By Blake Jackson
Despite declining fluid milk consumption in the U.S., a surge in demand for butter and cheese (milk fat-based products) has led to record overall dairy consumption.
To address this market shift, Penn State researchers have discovered that supplementing dairy cattle feed with 15% whole cottonseed can effectively boost both milk fat concentration and yield. Whole cottonseed, a byproduct of cotton processing rich in unsaturated fatty acids and protein crucial for milk fat production, presents a promising solution.
"Dairy farmers are paid for fat and protein today because people are eating more products that contain these milk solids-we're not drinking as much fluid milk," explained team leader Kevin Harvatine, professor of nutritional physiology. He added that this market demand has driven a decade-long focus on "selecting and managing cows for producing higher milk fat."
The study revealed that cows fed a 15% whole cottonseed-supplemented diet experienced a 0.2% increase in milk fat concentration and a 5% rise in daily fat yield compared to those without the supplement. Notably, the cottonseed diet did not reduce feed intake and had no impact on milk protein concentration or yield.
Conducted at Penn State's dairy barns over 21-day periods with 16 multiparous cows, the research also monitored gossypol, a pigment in cottonseed, in the cows' blood.
Levels remained safely below toxic thresholds. Manure analysis indicated high digestibility, with less than 3% of seeds passing through undigested.
Harvatine highlighted the significance of whole cottonseed's slow release of unsaturated fat in the rumen, minimizing the risk of "biohydrogenation-induced milk fat depression," a condition that can drastically reduce milk fat.
Harvatine noted that while selective breeding has already increased average U.S. milk fat from 3.75% to 4.2% over the past decade, "that brings us to the point of trying to do two things-increase milk fat by feeding additional fat, but then also keeping up with the cows’ demand for making that additional fat. That’s what led us to experimenting with different feed supplements, and one of them is whole cottonseed."
Interestingly, the cottonseed supplementation did not affect methane production and emissions, unlike some other lipid supplements.
The research team, including first author Yusuf Adeniji, concluded that whole cottonseed offers a valuable strategy for dairy farmers to meet the current market demands for milk fat without compromising feed intake or milk protein yield.
Photo Credit: gettyimages-digitalvision
Categories: Pennsylvania, Education, Livestock, Dairy Cattle