Professor Bill Weiss:
Bettering Dairy’s Bottom Line
Organizers of this year’s Tri-State Dairy Nutrition Conference dedicated the 2021 Proceedings to Professor Bill Weiss, who retired in January from the Department of Animal Sciences at the Ohio State University. His research career focused on forage utilization, energy value of feeds, feed management, and vitamin and mineral requirements.
“He developed a world-renown research program,” the Proceedings state, “but he never lost sight to sharing his research with stakeholders in Ohio and the Tri-State area.”
Moreover, Bill’s research has never lost sight of the bottom line for dairy nutritionists and the producers they serve. We need ongoing R&D, he said at Tri-State, “to keep the dairy industry as a competitive contributor to the human food supply.”
Pointing the way
Over the past 30 years, milk per cow has increased an average of 290 lbs. per year, thanks to improved dairy genetics, facilities and management, and nutrition.
Today dairy nutrition has improved animal health, not just milk production. Bill noted that increased computing power brings more sophisticated ration evaluation and formulation software, both to improve diets and better predict animal performance. Looking ahead, he expected research and technology to “allow nutritionists to incorporate animal and diet composition variation into their formulation goals.”
For essential minerals, he says, “bioavailability will become even more important and additional fine tuning of requirements… can reduce the degree of overfeeding minerals that is common today.”
“Compared with minerals, we have learned less about vitamin nutrition,” Bill notes. He highlights vitamins A and E for which supplementation rates increased “mostly because of the data showing positive effects on mammary gland health.” Recent studies with greater vitamin D supplementation show “profound effects on immune function.” He expects much more research in this area.
He points out that many B-vitamins are extensively metabolized in the rumen and rumen protected forms of some vitamins are available: “Whether supplementation with these products is profitable has yet to be definitely determined.”
When it comes to feed and diet evaluation and formulation, Bill says, “We have gone from balancing for a few nutrients (CP, NEL, fiber, Ca, and P) to using complex supply models and formulating for dozens of nutrients.” He adds that commercial feed labs now routinely analyze for components that previously could only be done by university research labs: “For example, most labs can now measure in vitro digestibility of neutral detergent fiber (IVNDFD)…. Some labs can measure in situ disappearance of CP which is needed to estimate rumen degradable and undegradable protein.”
Bottom line — IOFC
The demand to increase dairy income over feed costs (IOFC) provides constant pressure to accurately determine the value of feedstuffs in terms of milk production and cow health. Complicating the formulation challenge is variation in the measurable variables, particularly feedstuffs and cows.
With increasing computer power, Bill looks forward to the development of “stochastic formulation,” which would base the formulation goal not on specific values but on probabilities. “For example, a diet might be formulated to contain at least 16% CP, 80% of the time. This approach incorporates risk into formulation strategies and should ultimately result in less expensive and safer diets.”
The next step, he says, is to incorporate animal variation into our formulation systems: “At best, current requirements represent averages. For example, an average 1450 lb. cow producing 85 lb. of milk may need 45 g/day of sulfur to meet her requirement. However, not all 1450 lb. cows producing 85 lb. of milk need 45 g/day of sulfur. Some cows will need more and other less.”
On-farm technology, Bill notes, now “allows cows to be housed in groups but evaluated and even managed as individuals.” And the cost of measuring individual milk yields is coming down. Other technology permits numerous individual measures, including rumination time, rumen pH, and milk composition.
Professor Weiss reminded Tri-State of the dairy cow’s powerful potential: “Ruminants have the ability of increasing the human food supply without directly competing for nutrients.”
Bill looks forward to dairy diets that use more human food byproducts more effectively. Also, more efficient feeding systems are going to produce more desirable dairy products. He points to enriching milk with specific vitamins and minerals, altering milk fatty acid profiles, or changing milk protein characteristics.
And as always in the Tri-State tradition: “We need to continue to develop better ways to convert research information into on-farm application.”
For the 2021 Tri-State program click here
For complete proceedings, including Bill’s remarks in full, click here and use password TRISTATE2021!