Welcome to BCI Cattle Chat! The hosts begin the episode by answering a listener’s question about the causes and prevention methods associated with dummy calves. Dr. Brian Lubbers progresses the show with a conversation about health label claims on food products. The experts wrap up this edition of Cattle Chat by updating the listenership on the summer research projects they have been working on with BCI students. Thanks for tuning in and enjoy the episode!Â
2:00 Listener Question: Dummy Calves
10:16 Yogurt Health Claims: A discussion on the implications of health label claims on animal-derived food products
14:45 Summer Research Update: AIP, cowherd simulators and data
For more on BCI Cattle Chat, follow us on Twitter 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!
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Warm, stagnant, surface water, often with a mechanism of phosphorus and nitrogen loading. Algae may appear as a scum on the surface that resembles paint. These blooms are buoyant and often concentrate on the downwind side of ponds.Â
Mechanism
Hepatotoxic algal toxins disrupt the microstructure inside hepatocytes resulting in acute, severe hepatocellular necrosis.
Neurotoxic algal toxins cause a severe neuromuscular blockage.
Signs
The most common clinical signs observed is acute death. The neurotoxins produced by these algae are some of the most potent biotoxins known and can result in death in minutes. The hepatotoxic varieties are the most commonly-encountered in most places where cattle production occurs. Death from exposure often occurs in 24 hours. Clinical signs, if observed, are typically non-specific. Animals may only appear depressed which progresses to tachypnea with signs of abdominal pain and death.
Treatment
Due to the severe nature of the exposure, effective treatments have not been identified. Once animals show clinical signs, a lethal dose has likely been consumed.
Diagnosis
Identification of algae and toxins in water sources, histopathology of the liver.
Fritz, S. A., Charnas, S., & Ensley, S. (2024). Blue Green Algae. Veterinary Clinics of North America: EquinePractice, 40(1), 121-132. doi:https://doi.org/10.1016/j.cveq.2023.10.006
Two 10-year-old cull cows were placed into a small pasture to put some weight on before going to town. Two weeks later, they are both dead with no clinical signs of disease. Dr. Scott Fritz and Dr. Brad White get to the bottom of this case in this edition of Tox Talk: a Bovine Science with BCI podcast. Thanks for tuning in and enjoy the show!
The toxicology website and Bovine Sciences with BCI podcasts have been sponsored in part through a veterinary services grant that Dr. Scott Fritz, Dr. Steve Ensley and Dr. Bob Larson have received to share more toxicology information and examples for people to understand what to submit and how to submit. Another part of that grant has been working with people and producer in the field.
Welcome to BCI Cattle Chat! To kick off the show, Dr. Dustin Pendell and the other hosts examine a recent report from the Kansas Farm Management Association titled 2023 Executive Summary, which contains data about net farm income, government payments and insurance in Kansas. To continue the show, Dr. Phillip Lancaster explains how to properly body condition score cattle. Lancaster concludes this edition of Cattle Chat by discussing with Dr. Brad White the beef production challenges associated with excess rain. Thanks for tuning in and enjoy the episode!
2:27 KFMA 2023 Executive Summary: Net farm income, government payments, net worths, averages
13:55 Body Condition Scoring: A How To
18:45 Excess Rain: effects on pasture, cow performance, foot rot, water logged grasses
For more on BCI Cattle Chat, follow us on Twitter 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!
Bob Larson, DVM, PhD Reproductive physiologist and Epidemiologist Beef Cattle Institute Kansas State University RLarson@vet.k-state.edu
Beef production has become more efficient in the 30-plus years that I have been involved in the industry. This achievement is due in large part due to the genetic selection efforts of seedstock suppliers. I am surprised at times when this achievement is overlooked and sometimes even derided by some beef producers and agriculture detractors.
As in all discussions, it is important to clarify the meaning of key words. Efficiency in beef production is defined as the value of all inputs or amount of inputs of particular value divided by the quantity or value of output. Some examples include, dollar value of all inputs divided by pounds of weight sold or amount of specific inputs such as acres of land, gallons of petroleum products, or number of breeding females divided by the number or value of pounds sold. Using modern breeding, health, and growth management, U.S. beef producers produce much more beef per acre, per gallon of petroleum product, and per bred female than was conceivable a generation ago.
