Consumption of high-protein foods, such as meat, doesn't cause excess calcium loss as previously believed. That's according to a two-year research project funded by the beef checkoff and conducted by USDA's Agricultural Research Service (ARS).
The research evaluated calcium retention in women on diets of varying amounts of protein and calcium — high protein, high calcium; high protein, low calcium; and low protein, low calcium.
“The research confirms findings from other studies that show protein from meat doesn't compromise calcium status. In fact, it can increase calcium absorption and has beneficial effects on bone health,” says Sharon Miller, National Cattlemen's Beef Association director of nutrition research.
The study found diets high in meat, which can comprise up to 20% of an individual's intake, don't increase overall calcium loss, regardless of whether calcium intake is low or high. And, eating the recommended amounts of meat when calcium intake was low was beneficial as it helped retain the calcium consumed.
It also was noted that consuming protein from such sources as beef is beneficial to bone health because beef contains amino acids and bone-building nutrients such as zinc and phosphorous.
“Bone health is of particular importance to post-menopausal women, but bone health begins at childhood. All consumers need a nutrient-rich diet,” Miller says. “That's why research has such positive implications for both beef and dairy producers.”
— Cattlemen's Beef Board
Improved feed efficiency, accelerated marbling deposition and decreased age at slaughter are proven traits of early-weaned steers. Kansas State University researchers took the investigation a step further by studying feedlot performance of crossbred Hereford x Angus bull and steer calves after early weaning.
The treatments included: 1) early-weaned (117 days of age) bulls; 2) early-weaned steers; 3) normal-weaned (220 days of age) bulls; and 4) normal-weaned steers. At 117 days of age, calves assigned to early-weaning were weaned, weighed and vaccinated before being separated into pens of either bulls or steers and fed a complete starter ration.
The calves designated for normal weaning summered with cows on pasture. At an average age of 218 days, calves were weaned, weighed and separated into pens.
At average ages of 269 days and 328 days, calves were weighed. Ultrasound determined backfat and marbling score.
Early-weaned calves had greater ADG from the time of early weaning to feedlot entry than normal-weaned calves. The results suggest early-weaned cattle gain more rapidly during the early post-weaning period than normal-weaned calves. Researchers found that during the finishing phase, early-weaned calves lose their gain advantage but still have heavier final weights than normal-weaned cattle.
Bulls and steers had a similar weight per day of age, even though bulls gain weight faster than steers due to anabolic effects of testosterone. Researchers thought the lack of difference came from the implant regimen for steers.
— Kansas State University 2005 Cattlemen's Day Beef Cattle Research
Specially formulated composts can minimize phosphorous runoff and reduce contamination of water supplies.
Applying manure and composts as nitrogen fertilizer to fields and pastures often adds more phosphorous than plants need leading to possible excess phosphorous runoff and water contamination.
ARS agronomists, searching for ways to make phosphorous less water-soluble, or to increase the ability for manure and composts to retain the phosphorous, have found composts high in iron increase phosphorous retention. These can be added as chemical additives or by mixing by-products rich in iron or aluminum with the manure before composting.
Many states have begun implementing manure management regulations aimed at protecting groundwater, streams and other water sources from phosphorus runoff. Some states are using a management tool called the Phosphorous Index to assess the risk of phosphorous loss from fields to surface water.
The ARS findings should help livestock producers limit phosphorous runoff as they face tougher restrictions on soil and water quality.
To study the significance of ultrasound estimates to carcass quality grade, Canadian researchers used ultrasound-estimated fat cover (FT), ribeye area (REA) and intramuscular fat (IMF).
University of Prince Edward Island scientists studied 487 calves from eight Prince Edward Island feedlots. When finished, 34% of the animals graded Canadian AAA (equivalent to USDA Choice), 57% graded AA (Select) and 9% graded A (Standard).
The ultrasound component determined that carcass attributes were significantly associated with slaughter grade. When comparing the results to ultrasound data, researchers found the highest relationship between the ultrasound results and quality grade was with IMF, followed by FT, and then REA.
The scientists also found the other significant predictors were feedlot of origin, carcass weight and days on feed. (G. P. Keefe, et al, Can. J. Anim. Sci. 84: 165-170.)
— TAMU February Beef Cattle Browsing