No abstract

The effect of corn-canola meal and corn-soybean meal diets on the form and function of the gastrointestinal tract of broiler (meat-type) and White Leghorn (egg-type) cockerels was measured from 14 to 44 and 14 to 86 days of age or 203 to 1,844 and 115 to 1,777 g of body weight, respectively. Dry weights of the empty crop (P less than .01), gizzard (P less than .001), and ceca (P less than .001) relative to live body weight (g/kg) were lighter in broilers than in Leghorns. Canola meal at 370 g/kg diet was associated with increased (P less than .001) dry weight of the gizzard and jejunum relative to body weight. Soybean meal at 370 g/kg diet was associated with increased (P less than .001) dry weight of the ceca relative to body weight. The lengths, relative to a power of body weight of the duodenum (cm/g.187) and jejunum plus ileum (cm/g.240), were longer (P less than .001) in broilers than in Leghorns. The canola meal diet was associated with an increase (P less than .001) in length of the jejunum plus ileum (cm/g.240) relative to a power of body weight. Mean retention time (MRT) of a particle marker, 103ruthenium phenanthroline, increased with body weight in the entire gastrointestinal tract (P less than .001) and in each of its segments except in the proventriculus, where it was not affected by body weight (P greater than .05), and in the gizzard, where it decreased (P less than .05) with body weight. The MRT, adjusted for body weight in the entire gastrointestinal tract of broilers (338.0 +/- 10.8 min) and Leghorns (359.9 +/- 10.8 min), was similar (P greater than .05) but varied significantly in segments of the gut for both type of chicken and diet. Adjusted MRT was shorter in the crop (P less than .001) and gizzard (P less than .001) and longer in the duodenum (P less than .001) and ileum (P less than .01) of broilers than Leghorns. The soybean meal diet was retained for 2.3 min longer in the duodenum (P less than .001) and 84.2 min longer in the ceca (P less than .001) than the canola meal diet, which accounted for the longer (P less than .001) retention of the soybean meal diet in the entire gastrointestinal tract (388.0 +/- 10.6 vs. 309.8 +/- 10.8 min). Segments of the gastrointestinal tract vary in length, weight, and MRT of digesta with dietary composition and type and body weight of chicken.

Sixteen simulated barleys, containing combinations of '7.2'7, 11.21 , 15.17 and 19.27 crtde protein (CP) (air-dry basis) and 0, 10,20 and,30Va hulls, were made from barley (Hordeum vulgare L. 'Bonanza') that was finely ground and air-classified into hulls, starch, protein and fines fractions. These barleys were supplemented with vitamins and minerals and fed in four replicates to 16 pigs, of 20 kg initial weight, in a digestibility trial. Energy digestibility was highly correlared with percent hulls and percent crude fiber (r : -0.9 for both factors; P<0.01). (NRC 1979) was f'ed as a wet mash (2 water:1 feed, wt/wt). Each feeding period comprised 3 days of preliminary feeding followed by 4 days of fecal collection. Feces were collected twice daily immediately after feeding by driving the pigs to a clean room Table I Formulation of dicts used in digcstibility trral (arr-dry basis) Planned level (%) ingredient (

White Leghorn male 4-week-old chicks and adult roosters were used to determine the effect of age on the true metabolizable energy (TME) and nitrogen-corrected true metabolizable energy (TME,,) value of ground yellow corn, dehulled soybean meal, wheat shorts, high-glucosinolate rapeseed meal, and dehydrated alfalfa meal. The TME and TME n values of each ingredient were calculated from its gross energy value and the regression of energy voided as excreta on the weight of feed consumed. Variable intakes of corn and soybean meal were obtained with chicks by feeding different amounts of the feedstuffs and with roosters by varying the duration of the feeding period. Variable intakes of the other ingredients were obtained by the force feeding of the birds.The TME values of the feedstuffs in kcal/g of dry matter for chicks and roosters, respectively, were as follows: corn, 3.93 and 3.98; soybean meal, 3.24 and 3.11; wheat shorts, 3.12 and 3.07; rapeseed meal, 2.24 and 2.50; alfalfa meal, 1.22 and 1.38. The TME n values of the feedstuffs for chicks and roosters, respectively, were as follows: corn, 3.76 and 3.88; soybean meal, 2.85 and 2.87; wheat shorts, 2.92 and 2.94; rapeseed meal, 1.99 and 2.24;alfalfa meal, 1.14 and 1.28. The TME values of soybean meal and rapeseed meal for chicks were 104% (P<.05) and 90% (P<.05), respectively, of the values obtained with roosters. The TME n values of corn and rapeseed meal for chicks were 97% (P<.05) and 89% (P<.01), respectively, of the values for roosters. The TME and TME n values of the other feedstuffs were not affected (P>.05) by the age of the bird.It appears that, with the exception of high-glucosinolate rapeseed meal, TME values obtained with adult roosters can be used in the formulation of diets for young growing birds.

Five samples of corn selected to vary widely in kernel density (test weight per unit volume) were assayed for AMEn with male broiler chickens at 4 wk of age by regression analysis of a multilevel assay and for TMEn with adult White Leghorn roosters. The kernel densities (kilograms per hectoliter), AMEn, and TMEn (kilocalories per gram of DM) values of the corn were, respectively, 72, 3.68, and 3.96; 71, 3.72, and 3.95; 68, 3.66, and 3.90; 62, 3.64, and 3.88; 60, 3.54, and 3.68. Positive relationships were established between AMEn and TMEn (r = .974, P less than .01) or kernel density (r = .875, P less than .05). The assay for TMEn provided a simple, rapid and sensitive method for estimating the AMEn content of corn for chickens. The small (4%) variation in AMEn relative to a large (20%) variation in kernel density precludes the use of kernel density for estimating the AMEn content of corn.