Some of the areas within beef production that I think have not reached their potential efficiency include: number of calves born per exposed female, percentage of calves that survive to market, growth efficiency (pounds of weight gain per calorie consumed), water use efficiency, number or pounds of calves per acre of land, and percentage of USDA Choice and higher grading carcasses per inputs such as acre of land or calorie of feed. Improving efficiency in these areas involve all aspects of cattle and beef production including genetic selection, grass and range management, reproductive management, health management and disease prevention, and nutritional management.
One important caution when designing a management system to improve efficiency using a single measure is the risk of decreasing efficiency as determined by other measures. For example, a single-minded effort to increase pounds per calf weaned may decrease calves weaned per acre and calves weaned per cow exposed – thereby decreasing efficiency measures such as pounds/value sold per acre or pounds/value sold per exposed cow. Sometimes efforts to improve cost efficiency when measured as dollars of expense per cow exposed will backfire if number of calves weaned per cow exposed or weight/value of calves weaned decreases, resulting in higher expenses per dollar of income.
It is important when determining how you want to improve efficiency to recognize what resources on your farm are most valuable and need to be conserved. If land is your most valuable resource (as determined by being the input accounting for the highest percentage of cost), you must not lose sight of value of outputs per acre of land. If cows are your most valuable resource, you most emphasize value of output per cow exposed. By focusing your management plan on improving the efficient use of the most important two or three inputs on your particular operation, improving efficiency has the most opportunity to improve profitability of your cattle business. Over time, the values of some inputs are likely to increase or decrease in relative importance, meaning that you must occasionally evaluate which inputs are currently the most valuable and readjust your management to emphasize their efficient use.
Many people will quickly recognize that increased efficiency does not equal increased profits. This is due to the fact that the value of both inputs and outputs are largely driven by the supply and demand of competing products – independent of beef production costs. In addition, the value of key inputs such as land has grown even faster than the growth in efficiency of land use. What is often incorrectly implied is that since increased efficiency does not automatically lead to increased profits – that decreased efficiency would automatically lead to increased profits. However, it is difficult to imagine a successful long-term business plan based on production of less beef per valuable resource such as acre of land, gallon of gasoline, or bushel of corn or ton of hay. Profitability for beef production relies both on increasing efficiency and strengthening ones marketing position in relation to competitors.
The beef industry should be proud of the fact that we have learned to use the resources that this country greatly values (i.e. land, labor, petroleum, and feed) more efficiently. There are still opportunities to continue this tradition of stewardship and I look forward to seeing the improvements that we will achieve during the rest of my career in the beef industry.
In the last edition of Herd Health: a Bovine Science with BCI podcast, Dr. Bob Larson and Dr. Brad White discussed AI (artificial intelligence). During this episode, the experts talk about a different kind of technology with the same abbreviation: artificial insemination. Tune in to learn more about a paper regarding different protocols and what to do after a mistake during the synchronization process. Thanks for listening and enjoy the show!
Welcome to BCI Cattle Chat! This episode begins with Dr. Phillip Lancaster and Dr. Bob Larson discussing different strategies for feeding cattle during extreme heat. The show progresses with a conversation concerning risk management methods that producers should contemplate now for shipping calves in the fall. Larson continues the episode by examining three facial diseases: lumpy jaw, wooden tongue and cancer eye. To wrap up this edition of Cattle Chat, the experts share different criteria for culling cows during this period of record high prices. Thanks for tuning in and enjoy the episode!
2:18 Heat Feeding: Adjusting rations and feeding times, water consumption, heat from fermentation
For more on BCI Cattle Chat, follow us on Twitter 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!
What do all classes of cattle have in common? One answer is that they all share the need for the right amount of carbohydrates/energy in their diets to maintain proper health and nutrition. Dr. Phillip Lancaster and Dr. Brad White explain all things energy during this episode of Diving into Diets: a Bovine Science with BCI podcast. The experts talk about topics like energy’s role within a ration and how to calculate net energy. Thanks for listening and enjoy the show!
Welcome to BCI Cattle Chat! Dr. Brad White opens up this episode by asking the other hosts questions regarding fly control, grazing and pink eye. The experts continue the show by discussing a listener’s question about calves trying to nurse first-calf heifers instead of their dams. This edition of Cattle Chat winds down with Dr. Brian Lubbers and Dr. Bob Larson explaining how antibiotics work and their role within beef cattle production. Thanks for tuning in and enjoy the episode!
