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Focusing on commercial office real estate as both a manifestation of and a conduit of cross-border capital flows, this paper refers to the concepts of topology and topography in a theoretical and empirical exploration of contemporary ‘network economy’ spatial implications for the ‘polycentric urban region’ (PUR). A body of research has cast doubt on the normative European representation of the multi-centre PUR as a balanced, sustainable spatial development model. Yet, the model has continued to be propagated in European territorial strategy and has been influential internationally. Academic perspectives and qualitative evidence reviewed in the paper shed a light on mutual dependencies and recursive relations between network economy global structural processes, international office real estate investment practices mediated by city governments, and the spatial configuration of density. Commercial investment and city planning actor practices chime with urban agglomeration, spatial concentration and density. Quantitative evidence of associations between urban density and office real estate investment returns and capital flows is found. It is concluded that network economy topology, politics and the city are in a dialectical relationship with the PUR territorial governance agenda for spatially balanced regional development.

SUMMARY Eliminating the contamination of broiler carcasses by pathogens such as Salmonella that can cause human illness continues to be a tremendous challenge and concern for the poultry industry and government regulatory agencies. One source for the introduction of these pathogens in poultry production can be the feed. Extended heat conditioning of diets prior to pelleting combined with the addition of preservatives such as formaldehyde has proven effective in reducing the risk of Salmonella in poultry diets. However, there has been a concern that the addition of some forms of formaldehyde to diets subjected to extended heat treatment could decrease the metabolizable energy and amino acid availability of the diet. To partially address this question, the TMEn and digestible amino acid coefficients of a broiler starter diet treated with 0 (control) or 0.3% formaldehyde solution prior to heat treatment at 82°C for 4.5 min were determined. Cecectomized and intact adult Single Comb White Leghorn roosters were used for determining amino acid digestibility and TMEn, respectively. The addition of the formaldehyde compound did not affect either the TMEn or the digestible amino acid content of the diet, except for a marginal (less than 1%) decrease in arginine digestibility. These results indicate that the supplementation of poultry diets with formaldehyde solution prior to extended heat treatment to eliminate Salmonella contamination did not impact the nutritional value of these diets for poultry.

Prior research indicated that foot ash determinations were as robust as tibia bone ash determinations in reflecting the degree of bone mineralization in chicks at 14 d of age. In the current research, the relative effectiveness of the 2 procedures was evaluated in 21- and 42-day-old broilers while also evaluating a new dietary phytase supplement. In experiment 1, broilers were fed until 21 d of age a negative control diet with 0.24% available phosphorus, a positive control diet with 0.48% available phosphorus, or the negative control diet supplemented with 300, 500, 1,000, or 2,500 phytase units/kg diet. In experiment 2, broilers were fed until 42 d of age negative control diets having 0.275, 0.250, and 0.225 percent available dietary phosphorus in the starter, grower, and finisher periods, respectively, positive control diets having 0.475, 0.450, and 0.425 percent available dietary phosphorus in the starter, grower, and finisher periods, respectively, or the negative control diets supplemented with 500, 1,000, or 2,500 phytase units/kg diet. At 21 and 42 d of age, broilers fed diets supplemented with the 2 highest doses of phytase had foot and tibia ash values equal to those fed the positive control diet and higher than those fed the negative control diet. At 42 d of age, feed conversion and total breast meat yield values for the broilers fed the highest dose of phytase were superior to the values of the birds fed the positive control diet or the diet containing the lowest dose of phytase. The results indicate that adding levels of this new dietary phytase beyond what is necessary for normal bone mineralization enhances feed conversion and that dried foot and tibia bone ash determinations are both reliable in detecting differences in bone mineralization in 21- and 42-day-old broilers.

This paper gives an overview of economic assessments of the benefits of the control of 1-Methyl-2-pyrrolidone (NMP), an organic solvent, used in a number of sectors. Health risks associated with the manufacture of NMP include the risk of stillbirth and developmental retardation to pregnant workers, as well as a variety of chronic and acute effects, including respiratory effects.

