Listen to veterinary professionals from the Beef Cattle Institute at Kansas State University talk about a variety of topics within cattle health, nutrition, reproduction, and science. New episodes of Bovine Science with BCI are posted each Monday.
Reading the feed…
This episode explores the role of vitamin A in beef cow-calf systems and examines why some calves develop low vitamin A levels and respiratory disease even while grazing alongside cows on green pasture. The discussion highlights that vitamin A nutrition is more complex than simply having access to lush forage, because cattle primarily consume beta-carotene from grass, which must be converted into usable vitamin A by the body. A major takeaway is the importance of colostrum as the primary source of vitamin A for newborn calves. Because very little vitamin A is transferred across the placenta, c
This episode reviews a 2026 Canadian study that evaluated whether vaccinating beef calves against bovine coronavirus could reduce pre-weaning respiratory disease in a commercial cow-calf herd with a history of respiratory problems. The researchers compared vaccinated and non-vaccinated calves under real-world ranch conditions, making the findings especially relevant for producers facing similar challenges. Results showed that vaccinated calves had lower odds of requiring treatment for respiratory disease before turnout, and overall disease rates tended to be lower in vaccinated groups. The stu
This case study examines a tragic incident in which 14 open heifers died within hours of being separated from a larger group following pregnancy testing. The heifers had been placed in a familiar holding pasture with a functioning water source and secure fencing, leading managers to initially believe the environment was safe. When all 14 animals were found dead later that day, investigators quickly ruled out infectious disease and focused on acute toxic causes due to the rapid onset and 100% mortality rate. Potential causes considered included nitrate toxicity, cyanide poisoning, urea exposure
This case study follows the investigation of a puzzling eye disease outbreak affecting approximately 10% of a group of 1,200 stocker cattle shortly after processing and placement on pasture. The affected animals developed severe eye lesions, including corneal cloudiness, swollen eyelids, redness, and inflammation, but lacked many of the classic ulcers typically associated with pinkeye. Because cases appeared almost simultaneously across numerous pastures separated by up to 90 miles, investigators quickly determined the outbreak did not fit the pattern of a contagious, spreading disease. Instea
This episode examines a study evaluating different nutritional strategies for developing replacement heifers and their impact on puberty attainment. Researchers compared traditional low-gain and high-gain feeding programs with two “stair-step” nutritional approaches that alternated periods of higher and lower energy intake. The goal was to determine whether strategic feeding could achieve the same reproductive outcomes as intensive feeding while using fewer resources. Results showed that the first stair-step program, which provided a higher plane of nutrition immediately after weaning followed
This episode examines a study investigating whether the physical size of dry lot pens affects the development of replacement heifers, even when animal density remains the same. Researchers compared heifers housed in a standard-sized dry lot, a larger dry lot with the same space per animal, and a pasture-based control group. While growth performance and weight gain were similar across treatments, important differences emerged in behavior, stress indicators, and reproductive development. Heifers housed in the smaller dry lot reached puberty approximately 20–30 days later than those in the larger
This case study examines a sudden and devastating loss in which five cows and two calves died shortly after being moved to a dry lot following the calving season. The affected group consisted of only six cow-calf pairs that had been separated because they were open or had calved late, making the rapid mortality highly suspicious for a toxic exposure rather than an infectious disease. Necropsies revealed few significant findings, while the only surviving cow showed severe neurological signs, including tremors, vocalization, and an inability to stand. Investigators focused on feed and water as t
This episode examines research exploring why some cow-calf producers adopt written grazing management plans while others do not. The study was motivated in part by sustainability goals aimed at improving grazing land management, soil health, water infiltration, and drought resilience through more structured planning. Researchers analyzed survey data from producers across the United States to identify factors associated with both written grazing plans and intensive grazing practices. Results showed that larger land holdings were associated with a greater likelihood of having a grazing managemen
