15:37 Supplementation During Cool Season Grasses:
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Welcome to BCI Cattle Chat! In this episode we are switching things up by answering a myriad of listener questions to get producers ready for the coming season. The experts will discuss prolapses, mastitis, grass tetany, bulls and more. Thanks for tuning in and enjoy the episode!
2:18 Prolapses
7:20 Mastitis
11:53 Magnesium
17:32 Bull Management
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Welcome to BCI Cattle Chat! Dr. Brian Lubbers begins the episode by discussing Hairy Heel Warts in feedlots. He explains what could cause them and how it can be treated. Next, the experts discuss bulls composition and BCS for cows versus bulls. Finally, Merri Beth Day is back to discuss her research on sustainability in the cattle industry. Thanks for tuning in and enjoy the episode!
2:25 Listener Question, Hairy Heel Warts
11:18 Bull Composition
15:58 Sustainability with Merri Beth Day
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Dr. Phillip Lancaster brings us an article out of China that looks at what effects diet has on calves rumination and overall health. The study looks at calves with and without forage inclusion. They discuss the research procedure and how the results could apply to beef calves in the U.S.
Article Discussed: How neonatal diet affects the long-term development of rumination behavior, rumen fermentation and feed digestion in dairy calves fed a high milk level?
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Welcome to BCI Cattle Chat! We are joined this week by Associate Professor Dr. Pedro Fontes sponsored by ESTROTECT. He and Dr. Bob Larson start the episode by discussing common synchronization problems. Dr. Brad White then asks Dr. Fontes about some of his research on sire nutrition and fertility. The experts finish the episode by discussing what causes pregnancy loss in the first trimester. Thanks for tuning in and enjoy the episode!
3:41 Common Synchronization Problems
11:38 Sire Nutrition and Fertility
17:43 Pregnancy Losses in the First Trimester
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Welcome to BCI Cattle Chat! This episode one of our students Liliana Rivas joins to tell us about her research with beef-dairy cross calves. Next, Marshall Stewart is back to tell us about K-State’s new project with Garden City Community College. Dr. Lancaster finishes the episode by answering a listener question concerning a cow feed program. Thanks for tuning in and enjoy the episode!
3:00 Liliana Rivas Research Update
10:05 Marshall Stewart: Garden City Partnership
16:48 Listener Question: Feed Program
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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In this episode Dr. Phillip Lancaster and Dr. Brad White are talking about methane emissions. Dr. Lancaster also brings an article out of Australia which looks at adjusting grazing systems to reduce the methane in the cow-calf sector. Thank you for listening and enjoy the show!
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Fescue toxicosis is a syndrome of cattle consuming endophyte-infected tall fescue. The endophyte provides a hardiness to the plant allowing the plant to grow in stressful conditions such as drought and cold temperatures. However, the endophyte produces ergot alkaloids that are detrimental to cattle performance. Cattle experience hormonal changes in the production of and response to natural serotonin that result in lower heat tolerance and reduced feed intake.
Serotonin is synthesized in the body from the amino acid tryptophan. One therapy being explored is administration of 5-hydroxytryptophan, which is a step in the synthesis of serotonin from tryptophan. In a recent study, researchers at USDA-ARS tested the effect of 5-hydroxytryptophan on the response of steers fed endophyte-infected fescue seed. By providing 5-hydroxytryptophan, the researchers were able to reverse the negative effects of ergot alkaloids on blood serotonin levels and cattle feed intake (Figure 1). The control steers that were not fed endophyte-infected seed or 5-hydroxytryptophan consumed 1.9% of body weight whereas the steers fed endophyte-infected seed without 5-hydroxytryptophan consumed only 1.8% of body weight. However, when steers fed endophyte-infected seed were also given 5-hydroxytryptophan, feed intake was not different from the control steers indicating that 5-hydrxytyptophan reversed the negative effects of endophyte-infected seed on feed intake.
Giving cattle grazing endophyte-infected tall fescue a dose of 5-hydroxytryptophan would likely greatly improve the performance of these cattle. However, 5-hydroxytryptophan is not ready for commercial application yet. In this study, steers were dosed with 5-hydroxytryptophan through a rumen cannula into the abomasum, thus bypassing the rumen microbes and any possible degradation of 5-hydroxytryptophan. Before 5-hydroxytryptophan could be added to feed, a method to protect it from the rumen microbes will need to be developed. However, this molecule shows great potential to improve performance of cattle grazing endophyte-infected tall fescue.