This paper gives an overview of economic assessments of the benefits of the control of formaldehyde and reflects on developments in its risk management and regulation. Formaldehyde is used in the manufacture of resins, as a disinfectant and fixative and as a preservative in consumer products. Formaldehyde exposure can be harmful to human health.

SUMMARY Corn distillers dried grains with solubles (cDDGS) is a coproduct of the production of corn-based ethanol. Researchers have extensively studied the energy, protein, amino acid, and mineral composition of cDDGS; however, an evaluation of the vitamin content of the cDDGS has yet to be undertaken. Thus, this study was conducted to determine the vitamin composition of cDDGS. In addition, correlations between crude fat and vitamin E (α-tocopherol) of the 6 samples of cDDGS were determined. Crude fat and 8 representative vitamins [vitamin A, vitamin D, vitamin E (α-tocopherol), thiamine, riboflavin, biotin, pantothenic acid, and pyridoxine] of cDDGS samples were analyzed and the determined vitamin content was compared with the standard values of the NRC. The mean value of vitamin E (α-tocopherol) in the 6 cDDGS samples was 6.8 mg/kg. In addition, the mean values of thiamine and riboflavin in the 6 cDDGS samples were 7.7 and 2.3 mg/kg, respectively. The mean values of pyridoxine and pantothenic acid in the cDDGS samples were 3.5 and 10.9 mg/kg, respectively. On the basis of regression analysis, a positive relationship existed between crude fat and vitamin E (R = 0.6677, P = 0.1473) in the 6 samples. These findings add to the information available regarding the vitamin profile of cDDGS and will assist in decisions made on the use of cDDGS in poultry diets.

The use of new varieties of pearl millet (PM) as an alternative feed ingredient for poultry has gained increased interest due to the favorable nutritional characteristics of this grain. However, its incorporation into poultry feeds has been limited because commercial availability of PM in the United States is currently low and also because many feed mills lack the capacity to store more than 1 ground grain. Previous studies have demonstrated the advantages of the inclusion of moderate levels of whole grains in poultry feeds. A series of 3 experiments was conducted to investigate whether unground PM would be a satisfactory feed ingredient for laying hens. In Experiment 1, diets containing 5, 10, 20, 30, and 40% unground PM were fed. At the end of a 7-d feeding period, it was determined that the percentage of whole seed disappearance was equal to or greater than 98% at all levels of inclusion. No significant differences in whole seed disappearance were detected among treatments, indicating that laying hens have the capacity to break down whole PM seeds. In Experiment 2, diets containing 0 or 15% inclusion of either ground or unground PM were fed to laying hens for a 7-d feeding period. Starch digestibility of the diets was determined to be >97% for all treatments. Significantly greater starch digestibility was observed in the hens fed the 15% unground PM as compared with the hens receiving the ground PM diet. In Experiment 3, after a 4-wk feeding period, it was determined that the inclusion of 10% unground PM does not have a negative or positive effect on feed consumption or egg production. These results indicate that PM is a satisfactory feed ingredient for laying hens that can be included in the unground form at moderate levels.

