Real Science Exchange

• The Impacts of Heat Stress on the Dry Cow and Her Fetus with Dr. Jimena Laporta, University of Wisconsin-Madison, and Dr. Brian Gerloff, Renaissance Nutrition, Inc

  This episode was recorded in Fort Wayne, Indiana, during the 2025 Tri-State Dairy Conference. Dr. Laporta gives an overview of her presentation, focusing on the impact of heat stress during the dry period on the cow, her daughters and her granddaughters. She covers heat stress impacts on mammary gland involution, as well as fetal programming effects on the daughter and granddaughter. (3:37)Daughters of heat-stressed cows have fewer sweat glands located deeper in the skin, thicker skin and more sebaceous glands. This was observed at birth, weaning and puberty. They sweat more than heifers who weren’t heat stressed in utero, but have higher rectal temperatures during the preweaning phase. Dr. Laporta hypothesizes that if those calves were exposed to additional stress, they would be more susceptible to illness because of the higher core temperature.  (6:34)The panel discusses heat stress impacts on male fetuses and the potential for epigenetic changes to be transmitted through semen. Dr. Gerloff asks about differences in the impacts of heat stress on first-calf heifers compared to older cows. Dr. Laporta describes the survival rates of heifers who were heat-stressed in utero. Heifers are lost from the herd even before first calving, with more following in first and second lactation.  (11:00)Dr. Laporta outlines the differences between heat-stressed and cooled treatments in her experiments. They measure respiration rates and rectal temperatures to assess the physiological impacts of heat stress in the cows. Scott asks how long the heat stress period needs to be in order to observe negative effects. Dr. Gerloff asks about calf mortality rates between the two groups. Dr. Laporta estimates a 12% death loss in the heat stress groups, who seem to be more susceptible to the usual calf illnesses. It appears that gut closure might occur earlier in heat-stressed calves - maybe even before birth, which does not bode well for their immune systems. (16:49)Dr. Laporta details how heat stress impacts mammary gland involution. Early in the dry period, you want a spike in cell death to build new cells for the next lactation. In heat-stressed cows, the spike in cell death early in the dry period is diminished, not allowing those cells to die. This results in less proliferation of the mammary gland, and the cow starts her next lactation with older cells that weren’t renewed in full. Thus, producing less milk. Dr. Gerloff shares some of his experiences with heat stress in his area of Illinois. (22:17)Heat stress has negative impacts on other organs as well. Heifers who experienced heat stress in utero are born with larger adrenal glands with altered microstructure. Dr. Laporta describes some of the DNA methylation that has been observed in these heifers. The panel discusses whether the response would be similar for other types of stressors, like cold stress or social stress. (26:19)What can we do to mitigate these impacts? Cooling dry cows so they can thermoregulate during gestation is critical. Altering diets to account for heat stress is also an important strategy. Unfortunately, there is no magic bullet to “fix” cows who were exposed to heat stress in utero, but these negative implications can be prevented. Dr. Laporta has also focused on what she calls perinatal programming - after the calf is born, what can we do? She has been working to develop cooling mechanisms for calves and is interested in further investigating early life mammary development. (33:41)When a dry cow experiences heat stress, she has fewer and smaller alveoli. Daughters of those cows have smaller udders with altered tissue growth. Granddaughters of those cows have fewer estrogen receptors in their udders and negative impacts on mammary proliferation. (44:30)Panelists share their take-home thoughts. (47:52)Scott invites the audience to Bourbon and Brainiacs at ADSA in Louisville - a bourbon tasting with all your favorite professors! Sign up here: https://balchem.com/anh/bourbon/ (54:31)Please subscribe and share with your industry friends to invite more people to join us at the Real Science Exchange virtual pub table.  If you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to anh.marketing@balchem.com. Include your size and mailing address, and we’ll mail you a shirt.

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• From the Cow’s Perspective: Two Decades of Management at Miner with Dr. Rick Grant, Trustee, William H. Miner Agricultural Institute; Dr. Bill Weiss, Professor Emeritus, Ohio State University; Dr. Neil Michael, Progressive Dairy Solutions

