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We conducted a trial to study the influence of strain of hen (white vs. brown) and source and percentage of added fat to diet on productive performance and fatty acid (FA) profile of the egg yolk. There were nine dietary treatments: a control diet without added fat and eight diets arranged as a 2 x 4 factorial (5 vs. 10% added tallow, olive, soy, or linseed oil). Each treatment was replicated five times, and the trial lasted 12 wk. White hens produced yolks with more saturated FA (P < 0.001) and less monounsaturated FA (P < 0.001) and polyunsaturated FA (P < 0.05) than brown hens. Fat supplementation improved egg mass output (P < 0.05) and feed efficiency of hens (P < 0.001). Linseed and soy oil diets produced greater egg mass than diets based on tallow or olive oil (59.6, 59.4, 57.9, and 57.1%, respectively; P < 0.001). The proportion of saturated FA in the yolk decreased as the percentage of added fat increased (36.5, 32.3, and 31.0% for diets containing 0, 5, and 10% added fat, respectively; P < 0.001). When the alpha-linolenic acid content of the diets increased from 0 to 0.8%, the arachidonic, docosapentanoic, and docosahexanoic acids in the egg yolk increased. Increases in the alpha-linolenic acid content of the diet over 2.3% did not further augment the concentration of docosapentanoic or docosahexanoic acid of the yolk and, in fact, decreased that of arachidonic acid. Only diets supplemented with linseed oil produced eggs with measurable amounts of eicosapentanoic acid. Diets supplemented with soy oil, with moderate levels of alpha-linolenic acid and high levels of linoleic acid, increased arachidonic and docosahexanoic acids in the egg yolk but not eicosapentanoic acid.

We studied the influence of cereal, heat processing of the cereal, and inclusion of additional fiber in the diet on the productive performance and digestive traits of broilers from 1 to 21 d of age. Twelve treatments were arranged factorially, with 2 cereals (corn and rice), 2 heat-processing treatments of the cereals (raw and cooked), and 3 sources of fiber (none, 3% oat hulls, and 3% soy hulls). Each treatment was replicated 6 (trial 1) or 3 (trial 2) times. Growth traits were recorded in both trials; digestive traits were measured in trial 1, and total tract apparent retention (TTAR) of nutrients was determined in trial 2. Feeding rice improved TTAR of all nutrients and feed conversion from 1 to 21 d of age (P

No abstract

A 42-d trial was conducted to study the influence of exogenous alpha-amylase on digestive and performance traits in broilers fed a corn-soybean meal diet. There were two treatments (control and alpha-amylase supplemented diet) and six replicates (14 Cobb male chicks caged together) per treatment. At 7 d of age, alpha-amylase supplementation improved daily gain by 9.4% (P < or = 0.05) and feed conversion by 4.2% (P < or = 0.01). At the end of the trial, birds fed the alpha-amylase-supplemented diet ate more and grew faster (P < or = 0.05) and hadbetter feed conversion (P < or = 0.10) than broilers fed the control diet. Also, alpha-amylase supplementation improved apparent fecal digestibility of organic matter and starch (P < or = 0.01) and AMEn of the diet (P < or = 0.001). However, no effects were detected for CP or fat digestibility. Nutrient digestibility and AMEn of the diet increased with age (P < or = 0.001); however, no interactions of alpha-amylase x age were observed for any trait. Coefficients of apparent ileal and fecal digestibility of starch at 28 d of age were similar, which indicated that most of the undigested starch was not fermented in the hindgut of the chick. alpha-Amylase supplementation reduced relative pancreas weight (P < or = 0.001) but did not affect the weight of the remaining organs. Age consistently reduced intestinal viscosity and relative weights of all the organs (P < or = 0.001). The data indicated that alpha-amylase supplementation of a corn-soybean meal diet improved digestibility of nutrients and performance of broilers.