Two of the most widely used phosphate sources for broiler diets are defluorinated tricalcium phosphate (DFP) and dicalcium phosphate (DCP). Reports in the literature have shown that the biological availability of P in DFP for broilers and laying hens is lower than that in DCP. If this difference in bioavailability is even greater in young chicks, it might preclude the inclusion of DFP in prestarter and possibly starter diets. To address this question, 2 experiments were conducted to compare the P bioavailability of DFP and DCP in young broilers during the prestarter (1 to 8 d) and starter (9 to 15 d) periods. In Experiment 1, the first 3 treatments contained DFP, DCP, or raw rock phosphate, which were added to the diets to meet 0.32% available P (AP). Additionally, in 3 other treatments that served as positive controls, K2 HPO4 was added to meet AP levels of 0.24, 0.32, and 0.40%. No significant difference was observed at 4, 8, and 15 d of age between the foot ash percentage of chickens fed the DFP and DCP diets, indicating that the biological availability of P in DFP was not significantly inferior to that of DCP. In Experiment 2, chick responses to 2 levels of either DFP or DCP, added to meet AP levels of 0.28 and 0.34%, were compared with those of chicks receiving K2 HPO4, which was added to meet 3 AP levels (0.22, 0.28, and 0.34%). Foot ash results at 6 and 15 d of age indicated that the P utilization of chickens fed diets containing DFP was not significantly different to that of chickens fed the DCP diets. The difference in P bioavailability between DFP and DCP at 6 or 15 d of age was not greater than 10%. These results indicate that DFP can be satisfactorily utilized by young chicks during the prestarter and starter period and do not support the view that DFP should be excluded from diets for young chickens.

Three studies were conducted to evaluate foot ash as an alternative method to quantify the degree of bone mineralization in broiler chicks. In Experiment 1, the objective was to evaluate whether degree of bone mineralization would be reflected by foot ash in broiler chickens at 14 d of age. Birds receiving 0.24, 0.32, or 0.40% of dietary available phosphorus (AP) demonstrated significant differences in foot ash (10.93, 13.46, and 15.45%, respectively). In Experiment 2, we determined that the time required for a foot sample to dry to a constant weight at 105°C was 48 h. In Experiment 3, the objectives were to compare the response of bone mineralization to dietary phosphorus levels as reflected by foot ash and tibia bone ash and to evaluate the effect of fat extraction on the determination of these parameters. Broiler chicks were fed graded levels of AP (0.25, 0.30, 0.35, and 0.40%) from 1 to 14 d of age. Significantly different responses between each dietary AP level could be detected by any method used. A significant linear response was observed between dietary AP and percentage of extracted or unextracted tibia or foot ash, with determination coefficients above 90% found for all 4 methods used. Results confirmed that the dietary phosphorus levels affected bone mineralization and that the degree of mineralization could reliably be reflected by foot ash. The assay was found to be as reliable as the tibia bone ash in reflecting degree of bone mineralization in chicks during the first 14 d of age. Fat extraction did not affect the reliability of either assay.

SUMMARY In recent years, policies encouraging the production of ethanol have stimulated an enormous increaseintheproduction ofdistillersdriedgrainswithsolubles(DDGS). Theformoftheingredient that is becoming increasingly available differs from that of previous decades in that it is derived almost entirely from corn and is dried under less severe conditions. Seventeen DDGS samples were obtained from 6 different plants in the midwestern United States from 2002 to 2004. Each sample was analyzed for TMEn, and 8 representative samples were analyzed for total and digestible amino acids (AA) by the precision-fed rooster assay using conventional or cecectomized Single Comb White Leghorn roosters, respectively. Color [lightness (L*), redness (a*), and yellowness (b*)] of each DDGS sample was measured with a Minolta Chroma Meter CR-300. The TMEn ranged from 2,490 to 3,190 kcal/kg (86% DM basis) and had a mean of 2,820 kcal/kg. Variation was noted among samples, presumably reflecting differences in the original corn composition, fermentation, and disposition of solubles. Considerable differences were observed among the true AAdigestibilitiesoftheDDGSsamples.Mostsamplesweregoldenincolor,andtrueAAdigestibility values were relatively consistent among these samples. The average total concentration and digestibility coefficients of several most limiting AA for the 8 DDGS samples were as follows: Lys, 0.71% (70); Met, 0.54% (87); cystine, 0.56% (74); Thr, 0.96% (75), Val, 1.33% (80), Ile, 0.97% (83); and Arg, 1.09% (84). Correlations were found among digestible Lys, Thr, Arg, His, and Trp and the yellowness (b*) and lightness (L*) of the DDGS samples. In general, DDGS samples that were more yellow and lighter in color had higher total and digestible AA levels. The variation in TMEn and AA digestibility observed among samples strongly indicated that confirmatory analyses should be conducted prior to using samples from a new supplier.