  This episode was recorded in Fort Wayne, Indiana, during the 2025 Tri-State Dairy Conference. Dr. Grant gives an overview of his presentation at the conference, highlighting cow time budgets and the importance of natural cow behavior to health, welfare and productivity. The impacts of overcrowding, including rumen pH and de novo fatty acid synthesis, are a key component of his message. (7:07)Eating, resting and ruminating are the big three behaviors we’ve studied for decades. In addition to their obvious importance to cow welfare, they have a real health and performance effect. Dr. Grant suggests the recumbent rumination - just lying down and chewing her cud - is really the cow’s superpower. Cows with the same rumination time who accomplish more while lying down have less subacute ruminal acidosis, greater dry matter intake, and higher fat and protein content in their milk. It all boils down to the balance between eating time and recumbent rumination time. (12:15)The panel discusses the definition of overcrowding. Spoiler alert: it depends. (15:50)Clay asks Rick if overcrowding of beds or feed bunks is more important. The easy answer is both, but Rick acknowledges he’d say beds if he were pushed for an answer. Resting is a yes or no; she’s either lying down or she’s not. From the feed bunk perspective, a cow can alter her behavior to a point for adjusting to overcrowding - eat faster, change her meal patterns, etc. A hungry cow will walk by the feed to recoup lost rest time. Cows should be comfortable enough to spend at least 90% of their rumination time lying down. (17:50)Dr. Grant thinks of overcrowding as a subclinical stressor. A cow has different “accounts” for different activities: lactation, health, reproduction, etc., as well as a reserve account. To combat the subclinical stress of overcrowding, a cow uses her reserve account, but that’s hard to measure. If the reserve account gets depleted and another stressor comes along, the overcrowded pens are going to show greater impacts. The panel brainstormed ideas for how to better measure a cow’s reserve account. (19:39)Clays asks if overcrowding is affecting culling rates. The panel assumes it has to be, though no one can point to a study. Dr. Grant notes there is data from France that shows decreased longevity in cows who don’t get enough rest, which is a hallmark of overcrowding. Given the low heifer inventory, the panel muses if the industry ought to pay more attention to the culling impacts of overcrowding and have a more dynamic approach to evaluating stocking density as market and farm conditions shift. (25:10)Bill asks about nutritional and management strategies to reduce the stress of overcrowding. Rick notes that overcrowding tends to make the rumen a bit more touchy, so he talks about formulating diets with appropriate amounts of physically effective fiber, undigested NDF, rumen-fermentable starch, and particle size. (29:21)Dr. Grant talks about the differences in rumination when a cow is lying down versus standing. The panel discusses cow comfort, preferred stalls, and first-calf heifer behavior in mixed-age groups with and without overcrowding. Bill and Rick agree that having a separate pen for first-calf heifers on overcrowded farms would benefit those heifers. Dr. Michael comments on evaluating air flow and venting on-farm. (33:49)The panel wraps up the episode with their take-home thoughts. (47:55)Scott invites the audience to Bourbon and Brainiacs at ADSA in Louisville - a bourbon tasting with all your favorite professors! Sign up here: https://balchem.com/anh/bourbon/ (52:02)The paper referenced in this conversation from Dr. Bach can be found here: https://www.sciencedirect.com/science/article/pii/S0022030208711226Please subscribe and share with your industry friends to invite more people to join us at the Real Science Exchange virtual pub table.  If you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to anh.marketing@balchem.com. Include your size and mailing address, and we’ll mail you a shirt.

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• Don’t Let Overcrowding Stress Wreck the Response to Your Ration with Dr. Jim Tully, Targeted Dairy Nutrition LLC; Dr. Tom Overton, Cornell University; Jason Brixey, J-Heart

