COMPOSITION OF MEAT AND DRIP. Utilization of Unextracted Soybeans by Broiler Chicks

Transcription

1 COMPOSITION OF MEAT AND DRIP 11 IS tions existing within the principal muscles composing the poultry carcass. Poultry Sci. 25: 405. Marion, W. W., and W. J. Stadelman, Effect of various freezing methods on quality of poultry meat. Food Technol. 72 : Minor, L. J., Identification of some chemical components in chicken flavor. Ph.D. Thesis, Michigan State University. Moran, T., and H. P. Hale, Science of the meat industry. J. Soc. Chem. Ind. 10: Pearson, A. M., and J. I. Miller, The influence of rate of freezing and length of freezer storage upon the quality of beef of known origin. J. Animal Sci. 9 : Pearson, A. M., R. G. West and R. W. Luecke, The vitamin and amino acid content of drip obtained upon defrosting frozen pork. Food Res. 24: NUMEROUS workers have reported on various ways to utilize unextracted soybeans in chick diets. These methods, which have included autoclaving, cooking, extruding, infra red cooking, and mechanical flaking and pelleting, have been extensively reviewed by Featherston and Rogler (1966) and White et al. (1967). The latter report was largely concerned with two processes for preparing unextracted soybeans, namely, infra red cooking and extruding. They found that these two methods of preparation supported maximum chick growth when compared to those fed diets containing solvent extracted soybean meal. The experiments reported herein were 1 Present address: Department of Poultry Science, Cornell University, Ithaca, N.Y. Sair, L., and W. H. Cook, 1938 a. Effect of precooling and rate of freezing on the quality of dressed poultry. Can. J. Res. 16 D: Sair, L., and W. H. Cook, 1938 b. Relations of ph to drip formation in meat. Can. J. Res. 16 D: Spencer, J. V., W. E. Matson, W. J. Stadelman and M. C. Ahrens, The effect of cooling and freezing procedures on consumer acceptability factors of turkey meat. Food Tech. 10: Swanson, M. H., and H. J. Sloan, Some protein changes in stored and frozen poultry. Poultry Sci. 32 : Wilkinson, R. J., and L. E. Dawson, Tenderness and juiciness of turkey roasts cooked to different temperatures. Poultry Sci. 46: Utilization of Unextracted Soybeans by Broiler Chicks 2. INFLUENCE OF PELLETING AND REGRINDING ON DIETS WITH INFRA RED COOKED AND EXTRUDED SOYBEANS S. J. HULL, 1 P. W. WALDROUP AND E. L. STEPHENSON Department of Animal Sciences, University of Arkansas, Fayetteville, Arkansas (Received for publication November 17, 1967) conducted to further evaluate these two methods of processing unextracted soybeans for broiler diets and to determine the influence of pelleting and regrinding on the nutritive value of diets containing various soybean preparations. MATERIALS AND METHODS Experiment 1. In this and the subsequent experiment in this report, solvent extracted soybean meal and raw whole soybeans were obtained from the lot of beans to increase uniformity of samples. The raw whole soybeans were divided into two portions and subjected to further treatment. One was cooked by the infra red process and the other was extruded. A complete description of processing conditions is given in the report by White et al. (1967). Nitrogen and fat content of the soybean

2 1116 S. J. HULL, P. W. WALDROUP AND E. L. STEPHENSON TABLE 1.Composition of diets Ingredient Fish meal (65% protein) Alfalfa meal (17% protein) Soybean oil Yellow corn meal Soybean meal (50% protein) Infra red cooked soybeans Extruded soybeans Calcium carbonate Dicalcium phosphate Iodized salt Vitamin premix 1 Trace mineral mix 2 DL-methionine Lyamine-50 Chromic oxide Sand Total Calculated analysis: Metabolizable energy, kcal./kg. % Protein % Calcium % Phosphorus % Methionine-!-cystine , Diet number 2 % of diet , , Supplies per kg. of diet: 6,600 I.U. vit. A, 2,200 I.C.U. vit. D 3, 22 I.U. vit. E, 1.1 mg. vit. K, 6.6 mg. riboflavin, 17.6 mg. pantothenic acid, 44 mg. niacin, 1870 mg. choline, 11 meg. vit. Bi 2, 1.1 mg. folic acid, % ethoxyquin. 2 Supplies 100 p.p.m. Fe, 100 p.p.m. Mn, 10 p.p.m. Cu, 1 p.p.m. Iodine. products was determined by the Kjeldahl method and other extraction following the procedures outlined by the A. O. A. C. (1960). From this information, diets were formulated on an isonitrogenous and isocaloric basis. Soybean oil was added to the feed containing soybean meal so that each of the soybean sources contributed the same amount of protein and oil to the diets. In this trial, diets containing solvent extracted soybean meal were compared to feeds with either infra red cooked or extruded soybeans. The composition of the diets is given in Table 1. Each was fed in mash and pelleted forms to give a total of 6 experimental treatments. Five male and five female day-old broiler chicks (Hubbard X Ledbreast) were randomly divided into 60 groups and assigned to compartments in electrically heated battery brooders with raised wire floors. Each of the six experimental treatments was fed ad libitum to 10 groups of chicks from day-old to 28 days of age at which time the experiment was terminated. Body weights and feed consumption data were subjected to the analysis of variance as outlined by Steele and Torrie (1960) with significant differences between treatment means determined by the multiple range test of Duncan (19SS). Statements of statistical significance are based on probability level of P <.05. Experiment 2. The purpose of this experiment was to study further the value of infra red cooked and extruded soybeans in

