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 environment.

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 decisions.

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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.

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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 effects are relatively small and context-dependent.

Article Discussed: HERE

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 practices may influence herd outcomes more than frequent testing.

Article Discused: https://pubmed.ncbi.nlm.nih.gov/41472190/

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 vaccine at synchronization is safe in well-vaccinated adult cows, though results may not apply to naïve heifers.

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On this episode of Tox Talk, Dr. Brad White and Dr. Scott Fritz discuss a case where eight bred cows were moved into a barn ahead of a winter storm and were found dead the next morning. While initial concerns focused on the barn environment, testing revealed the cause was acute nitrate poisoning from newly introduced millet hay containing high nitrate levels. Nitrate toxicity can cause rapid death, often within hours, and may leave few obvious signs. This case is a reminder to consider what has changed when sudden losses occur, especially feed sources. Certain forages, including millet and other stress-grown crops, can accumulate nitrates, and toxicity persists after baling. Testing unfamiliar or newly purchased hay can help prevent devastating losses.

In this episode of Diving into Diets, the discussion examines how different phosphorus and calcium diets affect phosphorus retention, milk composition, calf growth, and bone status in beef cattle. While cows on lower-phosphorus diets maintained milk production and calf growth in the short term, they mobilized phosphorus from bone, unlike cows on high-phosphorus, high-calcium diets. The takeaway is that cows are resilient and can tolerate short-term deficiencies, but inadequate long-term mineral intake may eventually impair performance, underscoring the need for appropriate supplementation.

Article Discussed: https://era.dpi.qld.gov.au/id/eprint/14721/1/AN24216.pdf