  This episode was recorded in Reno, Nevada, during the 2025 Western Dairy Management Conference. The panel is reviewing a presentation given by Dr. Rick Grant, who was unable to be on the podcast. The presentation was based on the idea that crowding is a subclinical presence. If you manage it with people and resources, a dairy can do very well. But if something happens in that crowded situation, like a disease or heat stress, it can tip performance over the edge. Evaluating time budgets for cows can allow for the identification of places to improve. Beds are vitally important. If a cow doesn’t have a bed due to crowding then she’s not lying down, chewing her cud, which is what allows her to be as efficient as possible. (3:19)Jason thinks about time budgets as a tool for managing stress. Jim agrees and notes that crowding is part of every cow’s day, but we can manage to minimize that time in most instances. Jason and Jim talk about some of their approaches to evaluating crowding when they work with a dairy, and where pain points are often located. (5:57)Jason liked Dr. Grant’s takeaway message that the cow doesn’t necessarily care she’s overcrowded as long as she has a bed she doesn’t have to fight for and room at the feed bunk she doesn’t have to fight for. He describes a very successful client who is overcrowded, but everything else is managed well. All other stressors have been removed, so the only stressor remaining is the overcrowding. But when additional stressors compound crowding, then dairies experience issues. He adds there is a huge opportunity for error when feeding to slick bunks in an overcrowding situation. (16:15)Jim talks about different measures of efficiency. Is it milk per cow, milk per free stall, milk per parlor stall, or milk per pen? He thinks the real answer is “it depends,” and the answer might be different for each dairy. Jason notes that the bank wants to see assets on a balance sheet, and the cows are the assets. (19:24)The group discusses geographical differences in overcrowding. Jim’s observations show crowding increases as one moves east in the US. Tom agrees and notes 20-30% of the available stalls are in his part of the world. Overcrowded cows eat faster, and this impacts rumen efficiency, probably leading to lower de novo fatty acid synthesis and overall lower components. The panel talks about whether or not there is such a thing as an “overcrowding ration.”(20:59)The panel relays some real-world examples of crowding where dairies would cull cows to decrease milk production, but production would remain the same because the cows were now less crowded. They talk more about other management strategies that need to be on point if a dairy is going to overcrowd. (27:50)The panel wraps up with their take-home thoughts for dairy producers and nutritionists. Jim and Jason share their contact information with the audience. (38:20)Scott invites the audience to Bourbon and Brainiacs at ADSA in Louisville - a bourbon tasting with all your favorite professors! Sign up here: https://balchem.com/anh/bourbon/ (45:02)The paper referenced in this conversation from Dr. Bach can be found here: https://www.sciencedirect.com/science/article/pii/S0022030208711226Please subscribe and share with your industry friends to invite more people to join us at the Real Science Exchange virtual pub table.  If you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to anh.marketing@balchem.com. Include your size and mailing address, and we’ll mail you a shirt

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• The Shift to Feed Efficiency-Based Herd Management: Driving Profitability with Advanced Data with Dr. Veronica Shabtai, Afimilk; Emily Starceski, ADK Dairy; Shane St. Cyr, ADK Dairy; Walt Cooley, Progressive Dairy Publishing

  This episode was recorded in Reno, Nevada for the 2025 Western Dairy Management Conference. Dr. Shabtai gives an overview of her presentation. Afimilk has a new technology that includes a feed efficiency sensor to determine eating, rumination, heat stress monitoring and more. The Feed Efficiency Service combined with the AfiCollar can estimate dry matter intake, which, when combined with Afimilk’s milk meter data, yields an efficiency value of milk income over feed cost for each cow. She details how the algorithm works to predict intake and some of the challenges faced during the development of this technology. The algorithm was developed with Holsteins, but a Jersey algorithm is nearing completion. (5:33)Shane and Emily share some of their experiences with beta-testing the Feed Efficiency technology on-farm to evaluate, including animal-to-animal variation and variation in different stages of lactation. The panel discusses how genomics could pair with this data to aid in selection decisions. (9:21)Walt asks Dr. Shabtai to share how the company took the technology from research facilities to commercial farms, and asks Shane and Emily to share how the technology has proven itself on-farm. (13:11)Shane notes that they’ve had a handle on the milk side of the efficiency equation of individual cows for a while, but they didn’t know much about the feed intake side of the equation. This technology allows for that. Shane also shares how this technology adds another tool to their dairy’s sustainability toolbox.  (18:50)Walt asks both producers to share a metric that they thought was important before, but now that we have more knowledge and technology, it might not be as important as they thought. Shane’s pick is starch level in corn silage, and Emily’s is percent pregnant by 150 days in milk. (21:18)Dr. Shabtai shares the basics that a producer would need to implement this technology. She details a few things that have changed and will change about the product based on data from beta testing and notes there are always new things to see and find on-farm. (22:59)Scott asks Shane and Emily what metric they’d like to measure that they can’t measure yet. Shane wonders if there would be a way for AI to compile weather and market data to assist with milk or feedstuff contracting decisions. Emily would like to be able to use more on-farm technology to help manage people. She shares how the data she has now allows her to see different improvements that could be implemented for different milking shifts. Shane talks about need-to-know information versus neat-to-know information. (26:35)The panel discusses how the technology is updated through software rather than hardware when new versions are available. They also share some tips for implementing the software on-farm. Walt asks each panelist their “I wonder if…” question. (29:58)The panel wraps up with their take-home thoughts, and Dr. Shabtai shares where farmers can learn more about Afimilk’s feed efficiency technology by visiting afimilk.com. (36:49)Please subscribe and share with your industry friends to invite more people to join us at the Real Science Exchange virtual pub table.  If you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to anh.marketing@balchem.com. Include your size and mailing address, and we’ll mail you a shirt.

