Real Science Exchange-Dairy

Introductions and Symposium PreviewsDr. Andrew Lapierre shares the nearly 50-year history of CNCPS, and Dr. Jonas de Souza previews his work on fatty acid modeling. Dr. Veridiana Daley reviews milk protein modeling, amino acid nutrition and new technologies that could sharpen decision-making. (00:00 – 10:45)Models in the FieldThe consulting nutritionists explain how they use models' day to day. They discuss how ration software has evolved and why model outputs still need practical farm management and observation behind them. (10:46 – 15:12)NASEM vs. CNCPSThe panel compares empirical and mechanistic models. Models are the best interpretation of available data, not perfect pictures of biology. That's why it's critical to understand each model's assumptions before acting on its recommendations. (15:13 – 19:25)Protein and Rumen Degradable Protein PredictionsNASEM and CNCPS often reach different answers because they rely on different assumptions, microbial compositions and prediction methods. Neither is perfect, but both are useful for evaluating amino acid supply and nutrient responses. (19:26 – 24:08)Modeling the Modern Dairy CowGenetic progress has raised production potential, yet many post-absorptive efficiency assumptions still come from older datasets. The panel names nutrient use efficiency and variable animal responses as key areas for future research. (24:09 – 29:46)Making Practical Ration ChangesNutritionists use models to guide gradual ration changes within real-world constraints. They also point out that management decisions can affect performance as much as the diet itself. (29:47 – 33:32)Adding Sensor Data to ModelsRumination, rumen health and other precision dairy sensor data could improve intake predictions, flag health events and support nutritional decisions. (33:33 – 37:43)Dry Matter Intake and Forage QualityThe panel looks at dry matter intake optimization and forage quality challenges. They also ask whether maximizing intake is always the most profitable strategy. (37:44 – 43:29)Improving Feed Libraries and Response ModelsThe group sees room to expand response modeling and improve feed libraries. They also want to better characterize ingredients and add amino acid and fatty acid data, all while validating models against research and field datasets. (43:30 – 58:41)The Future of Nutritional ModelingLooking ahead, the panel discusses better fatty acid and amino acid prediction systems, sensor integration, artificial intelligence and stochastic modeling. They also call for stronger collaboration between researchers and field nutritionists, with better data and ongoing validation driving progress. (58:42 – End)ConclusionPlease subscribe and share with your industry friends. Invite more people to join us at the Real Science Exchange virtual pub table. In addition, please be sure to register for our upcoming Real Science Lecture Series webinars.Finally, if you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to [email protected]. Include your size and mailing address, and we’ll mail you a shirt.

Host Scott Sorrell is joined by Dr. Billy Brown (Kansas State University) and Carson Corwin (Kansas State University). The episode centers on Carson Corwin's presentation, "Effect of prenatal rumen-protected choline on dam feeding behavior and offspring mammary development." Carson Corwin outlines the study design, which evaluated multiparous cows fed a rumen-protected choline supplement during the 21-day prepartum period. Individualized feeding bunks equipped with RFID technology were used to measure intake and feeding behavior, including meal timing, meal intervals, meal size, and number of meals. The team also followed heifer calves and collected mammary ultrasound images on days 1, 42, and 84. (03:15 – 05:43) Discussing the results, Carson highlights what he describes as the most exciting finding: increased mammary parenchyma area in calves born to supplemented dams. The researchers also observed a tendency for a greater parenchyma-to-fat-pad ratio, which they describe as an indicator of greater mammary system development potential. Dr. Brown explains that the effect was observed across the evaluation period rather than at a single time point and notes an approximately 10% difference in the measured area. (05:44 – 07:49) Dr. Brown places the findings into the context of earlier research that reported benefits in calf growth, immune responses, and longer-term development. He explains that previous studies and observations have suggested potential downstream production advantages, although some of those observations remain unpublished. The speakers emphasize that the current work is an early step toward understanding possible biological mechanisms