Bonus Episode: Prepartum Calcium Strategy, Calcidiol, and Cow Performance

The episode opens with Dr. Overton discussing his work at Cornell University and how Dr. Somare came to Cornell from Argentina on a Fulbright scholarship after gaining experience in the feed industry and teaching. Dr. Somare also introduces the poster he is presenting at the meeting. (00:00 – 01:28) Dr. Somare explains that the study evaluated whether combining zeolite and calcidiol could positively affect mineral metabolism, calcium regulation, and milk performance during early lactation. The study enrolled 92 multiparous Holstein cows in four groups involving either a negative DCAD diet or zeolite feeding, with one group under each strategy receiving calcidiol. The zeolite groups received around 300 g. (02:34 – 04:13) Looking at the results, Dr. Somare explains how cows were retrospectively classified as dyscalcemic or eucalcemic based on calcium recovery, with dyscalcemic cows remaining below 2.2 millimoles per liter on day four. Dr. Overton notes that previous work used 500 grams of zeolite per day, while the 300-gram dose evaluated here was more economical and appeared to be just as effective. Around 90% of cows fed zeolite during the prepartum period were eucalcemic. (04:14 – 06:27) Moving into practical application, Dr. Somare describes zeolite as a lower-management strategy compared with negative DCAD diets, which require urine pH monitoring and forage mineral analysis. When asked about dosing, he says the appropriate amount will probably depend on the mineral balance of the diet, but the study achieved good results with 300 grams. (06:28 – 08:09) Dr. Overton adds that recommendations may move up or down depending on the grams of phosphorus in the diet. He also emphasizes that negative DCAD diets continue to work well and that many herds and nutritionists have extensive experience with them, describing both approaches as viable options. (09:01 – End) 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 [anh.marketing@balchem.com](mailto:anh.marketing@balchem.com). Include your size and mailing address, and we'll mail you a shirt.