Peroxide treatment of feather meal for finishing cattle

Heifers (756 lb, 312 head) were used in a finishing study to evaluate the effects of peroxide-treated feather meal on animal performance and carcass characteristics. Diets contained 3.0% of peroxide-treated or untreated feather meal, and were fed ad libitum. Treatment of feather meal with hydrogen peroxide increased in situ protein degradabilities by 56%, but did not significantly alter feed intake or feed efficiencies. Although not statistically different, gains were 2.1% greater for heifers fed peroxide-treated feather meal. Hot carcass weights also averaged 6 pounds heavier for heifers fed diets containing peroxide-treated feather meal. Marbling tended to be lower, but carcasses grading USDA Choice tended to be higher for heifers fed diets containing peroxide-treated feather meal.


Introduction
Supplementation of high-grain diets with rumen-degradable, true protein can improve performance of finishing cattle, whereas adding ruminal escape protein is generally ineffective.This suggests that the metabolizable protein supplied by the basal diet is adequate.Improved performance in response to rumen degradable, true protein supplementation is likely due to improvements in dietary energy utilization rather than to metabolizable protein supply.Because feather meal is high in ruminal escape protein (70%), our objective was to find if increasing its ruminal degradation would improve its value in finishing diets.

Experimental Procedures
Three hundred twelve crossbred heifers (756 lb) were used in a randomized block design experiment to evaluate the effects of peroxide treatment of feather meal on animal performance and carcass characteristics.Heifers were individually weighed and allotted to one of three blocks based on weight and previous treatment and, within each block, were stratified by weight to one of eight pens (12 to 13 heifers per pen).Treatments were two finishing diets containing untreated or peroxide-treated feather meal (Table 1), which were fed to heifers once daily on an ad libitum basis.The three blocks of heifers were fed for 117, 127, and 159 days before final pen weights were obtained and heifers were shipped to a commercial slaughter facility.
Feather meal was treated by adding 14.3 lb of 35% feed-grade hydrogen peroxide solution to 100 lb of feather meal (as received basis) while being continuously mixed.This supplied approximately 5 grams of hydrogen peroxide per 100 grams of feather meal.After mixing for 15 minutes, the treated feather meal was allowed to cool by spreading it to a depth of 12 inches on a clean concrete surface.
Protein degradabilities were measured using an in situ bag technique.Duplicate polyester bags (5 × 10 cm; pore size = 50 µm), containing either no sample (blank) or 1.25 g of soybean meal (standard), feather meal, or peroxide-treated feather meal, were sealed using an impulse heat sealer and soaked in warm tap water before being suspended for 12 hours in the rumen of a cannulated Holstein steer fed a 50% concentrate diet.Bags were rinsed, dried in a forced-air oven at 55 o C, and analyzed for nitrogen.

Results and Discussion
Chemical treatment of feather meal with hydrogen peroxide increased in situ protein degradability from 32% to 50%, a 56% increase.Replacement of untreated with peroxide-treated feather meal in the finishing diet of heifers had no effect on feed intakes (Table 2).Average daily gains, although not statistically different, were 2.1% greater for heifers fed diets containing peroxide-treated feather meal.Feed efficiencies were not greatly affected by treatment.Hot carcass weights for heifers fed the diets containing peroxidetreated feather meal were numerically, but not significantly, heavier (6 lb increase).Dressing percent was not different between diets.Kidney, pelvic and heart fat and twelfth rib back fat were not different between diets, but marbling tended to be lower (P=.16) for heifers fed peroxidetreated feather meal.The percentage of carcasses grading USDA choice also tended (P=.06) to be higher for heifers fed peroxide-treated feather meal diets, but carcasses grading USDA prime were numerically lower.As a result, there were no large differences in carcasses grading USDA choice or better.
Treating of feather meal with peroxide increased in situ protein degradability, and tended to improve performance and carcass characteristics of cattle.

Table 2 . Effect of Peroxide-Treatment of Feather Meal on the Performance and Carcass Characteristics of Finishing Heifers
a Computed by applying a 4% shrink to the final weights.b KPH = kidney, pelvic & heart.c Sl = Slight.