and that additional follow-up is needed to determine how these developmental differences may relate to later-life performance. (07:50 – 08:59) When discussing why prenatal choline exposure might influence calf development, Dr. Brown notes that the mechanism remains a "black box." He says the team's best speculation is that epigenetic factors may be involved, but stresses that researchers have not yet identified a definitive explanation. The conversation also turns to future work, including continued monitoring of the calves and plans to evaluate metabolic factors that could provide further insight into observed responses. (09:00 – 09:41) Looking ahead, Carson shares plans for a new project evaluating a yeast supplement fed to prepartum cows beginning earlier in the dry period, with a focus on calf immune response and colostrum quality. The episode closes with reflections on future career goals and the researchers' enthusiasm for continuing to investigate how prenatal nutritional interventions may influence calf development. (09:42 – End) Throughout the episode, the panel reinforces a central message: prenatal nutritional strategies may have effects that extend beyond the dam, but further research is needed to understand the biological mechanisms and long-term implications of those responses. If you enjoyed this episode, subscribe and share it with your industry colleagues so they can join us at the Real Science Exchange virtual pub table. Don't forget to register for our upcoming Real Science Lecture Series webinars. Finally, if you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription. Then, email a picture to [email protected]. Include your size and mailing address, and we'll mail you a shirt.

The episode begins with introductions from Dr. Addison Carroll and Dr. Kelly Mitchell, who share their educational backgrounds, research experience, and current roles at Washington State University and Elanco Animal Health. They also preview the Tri-State Dairy Nutrition Conference session featuring presentations from Dr. Carroll, Dr. Edward Rico, and Dr. Kelly Nichols. Dr. Carroll's presentation, Nutrient Variation in Feed Delivery and the Impacts on Lactating Dairy Cows, provides the foundation for the conversation, examining how nutrient deviation can influence dairy cow performance and why understanding variation matters for effective feeding management. (00:00 – 03:26)Nutrient variability can begin long before a dairy ration reaches the cow. Dr. Carroll explains that inconsistencies can originate from feed composition, ration formulation, ingredient loading, feed mixing, and cow behavior. Identifying where variation enters the feeding process, along with its potential economic consequences, can help dairy producers uncover opportunities to improve feed consistency and overall herd management. (03:27 – 05:20)Breaking the dairy feeding process into four major areas, Dr. Carroll highlights variation associated with ration formulation, feed loading, feed mixing, and animal consumption. Human involvement in loading and mixing can be a significant source of inconsistency, while Dr. Mitchell notes that small variations at individual stages can compound throughout the feeding process. Understanding these sources provides a clearer picture of how the ration formulated by the nutritionist may differ from what ultimately reaches the cow. (05:21 – 08:26)Drawing on research involving eight dairies ranging from 3,000 to 30,000 head, Dr. Carroll explains that nutrients were overfed 92% of the time, averaging approximately 25 of 28 days per month. However, the magnitude of nutrient deviation varied considerably among farms. These findings reinforce the importance of measuring and evaluating feed and nutrient variation at the individual dairy level rather than assuming every operation experiences the same degree of inconsistency. (08:27 – 10:58)The conversation then examines the relationship between nutrient variation and dairy cow performance. The research linked greater starch deviation with lower dry matter intake but increased milk yield, while crude protein deviation was associated with increased feed intake. Greater NDF deviation was associated with reduced milk yield, and fat deviation was linked with improved pregnancy rate. Dr. Carroll notes that the relationship between crude protein deviation and reproductive performance deserves additional research. (10:59 – 13:19)So, how can dairy farms better monitor feeding consistency? Dr. Carroll recommends using feed weights and loading records to establish benchmarks, with variation below 2% as the goal. Regularly reviewing feeding data and monitoring trends can help producers and nutritionists better understand nutrient deviation and identify