In this episode, we showcase student research at the 2025 ADSA Annual Meeting in Louisville, Kentucky. Abstracts can be found here: ADSA 2025 Annual Meeting

Abstract 2186: Effects of feeding alternative forage silages on early lactation performance and gas production in multiparous Holstein cows. (00:15)

Guests: Barbara Dittrich and Dr. Heather White, University of Wisconsin-Madison

Co-Host: Dr. Clay Zimmerman, Balchem

Barbara substituted rye silage, triticale silage, rye-camelina-hairy vetch silage, and triticale-camalina-hairy vetch silage to replace 10% of the alfalfa silage in the control diet for her experimental diets. Dry matter intake and gas production were similar across diets. Average milk yield was higher in the rye mix silage group compared to the triticale mix silage group, but no treatment was different than the control.  

Abstract 1602: Optimizing starch concentrations in low-forage diets. (11:22)

Guests: Irie Moussiaux and Dr. Kirby Krogstad, Ohio State University

Co-host: Dr. Jeff Elliott, Balchem

Irie investigated different levels of starch in a low-forage diet (12.5% NDF) by replacing soybean hulls with corn to yield 20%, 25%, or 30% starch. Dry matter intake and milk production were the same for all three starch concentrations; however, the low starch diet had the highest milk fat yield and energy-corrected milk yield. 

Abstract 2183: Effects of partial replacement of corn and oat silages with extracted stevia plant on production, behavior, and digestibility in dairy cows. (17:05)

Guests: Mariana Marino and Dr. Jose Santos, University of Florida

Co-host: Dr. Clay Zimmerman, Balchem

Mariana fed stevia plant byproduct as a replacement for corn and oat silage in lactating cow diets. All diets had 40% grain and 60% forage. Stevia byproduct was included at 0, 25%, or 40% of diet dry matter. The byproduct is of very fine particle size and is relatively high in lignin. This resulted in higher dry matter intake, but lower milk production for the highest stevia diet. 

Abstract 2472: Evaluating feed sorting behavior and TMR composition in roughage intake control feeding systems. (26:38)

Guests: Sophia Green and Dr. Heather White, University of Wisconsin-Madison

Co-host: Dr. Ryan Pralle, Balchem

Sophia evaluated feed sorting in a research intake control feeding system (RIC bins). Feed sorting primarily occurred in the last 12 hours of the feed day, and particle size was smaller at the end of the day than earlier. Compared to fresh feed at hour zero, the chemical composition of the diet did not change throughout the feed day. RIC bins did not introduce additional variance in nutrient consumption. 

Abstract 1603: Assessing an ex vivo assay with gastrointestinal tissue sections to investigate mucosal immune responses in dairy calves. (35:24)

Guests: Paiton McDonald and Dr. Barry Bradford, Michigan State University

Paiton challenged explants from the ileum and mid-jejunum in the lab with rotavirus or E. coli compared to a control. Pathogen stimulation increased mRNA abundance of TNF and IL6 above control. Ileal sections secreted more cytokines than jejunal sections. 

Abstract 1466: The short-term effect of increasing doses of palmitic and stearic acid on plasma fatty acid concentration and mammary arteriovenous difference in Holstein cows. (40:17)

Guests: Alanna Staffin and Dr. Kevin Harvatine, Penn State University

Co-host: Dr. Jeff Elliott, Balchem

Alanna fed mid-lactation cows 0, 150, 300, 500, or 750 grams of palmitic acid, stearic acid, or no supplement control. Palmitic acid increased milk fat yield at lower doses compared to stearic acid. Alanna found that the mammary gland increases its arteriovenous (AV) difference and uptake of palmitic acid when higher concentrations are provided, but AV difference and uptake of stearic acid did not change. 

Abstract 2006: Does hay improve performance in pair-housed dairy calves? (50:00)

Guests: Gillian Plaugher and Dr. Melissa Cantor, Penn State University

Gillian fed pelleted hay to pair-housed dairy calves along with milk replacer and calf starter. Control calves received milk replacer and calf starter only. Hay-fed pairs grew faster than controls after day 21 and were heavier at day 70. Hay feeding did not impact calf starter DMI or feed efficiency. 