3 UNEXTRACTED SOYBEANS 1117 broiler diets and to study the effects of pelleting and regrinding the diets on performance. Samples of whole soybeans and solvent extracted soybean meal were obtained from the same lot of beans and the whole beans subjected to infra red cooking and extruding as previously described. Three experimental diets in which the solvent extracted soybean meal, the infra red cooked soybeans and the extruded soybeans contributed the same amount of protein were compared (Table 1). Each of these diets was fed in three forms: allmeal, pellets, and reground pellets. This resulted in a total of 9 experimental treatments. Day-old broiler chicks (Hubbard X Ledbreast) were assigned to compartments in battery brooders. Six groups of 3 males and 3 females were assigned to each of the dietary treatments and fed the diets ad libitum from day-old to 35 days of age. At this time the experiment was terminated and the data subjected to statistical analysis as previously described. Fat digestibility was determined on each of the diets. Chromic oxide was added to the diets as an indicator at a level of 0.3%. Fecal samples were collected for three consecutive 24-hour periods during the last week. The three samples were pooled, homogenized, and analyzed for fat and chromic oxide content. Chromic oxide content was determined by the method of Schurch (1950) while fat was determined by ether extraction. The following equation was used to calculate the milligrams of fat digested per gram of dry diet. Digestion coefficients were calculated from the values thus obtained. TABLE 2.Effect of different methods of processing whole soybeans on performance of broilers {Experiment 1) Protein source Diet form 28 day body weight (gm.) 1 Feed/ gain 1 1. Soybean meal Mash 524 b 1.46 s 2. Infra red cooked Mash 460" Extruded Mash 506 b 1.57 b 4. Soybean meal Pellet 527 b 1.47» 5. Infra red cooked Pellet ab 6. Extruded Pellet 530 bo 1.46* 1 Means bearing the same superscript do not, differ significantly P= <.05. RESULTS AND DISCUSSION Experiment 1. When the three soybean sources were compared in all mash broiler diets, chicks fed the diets containing solvent extracted soybean meal and the extruded soybeans were significantly greater in body weight than chicks fed the diet with infra red cooked soybeans (Table 2). When the feeds were pelleted, growth of chicks receiving infra red cooked soybeans was significantly improved. The improvement in growth of chicks fed the diet containing extruded soybeans approached significance. A comparison of chick weights among the three sources of soybeans when fed in pelleted form indicated that no significant difference existed. When comparing the soybean sources fed in mash form, chicks fed the diet with the solvent extracted soybean meal were more efficient in converting feed to gain than those fed the infra red cooked or extruded soybeans. Pelleting did not affect the response when feeds contained solvent extracted soybean meal, but it significantly mg. fat digested gm. dry diet mg. fat mg. Cr 2 03 gm. excreta gm. diet mg. fat/gm. mg. Cr 2 03 per gm. excreta gm. dry matter per gm. diet