In this episode of Diving into Diets a Bovine Science Podcast Dr. White and Dr. Lancaster look at a research paper about the effects of poor nutrition on late gestation cows. They will dive into what this means for future research as well as their key takeaways.
Article Discussed: Colby A Redifer, Lindsey G Wichman, Shelby L Davies-Jenkins, Abigail R Rathert-Williams, Harvey C Freetly, Allison M Meyer, Late gestational nutrient restriction in primiparous beef females: Performance and metabolic status of lactating dams and pre-weaning calves, Journal of Animal Science, Volume 102, 2024, skae015, https://doi.org/10.1093/jas/skae015
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Welcome to BCI Cattle Chat! This episode begins with Dr. Brian Lubbers explaining compounding medication for meat animals. The show progresses with the experts answering a listener question asking about whether you should remove net wrap from hay bales or if they can go through the tub grinder. The episode concludes by discussing protein tubs and picking the right one for you. Thanks for tuning in and enjoy the episode!
3:24 Compounding Medication
9:50 Listener Question: Leaving the Net Wrap On
18:18 Listener Question: Using Protein Tubs
For more on BCI Cattle Chat, follow us on X at @ksubci, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Welcome to BCI Cattle Chat! This episode begins with Dr. Phillip Lancaster and Dr. Bob Larson discussing whether creep feeding calves is worth it. The show progresses with the experts answering a listener question asking about creating a finishing ration for cattle. Dr. Brad White wraps up the episode by discussing how many vaccines it is acceptable to give your cattle. Thanks for tuning in and enjoy the episode!
3:30 Should I use a creep feeder?
10:45 Listener Question: Starting Cattle on a Finishing Ration
15:40 How many vaccines is too many?
For more on BCI Cattle Chat, follow us on X at @The_BCI, Facebook, and Instagram at @ksubci. Check out our website, ksubci.org. If you have any comments/questions/topic ideas, please send them to bci@ksu.edu. You can also email us to sign up for our weekly news blast! Don’t forget if you enjoy the show, please go give us a rating!
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Can we use rye grain to finish cattle? In this episode of Bovine Science Dr. Lancaster and Dr. White look into a research paper covering this topic. With this research paper titled, “Production and use of dry-rolled hybrid rye grain as a replacement for barley grain on growth performance and carcass quality of feedlot steers ” (Zhang et al.) they discuss the possibility of feeding rye versus feeding barley and it’s effects on the cattle. Thanks for listening and enjoy the show!
Link to Article: Fuquan Zhang, Rachel E Carey, Rebecca S Brattain, Herman Wehrle, Gregory B Penner, Production and use of dry-rolled hybrid rye grain as a replacement for barley grain on growth performance and carcass quality of feedlot steers, Translational Animal Science, Volume 8, 2024, txae059, https://doi.org/10.1093/tas/txae059
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| Phillip Lancaster, MS, PhD Ruminant nutritionist Beef Cattle Institute Kansas State University palancaster@vet.k-state.edu |
Pasture management is a key component to cow-calf production systems by affecting the carrying capacity of grasslands but also the ability of forage to meet the nutritional requirements of cattle. A lot of focus has been on management intensive grazing (e.g., rotational grazing, adaptive multi-paddock grazing, etc.) and its ability to maintain or increase the ecosystem function and productivity of rangelands. However, another important component of rangelands is fire.
A recent study evaluated the effects of patch-burning on forage nutritive value, animal grazing distribution, and animal performance. Patch-burning is a practice where only a section of the pasture is burned every 3-5 years rather than burning the entire pasture at once. This creates an array in grazing pressure across the pasture, adds heterogeneity to the landscape for different wildlife species, helps control undesirable plants, and leaves plant residue to increase organic carbon back into the soil. In the study, continuous grazing management was used with patch burning treatment and was compared with continuous and rotational grazing management systems without fire in mixed grass rangeland. Each of the 3 treatments had 4 pastures and Angus cow-calf pairs were used to graze the pastures over a 4-year period. The rotational grazing system was a seasonal rest-rotation within a twice-over rotational system.
