Effects of treating lignocellulosics with alkaline hydrogen peroxide on feed intake and digestion by dairy cattle

Lower nutrient digestibility and feed intake has limited the amount of lignocellulosic residues and by-products fed in the dairy production system. The alkaline hydrogen peroxide (AHP) treatment of lignocellulosics has been shown to increase degradation of structural carbohydrates by ruminal microbes. Therefore, four experiments were conducted to investigate the effects of AHP-treated wheat straw (WS) or oat hulls (OH) on feed intake, nutrient digestion, ruminal fermentation, and production responses by dairy cattle.In experiment 1, twelve Holstein cows in early lactation were used in 3 replications of a 4 x 4 Latin square design. Treatments contained 0, 12.5, 25.0, or 37.5% AHP-WS in the diet. Cows fed AHP-WS had slightly lower dry matter (DM) intakes and similar yields of 4% fat-corrected milk. There was a trend towards a higher milk fat percentage for cows fed the AHP-WS diets. Diets containing AHP-WS had increased neutral detergent fiber (NDF) and acid detergent fiber digestibilities which resulted in similar intakes of digestible fiber among the treatments.In experiment 2, eight Holstein cows in mid-lactation were used in 2 replications of a 4 x 4 Latin square design. Treatments contained 0, 20.0, 40.1, or 60.0% AHP-WS in the diet. Cows fed up to 40.1% AHP-WS in the diet had similar DM intakes and milk yields compared to cows fed the 0% AHP-WS diet containing alfalfa haylage and corn silage. Feeding the 60.0% AHP-WS diet noticeably lowered DM intake and milk production. There were decreases in milk fat and milk protein percentages for cows fed the 40.1 and 60.0% AHP-WS diets. Addition of AHP-WS to the diet increased NDF digestibilities and digestible NDF intakes compared to cows fed the diet containing 0% AHP-WS.In experiment 3, twelve Holstein cows in mid-lactation were used in 3 replications of a 4 x 4 Latin square design. Treatments contained 0, 17.2, 34.5, or 52.1% AHP-OH in the diet. Cows fed the 17.2 and 34.5% AHP-OH diets had higher DM intakes and greater yields of 4% fat-corrected milk compared to cows fed the 0% and 52.1% AHP-OH diets. Addition of AHP-OH to the diet resulted in higher digestible nutrient intakes and increased NDF digestibilities. Milk protein percentage decreased while milk fat percentage increased upon inclusion of dietary AHP-OH.In experiment 4, twelve Holstein heifers were used in 3 replications of a 4 x 4 Latin square design. Treatments contained 0, 20.4, 40.6, or 60.5% AHP-OH in the diet. The inclusion of AHP-OH in the diet resulted in higher nutrient intakes, nutrient digestibilities, and digestible nutrient intakes, except for crude protein, compared to heifers fed alfalfa haylage (0% AHP-OH). The addition of dietary AHP-OH increased the acetate to propionate ratio which suggested a fiber-type fermentation in the rumen.U of I OnlyETDs are only available to UIUC Users without author permissio