Abstract 1463: Dietary metabolizable protein and palmitic and oleic acids affect milk production in early lactation dairy cows. (1:02:03)

Guests: Jair Parales-Giron and Dr. Adam Lock, Michigan State University

Co-host: Dr. Clay Zimmerman

Jair fed two different levels of metabolizable protein and 3 different levels of supplemental fatty acids from 1 to 22 days in milk followed by a common diet to evaluate carryover effects to day 50. Metabolizable protein and fatty acid supplementation had additive effects on milk production. Cows fed the highest dose of both metabolizable protein and fatty acids produced 8.9 kg more energy-corrected milk per day compared to the low metabolizable protein diet without fatty acid supplementation.

This episode features speakers from the 2025 ADSA Opening Session Panel: Designing Dairy 2045—Envisioning the Future of Cows, Dairy Products, and Farms, which explored the long-term future of dairy.

Dr. VandeHaar explains the idea behind creating the panel discussion for the opening session and his selection of the other three podcast guests as panel members. (2:02)

Dr. Baes was the genomics expert on the panel. Her talk focused on what types of data have been collected on dairy cattle in the past and in the future, as well as the collaboration needed among different disciplines to ensure the right information is being collected in the appropriate way. (4:54)

Dr. Hostens was the data analytics expert on the panel. He is a veterinarian by training, but has a strong interest and passion around big data. He notes that a “gut feeling is good, but data is better.” He talks about a project where an existing language model was trained with all Journal of Dairy Science abstracts since 1917 so that answers from chatbots would be fed by JDS knowledge. He talks about other ways this type of approach could be used in the future to provide answers to questions on-farm. (8:09)

Eve is the Senior Vice President of Strategic Intelligence at DMI and was the food futurist expert on the panel. She notes that dairy’s image is shifting to that of a health and wellness food. The question then becomes what is the future of health and wellness, and what does the dairy industry need to do to build towards that future? She talks about the roles of data and artificial intelligence in enabling us to design the foods of the future tailored to each individual. She advises that knowing more about your product than anyone else on the planet through technology and science allows you to anticipate what consumers are going to want and need in the future.   (14:33)

The panel talks about genetic selection to produce particular components “naturally” rather than through food processing, where the industry is headed in regard to total milk production, breeding dairy cows for health, providing tools for making wise use of resources especially in developing countries, and how the future of big data could impact decisions made on-farm. (20:12)

Eve talks about the consumer who has (processed) collagen in their coffee each morning but also demands clean, whole foods. Consumers want it all. She envisions a future where consumers will know the truth about how foods work in their body because they’ll have the technology to measure it. The group goes on to talk about wearable technology like continuous glucose monitors and the variability that exists in the human population compared to variation in Holstein cows, for example. (35:05)

The guests talk about where the gaps are in technology - what else do we need to take the next step? Dry matter intake might be one, but Dr. Baes notes that the Danish have technology through video of the feed bunk that allows them to predict intake with surprisingly high accuracy. (41:59)

Panelists share their take-home thoughts. (47:07)

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In the Real Science Exchange Legacy Series, we celebrate the pioneers who have shaped the dairy industry. In this episode, we honor Dr. Bill Weiss, professor emeritus at The Ohio State University. This episode was recorded at the 2025 ADSA annual meeting in Louisville, Kentucky, where Dr. Weiss received the 2025 ADSA Award of Honor. 

Dr. Weiss shares about his early life, schooling, and academic career. (2:29)

Panelists introduce themselves and how they know Bill. Dr. Firkins started at OSU one month before Dr. Weiss, Dr. St. Pierre was in graduate school with Dr. Weiss, and Dr. Tebbe was Dr. Weiss’s last graduate student. (4:47)

Dr. St. Pierre and Dr. Firkins share about Bill’s deep contributions to the science of energy, protein, and trace mineral nutrition in dairy cattle. They note he was a great mentor to his students and an exceptional colleague. Dr. Weiss reflects on his career and the collaborations he had with his colleagues even though they were on different campuses. Dr. Tebbe underlines what a hard worker Dr. Weiss is, yet always had time for his students. (11:45)

Panelists share stories about Bill’s driving, winning 20 gallons of ice cream in a contest in graduate school, Bill’s less serious side, and his love for cars and golf. They also tease him a bit for being a glutton for punishment and serving on both the 2001 NRC and NASEM committees. (19:06)

Panelists share their take-home thoughts. (29:11)

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This episode features speakers from the 2025 ADSA Applied Nutrition Symposium, “Milk Pricing Dynamics and Strategies for Enhancing Milk Fat Production.” 