SUMMARY Two experiments were conducted with broiler chicks to determine the nutritive value of highoil sunflower meal (HO-SFM), a sunflower oil extraction by-product obtained through screw-press extraction and expanding processes with a proximate composition of 32% CP, 12% crude fiber, and 19% ether extract. In Experiment 1, the effects of a high level (46.4%) of HO-SFM on chick performance and gastrointestinal organs were tested. The objective of Experiment 2 was to determine if pelleting the feed could overcome the bulkiness resulting from inclusion of HO-SFM at a high level. The results of Experiment 1 indicated that addition of 46.4% HO-SFM to broiler starter diets significantly (P < 0.05) depressed body weight, feed intake, and gain but not feed conversion. Fat pad and liver lipid were again significantly (P < 0.05) decreased in the HO-SFM treatment. Impaired performance might have been due to the difference of the density of HOSFM diet (608 g/L) compared with the soybean meal control (723 g/L). When bulkiness was overcome by pelleting in Experiment 2, it was found that pelleting the feed significantly enhanced growth of broiler chicks compared with SFM or soybean meal mash diets. Liver weights and lipid content were again decreased in HO-SFM diets. The results of this study suggest that HO-SFM canbeused upto28%withoutadverse effectsonbroilerchicks.Further improvementwasobserved with pelleting. Liver weight and lipid content were consistently reduced by feeding HO-SFM.

Solvent-extracted peanut meal is receiving increased attention as a feed ingredient for poultry. Due to limited availability, levels of inclusion in US broiler diets are generally from 3 to 4%. Because the origin of nutrient values for peanut meal reported in standard tables of nutrient composition is unclear, a study was undertaken to document the nutrient composition of peanut meal samples currently available to the poultry industry. Seventeen samples of peanut meal were obtained during 2003 from commercial sources in the southeastern United States. Each sample was analyzed for proximate composition, TMEn, and mineral composition. Seven representative samples were analyzed for total and available amino acid contents. All values were adjusted to a 90% dry matter basis, this being representative of the meals evaluated in this study. Although considerable variation was noted between sources, a reasonable consistency was observed among samples from each of the 5 suppliers, presumably reflecting modest differences in processing procedure. Nitrogen-corrected metabolizable energy ranged from 2,273 to 3,009 kcal/kg with a mean of 2,664 kcal/kg, whereas CP ranged from 40.1 to 50.9% with a mean of 45.6%. Mean values for fat, fiber, and ash were 2.5, 8.3, and 5.0%, respectively. Total concentration and percentage availability, respectively, of several critical amino acids were: lysine, 1.54% (85); methionine, 0.52% (87); cystine, 0.64% (78); threonine, 1.17% (81); and arginine, 5.04% (90). Average levels of calcium, phosphorus, sodium, and potassium were 0.08, 0.57, 0.01, and 1.22%, respectively. The variation observed among samples strongly indicates that confirmatory analyses should be conducted prior to use of samples from a new supplier.

SUMMARY A major emphasis on ethanol production in the US has led to the construction of new ethanol plants and an increased production of distillers dried grains plus solubles (DDGS). In the past DDGS came largely from the beverage industry and consisted of several grains used during fermentation. Recently, a majority of the DDGS produced is from corn fermentation for ethanol production. Little research has been conducted to test the use of this new generation DDGS from modern ethanol plants in laying hen diets. Hy-line W-36 laying hens were used to test an elevated inclusion level of DDGS from modern ethanol plants that can be incorporated into layer diets. Hens were fed a commercial or low-density diet formulated to contain 0 or 15% DDGS for 25 to 43 wk of age. No differences were observed in the majority of parameters evaluated between hens fed 0% or 15% DDGS. However, there was a significant (P < 0.05) reduction in hen-day egg production through 35 wk of age when hens were fed the low-density diet with 15% DDGS. Hens fed the commercial diet with 15% DDGS had numerically lower egg production to 32 wk of age, but this was not statistically significant. Distillers dried grains plus solubles proved to be an acceptable feed ingredient for laying hen diets. A suggested maximal inclusion level of 10 to 12% DDGS, based on these data and previous research, may be used in commercial diets, but it is speculated that DDGS should be incorporated at lower levels in low-density diets.

