| Popis: |
In Experiments 1 and 2, dead broilers (3 and 5 wk old) and dead turkeys (6 and 12 wk old), and broiler feathers were obtained from commercial sources and evaluated for nutritional contribution when co-extruded with soybean meal (48% CP). Samples of each age of dead birds and two feather treatments, with and without 5.13% proteolytic enzyme premix (INSTA-PRO®), were blended with soybean meal in an 25:75 ratio (wt/wt, wet basis) and processed through an INSTA-PRO® extruder. The resulting six extruded products were used in formulating isocaloric and isonitrogenous diets and were compared with a diet containing corn-soybean meal or corn-soybean meal with commercial feather meal when fed to broilers from 1 to 21 days of age. In Experiment 1, feeding diets containing dead broilers supported higher (P ≤ .05) body weight than those receiving the corn-soybean meal control diet. There was no difference (P > .05) in feed conversion. Enzyme treatment of the feathers improved growth rate but not feed conversion over the untreated feather diet in Experiment 1. In Experiment 2, dead poultry and enzyme-treated feather extruded products were good feed ingredients for broilers with feed efficiency and growth responses comparable to the corn-soybean meal control diet. In Experiments 3 and 4, centrifuged eggshells from egg-breaking plants (Source A or B), centrifuged hatchery solid (Source C or D), centrifuged hatchery solid plus liquid (Source C or D), and mechanically deboned turkey frame residue were each blended with ground corn to produce mixtures with 15 to 25% moisture and processed through an INSTA-PRO® extruder. Two experiments involving 480 Hy-Line® 36 laying hens were conducted for three 28-day periods to evaluate hen performance and egg quality when the extruded products were incorporated into the diet. No differences were found (P The microbiological test (total aerobic count) indicated that the pre-extrusion blended mixtures had significant numbers of colony-forming units per gram of sample. The extruded products that exited from the extruder barrel were free of aerobic microorganisms. The results of these studies indicated that high temperature-short time extrusion is an alternative method for converting these poultry industry residues into feedstuffs. |
