Bovine Science with BCI

This episode examines how beef producers can improve parasite control by using dewormers strategically rather than treating all cattle routinely. Drawing from a 2026 literature review authored by researchers at Mississippi State University, the discussion highlights how internal parasites can significantly affect cattle health and productivity, particularly in younger animals. Young calves, stockers, and developing heifers typically benefit the most from deworming because they carry heavier parasite burdens and are more susceptible to performance losses than mature cows. The hosts explain that parasite risk varies greatly by geography, with warm, humid regions generally experiencing higher parasite pressure than drier areas. They also stress that mature cattle often develop some resilience to parasite infections, meaning routine treatment may not always provide measurable returns in older animals. Another major focus is parasite resistance. Overusing dewormers can select for resistant parasite populations, reducing the long-term effectiveness of valuable treatment tools. The discussion emphasizes that parasite control should involve more than just selecting a product, incorporating pasture management, grazing rotations, environmental conditions, and nutritional management.The hosts also caution that diagnostic tests such as fecal egg counts must be interpreted carefully because parasite burdens, animal performance, and test results do not always align perfectly. Working with veterinarians to develop region-specific control programs is strongly encouraged. Ultimately, the review concludes that there is no one-size-fits-all parasite management strategy. Instead, producers should focus on using dewormers at the right time, in the right animals, and only when they provide meaningful health and economic benefits, helping preserve these tools for future use.

This episode examines whether feeding additional vitamin A to cows before calving can improve the vitamin A status of their calves. Reviewing two dairy research studies, the hosts explore how late-gestation supplementation affects vitamin A levels in colostrum, milk, and newborn calves. In the first study, cows received vitamin A at levels slightly above recommended requirements, but researchers found no increase in colostrum vitamin A content and no meaningful improvement in calf blood vitamin A concentrations. The second study supplemented cows with much larger amounts of beta-carotene, a precursor to vitamin A. While this significantly increased beta-carotene levels in colostrum and resulted in more calves having detectable beta-carotene after birth, it still failed to increase retinol, the active form of vitamin A, in calf blood samples. The findings suggest that transferring additional vitamin A from cow to calf through maternal supplementation is more difficult than many producers might expect.The discussion reinforces that newborn calves receive very little vitamin A through placental transfer and rely heavily on colostrum as their primary source after birth. However, even feeding cows three to four times the recommended vitamin A levels produced only modest changes in calf vitamin A status. The hosts also compare these dairy studies to previous beef cattle research, noting that very large supplementation rates may be required before measurable improvements occur in calves. As a result, simply increasing vitamin A intake in pregnant cows may not be an efficient solution for improving calf vitamin A status. The episode concludes by raising important questions about whether calves born to cows consuming stored hay during late gestation may benefit from alternative strategies, such as direct vitamin A supplementation, and emphasizes the need for additional research to better understand vitamin A requirements in modern beef production systems.

This episode examines a 2026 study that explored whether pre-breeding behavior can predict which bulls will sire the most calves in multi-sire breeding pastures. Researchers fitted bulls with collars containing accelerometers and proximity sensors to objectively measure activity levels and social interactions before the breeding season. The goal was to determine whether behavioral traits such as activity, social connectedness, and interaction patterns were associated with a bull’s eventual siring capacity. The study found that more active bulls tended to sire more calves, and bulls that were more socially connected within the group also appeared to have greater breeding success. Researchers used complex network-analysis measurements, including eigenvector centrality and relative strength, as indicators of social influence and interaction among bulls. Bulls with more diverse interactions across the bull group generally had higher siring capacity than bulls that spent most of their time with only a few herd mates.The hosts found the concept particularly intriguing because previous efforts to predict breeding success often relied on subjective observations, while this study used objective monitoring technology. However, they also highlighted several limitations, including a relatively small sample size, missing sensor data, differences in bull grouping between years, and challenges associated with bulls entering or leaving breeding groups due to injury.Another important finding was that some behavioral traits, especially activity level and social connectedness, showed moderate repeatability from year to year, suggesting they may reflect inherent characteristics of individual bulls rather than temporary conditions. The hosts emphasized that while the results are promising, the study should be viewed as an early step rather than definitive evidence. They concluded that larger studies across more herds and breeding environments will be necessary to determine whether wearable technology can reliably help producers identify the most effective breeding bulls before turnout.

This episode explores how vitamin A nutrition in late-gestation cows affects both maternal health and the vitamin A status of newborn calves. The discussion builds on previous conversations about calf vitamin A deficiencies, emphasizing that colostrum is the primary source of vitamin A for newborn calves and that deficiencies early in life can persist for weeks or months. The hosts review two research studies examining how vitamin A and its precursors are affected by rumen fermentation. The first study found that beta-carotene, the precursor to vitamin A found in green forages such as alfalfa, remains relatively stable during rumen fermentation, suggesting that high-quality green hay can be an excellent source of vitamin A for pregnant cows. They note that protecting hay from sunlight is important because ultraviolet light accelerates degradation of carotenoids, reducing the vitamin A value of stored forage. The second study evaluated supplemental vitamin A and found that degradation of common vitamin A supplements increased substantially in higher-concentrate diets. In some cases, only about 30% of the supplemented vitamin A remained after 24 hours of fermentation in rumen fluid from cattle fed more concentrate-heavy diets. Interestingly, the form of the supplement had little effect on degradation, while diet composition had a much larger influence. The practical takeaway is that producers should focus first on preserving and feeding high-quality green forage during late gestation, while also considering whether additional vitamin A supplementation may be necessary when hay quality is poor or concentrate feeding levels increase. The episode reinforces that thoughtful forage management and nutrition planning before calving can improve vitamin A delivery to cows, support colostrum quality, and help set calves up for better health after birth.

This case study examines a situation where a producer attempted to control a heavy fly burden by spraying cattle with a topical insecticide, only to have several cows develop severe toxic signs within hours. Affected animals became recumbent, excessively salivated, developed diarrhea, experienced respiratory distress, and showed muscle tremors and weakness, raising immediate concerns about insecticide toxicity. The investigation focused on two common groups of insecticides used in cattle: organophosphates and pyrethroids. Because the cattle exhibited the classic “SLUD” syndrome of excessive salivation, lacrimation, urination, and defecation, the evidence pointed strongly toward organophosphate poisoning. Review of the product label revealed that the insecticide had been mixed at a dramatically higher concentration than recommended. Instead of being diluted according to animal-use directions, the concentrate was mixed at a strength far closer to premise-spray concentrations, resulting in massive overdosing. The discussion highlights how many insecticide products contain multiple sets of directions depending on whether they are being used on facilities, back rubbers, or directly on animals, making careful label review essential. Once toxicity was identified, treatment focused on immediately washing cattle with detergent and water to remove residual insecticide from the skin and administering atropine to reduce secretions and support breathing. Fortunately, the affected cattle recovered after treatment, demonstrating the importance of rapid recognition and intervention. The case serves as a reminder that insecticides are highly potent compounds designed to affect nervous system function and must be handled with extreme care. Proper dilution, careful reading of product labels, and attention to species-specific application instructions are critical to preventing potentially fatal mistakes during fly control programs.