Ether extract composition of poultry by-product meal (PBM) varies among feed-grade and pet food-grade sources. Because feed-grade PBM contains a wider variety of processing residues than pet food-grade PBM, it is presumed to be of lower fat quality (i.e., stability). This potential difference in fat quality, or stability, between PBM sources can be accentuated by high environmental temperatures. A total of 46 PBM samples (25 feed-grade and 21 pet food-grade) were collected from commercial feed mills located in the southeastern US within 60-d intervals during the winter and summer months. For samples from winter collection, feed-grade PBM had lower fat stability than pet food-grade PBM. Conversely, pet food-grade PBM samples received in the summer were characterized as having poor stability, and the amount of analyzed residual antioxidant concentration in pet food-grade PBM was half that found in the feed-grade PBM samples. Seasonal effects appeared to be related to the extent of fat oxidation. In general, samples obtained in the summer had poor stability when compared with those collected during the winter, regardless of source. These results confirmed that fat in PBM requires an adequate amount of antioxidant protection, even when meals are derived from prime offal components.

Previous research indicates that performance and carcass yields of broilers fed diets containing up to 50% ground pearl millet were equivalent or better than those of broilers fed typical cornsoybean diets. As production of new cultivars of pearl millet increases, availability of grain may be limited and seasonal. Therefore, inclusion of lower levels of millet as whole seeds in broiler diets may be more suitable. To determine the feasibility of including whole millet seeds in broiler diets, 3 experiments were conducted. In 2 battery studies broilers were fed diets containing 0, 5, 10, 15, and 20% whole millet. Disappearance of whole millet was greater than 95% for all treatments as determined by the general absence of millet seed in the excreta. Performance of broilers from 1 to 15 d was unaffected by the inclusion of whole millet in the diets, but gizzard size increased in birds fed diets containing 10% or more pearl millet. In a final experiment the performance and carcass yields of broilers fed diets containing 5 or 10% whole millet from 1 to 42 d of age were equivalent to those fed typical corn-soybean meal diets. These results indicate that whole seeds of millet can be successfully incorporated into broiler diets without compromising bird performance.

SUMMARY Due to its low nutrient density, cottonseed meal (CSM) may be a potential alternative feed ingredient for soybean meal (SBM) in broiler breeder pullet diets to improve flock BW uniformity. A major concern when utilizing CSM in poultry diets, however, is the presence of gossypol. It was determined in an initial experiment that when broiler breeder hens are fed a diet containing CSM, gossypol accumulates in the liver. When CSM is removed from the diet, however, hepatic gossypol levels dissipate within a few weeks. In a subsequent study, in order to achieve the breeder guideline ideal weight, broiler breeder pullets reared with a diet containing CSM from 2 to 18 wk of age had to be fed a larger amount than birds consuming a standard SBM diet. The CV of bird weight was significantly lower during the rearing period for birds reared with the corn and CSM diet. This difference in uniformity was maintained as the hens entered the breeding period. Egg weight, hatchability, and fertility were equivalent for hens reared with a diet containing CSM and those reared with a standard diet throughout the growing period. The results suggest that broiler breeder pullets reared on a diet containing CSM as the major protein source have improved flock BW uniformity and normal subsequent reproductive performance.