This discussion examines a research study focused on improving long-term profitability in cow-calf operations through better heifer selection. The study used economic modeling and field data to evaluate three key factors: feed efficiency, longevity, and heterosis (hybrid vigor). Results showed that cows with greater genetic diversity consistently generated higher returns, largely due to improved reproductive performance and overall herd productivity. Longevity also played a critical role, as cows that remained productive in the herd longer were able to spread their development costs over more
This episode explores a research study evaluating whether sterile saline can effectively replace phosphate-buffered saline (PBS) for collecting samples used in Tritrichomonas PCR testing. The discussion highlights a non-inferiority trial design, which differs from traditional statistical approaches by testing whether one method is not meaningfully worse than another. Researchers created controlled samples with varying concentrations of organisms and compared detection results using both saline and PBS. Results showed no significant difference in detection performance between the two media, and
This discussion explores the concept of systems thinking in beef cattle production and how it expands beyond traditional population medicine approaches. Systems thinking focuses on understanding how multiple interconnected factors—such as nutrition, environment, disease exposure, and management practices—interact over time to influence herd health and productivity. Many cattle health and performance issues develop gradually, often involving delayed cause-and-effect relationships that can span months or even generations. The approach also recognizes that cattle may pass through multiple owners
This case study from a bovine science discussion examines a sudden and alarming incident in which 12 cows and 2 calves died within 12 hours of routine pre-weaning processing. Initially, the deaths raised concerns about vaccine reactions, toxic exposure, or handling stress, but the pattern of mortality did not align with typical causes. Adult cows, which only received topical parasite treatment, were more affected than calves that received vaccines, further complicating the diagnosis. A necropsy revealed elevated sodium levels in brain tissue, pointing to water deprivation as the underlying iss
In this episode of BCI Cattle Chat, the hosts explore what the future may hold for the beef industry, discussing trends in cattle size, production inputs, and market prices. They examine the realities of cow-herd expansion and consider how policy decisions could influence cattle production in the years ahead. The conversation also highlights recent research on liver abscesses in feedlot cattle, including how factors such as diet composition, grain processing methods, and days on feed may affect their prevalence and economic impact. Finally, the beef cattle experts weigh the concept of more dua
This episode of After the Abstract on Bovine Science with BCI reviews a 2026 study examining bovine leukemia virus (BLV) in cow-calf herds and its potential effects on reproduction, culling risk, and calf weaning weights. The hosts discuss findings showing that although BLV prevalence was very high in the studied herds, standard ELISA-positive status was not significantly associated with poorer pregnancy rates, increased culling, or lower weaning weights. They also explore proviral load measurements, noting that cows with the highest viral loads had slightly lower pregnancy rates, though the p
In this episode of Diving Into Diets on Bovine Science with BCI, Dr. Brad White and Dr. Philip Lancaster discuss a 2026 study examining whether lower-protein finishing diets can improve performance in long-fed feedlot steers. The researchers compared industry-standard 13.5% crude protein diets to reduced 11.5% crude protein diets over roughly 206 days on feed and found that cattle on the lower-protein diet achieved slightly heavier carcass weights and improved dressing percentages without sacrificing overall growth. The conversation explores how excess dietary protein may increase the animal’s
In this episode of Tox Talk on Bovine Science with BCI, Dr. Brad White and Dr. Scott Fritz discuss a case where a group of cow-calf pairs was turned out onto pasture, and several adult cows died suddenly while calves remained unaffected, pointing away from infectious disease. With no lesions found on necropsy, the veterinarians focused on toxic causes, especially those affecting cardiac function, oxygen delivery, or neurotransmitters. Clues from rumen contents and a pasture walk led to the discovery of Japanese yew trimmings in a dump pile, a highly toxic plant that causes rapid cardiac death.
In this episode of Tox Talk with BCI, Dr. Brad White and Dr. Scott Fritz walk through a challenging case where 75 cows were turned into a new pasture and left unchecked for two weeks, resulting in 22 deaths. The surviving cattle showed jaundice and severe skin damage linked to secondary photosensitization from liver injury. Through diagnostics and pasture investigation, the cause was identified as Lantana camara toxicity, leading to cholestasis and liver failure. The discussion highlights the importance of pasture evaluation, monitoring, and recognizing toxic plant risks in grazing systems.