9:00 Listener Question: Calves not nursing where they are supposed to
13:12 Antibiotics: How they work, the different classes and considerations before use
For more on BCI Cattle Chat, follow us on Twitter 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!
40% death loss occurs in only the young calves belonging to first-calf heifers within a large herd. Dr. Scott Fritz and Dr. Brad White analyze this abnormal case and discuss the necropsy process leading to diagnosis in this edition of Tox Talk: a Bovine Science with BCI podcast. Thanks for tuning in and enjoy the show!
The toxicology website and Bovine Sciences with BCI podcasts have been sponsored in part through a veterinary services grant that Dr. Scott Fritz, Dr. Steve Ensley and Dr. Bob Larson have received to share more toxicology information and examples for people to understand what to submit and how to submit. Another part of that grant has been working with people and producer in the field.
Welcome to BCI Cattle Chat! Dr. Fred Gingrich, DVM and executive director of the American Association of Bovine Practitioners, sits down with the hosts to provide an update on the Highly Pathogenic Avian Influenza outbreak — a virus recently transmitted to dairy cattle called H1:N1. The experts and Dr. Gingrich progress this episode by sharing their thoughts on technologies in veterinary medicine that may assist beef cattle production in the future. To wrap up this edition of Cattle Chat, Dr. Brad White asks the other hosts and guest some rapid-fire questions concerning hay storage, a beef cattle sedative and other topics. Thanks for tuning in and enjoy the episode!
3:20 Highly Pathogenic Avian Influenza: A broad overview, symptoms, communication, and what’s next
9:55 Future Veterinary Technologies: the role of veterinarians, genetic modification, feeding cattle and data
15:53 Rapid Fire Questions: Hiring professionals, Xylazine, storing round bales and interacting with younger generations
For more on BCI Cattle Chat, follow us on Twitter 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!
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Calves are usually affected due to dams being deficient in vitamin E and/or selenium during gestation. Selenium is naturally found in grains and forage. However, certain areas of the country such as the northeast, eastern seaboard, and northwest are known to have deficient selenium levels in the soil. Vitamin E is normally found in high-quality hay, silage, and green forage. Supplements containing vitamin E can also be administered. Selenium is legally regulated in feed supplements due to its toxic potential.
Mechanism
Vitamin E and selenium act as antioxidants and protect cells from damage caused by free radicals. Without this protection, heavily oxygen-dependent cells like cardiac and muscle cells are injured or die.
Signs
Animals with primarily skeletal muscle damage can show an altered gait, muscle weakness, difficulty rising, and pain on palpation.
Animals with primarily cardiac damage can show respiratory stress, difficulty breathing, and a buildup of fluid in the abdomen due to heart failure.
Treatment
Supportive care is necessary to make sure the animal is stable. Once stable, supplementation of vitamin E/selenium should be administered to the affected animal. Injectable selenium and vitamin E supplements are available for short term use. The diet should be evaluated to make sure appropriate amounts of vitamin E and selenium are present to avoid further deficient animals.
Diagnosis
Vitamin E ïƒ serum (red top tube) or fresh/frozen liver
Selenium ïƒ whole blood (purple top tube) or fresh/frozen liver; feed samples can also be analyzed
Phillip Lancaster, MS, PhD Ruminant nutritionist Beef Cattle Institute Kansas State University palancaster@vet.k-state.eduÂ
Hay is one of the most expensive feedstuffs available to cattle producers. Hay harvesting equipment, spoilage and wastage, and delivering hay to cattle in drylot add tremendous cost to hay. On a per pound of nutrient basis, hay is generally more expensive than bulk commodities such as corn, soybean hulls, and distillers grains. Reducing this cost can improve the bottom line of the cow-calf operation.
One of the ways to reduce the cost of hay is to decrease the amount of spoilage and wastage. Spoilage occurs when hay absorbs moisture during storage then cattle avoid consuming that part of the bale thereby wasting it. Thus, anything we can do to reduce the amount of moisture absorbed by the bale during storage will reduce spoilage and wastage.
