Cattle Chat: Newborn Fly Control, Bovine Science, Castration Research

Date: September 5, 2025
Host: Brad White with BCI Cattle Chat Team (Bob, Philip, Dustin, Scott)
Podcast: Beef Cattle Institute at Kansas State University

Episode Overview

This episode dives into practical health and management challenges facing beef producers: effective fly control and deworming in newborn calves, insights from real-world bovine science cases, and an in-depth discussion of recent research on the effects of castration timing on cattle performance and market prices. Using listener questions and case-based discussion, the BCI team blends science, economics, and on-the-ground experience to provide actionable advice for cattle producers.

Key Discussion Points & Insights

[04:15] Listener Question: Fly Control & Deworming for Newborn Calves

• Deworming Newborns:

  • Bob: Deworming at birth isn’t typically necessary; internal parasite burdens develop over time and are generally addressed starting at 1–3 months of age depending on seasonal and geographic parasite risks.
    • Quote @04:19:

      "They will pick up parasites pretty soon... we're aiming for that two month of age, but you get some on each side and we do see a benefit deworming at that age... Not necessarily birth."

  • Important to match deworming strategies to regional parasite prevalence—southern climates may require more vigilance than drier, hotter regions.

• Fly Control in Newborns:

  • Scott: Dosing is especially critical—products labeled for 1,200+ lb cows can overdose an 80 lb calf.
    • Topical sprays are safer than systemic pour-on products for neonates.
    • Ear tags pose a physical size issue and may have weight limits on the label.
    • Quote @05:57:

      "If you're mixing products to apply to a 1400 pound cow and you've got a 80 pound newborn calf, then you got to be pretty careful how you dose that animal because it's all going to be based on body weight."

  • Bob: Address fly control at the herd level—adult cows are major sources of flies.
    • Face flies (look like house flies, spend more time off the animal) vs. horn flies (smaller, spend life on cattle).
    • Environmental management—clean calving areas and spreading out calves can help.
    • Quote @08:50:

      "Horn fly spends basically its entire life on an animal... Face flies are really frustrating because they... spend most of their time away from the animal... so a lot of times what we're really talking about with face flies is trying to do something that repels them."

• Summary Insight @09:58:

  "Might want to treat those calves, be sure it's dose appropriate for that small weight, but also look at the rest of the herd in the environment to get a full fly control plan." (Brad)

[10:34] Bovine Science with BCI: Case-Based Learning in Bovine Practice

• Toxicology Sampling Guides:

  • Scott: Discussed a downloadable sampling guide to help practitioners handle toxic exposure allegations in the field.
    • Quote @10:34:

      "We put together a sampling guide. So if you have a toxic exposure... kind of the samples you need to select, how those need to be stored and transported..."

• Reproduction Cases:

  • Bob: Most cases come via practitioner referrals about unusual repro failures.
    • Investigative process: start with "Who didn’t get pregnant? When didn’t they get pregnant?"—patterns in timing and grouping often reveal underlying problems.
    • Quote @11:26:

      "The first part of the investigation is just figuring out, well, who didn't get pregnant and then another aspect... is when didn't they get pregnant?"

• Nutrition Research Summaries:

  • Philip: Selects literature for the podcast based on applicability and novelty—focuses on research that offers direct, field-relevant takeaways.

• Platform Info:

  • Episodes and guides available via BCI website or podcast platforms ([14:31]).

[14:47] Castration Timing Research & Economic Impact

• Article Discussed: Beck et al., Applied Animal Science, 2025—Meta-analysis of health and performance outcomes following castration at different ages.

  • Findings:
    • Bulls are 1.16x more likely to have chronic morbidity and 2.3x more likely to have BRD mortality than steers.
    • Recommended a 15% price discount on bulls vs. steers when considering total health and performance costs; actual observed discounts are often smaller (3–8%).