Dr. Lock gave the highlights of his presentation on dietary opportunities for promoting milk fat.  (2:18)

Dr. St. Pierre’s presentation focused on the change we've had in the way milk and its components are priced. (5:25)

Dr. Van Amburgh’s symposium talk covered amino acid supplementation to high producing cows eliciting more of a milk fat response than a milk protein response. (9:31)

Dr. Van Amburgh and Dr. Lock talk about where butyrate fits into milk fat synthesis. Dr. Van Amburgh shares some of his experiences with grass-based dairy diets in Ireland and how those might influence milk fat production. The group discusses de novo and preformed fat synthesis and how diets may or may not influence those two mechanisms. (12:16)

The guests talk about an abstract from Dr. Van Amburgh’s lab at the ADSA meetings about supplemental lysine levels. This leads into a discussion of lactose production and fluid milk volume, as well as feedback from cheese processors and the impact of supplemental chromium on milk production parameters. (22:31)

Dr. St. Pierre talks about cheese processor concerns with increased milk fat concentrations, milk pricing structures, and milk perishability. (28:27)

The panel discusses metabolizable protein, essential, non-essential, and branched-chain amino acids, and how the view of fatty acids and amino acids has changed from simple substrates to make milk components to compounds with biogenic activities. (36:20)

Dr. St. Pierre talks about the inaugural Industry Day at the 2025 ADSA meetings and goals for similar future events. (43:01)

Panelists share their take-home thoughts. (48:13)

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In this episode, we feature some of the winners of poster and oral presentation competitions at the 2025 ADSA Annual Meeting in Louisville, Kentucky. Abstracts can be found here: ADSA 2025 Annual Meeting

MS Oral Presentation, Production

Guests: Trinidad Fernandez-Wallace and Dr. Lautaro Rostoll-Cangiano, University of Wisconsin-Madison

Co-host: Dr. Laura Niehues, Balchem

Abstract 1218: Immunity at the crossroads of cellular metabolism: Navigating T helper shifts in the periparturient period of dairy cows. (0:08)

Trinidad found that T-helper cell metabolism and proliferation were both upregulated after calving, which may impact the effectiveness of immune responses during the transition period. The group discusses if T-helper cells could be used as a marker of inflammation in the future and how Trinidad’s results may have been different if samples had been collected between 3 and 28 days after calving.

PhD Oral Presentation, Production

Guests: Natnicha Taechachokevivat and Dr. Rafael Neves, Purdue University

Co-host: Dr. Sion Richards, Balchem 

Abstract 1107: Relationships between systemic inflammation, subclinical hypocalcemia, and hyperketonemia in clinically healthy Holstein cows. (8:07)

Natnicha investigated the association of plasma haptoglobin (an inflammatory marker) on days 1 and 3 in milk with subclinical hypocalcemia and hyperketonemia. Systemic inflammation appears to be associated with subclinical hypocalcemia and hyperketonemia and reduced milk yield in multiparous cows. When multiparous cows exhibited both inflammation and metabolic disease indicators, they produced less milk; however, when primiparous cows exhibited both inflammation and metabolic disease indicators, they produced more milk. 

3 Minute Thesis

Guests: Savitha Saikumar and Dr. Diwaker Vyas, University of Florida

Co-host: Dr. Laura Niehues, Balchem

Abstract 1548: Effects of peripartal supplementation of prototype postbiotics on intake, rumen fermentation, colostrum quality, and performance in transition dairy cows. (15:14)

Savitha investigated the effects of a prototype postbiotic supplement in transition cows from 35 days before calving to 63 days after calving. Cows on the postbiotic treatment received 25 grams per day topdressed on their TMR. Before calving, the postbiotic had no effect on dry matter intake, body condition sore, body weight, or total VFAs. After calving, the postbiotic increased dry matter intake and milk yield after 6 weeks, and increased energy-corrected milk and fat-corrected milk with no effect on body weight, body condition score, or rumen fermentation profile.