One of the most important storage considerations is to raise bales off the ground so that moisture from the ground is not absorbed into the bale. Bales sitting on the ground can result in 5 to 20% spoilage compared to 3 to 15% of bales eleveated off the ground. Raising bales off the ground can be done in a variety of ways – laying down large rock (3 or 4 inch limestone rock), old tires or old pallets, etc. Moisture wicking from the ground is more important in smaller diameter round bales. In smaller bales, a greater percentage of the bale mass is in the outer layer such that spoiled hay is a greater percentage of the bale. Also, the thickness of the outer layer impacts spoilage as a thicker outer layer constitutes a greater percentage of the bale mass. These factors are compounded where smaller bales with thicker outer layer have the greatest spoilage.
A second consideration is to store bales in a designated hay lot where vegetation can be controlled compared to along the edge of the hay field. Along the edge of the field, vegetation usually gets tall and thick, and the bales are many times under the overhang of trees. This vegetation holds moisture around the bale and increases spoilage. Storing bales in an open hay lot removes trees and allows other vegetation to be controlled so that bales can dry out after a rain or snow event. Aligning the bales in rows running north and south allows the sun to shine down between the rows and leaving a few feet between rows allows for better control of vegetation so that sunshine better dries out the bale after a rain or snow event.
The best way to reduce moisture absorption by bales is by storing them in an enclosed barn resulting in less than 2% spoilage even when stored for a very long time. However, construction of a hay barn is expensive adding to the cost of hay as a feedstuff for cattle. Less costly methods of covering bales can be used. Constructing a hay barn with only a roof and open wall generally results in similar spoilage (2-5%) as a enclosed barn. Also, stacking bales in a pyramid shape and covering them with a tarp results in 5 to 10% spoilage when on the ground and 2 to 4% spoilage when elevated off the ground.
As the value of hay increases so does the cost of spoilage. As an example, if hay is $100 per ton, then 10 % spoilage costs $10 per ton so the hay that cows were fed actually cost $110 per ton. In January 2024, bluestem grass hay was ~$180 per ton and with 10% spoilage was $198 per ton. Thus, to feed a 1300-lb cow for 120 days, hay cost alone would be $32 more with spoilage.
Hay spoilage with different storage methods at different time frames and estimated cost at hay price of $150 per ton.
Method
Store for 9 months
Store for 15 months
Cost per Ton
Uncovered
Ground
5 to 20%
15 to 50%
$7.50 to $30.00
Elevated
3 to 15%
12 to 35%
$4.50 to $22.50
Covered
Ground
5 to 10%
10 to 15%
$7.50 to $15.00
Elevated
2 to 4%
5 to 10%
$3.00 to $6.00
Under roof
2 to 5%
3 to 10%
$3.00 to $7.50
Enclosed barn
< 2%
2 to 5%
<$3.00
Adapted from Beef Cattle Manual, Oklahoma State University
Every cattle producer deals with down cows at some point in their career. The fate of the animal – in most cases – is grim. This episode of After the Abstract: a Bovine Science with BCI podcast features Dr. Brian Lubbers and Dr. Brad White evaluating a research article that explores how to increase the probability that a down beef cow gets back up. Thanks for tuning in and enjoy the show!
Welcome to BCI Cattle Chat! The experts begin the show by discussing the pros and cons of pulling bulls during/after the breeding season. Dr. Phillip Lancaster continues this edition of Cattle Chat by relaying all the known information about Leaky gut – a new and peculiar disease to cattle production. BCI student Luis Feitoza closes out the episode by talking with Dr. Brad White and Dr. Brian Lubbers about the capabilities of modern ultrasound machines in veterinary medicine.  Thanks for tuning in and enjoy the episode!
2:19 Removing Bulls: How to keep a tight calving window while adding value to cull cows
7:15 Leaky Gut: What it is, why it occurs, how it affects cattle, physical symptoms and prevention
15:12 Ultrasonography: capabilities, weaknesses and scenarios
For more on BCI Cattle Chat, follow us on Twitter 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!