• Market Discounts:

  • Dustin:
    • Kentucky study: ~3% discount on bulls vs. steers (2010–2021, 550 lb animals).
    • Oklahoma State: 6–8% discount, heavier bulls penalized more (2020–2022).
    • Quote @16:00:

      "A little over 3% in that study... more recent study... discounts, depending on weight ... from 6% at a 375 pound animal to about 8% at a 875 pound animal."

  • Brad:
    • Study suggested the price penalty for bulls should be closer to 15% to account for health and performance impacts.
    • Quote @16:41:

      "For the BRD consequences, morbidity and mortality, that there should have been a two and a half percent discount...when you factor in BRD and performance...they thought the bulls should be sold at a 15% discount."

• Industry Recommendations:

  • Scott & Group Consensus:
    • Early castration (birth to 2 months) minimizes morbidity, performance loss, and price discount.
    • If castrating at weaning or later, performance loss is greater and recovery is slow.
    • Quote @18:29:

      "The first answer is castrate bulls earlier... at two months of age. And I think that there's quite a bit of work that would support ... you should have, in theory, lower morbidity associated with that."

  • Bob:
    • As a buyer, would prefer calves castrated young; if not, would rather buy intact bulls and manage castration in-system than buy recently castrated calves due to higher risk and uncertainty.
    • Quote @19:29:

      "My first preference would be for steers that had been steered, you know, at a young age, 2 months of age or younger... I would almost prefer a bull that then I would bring into my system, castrate him..."

• What Should Producers Do if Close to Weaning with Bulls?

  • If only weeks before sale: prefer to sell as bulls (take the discount, let buyer manage).
  • If backgrounding/retaining for months: castrate early in that window to allow time for weight recovery.
  • Philip: Considers timing and market cycles—delaying sale after late castration can result in additional seasonal price loss.
    • Quote @21:06:

      "It's going to take them, they're going to lose weight for several weeks...by the time I'm ready to sell them, I'm at the bottom of the, the fall market."

• Systemic Challenge:

  • Industry segmentation means disease and performance risks shift to whoever holds bulls the longest—even when everyone knows early castration is better, incentives sometimes don’t align for optimal industry health.

Notable Quotes & Memorable Moments

• On college football rivalry (Icebreaker):
  • Scott [02:44]:

    "I don't care about either team. And frankly, it would be cool if they both lost, but I'd still go watch the game."

• On tag dosing for newborns:
  • Scott [08:17]:

    "It's challenging to calibrate that dose because those tags are one dose per tag, right?"

• On industry reality:
  • Brad [22:14]:

    "And it's one of the real challenges with the segmented industry. ... I might do better, but the next guy's going to straw. And that becomes a real problem from an industry standpoint."

• On value-added opportunities:
  • Dustin [23:22]:

    "There's a value add opportunity, right, by rem, a value add by subtraction of two pieces."

Important Timestamps

• [04:15] Listener Q: Fly control and deworming in newborns
• [05:57] Dosing concerns for fly products in neonates
• [10:34] Bovine Science with BCI: sampling guides and case-based learning
• [14:47] Discussion of Beck et al. research on castration, BRD, and performance
• [16:00] Dustin reviews market price discounts for bulls vs. steers
• [18:29] Group consensus: “Castrate earlier” is best
• [19:29] Bob’s purchasing priorities for calf buyers
• [21:06] Market cycle and recovery challenges with late castration
• [22:14] Industry-wide coordination and incentive challenges

Summary

This episode arms producers with practical know-how for managing neonate fly and deworming programs, underscores the value of timely, precise field sampling for diagnostics, and unpacks the economic—and animal welfare—arguments for castrating bulls early. Through recent research and real-world case experience, the BCI team emphasizes the sometimes-misaligned incentives in a segmented cattle industry, and advocates for management decisions that minimize disease risk, performance drag, and price penalty—benefiting both the producer and the broader beef industry.

Find Bovine Science with BCI:

• On the BCI website or any major podcast platform