PhD Poster 

Guest: Amanda Fischer-Tlustos, University of Guelph Abstract 2012: Characterization of dry-period mammary acetate and glucose metabolism and their association with colostrum production in multiparous Holstein cattle. (25:15)

Amanda’s research evaluated acetate and glucose metabolism in the mammary gland during the dry and calving periods to better understand how colostrum is made. Acetate uptake by the udder remained fairly constant until one week before calving, when it started to increase. Glucose uptake did not increase until the onset of calving. Previous lactation milk production and far-off mammary metabolism were both negatively correlated with colostrum production. Amanda hypothesizes that high producing cows who have trouble drying off may have high amounts of metabolic activity in the mammary gland when they should have low activity, which may result in lower colostrum production at the subsequent calving. 

PhD Oral Presentation, Southern Branch Division

Guests: Bridger Sparks and Dr. Clarissa Strieder-Barboza, Texas Tech University

Co-host: Dr. Ryan Pralle, Balchem

Abstract 1215: Adipose tissue neuro-like cell profile changes with ketosis in dairy cows. (33:05)

Bridger investigated neuro-like cells in the adipose tissue of cows with or without subclinical ketosis. The transcriptional profile of neuro-like cells changed when collected from cows with subclinical ketosis, which may indicate a potential regulatory role in adipose tissue metabolism. Perhaps modulation of neuro-like cells could potentially alleviate excessive adipose mobilization in the postpartum period. 

ADSA Graduate Student Division Highlights

Guests: Evelyn Yufeng Lin, North Carolina State University; Miranda Farricker, Cornell University; Conor McCabe, University of California-Davis; Dr. Maurice Eastridge, Ohio State University. (40:45) 

Dr. Eastridge is the chair of the ADSA Foundation and explains some of the Foundation’s current projects. Evelyn and Conor are past presidents of the ADSA Graduate Student Division, and Miranda is the incoming president. Each student gives a bit of background on themselves and their research and describes what the Graduate Student Division does and how they foster new graduate students in ADSA.  

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Dr. Dahl presented a Real Science webinar on heat stress on April 1, 2025. You can find the webinar at balchem.com/realscience. This episode of Real Science Exchange further explores the key elements of Dr. Dahl’s webinar.

Dr. Dahl talks about geographical differences in whether farms provide cooling for dry or lactating cows. Cows get heat stressed long before humans. Some farms are concerned that using misters for cooling will add too much water to their manure handling systems. He notes a study comparing conventional misters and fans, no cooling, and smart soakers that only provide mist if a cow is present. When the total amount of water (drinking + cooling system) was evaluated, the smart soakers cooled as well as the conventional system, but used the same amount of water as the no cooling group.  (7:08)

During the dry period, a main impact of heat stress is a reduction in dry matter intake. However, there are dramatic shifts in immune function and effects on mammary development and redevelopment in cows who experience heat stress in the dry period. This sets the stage for lower productivity in the next lactation. In addition, there are many negative impacts on the in utero calf from heat stress. Calves from heat stressed dams are challenged from a growth standpoint, in addition to organ development challenges in the mammary gland, ovaries, and immune system. These calves are less likely to make it through their first lactation, are less productive, and pass their poor production and survival phenotype on to their offspring. (14:28)

Dr. Tao talks about when during the dry period to provide cooling for cows. Spoiler alert: the entire dry period! He also notes that bred heifers should have cooling provided for the last 60 days of gestation as well. Laura asks about the impact of heat stress on neonatal calves and how it may impact their mammary development. More research is needed in this area, and you also have to wait two years to collect data from the first lactation. Dr. Dahl notes that observations from season of birth data indicate lower longevity for calves who are born to heat stressed dams. (18:26)

Milk production is decreased by 8-10 pounds per day for cows stressed during the dry period, and they also produce a lower volume of colostrum. Calves from heat stressed dams also have a lower rate of passive transfer of antibodies from colostrum. The panel talks about why that might be, whether or not those gut differences persist after calfhood, and how that might be related to growth differences between heat stressed and cooled calves. (27:30)

What about reproduction? It appears that heat stress during the dry period has a negative impact on reproductive function in the subsequent breeding season. Recent research has indicated that calves experiencing heat stress in utero have poor gonadal development and lower follicular reserves. In addition, placental development is also negatively affected. Dr. Tao notes that heat stress negatively impacts mammary gland involution during the dry off period. All of this leads to a decrease in cow longevity. (35:36)