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  41:28
• Mining the Liquid Gold: Strategies to Supercharge Colostrum Production with Dr. Sabine Mann, Cornell University; Dr. Don Niles, Dairy Dreams LLC; Joey Airosa, Airosa Dairy Farms; Dr. Will Mustas, Progressive Dairy Solutions

  This episode was recorded at the 2025 Western Dairy Management Conference in Reno, Nevada. Dr. Sabine Mann, Cornell University; Dr. Will Mustas, Progressive Dairy Solutions; Dr. Don Niles, Dairy Dreams LLC; and Joey Airosa, Airosa Dairy Farms, introduce themselves. (0:48)Dr. Mann outlines the high points of her presentation. Giving an adequate amount of high-quality colostrum quickly after birth is essential to equip the calf with the best chances to stay healthy. Colostrum is more than a solution of water and immunoglobulins, and we are continuing to learn more about other nutrients and growth factors that colostrum contains. (12:03)Dr. Niles and Mr. Airosa talk about colostrum and maternity protocols on their dairies. Each has dedicated maternity staff in charge of postnatal calf care. Don mentions they often have public tours of their dairy and shares some anecdotes. Joey’s maternity staff try to get colostrum in calves within 30 minutes of birth and have worked out a good communication system to ensure seamless calf care when shift changes occur. (13:57)Dr. Mann emphasizes the timing of colostrum delivery is critical. But what about the amount? Should every calf get four liters? Joey notes they bottle feed and have settled on three quarts for Holstein calves and two quarts for Jersey calves. Sabine says research backs that up - calves will not voluntarily drink much more than 3-3.5 liters. Using esophageal feeders to give four liters could be overfeeding in some cases, which could cause slower emptying of the stomach and thus slower arrival and uptake of immunoglobulins at the small intestine. The four liter recommendation came from the idea that good quality colostrum probably had about 50 grams per liter of IgG, and at that time, we wanted to get 200 grams into the calf. Perhaps making a sheet with recommended amounts based on calf weights could be helpful for maternity staff.  Dr. Mann also clarifies that the 50 grams per liter of IgG is not really good quality colostrum. Most herds average about 90-100 grams per liter of IgG in colostrum. She recommends every farm find out how good their colostrum is and optimize feeding amounts from there. (22:45)Dr. Mann notes the importance of making sure dry cows are not deficient in protein supply and ensuring the dry period is long enough to create high-quality colostrum. While it’s commonly thought older cows have better colostrum than young cows, she underlines again the importance of measuring colostrum quality to know for sure. She also highly recommends measuring colostrum quality from individual cows before pooling so that poor colostrum does not dilute good colostrum. (31:04)Dr. Mustas shares some of the challenges he’s seeing on dairies where he consults. What can we do to control the bacteriological quality of colostrum? He notes there’s no reason we can’t get very low bacteria counts pre-pasteurization. Making sure maternity areas are clean and sanitary, udders are prepped very well, and harvesting equipment is not neglected are all great strategies. (35:53)Dr. Mann talks about individual cow variation in colostrum production and some factors that might influence including placental interactions, hormones, and genetics. (38:04)Scott and Sabine discuss some of the research around supplementing with choline during the dry period and subsequent colostrum production. (41:28)Dr. Niles comments that pasteurization of colostrum has been one of the most exciting technologies to come along. On his farm, the pasteurizer has given them much more control over colostrum quality and delivery time. Dr. Mann agrees storage of colostrum has given dairies the ability to be strategic about how they use colostrum, what colostrum they use, and to also plan for seasonal colostrum shortages. She agrees with Dr. Mustas that clean colostrum harvesting equipment is key to low bacterial counts. (44:13)Dr. Mustas talks about how the beef-on-dairy phenomenon has altered colostrum protocols. Calf ranches are giving deductions for poor colostrum scores when calves are received. Some operations even offer premiums or discounts on daily yardage depending on individual calf colostrum scores. (50:21)Joey, Don, and Sabine comment on the importance of finding the right people to work in maternity and instilling the idea that taking care of cows and calves is both a great responsibility and a great honor. (52:56)The panel wraps up with their take-home thoughts. (58:31)Please subscribe and share with your industry friends to invite more people to join us at the Real Science Exchange virtual pub table.  If you want one of our Real Science Exchange t-shirts, screenshot your rating, review, or subscription, and email a picture to anh.marketing@balchem.com. Include your size and mailing address, and we’ll mail you a shirt.

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