What’s happening to older cows?

What’s happening to older cows?

Author: Balchem Animal Nutrition & Health October 11, 2022 Duration: 1:11:10

Guests: Dr. Ian Lean, Scibus; Dr. Todd Duffield, University of Guelph; Dr. Stephen LeBlanc, University of Guelph

Co-host: Dr. Pete Morrow, Animal Health Specialist

Gathering around the pub to discuss body condition, productivity and the impact older cows have on herds are Dr. Ian Lean, Dr. Todd Duffield and Dr. Stephen LeBlanc. 

Dr. Ian Lean, Scibus Founder and Manager Director and leading authority in dairy cattle medicine, kicked off the conversation to discuss his data set research around cow removal and reproduction. 9:11

Ian noted those involved with the older cow research looked at the disease, reproduction and metabolic data differently than most people. Sharing the impact of various diseases in older cows. 11:03

What is the relationship between production and reproduction? Dr. Stephen LeBlanc, a veterinarian professor at the University of Guelph, added this is the common question he receives. Sharing the challenge as dairy scientists, Stephen said the importance of figuring out how to support a cow’s lifespan by choice instead of failing to stay healthy, fertile and productive. 15:20

Dr. Todd Duffield, a professor at the University of Guelph, believes there are misconceptions about older cow production and reproduction. He suggests that instead of wanting cows to live forever, profitability or not, he adds that it’s all really about limiting or reducing the farmers' decisions and optimizing the cows' health and performance. 20:29

Stephen discusses a win-win approach for the producer, herd and cow itself - optimization and economic longevity. But how do you create farm conditions to know when the optimum time to cull is, Stephen added. 27:04

Does a different feeding program matter, asked Ian. From the first webinar, he added that the older cows you could leave on 28 days and still have increased milk production and solids. He suggested when formulating diets for the average cow; he calculates eight pounds more and about three to five kilos more milk than the average cow. 33:18

Stephen added cows are both ketotic and have low blood glucose ultimately show varying production outcomes. Suggesting early lactation studies, tough calving and blood BHB all having different risk categories for each animal, said Stephen. 48:57

Rounding out the conversation, Stephen closed by suggesting there is an opportunity to possibly rethink some nutritional paradigms in terms of protein and bone metabolism. 1:00:38

Additionally, Todd mentioned the direct difference between heifers and older cows. Adding the importance in studying management and feeding qualities for both production and reproduction optimization. 1:04:39

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Ever wonder what animal scientists talk about after the formal presentations are over and the notebooks are put away? Real Science Exchange-Dairy captures that exact spirit, moving beyond the lecture hall to explore the ideas shaping dairy and animal nutrition. Presented by Balchem Animal Nutrition & Health, this series feels more like a lively, insightful table conversation among colleagues than a staged interview. You’ll hear leading researchers and experts discuss pressing topics in the field, but in a relaxed, unfiltered way that reveals the person behind the data. The dialogue is driven by genuine curiosity and a shared passion for natural sciences, covering everything from emerging research to practical applications. Each episode is an exchange of perspectives, offering a range of new ideas that challenge conventional thinking. It’s a podcast for anyone interested in the real-world science that impacts animal health and productivity, delivered with the authenticity of a discussion among friends. Tune in for thoughtful, accessible conversations that connect complex concepts to the bigger picture of life and scientific discovery.
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