Dr. Dahl describes a retrospective records study using Florida and California herds to evaluate cows in their fifth through eighth lactations. In Florida, about three-quarters of those animals were born in cooler parts of the year rather than in hotter months of the year. The pattern in California was similar, though not quite as extreme. (44:02)

Dr. Tao and Dr. Dahl expand on the economics of cooling cows, including return on investment and the costs of not cooling. The guests also talk about some of their research abstracts at the 2025 ADSA meetings. (48:10)

Panelists share their take-home thoughts. (57:41)

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This episode was recorded in Fort Wayne, Indiana, during the 2025 Tri-State Dairy Conference.

Dr. Fessenden gives an overview of his presentation which covered both research and field information on automated milking systems. He recommends going back to basics and formulating a rumen-friendly PMR with a complementary palatable feed that encourages the cows into the robot system. (5:57)

The panel discusses ideas for driving cows to the robot on different types of PMRs, management of transition and late lactation cows in automated milking systems, and the use of custom pellets versus other supplemental feeds in the robot. (9:04)

Dr. Fessenden talks about some of his experiences visiting automated milking systems in Europe and some of the differences between European and North American approaches to diet formulations in automated systems. The group goes on to talk about different options for supplemental feed formulations in the robot. (18:38)

Dr. Fessenden and Dr. Tylutki share ideas for how feeding technology could help both traditional and automated milking farms in the future. They discuss more precise grouping of cows and targeted feeding of those groups to better match requirements, as well as how movement to different pens and diet changes can impact milk production. (23:45) 

Dr. Tylutki updates the group on advancements in the AMTS balancing tools for multiple robot feeds. He and Dr. Fessenden describe the challenges of developing new tools that are streamlined and user-friendly for nutritionists. They also delve into the role artificial intelligence and machine learning might play in ration balancing in the future. (29:32)

Dr. Fessenden encourages nutritionists to think outside the box when working with automated milking herds to make decisions that are right for that particular farm. Dr. Tylutki chimes in with advice to spend time actually watching the cows on the farm, and Dr. Van Soest echoes this sentiment when it comes to troubleshooting issues with the robots themselves. Don’t just assume it’s an issue with the ration - ask or observe for yourself what may have changed on the farm that could contribute to the issue the farm is facing. (40:02)

Panelists share their take-home thoughts. (45:20)

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This episode was recorded in Fort Wayne, Indiana, during the 2025 Tri-State Dairy Conference.

Dr. Schwanke begins by describing how we can shape cattle personalities through handling and management and adapting our strategies to accommodate different personality traits so as to not cause undue stress. Personality traits are consistent across time and context, which is nuanced by the other animals in a particular group. There are five generally recognized personality traits: boldness, exploration, activity, sociability and aggressiveness. Some debate exists as to whether dominance should be considered a sixth trait or if it’s just an outcome of the other five. (5:43)

Dr. Schwanke’s research focused mainly on how cows react to specific stressors, such as adapting to an automated milking system. In a robotic system, cows who are more independent, explorative and bold are more likely to do well. Some diversity is good because it can help to minimize long-term antagonistic interactions in a group. If we have cows that are very similar to each other, it will take longer for them to establish a social hierarchy.  (10:05)

The panel discusses where the research is in regard to on-farm applicability and potential genetic components of personality traits. In the future, Dr. Schwanke envisions automated assessments of cow personality through computer vision cameras in the barn, fed into an algorithm that creates a personality ranking of cows based on their behaviors. She also notes personality traits can help predict a cow’s coping style: proactive, reactive and intermediate. Proactive cows are more bold, explorative and aggressive. They thrive in predictable, stable conditions. Reactive cows are more fearful, less active and less dominant. They typically do better than proactive cows in unpredictable or changing environments because they’re better able to modify their behavior to the environment they find themselves in. (14:09)

The panel talks about future research goals in this area, including transition to automated milking systems, modifying feed management for behavioral and nutritional requirements and impacts of commingling stress. The guests also explore behavioral research in calves and brainstorm about future research with this age group, as well as talk about potential implications of making the wrong selection decisions for personality traits. (20:08)

Are there things dairy producers could do to condition calves to be more adaptable to an automated milking system later in life? If a calf is reared in an automated feeding system, do they adapt to an automated milking system more easily? We don’t have the research yet to answer these questions, but they’re great questions. The panel also talks about how to scale up personality trait information to large herds, how precision feeding systems and personality traits might interact and how machine learning and computer vision technology can automate personality trait assessments. (28:46)

Panelists share their take-home thoughts. (35:02)

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This episode was recorded in Reno, Nevada, during the 2025 Western Dairy Management Conference.