4 1118 S. J. HULL, P. W. WALDROUP AND E. L. STEPHENSON TABLE 3.Effect of different methods of processing soybeans and form of diet on performance of broilers {Experiment 2) Protein Diet body Feed/ JL S«_ source form weight gain 1 bllitv 1 (gm.) 1 1. Soybean meal Mash 660 * 1.56 b Infrared cooked Mash 560 a 1.81" 75.7 a 3. Extruded Mash 632 bo l.s5 b Soybean meal Pellet 677 od 1.48 ab 92.6" 5. Infra red cooked Pellet 671 od 1.51 ab 90.0 f 6. Extruded Pellet 713 d 1.44" 91.8«7. Soybean meal Reground b 88.8«8. Infra red cooked Reground 584 ab Extruded Reground 670 od l.s7 b 85.9 d 1 Means bearing the same superscript do not differ significantly (P = <.05). improved the feed utilization on diets with the infra red cooked or extruded soybeans. There was no significant difference in feed utilization among any of the sources when the feeds were in pelleted form. These results agree with the report of White et at. (1967) that infra red cooked and extruded soybeans may be used to replace solvent extracted soybean meal in broiler diets. The improvement in performance following pelleting is in agreement with the report by Carew and Nesheim (1962). Experiment 2. When diets containing the various soybean sources were fed in mash form, feeds containing solvent extracted soybean meal or the extruded soybeans supported equal body weight gains and efficiency of feed utilization (Table 3). The diet containing the infra red cooked soybeans was significantly less effective. Pelleting the feed containing solvent extracted soybean meal resulted in a slight but non-significant increase in body weight gain and improvement in feed utilization. Performance on the pelleted diets containing the infra red cooked and extruded soybeans was significantly improved in regard to both body weight gain and efficiency of feed utilization. A comparison of the diets containing the various soybean products when fed in pelleted form revealed no significant differences in body weight gain or efficiency of feed utilization. When pelleted diets were fed in a reground form, chicks fed the feed containing solvent extracted soybean meal were lighter in body weight than those fed similar diets in mash or pellet form, but the difference was not statistically significant. Chicks fed the reground pellet feed containing infra red cooked soybeans were significantly lighter than those fed a similar diet in pellet form, but not statistically different from chicks fed the diet containing infra red cooked soybeans in mash form. Regrinding the pelleted feed containing the extruded soybeans resulted in a decrease in body weight when compared to the chicks fed the same diet in pellet form; however, this difference was not statistically significant. Chicks fed the reground extruded soybean feed were heavier than those fed a similar diet in mash form, but again this difference was not statistically significant. Featherston and Rogler (1966) reported that pelleting and regrinding of heated soybeans alone resulted in an improvement in chick growth which approached that of chicks fed the soybean meal basal. However, in the experiment reported herein the entire diet was pelleted and reground. These changes in body weight gain resulting from diet forms and soybean sources were reflected also in the feed:gain ratios. The digestibility of the ether extract portion was similar for the feed containing solvent extracted soybean meal plus soybean oil and for the diet with extruded whole soybeans. The digestibility of both feeds was increased by pelleting. The fat in both sources was digested to a greater degree than that present in the infra red cooked soybeans. This is probably explained by the fact that the infra red

5 UNEXTEACTED SOYBEANS 1119 cooked beans had been cooked whole and then reground through a y 32 inch screen. Thus, the cell rupture was probably not as complete as in the extruded soybeans. The extrusion process is designed to rupture the cells to release the oil inside. The high digestibility of the oil in the extruded soybeans in comparison to the added soybean oil in the soybean meal diet supported this premise. Pelleting the feeds containing the three soybean sources resulted in significant improvements in fat digestibility in all three. However, the oil from the extruded soybeans and the added oil in the soybean meal diet was digested to a significantly greater extent than that present in diets containing infra red cooked soybeans. It is possible that the oil in the infra red cooked soybeans would have been more available to the chick if the beans had been flaked after cooking, rather than ground. Flaking of heat-treated soybeans has been demonstrated to improve the availability of the oil (Carew et al., 1961). Flaking caused a disruption of the cellular structure, as did extrusion, allowing the chick to utilize the oil more effectively. Featherston and Rogler (1966) reported that flaking cracked raw beans resulted in an increase in the availability of oil from 67 to 99%. The results of these studies indicate that extrusion processing of unextracted soybeans resulted in a product which supported chick performance as well as commercial solvent extracted soybean meal. The performance of the chicks fed this product was improved by pelleting, possibly because of the light fluffy nature of the product. The infra red cooked soybeans were somewhat less effective in supporting chick gains than were the extruded soybeans or solvent extracted soybean meal, possibly due to less cell disruption, SUMMARY Two experiments have been conducted to evaluate two methods of processing unextracted soybeans for inclusion in broiler diets. Soybeans prepared by infra red cooking or extrusion were compared to solvent extracted soybean meal. All soybeans originated from the same lot of beans. Diets were formulated to contain the same amount of protein and oil with soybean oil added to the diet containing solvent extracted meal. Diets containing extruded soybeans supported chick performance equal or superior to feeds containing solvent extracted soybean meal with soybean oil added. Pelleting usually improved the value of the diets containing extruded soybeans, probably because of the fluffy nature of the product. Infra red cooked beans were usually inferior to solvent extracted soybean meal in mash diets, but of equal value in pelleted diets. It is postulated that flaking the infra red cooked beans rather than grinding them would increase their nutritional value by causing a greater rupture of the cells with a concommitant increase in digestibility of the oil. ACKNOWLEDGMENTS The authors would like to express their thanks to Farmland Industries, Kansas City, Missouri, for a grant-in-aid in support of this study. The generous assistance of Mr. A. I. Reisz of the Cooperative Processing Association, Van Buren, Arkansas; Mr. Harry Truax of Harry Truax and Sons, Mooresville, Indiana; and Mr. Oak B. Smith and La Von Wenger of the Wenger Mixer Manufacturing Company, Sabetha, Kansas, is gratefully acknowledged. REFERENCES Association of Official Agricultural Chemists, Official Methods of Analysis, 9th Ed., Washington, D.C.