Breeding season has begun for some and is just around the corner for others. Learn more about how stress affects fertility and the success of an artificial insemination or embryo transfer project in this edition of Herd Health. Dr. Brad White and Dr. Bob Larson discuss the causes of stress, management techniques that will help mitigate it and solutions that should lower a herd’s stress level.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Feed, Protein Tubs, Fertilizer-contaminated water
Mechanism
Rumen urease cleaves urea making ammonium, that reaction causes the rumen pH to climb. At pH >8, the reaction selects for ammonia that is absorbed and transported to the liver. The liver’s ability to metabolize ammonia is overwhelmed leading to hyperammonemia.
Signs
Rapid onset (20-60 minutes) of uneasiness, bloat, dyspnea, recumbency, paddling, cyanosis, and death. The rapid progression from consumption to death precludes the formation of any reliable lesions. Rumen pH will typically remain elevated for ~24, pH paper is a cheap and effective way for in-field evaluation.
Treatment
Treatment is based on lowering the pH and diluting the urea concentration. The most effective way to accomplish this is a rumen infusion of acetic acid (vinegar) and cold water. Animals should be triaged with treatment directed towards clinical animals that are not yet recumbent. Survivors generally have no lasting effects.
Diagnosis
Post-mortem diagnosis is based on ammonia concentrations in ocular fluid as well as rumen pH. Rumen content should be frozen ASAP because the ammonia will volatize off the sample.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Primarily a water deprivation syndrome – cattle can consume a significant amount of salt if fresh water is available. There are reports of mineral-starved cattle overeating mineral supplements with sodium used as an intake limiter.
Mechanism
As animals become dehydrated, the sodium concentration in the brain increases. The problem is upon rehydration, water follows the sodium into the brain resulting in cerebral edema and death to neurons.
Signs
Clinical signs are the same for lead poisoning and polioencephalomalacia and rooted in the central nervous system. Blindness is a hallmark of the syndrome and can help rule out causes of neurologic disease in cattle. Ataxia, head pression, recumbency, and death are also associated with the progression of clinical signs.
Treatment
The classic therapy for polio cases is injectable thiamine. Thiamine is a general neuro-protectant but is less effective in water deprivation cases than polio and lead encephalopathy. Slow rehydration of affected animals is the best approach. This can be a challenge on a herd basis and veterinarians and producers are often forced to get creative. Unlimited access to water will precipitate clinical signs and IV fluid therapy is not practical. Allowing water to run on a flat surface and forcing animals to drink slowly is ideal. Fluid deficits should be corrected over 12-24 hours.
Diagnosis
Diagnosis is based upon clinical signs, lack of a response to thiamine, characteristic lesions in the brain, and elevated brain sodium levels. It is important to submit both fixed and fresh brain in these cases as formalin-fixed brain is useless for sodium evaluation.
Scott Fritz, DVM, ABVT ToxicologistBeef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Alfalfa is the most common source of phytoestrogen exposure in the US. Other clover species can contribute to the total exposure.
Mechanism
Phytoestrogens bind to estrogen receptors in the animal leading to multiple effects.
Signs
The most economically important clinical sign associated with phytoestrogens is infertility. This is especially true in pre-pubescent animals that are exposed and can lead to life-long infertility by disrupting the estrogen-influenced maturation process. Prolapses have also been associated with feeding high levels of phytoestrogens. Phytoestrogens do not cause abortion.
Treatment
Remove the suspect source.
Diagnosis
Phytoestrogen evaluation of suspect feed source. Clinical improvement following removal.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Plants are typically fertilized, and drought-stressed, occasionally herbicide-treated plants can become more palatable and cause problemsÂ
Plants (Johnson grass, corn stalks, Sudan grass), water (especially with fertilizer contamination)Â
Mechanism
Rumen reduces nitrate to nitrite. Nitrite reduces the iron in heme forming methemoglobin that can’t carry oxygen – the affected animal become anoxic. Clinical signs will occur at 30-40% methemoglobin, death can occur when methemoglobin is >70%.
Signs
Rapid onset (30 minutes to hours) of weakness, bloat, ataxia, recumbency, cyanosis, and death. The rapid progression from consumption to death precludes the formation of any reliable lesions. Pregnant animals that survive the acute disease may abort 3-7 days after exposure.
Treatment
Methylene blue is the traditional antidote administered at 10 mg/kg of a 1% solution. There are withdrawal concerns for the use of methylene blue due to it being a potential carcinogen, FARAD should be consulted. Remove the suspect source.
