Canola screenings as a fiber source in barley-based feedlot diets: effects on rumen fermentation and performance of steers

Abstract

. 2000. Canola screenings as a fiber source in barley-based feedlot diets: effects on rumen fermentation and performance of steers. Can. J. Anim. Sci. 80: [161][162][163][164][165][166][167][168]. Two experiments were conducted to determine the feeding value of canola screenings in combination with barley grain for beef steers. Four dietary treatments were used. These included canola screenings:barley grain ratios of 100:0; 75:25, 50:50, and 25:75 (as-fed basis). In a metabolic trial, the effects of dietary treatment on ruminal fermentation parameters were determined in a 4 × 4 Latin square design experiment using four ruminally fistulated steers. In a production trial, 66 individually fed steers were used in an 83-d finishing trial to determine the performance and carcass characteristics of feedlot cattle fed different levels of canola screenings. A barley grain/barley silage-based control diet was also fed for comparison purposes. Ruminal pH decreased (P < 0.05) while total volatile fatty acid concentrations increased (P < 0.05) as the level of barley grain in the diet increased. Ruminal NH 3 -N followed a pattern (P < 0.05) similar to that of pH. Inclusion level of canola screenings had no effect on DM intake. However, ADG and feed efficiency increased (P < 0.05) as the level of barley grain in the diet increased. Increasing the level of barley grain in the finishing diet decreased (P < 0.05) lean meat yield and increased (P < 0.05) carcass fat. It was concluded that canola screenings can be included as a source of fiber in barley-based diets. However, levels in excess of 500 g kg -1 reduced the performance of feedlot steers. Performance and cost of gain with 250 and 500 g kg -1 canola screenings in barley-based finishing diets were comparable with those fed an 800 g kg -1 barley grain and 200 g kg -1 barley silage diet. Formulation of finishing diets for beef cattle to attain desired levels of productivity can involve numerous feed ingredients. Some factors influencing choice of dietary ingredients include cost, availability, animal acceptability and desired level of performance. Current finishing rations for western Canadian beef cattle are formulated with limited roughage levels (50 to 150 g kg -1 DM basis). The use of low roughage diets allows for the formulation of energydense diets and improves the ability to mix and deliver large quantities of feed. In finishing diets, roughages are primari-

Evaluation of a phase-feeding strategy utilizing high-lipid high-fibre byproduct pellets in diets for feedlot steers

“…The primary reasons for the lower digestibility are not known and could be attributed to (1) high lignin content in some of the byproduct feeds, (2) small particle size of the feeds within the high-lipid high-fibre byproduct pellets, and (3) negative associative effects of the lipid on rumen fermentation. Similar findings were also seen previously (Pylot et al 2000) where canola screenings were used to replace a substantial portion of barley grain resulting in lower ADG and G:F.…”

“…As a consequence of increased grain prices, feedlot operators have been searching for viable alternatives to cereal grain as energy sources for finishing cattle. Studies evaluating the use of byproducts from the cereal grain, oilseed, and bioethanol industries for finishing cattle have demonstrated that comparable carcass quality and average daily gain (ADG) can be attained, relative to barley grain, although the inclusion rate of the byproducts in diets may affect performance (Pylot et al 2000;Amat et al 2012;Yang et al 2012). Most previous studies have investigated dietary byproduct inclusion in isolation rather than utilizing a combination of byproducts.…”

Effect of feeding strategically blended feed pellets on rumen fermentation and nutrient digestion

“…Elliot et al (1997) reported that replacing corn starch with different sources of fat resulted in an increase in ruminal pH. Similar results were reported in cannulated steers when canola screenings replaced barley grain (Pylot et al 1999b). When fermentation of carbohydrate occurs, protons are released, thus decreasing pH; however, fat sources with high degree of unsaturated fatty acids capture protons when they are hydrogenated in the rumen (Doreau and Chilliard 1997).…”

“…(1 (Moore et al 1986;Brandt 1995;Pylot et al 1999b). In the current study, the average dietary fat intake on the HF diets was 715 g d (1 .…”

“…For example, Pylot et al (1999a) found that dry matter intake (DMI) was not affected at levels up to 10% of dietary fat coming from pelleted canola screenings. However, in a companion study, these workers showed that ADG and feed efficiency were improved when fat from canola screenings was replaced with barley grain (Pylot et al 1999b). Moreover, replacement of barley grain with corn or wheat distillers' dried grains with solubles (DDGS) improved animal performance (Walter et al 2010), although nitrogen and phosphorus excretion increased with increasing levels of both DDGS sources (Walter et al 2011).…”