6 1120 S. J. HULL, P. W. WALDROUP AND E. L. STEPHENSON Carew, L. B., Jr., F. W. Hill and M. C. Nesheim, The comparative value of ground unextracted soybeans and heated dehulled soybean flakes as a source of soybean oil and energy for the chicks. J. Am. Oil Chemists Soc. 38: Carew, L. B., Jr., and M. C. Nesheim, The effect of pelleting on the nutritional value of ground soybeans for the chick. Poultry Sci. 41: Duncan, D. B., 1955Multiple range and multiple f tests. Biometrics, 11: Featherston, W. R., and J. C. Rogler, A comparison of processing conditions of unex- INCREASED air movement facilitates an increase in convective heat exchange between the body surface and the surrounding air which is roughly proportional to the square root of the air velocity (Whittow, 1965). Thus, alleviation of some of the effects of high ambient temperatures on chickens has been related to increased air movement (Lee et al., 1945; Wilson et al., 1957), and the growth rates of broilers raised in diurnally cycling hot environments have been shown to increase approximately with the square root of the air velocity in the range from 6 to 150 m.p.m. (meters per minute) (Drury, 1966). In birds, as the ambient temperature increases, respiratory evaporation becomes more important as a means of heat loss. When the deep body temperature reaches about 42 C, panting occurs, with respiratory frequency and minute volume increasing but amplitude and tidal volume de- 1 Animal Husbandry Research Division. 2 Agricultural Engineering Research Division. tracted soybeans for utilization by the chick. Poultry Sci. 45: Schurch, A. F., The use of chromic oxide as an index for determination of the digestibility of a diet. J. Nutr. 41: Steel, R. G. D., and J. H. Torrie, Principles and Procedures of Statistics. McGraw-Hill Book Co., Inc. New York, N.Y. White, C. L., D. E. Greene, P. W. Waldroup and E. L. Stephenson, The use of unextracted soybeans for chicks. 1. Comparison of infrared cooked, autoclaved and extruded soybeans. Poultry Sci. 46: Physiological Responses of Chickens to Variations in Air Temperature and Velocity H. S. SIEGEL 1 AND L. N. DRURY 2 Southeast Poultry Research Laboratory, ARS-USDA, Athens, Georgia (Received for publication November 17, 1967) creasing (Whittow, 1965). Arterial pressure and vascular resistance are generally lowered (Whittow, 1965), and a rapid increase in environmental temperature results in an increase in heart rate (Linsley and Burger, 1964). Convection partially replaces respiratory evaporation as a means of heat loss when air velocities are increased up to 150 m.p.m. and the ambient temperature is below body temperature (Drury and Siegel, 1966). EXPERIMENTAL METHODS A detailed description of the air velocity facility has been published (Drury and Siegel, 1966). In general, it consists of six horizontal subchambers mounted over a main duct which is evacuated by a large fan. Air velocities are adjusted by perforated inlet plates and damper-controlled outlets. Velocities for each experimental series could not be precisely controlled, but approximate values determined with a hotwire anemometer and smoke are shown in Table 1. The entire unit is situated in a