Dr. Hutjens’ presentation focused on herds producing seven pounds of milk fat and milk protein per cow per day, and the genetics, on-farm management and nutrition to make that happen. The panel discusses where components could top out, how added dietary fat has influenced components and the importance of high quality forage to de novo fat synthesis. (4:09)

The panel explores how well nutritionists are keeping up with rapid genetic change in milk component production and how farmers respond to recommendations for things like rumen-protected fatty acids and supplemental fat. Dr. Nelson shares some of the unique challenges and opportunities faced by the California dairy producers he works with. (11:56)

Dr. Hutjens gives some benchmark values for energy and protein efficiency. The panel debates the merit of energy-corrected milk per stall as an efficiency measure, with the consensus being it might lead to crowding, which would then probably decrease milk and component production due to decreasing cow comfort. The group also discusses selecting for feed efficiency and the heritability of feed efficiency. (16:33)

The panel dives into the topic of feed ingredients. High-oleic soybeans and high quality forages are a focus in some parts of the country. Dr. Nelson discusses non-forage fiber sources available in the California market, such as citrus, plums, apples and carrots. The group talks more about how high-sugar byproducts influence rumen fermentation, which is different from starch, as well as benefits in palatability, digestibility and intake. (21:03)

Dr. Hutjens talks about benchmarks for milk components and different strategies for increasing component production. Rumen-protected amino acids, purchased fats, roasted high-oleic soybeans and urea are discussed. The group also talks about what might happen if milk processors start asking for less milk fat, for example. Dr. Hutjens talks about how nutritionists can help balance rations to yield different results for different markets. (33:04)

Panelists share their take-home thoughts. (40:33)

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This episode was recorded in Fort Wayne, Indiana, during the 2025 Tri-State Dairy Conference.

Dr. Firkins’ presentation covers key aspects of how to improve digestibility of different diet components: fiber, starch, fat and total diet. (4:31)

The negative relationship between starch in the diet and fiber digestion has been well known for more than 50 years. A recent meta-analysis showed the depression in fiber digestibility starts at very low starch concentrations. Dr. Weiss points out this can’t be due to low rumen pH at that starch level. Dr. Firkins agrees pH is probably only about half of the relationship and the other half is factors called the carbohydrate effect. He goes on to say adequate ammonia and amino acids are necessary for the fibrolytic bacteria in the rumen to maximize fiber digestibility, and urea alone is not adequate. The panel agrees there is little knowledge about what exactly the amino acid requirements of fibrolytic bacteria are or should be. (6:05)

Dr. Firkins shares some of his findings regarding how sugars impact fiber digestibility. Dr. Krogstad notes grain particle size can have key impacts on fiber digestibility and the panel discusses some of the challenges in nailing down optimal particle size. (13:39)

Dr. Weiss indicates diets should be formulated  for rumen degradable starch - but how do we get that number? Dr. Firkins explains some of the difficulty in making accurate, cohesive predictions. The panel discusses some field measures that may be helpful. (18:24)

Ruminants have lower fat digestibility than monogastrics. The panel explores biological factors that might be limiting fat digestibility. Dr. Firkins believes palmitic and oleic acids probably help the microbes and that is why we see improved diet digestibility when those fatty acids are supplemented. He encourages further exploration into the reason behind this and the mechanism by which it occurs. Dr. Krogstad mentions a Utah State study that also saw improved diet digestibility and also evaluated microbial fractions and phospholipids. (22:44)

The panel explores the relationship between rumen-degradable protein and fiber digestibility. What happens when RDP is too high or too low? What is the optimal level of RDP to maximize digestibility? How does the composition of the base diet influence how much RDP you might need? What role do peptides play in the rumen? (29:00)

Panelists share their take-home thoughts. (41:52)

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