In the year of burning, patch-burned sites had improved crude protein, acid detergent fiber, and neutral detergent fiber digestibility of forage than continuous and rotational grazing systems without fire. Patch-burned sites that were burned 1 to 3 years prior also had improved forage nutritive values compared with continuous and rotational grazing systems without fire. Only the unburned site in the patch-burned treatment had lower forage nutritive value than the continuous and rotational grazing systems without fire. The rotational grazing system had improved forage nutritive value than the continuous grazing system.
In the patch-burned treatment, cattle spent more time in the most recently burned section of the pasture most likely due to the increase forage nutritive value. Additionally, the most recently burned section had the greatest proportion of forage samples that met or exceeded the nutrient requirements of cows (Figure 1). This resulted in cows in the patch-burn treatment gaining > 0.4 lb/d compared with < 0.2 lb/d for cows in the continuous and rotational grazing treatments without fire. Thus, the need for protein supplementation of cow-calf pairs may be decreased when patch-burn grazing is used.
In conclusion, patch-burning can be used to improve forage nutritive value for grazing cattle in continuous grazing systems compared with rotational grazing systems. Patch-burning can also be used to concentrate grazing on different sections of the rangeland over time because cattle will preferentially increase time spent in the most recently burned section of the rangeland. Additionally, patch-burning is a good management practice to blend cattle production with wildlife conservation goals.
Figure 1. The proportion of forage samples meeting or exceeding nutrient requirements for protein and energy of 1250-lb cow producing 18 lb/d at peak milk. Adapted from Wanchuk et al., (2024; https://doi.org/10.1016/j.agee.2024.109004)
Every summer ranchers cut and bale hay for the winter and don’t think much about it. But the nutritive value of hay is highly variable and not always represented by the visual appraisal of the hay.
The nutritive value of hay is primarily a function of protein concentration and digestibility. The protein in hay is primarily digested by the bacteria in the rumen which are then digested by the animal in the small intestine; thus, providing the animal the protein that it requires. As grasses grow the protein concentration decreases; however, this change in protein concentration is not consistent among species of grasses or for the same species across years.
Digestibility is a function of the fiber concentration in the grass. There are several types of fiber, but neutral detergent fiber (NDF) and acid detergent fiber (ADF) are two types of fiber related to digestibility. NDF is the total amount of fiber in the plant and ADF is the amount of poorly digested fiber in the plant. As the total amount of fiber (NDF) increases the digestibility of the grass decreases, and as the amount of ADF increases the digestibility of the grass decreases. From the NDF and ADF concentrations in the hay, we can calculate an estimated digestibility (TDN). As grass grow, the NDF and ADF concentration increases and similar to the protein concentration, this change is not consistent among species or across years.
Visual appraisal of hay can be deceiving. Figure 1 is a picture of some bromegrass hay that has a high number of leaves and relatively few stems. Although, stems are present indicating that the plant had reached reproductive stage prior to cutting and baling. The reproductive stage, when seed heads are visible, is one of the later stages of plant growth indicating a lesser quality hay will be produced. However, bromegrass hay is usually a relatively high-quality grass hay.
Figure 2 is the nutritive analysis of the hay in Figure 1. Even with a high number of leaves the protein concentration is quite low at 6.39 %. Feed tables list the protein concentration of bromegrass hay at >8%, which will meet the protein requirements of mid-gestation dry cows; 6% protein will not. Late gestation and lactating cows will need a protein supplement to meet requirements as their protein requirements are 9 to 10%.
The NDF concentration of the hay in Figure 1 was 63% and the ADF was 41%. This calculated to an estimated TDN of 51%, which is just enough to meet energy requirements of mid-gestation dry cows. And with the marginal protein concentration in the hay, the cows will need a protein supplement to be able to digest the hay up to the potential calculated TDN of 51%.
Visual appraisal of hay is not always adequate to assess the nutritional value of the hay. Even home-grown hay can have nutritive value very different than what is expected or what forage analyses from previous years indicates. A basic forage test that will provide protein, NDF, ADF, and TDN concentrations costs $20 to $40 per sample. One sample from each cutting and each field is adequate, but the sample needs to comprise of hay from multiple bales. The best way to sample hay for forage analysis is to use a hay probe on a cordless drill and collect a core from 10% of the bales. The $100 to $200 spent on forage analysis is worth the cost of 1 open cow from feeding hay that results in thin cows at calving.