Pet-food manufacturers have specified to renderers the need for poultry by-product meal (PBM) to be manufactured without lower quality by-product fractions, such as feathers and heads, leading to a higher protein product than conventional feed-grade PBM. One result is that nutritionists are faced with greater nutrient variation among PBM sources. Thirty-six PBM samples (26 = feed grade and 10 = pet-food grade) were collected from commercial feed mills during a 3-mo period to assess nutrient composition and its variation. Pet-food-grade PBM had higher protein, less ash, and lower calcium than feed-grade PBM. Amino acid analyses indicated the pet-food-grade PBM had higher lysine and methionine, and the amino acids in pet-food-grade PBM exhibited higher digestibility compared with those in the feed-grade samples. Nutrient variability was more pronounced in the feed-grade PBM.

Production of distillers dried grains with solubles (DDGS) is expected to double within the next few years and substantially increase the quantities of DDGS available to the feed industry. To properly evaluate the potential role of this ingredient, a complete nutritional profile, including mineral composition, must be available to feed formulators. Twelve samples of commercially prepared DDGS were obtained from the northern central United States and analyzed for mineral composition. Analysis indicated an enormous range of 0.09 to 0.44% with an average value of 0.23% in sodium content. The average composition of many of the other minerals (except calcium and sulfur) agreed with projected values based on a 3-fold increase of the levels found in yellow corn grain.

Widespread cultivation of pearl millet for grain production in parts of the United States has been limited due to its susceptibility to rust disease. Over the last 3 yr, grain from a recently developed rust-resistant hybrid of pearl millet was evaluated for its potential use in poultry broiler diets. The evaluated grain from each year had a comparable TMEn value (3,300 to 3,448 kcal/kg) and higher protein content (12 to 14%) than corn. In two battery studies (2 to 16 d of age) and two floor pen experiments (1 to 42 d of age) varying levels of pearl millet replaced yellow corn and a portion of soybean meal in isocaloric and isonitrogenous diets. The performance and carcass yield of broilers fed diets containing up to 50% pearl millet were equivalent or better than those of broilers fed typical corn-soybean diets. The results clearly indicate that this new hybrid of pearl millet could be a successful alternative grain for poultry production. Because pearl millet can be successfully cultivated in regions where corn production is marginal, this grain may prove to be economically beneficial to the grain and poultry producers in such areas.

This paper reviews the characteristics of cassava root meal and the problems and considerations involved when using it in poultry diets. A high starch content and a low percentage of protein and amino acids are cassava's main nutritional traits. However, when cassava root meal is used in poultry diets, other factors should be taken into consideration, including cyanogenic content, high level of potassium and silica, lack of carotenoids, and dustiness. Cassava's normal rate of inclusion in poultry diets in the European Union is about 25%. The inclusion of cassava root meal in poultry feeds will depend on the price and availability of energy and protein sources, synthetic amino acids, and pigments.

Using a flotation/sedimentation technique, an assay was developed to provide a rapid estimate of the ash, calcium (Ca), and phosphorus (P) content of meat and bone meal (MBM). Thirty samples of commercially rendered MBM were assayed for Ca, P, and ash by standard procedures. Volume of bone was determined by sedimentation. When MBM is mixed with chloroform, the bone fraction settles to the bottom of a graduated cylinder, the meat portion floats to the surface, and fat is dissolved. Performing this procedure under standardized conditions (20 g MBM mixed into 50 mL chloroform in a 100-mL graduated cylinder) resulted in a highly significant (P Prediction equations to estimate Ca, P, or ash contents of MBM samples are: % Ca = 0.60 + 0.92 (mL bone) R2 + .84 % P = 0.54 + 0.43 (mL bone), R2 + .85 % ash = 6.87 + 2.21 (mL bone), R2 = .83

Short term studies were conducted with older laying hens to evaluate the efficacy of Eggshell #49 (Alltech, Inc., Nicholasville, KY) in improving shell quality. The product is a combination of several trace mineral proteinates, most prominently manganese and zinc. Both these trace minerals are essential for proper eggshell formation. Results of these studies failed to show a positive effect of the test product on eggshell quality, as measured by specific gravity. It should be noted, however, that levels of manganese and zinc in the basal diet contained ample margins of safety. Whether the test product would have given positive results with marginal levels of inorganic trace mineral supplementation was not addressed in these studies.