Diagnosis
Brown discoloration of venous blood. Serum is a good antemortem sample, ocular fluid is the best post-mortem sample. Rumen content is not a good post-mortem sample as the rumen microbes will continue to degrade nitrate. Methemoglobin rapidly decays after collection so its diagnostic utility is limited.Â
1% nitrate in forage can result in acute deaths, 0.5% nitrate feed should not be fed to pregnant animals. 100 ppm in water can result in clinical signs. Laboratories that do feed and water analyses use different units to report the nitrate content, these units are different and it is imperative to recognize the differences.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Mycotoxins are secondary fungal metabolites that are produced by mold that colonizes damaged grains. Grains are the most common source, but occasionally certain forages can also be an issue.
Mechanism
There are only a few mycotoxins with recognized clinical effects, FDAs guidance tables are presented here.
Aflatoxin contamination has legal requirements for the sale of commodities
Guidance levels – fumonisins
Advisory levels – vomitoxin (DON)
No action, guidance or advisory levels for ochratoxin A or zearalenone have been established by the FDA in animal feeds (these 2 mycotoxins are handled on a case-by-case basis.
Action levels for total aflatoxins in livestock feed
Class of Animals
Feed
Aflatoxin Level
Finishing beef cattle
Corn and peanut products
300 ppb  
Beef cattle, swine or poultry regardless of age or breeding status
Cottonseed meal
300 ppb
Finishing swine over 100 lb.
Corn and peanut products
200 ppb
Breeding cattle, breeding swine and mature poultry
Corn and peanut products  
100 ppb
Immature animals
Animal feeds and ingredients, excluding cottonseed meal
20 ppb
Dairy animals, animals not listed above, or unknown use
Animal feeds and ingredients
20 ppb
Food and Drug Administration guidance levels for fumonisins in animal feeds.
Mycotoxin
Use
Total fumonisin
5 ppm (1 ppm) no more than 20% of diet)
Equids (horses, mules, donkeys) and rabbits
20 ppm (10 ppm) (no more than 50% of diet)
Swine and catfish
30 ppm (15 ppm) (no more than 50% of diet)
Breeding ruminants, breeding poultry and breeding mink
60 ppm (30 ppm) (no more than 50% of diet)
Ruminants older than three months being raised for slaughter and minks raised for pelt production
100 ppm (50 ppm) (no more than 50% of diet)
Poultry being raised for slaughter
10 ppm (5 ppm) (no more than 50% of diet)
All other species or classes of livestock and pet animals
The species, age, and health of the animal as well as the level and duration of exposure to the mycotoxin, will determine the magnitude of the effect of exposure. The effects can be subtle; including reduced weight gain and minor behavioral abnormalities such as feed refusal, or the effects can be severe, including reproductive dysfunction, organ failure, and death. Depending upon the magnitude of the exposure (duration and concentration), healthy animals can recover if the contaminated feed is removed from the diet.
Advisory levels for vomitoxin (DON) in livestock feed
Class of Animal
Feed Ingredients & Portion of Diet
DON Levels in Grains or Grain By-products and Complete Diet**
Ruminating beef and feedlot cattle older than 4 months
Grain and grain by-products*
10 ppm (10 ppm)**
Ruminating dairy cattle older than 4 months
Grain and grain by-products not to exceed 50% of the diet*
10 ppm (10 ppm)**
Ruminating beef and feedlot cattle older than 4 months, and ruminating dairy cattle older than 4 months
Distiller’s grains, brewers grains, gluten feeds, and gluten meals*
30 ppm (10 ppm beef/feedlot)** ( 5 ppm dairy)**
Chickens
Grain and grain by-products not to exceed 50% of the diet
10 ppm (5 ppm)**  
Swine
Grain and grain by-products not to exceed 20% of the diet
5 ppm (1 ppm)**  
All other animals
Grain and grain by-products not to exceed 40% of the diet
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Batteries, paint, older oils and greases, some solders, multiple others.
Mechanism
Lead has a variety of effects on different biochemical processes in the body. Generally, lead binds sulfhydryl groups deactivating some enzymes, lead competes with calcium ions replacing calcium in bone and altering conduction in nerves and muscle, lead also alters vitamin D metabolism and interferes with GABA activity in the CNS.