where improvements may support more consistent dairy cow performance. (13:20 – 15:23)Importantly, the discussion challenges the idea that all nutrient variation is necessarily negative. Dr. Carroll points to research showing that increases in dietary starch may result in short-term production responses. However, she cautions that the longer-term effects remain less clear, emphasizing the need to consider both immediate and long-term cow responses before adjusting dairy rations. (15:24 – 16:33)Technology may also play a role in improving dairy feed consistency and precision feeding. Dr. Carroll discusses research evaluating a Vector feeding system, which showed modest improvements in variation for dry matter and ADF. The findings suggest that greater automation could help reduce some sources of feed delivery variation and support more precise nutrient management on dairy farms. (16:34 – 20:55)Beyond technology, many opportunities for improving dairy feeding management may already exist in the data farms collect every day. Dr. Carroll encourages producers to review feed records, prepare for weather-related changes in dry matter intake, maintain consistent feed availability, and prioritize employee training. Analyzing existing feeding data can help dairy teams identify patterns and make more informed decisions about ration delivery and management. (20:56 – 23:42)To close the conversation, Dr. Carroll returns to a central theme: nutrient variation does not have to be viewed solely as a problem. While consistency remains an important goal in dairy nutrition, nutrient deviation can also provide an opportunity for producers and nutritionists to examine cow responses, reassess feeding strategies, and better understand what the herd is telling them. Monitoring variation alongside production and reproductive data can provide valuable insight into opportunities for more precise dairy nutrition and feeding management. (23:43 – End)If you enjoyed this episode, subscribe to the Real Science Exchange and share it with your industry colleagues so they can join us at the virtual pub table. Don't forget to register for upcoming Real Science Lecture Series webinars.Want a Real Science Exchange T-shirt? Screenshot your rating, review, or subscription and email it to [email protected], along with your shirt size and mailing address.

The panel features the speakers behind the symposium "Concepts and Strategies to Improve Physiological Resilience to Heat Stress in Dairy Cows": Dr. Yun Jiang (University of Wisconsin-Madison), Dr. Jimena Laporta (University of Wisconsin-Madison), Dr. Vincenzo Lopreiato (University of Messina), and Dr. Maya Zachut (Volcani Institute). The episode begins with introductions. Dr. Jiang describes her research on stress mitigation and dairy nutrition sustainability, and Dr. Laporta shares her path from the University of Florida to UW. Dr. Lopreiato, based in Sicily, notes he has worked on heat stress for three years. (00:00 – 03:48) The discussion turns to heat stress as a global issue. Dr. Zachut explains that cows in Israel are now considered heat stressed eight months a year, and that the topic has become relevant even in northern regions. She stresses that even the most advanced cooling systems cannot fully alleviate heat stress, which is why the symposium brings physiology and nutrition together. (03:49 – 09:19) Dr. Jiang then shares her work on why some cows are naturally more resilient, showing smaller milk drops and less rise in body temperature. Resilient cows produced less methane and had lower inflammation, and she suspects differences in energy metabolism. With 64 cows, she notes the study was too small for genetic analysis. (09:20 – 11:58) Attention then shifts to the dry cow and the "transition calf." Dr. Laporta explains that heat stress in the first 60 to 90 days of life affects the mammary gland, ovary, thymus, and spleen. Cooling pre-weaned calves improved survival and slightly increased milk production later as cows, an opportunity she calls practical for producers facing replacement shortages. (11:59 – 19:37) Dr. Zachut next presents a 2x2 study comparing three versus six cooling sessions per day in mid-lactation cows, with or without beta-caryophyllene, a dietary cannabinoid. More cooling improved welfare, behavior, and milk production, but surprisingly had little effect on immune function after an intramammary LPS challenge. The best cooling plus the supplement showed synergistic effects. (19:38 – 26:10) Dr. Lopreiato then discusses methionine and plant polyphenols, which both activate antioxidant defenses. He notes that even with efficient cooling, milk losses can reach 15%, and he suggests oxidative stress may be a key driver of heat stress damage. (26:11 – 32:18) Particular emphasis is placed on fine-tuning, not suppressing, the immune response. Dr. Zachut calls cooling by far the strongest tool, but cows cooled three times daily with the supplement had resting times similar to cows cooled six times. The panel also discusses capsaicin-containing extracts, which may increase sweating, while Dr. Lopreiato highlights the importance of rumen protection. (32:19 – 38:47) The panel also explores immune function in calves. Dr. Laporta explains that heat stress activates the calf's immune system but makes it less effective, with lower neutrophil function and more illness. Dr. Zachut sees young calves as an opportunity to feed polyphenols before the rumen is fully functional. (38:48 – 43:53) The conversation concludes with key takeaways. Dr. Zachut notes that even the best-cooled farms still see losses in fertility and immune function, while Dr. Jiang asks whether heat-stressed cows have different nutrient requirements. Dr. Laporta emphasizes there is no one solution and that early life matters for building cows resilient to climate change. (43:54 – End) Throughout the episode, the panel reinforces a central message: cooling remains essential, but it is not enough on its own, and pairing good management with targeted nutrition across every life stage offers the greatest opportunity. If you enjoyed this episode, subscribe and share it with your industry colleagues so they can join us at the Real Science Exchange virtual pub table. Don't forget to register for our upcoming Real Science Lecture Series webinars. Finally, if you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription. Then, email a picture to [email protected]. Include your size and mailing address, and we'll mail you a shirt.

The episode opens with introductions. Dr. Santos, who has been at the University of Florida for almost 20 years, explains that Giovanna's undergraduate mentor at the University of São Paulo was his friend from grad school at the University of Arizona. She came to Florida with high recommendations after an externship at the University of Georgia. (00:00 – 03:06) The discussion then shifts to Giovanna's study design. The data set included over 4,000 animals across 11 experiments and 38 treatments. About 21 phenotypic factors, including calving season, parity, dry period length, calf birth body weight, cow body weight, retained placenta and metritis, were first tested in univariable models. Factors with P ≤ 0.20 moved forward, and those with P ≤ 0.10 were kept in the final models for colostrum yield, fat and IgG. (03:07 – 05:01) Giovanna then shares the colostrum yield results. Cows produced more colostrum in fall and summer, multiparous cows produced more, and a longer dry period was positively associated with yield. Surprisingly, dry matter, metabolizable protein and net energy intake had no significant association with colostrum yield, and the slope was actually negative. Cows that produced more colostrum also performed better in the first 10 weeks of the next lactation. (05:02 – 06:52) A key theme of the episode is questioning the common advice to feed more protein before calving when colostrum is poor. Dr. Santos notes that cows eating 800 g of metabolizable protein showed no difference in colostrum yield compared with cows eating 1,400 g. He calls the strong genetic component, with moderate to high heritability, the nicest finding. It suggests cows could potentially be selected for better colostrum yield and composition, possibly as a trait separate from milk yield. (06:53 – 10:11) The conversation also covers the biology behind colostrum IgG. It's still unknown whether colostrum IgG comes only from maternal blood or also from plasma cells in the mammary gland. Giovanna hopes to use RNA sequencing of the placenta to see whether a missing Fc receptor explains why IgG doesn't cross it. She also plans nutritional experiments to see whether specific nutrients change colostrum IgG. (10:12 – 13:01) Next, Giovanna shares her plans to pursue a PhD and likely work in industry in the U.S. Dr. Santos points out research gaps, including limited data on immunoglobulin transporters in the ruminant placenta and how colostrum is made in ruminants. Much of that data currently comes from laboratory animals. (13:02 – End) Please subscribe and share this episode with your industry colleagues and invite them to join us at the Real Science Exchange virtual pub table. Be sure to register for upcoming Real Science Lecture Series webinars to continue the conversation. Finally, if you'd like a Real Science Exchange t-shirt, screenshot your rating, review, or subscription and email it to [email protected] with your size and mailing address, and we'll send one your way.