On this episode of After the Abstract on Bovine Science with BCI reviews a recent study on pregnancy loss in crossbred beef cows, focusing on factors that influence whether pregnancies are maintained after conception. The vets highlight that estrus expression at the time of artificial insemination, cow body weight, and season all play significant roles, with lighter cows, those not showing estrus, and those bred in the dry season experiencing higher loss rates. They also emphasize that changes in body condition after breeding, especially losing condition, are strongly associated with increased
In this episode of Diving into Diets on Bovine Science, Dr.Brad White and Dr. Phillip Lancaster discuss a 17-year study comparing fertilizing pasture versus supplementing cattle on smooth bromegrass and found that supplementation led to higher daily gains and greater gain per acre than either fertilized or unfertilized systems. Fertilization increased carrying capacity but did not improve individual animal performance compared to the control. Importantly, supplementing cattle maintained soil nitrogen levels similar to those in fertilized pastures, likely due to manure recycling, with no long-t
In this episode of Tox Talk on Bovine Science, Dr. Brad White and Dr. Scott Fritz discuss a case where multiple two-month-old calves in a dry lot died with minimal clinical signs. Initial differentials included infectious disease, nutritional issues, and ryegrass staggers, but necropsy and testing were largely unrewarding. Ultimately, elevated tissue lead levels confirmed lead poisoning, even though no clear source was identified. The case highlights the importance of considering lead toxicity in young calves with neurologic signs, especially when they have access to areas outside their normal
In this episode of Herd Health on Bovine Science, the experts discuss a recent study on factors associated with bull breeding soundness exam (BSE) failure. The veterinarians explain that both intrinsic factors, such as age and prior failure, and extrinsic factors, such as season and environmental conditions, influence whether a bull passes or fails. They highlight that sperm morphology is one of the most important indicators of fertility, often more predictive than other measures. Overall, the episode emphasizes interpreting BSE results in context to make better management and culling decision
In this episode of BCI After the Abstract, the veterinarians explore a pharmacokinetic study on the use of methylene blue in cattle to determine safe withdrawal periods after treatment. The experts walk through how researchers tracked drug levels in blood, milk, and tissues to estimate when residues fall below safe thresholds. They emphasize that previous guidance lacked data, forcing veterinarians to rely on highly conservative withdrawal times. With this new evidence, practitioners can better balance effective treatment of nitrate toxicity with responsible residue avoidance in food animals.
In this episode of Diving Into Diets on Bovine Science with BCI, the experts discuss a 2025 meta-analysis comparing organic and inorganic trace mineral supplementation in beef cattle during preconditioning and feedlot receiving. They explain the biological differences between mineral sources and review results from about 20 studies included in the analysis. Overall, organic minerals showed a small improvement in average daily gain, but no effect on cattle morbidity. The discussion highlights that while organic minerals may provide slight performance benefits in certain situations, the overall
This episode of After the Abstract reviews a 2025 study on managing Johne’s disease in beef cattle using different testing and culling strategies in a modeled 300-cow herd. The results showed that testing cows every six months reduced disease prevalence the most, but was the least profitable strategy, even compared with doing nothing. Testing every 24 months provided the best economic balance, lowering prevalence moderately while maintaining the highest net return. The discussion also emphasizes that the prevalence of Johne’s disease in purchased replacement cattle and strong biosecurity pract
In this episode of Herd Health, the experts review a 2025 study evaluating whether modified live virus (MLV) vaccines can be given at the time of CIDR placement for timed AI in beef cows. In previously vaccinated, multiparous cows about 80 days postpartum, administering an MLV vaccine at synchronization did not negatively affect estrus response, AI pregnancy rates, overall pregnancy rates, pregnancy loss, calving timing, or calf weaning weights. Total pregnancy rates were around 95%, with no significant differences between vaccinated and control groups. The findings suggest that giving an MLV