Signs
Clinical signs vary by species. In ruminants, acute lead exposures cause neurologic signs. Blindness is maybe the most recognizable and reasonably consistent sign. Other clinical signs include depression or hyperesthesia, ataxia, seizures, aggression, head pressing, muscle fasciculations, and death. Gastrointestinal signs including bloat and diarrhea may be appreciated.
Treatment
The classical antidote for lead poisoning in large animals is Ca-EDTA. Ca-EDTA can liberate lead from bone causing an increase in blood lead and worsening clinical signs. Chelation therapy in food animals is not recommended for multiple reasons including poor response to treatment, significant supportive care, and significant residue issues. In addition, there are no FDA-approved antidotes for food animals, thus, FARAD should be consulted prior to use. Regulations regarding lead exposure in food animals varies by state. The state veterinarian should be contacted, and some states will quarantine entire herds until blood lead concentrations drop below specified thresholds.
Diagnosis
Diagnosis is heavily dependent upon elevated concentrations of lead in the body. Ante-mortem testing is easily accomplished with whole blood. Postmortem sampling should include liver and kidney lead concentrations. Histologically, lead exposure can cause polioencephalomalacia, it is important to consider water deprivation/salt poisoning, and elevated dietary sulfur in clinical cases.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
Water: surface water (ponds especially in late fall or drought years) in some areas of the country and ground water (wells) in others.Â
Feed: Some co-products are recognized sources like DDGs, molasses, etc.Â
Poultry litterÂ
Mechanism
Dietary sulfur is converted by the rumen microbes to hydrogen sulfide gas. H2S is eructed and inhaled and probably absorbed across the rumen wall. Hydrogen sulfide is a systemic poison that interrupts cellular metabolism. Tissue with high energy demand, like the brain, are first affected.
Signs
Classical clinical signs include ataxia, blindness, and head pressing. These typically occur 1-4 weeks after starting cattle on a high-sulfur diet.
Treatment
Thiamine is the treatment of choice for polio cases. Corticosteroids, NSAIDs, and diuretics have been recommended but their efficacy is unclear, and the adverse effects of their use may outweigh any benefit they have.
Diagnosis
Response to thiamine administration is a strong diagnostic indicator. Histologic lesions are identical to those caused by lead toxicosis and water deprivation/sodium ion toxicosis. Brain sodium and liver and kidney lead concentrations should be analyzed to rule out these other causes. Thiamine has shown to be beneficial in cases of lead encephalopathy.
Scott Fritz, DVM, ABVT Toxicologist Beef Cattle Institute Kansas State University Scottfritz@vet.k-state.eduÂ
Sources
CCA (chromated copper arsenate) treated lumber, especially after burning, cattle seem to find the ashes palatable.Â
Arsenic-containing insecticides
Mechanism
Most heavy metals exert their toxic effects by substitution for other metals. Arsenic is no different. Trivalent arsenicals interrupt the TCA cycle while pentavalent arsenicals uncouple oxidative phosphorylation. Both mechanisms interrupt cellular respiration and produce an energy deficit at the cellular level. Rapidly dividing cells and those with a high energy demand are first affected.
Signs
Clinical signs and risk are heavily dependent upon the valence of the arsenic involved. Generally, clinical signs are severe and associated with the gastrointestinal system. Colic, weakness, and diarrhea, often hemorrhagic, are common. Sever neurologic signs can predominate in acute exposures to readily available sources. Ataxia, staggering, recumbency are common in these cases.
Treatment
The classic antidote for arsenic poisoning is dimercaprol in companion animals but is not overly effective after clinical signs are observed so it’s use in clinical cases is limited. Thioctic acid is more effective in cattle but is not approved for use in food animals. FARAD should be consulted if used. Excretion is rapid and, unlike lead, arsenic is readily cleared after exposures.
Diagnosis
Diagnosis is heavily dependent upon elevated concentrations of arsenic in liver and kidney. Both organs should be submitted and it is important to recognize that given the rapid excretion of arsenic, animals that live for long periods after exposure may not have identifiable concentrations in these organs. Diagnosis can be supported by histologic examination of tissues, especially the kidney and gastrointestinal tract. Suspect material can also be analyzed.Â