Commodities such as food and manufactured goods, particularly those that rely on land and water, are increasingly recognised as being potentially sensitive to climate change on a global scale, suggesting that the international dimension is critical when considering future supply susceptibilities of import-dependent countries, such as the UK. We estimated embodied water imported to the UK for 25 economically significant and climate-sensitive sub-sectors, then explored the current and future susceptibilities of these sub-sectors under climate change. In 2010, these products represented 31% of total UK imports by value (US$) and 12.8 billion m of embodied water. Of this total, rice, bovine and pig meat production, plastics and paper account for ~60% of the volume of water embodied in the import categories considered. By combining product-based water volume estimates with economic and climate model information, we show how the UK could be increasingly susceptible to loss of these water supplements in the future. In doing so, we provide an indication of how countries that depend upon climate-sensitive imported resources can account for these dependencies in a systematic way. For example, international adaptation and development funding may be targeted to the securing of supplies from existing exporting countries, or trade relations may be encouraged with potential new suppliers who are likely to be less resource-constrained. © Inter-Research 2014.

Waxy corn sometimes becomes available to the feed industry when its supply exceeds the demand of the wet milling industry. Several research papers in the past have evaluated the feeding value and/or metabolizable energy (ME) of waxy as opposed to normal corn. Unfortunately, several artifacts present in most of these studies complicate an interpretation of published data. True metabolizable energy (TMEn) assays were conducted on three sets of normal and waxy versions of the same corn hybrids. It was confirmed that corn hybrids vary in metabolizable energy. The TMEn of the three normal hybrids used in this study ranged from 3883 to 4024 kcal/kg (dry basis). However, results do not indicate a difference in TMEn of waxy vs. normal corn of the same hybrid. Thus, when formulating poultry rations with waxy corn, there is no reason to make any adjustment in metabolizable energy unless the specific hybrid is known to be low or high in caloric or protein value.

To obtain information on the nutrient content and variability of spent hen meal, we examined meal produced form end-of-lay hens by three Renderers using conventional rendering procedures. Meal from three Renderers varied considerably in nutrient content. Amino acid content as percentage of sample varied among Renderers, but when expressed as percentage of protein less variability was observed, especially for amino acids of practical concern. Although amino acid digestibility varied somewhat among sources, overall agreement was good; values in the present study should provide guidelines for estimating digestible amino acid content of spent hen meals produced by conventional rendering. Mean amino acid digestibility among sources was not directly associated with digestibility in 0.2 or 0.002% pepsin. Nutrient content of samples produced by a commercial renderer over a 27-wk period appeared reasonably consistent

Assaying meat and bone meal as separate fractions rather than complete meal yields substantially higher metabolizable energy (ME). Past research has indicated that elevated mineral levels in meat and bone meal depress the metabolizable energy of this ingredient under assay conditions. Samples of meat and bone meal from port and from beef origin were separated into “bone” and “meat + fat” fractions by chloroform flotation. When meat + fat fractions were assayed and an ME value estimated for residual protein and fat in the bone fractions, the energy for samples of beef and of port meat and bone meals used in this study were 2449 kcal/kg (1115 kcal/lb) and 2847 kcal/kg (1275 kcal/lb, respectively (94% DM).

Wide variations in amino acid composition and proximate components between pet food-grade and feed-grade poultry by-product meals (PBM) have been reported from this laboratory. Four samples of pet food-grade and feed-grade PBM were evaluated for TMEn and proximate composition. The TMEn values for feed-grade PBM ranged from 2,775 to 3,555 kcal/kg, whereas pet food-grade PBM varied from 3,316 to 3,401 kcal/kg.

Manufacturers of distillers dried grains with solubles (DDGS) are changing practices to extract corn oil from DDGS in the process of ethanol production. The resulting product is called low-oil DDGS (LO-DDGS) and may be included in broiler diets. Two LO-DDGS and one unextracted DDGS were used in a broiler performance trial to determine maximum levels of inclusion without detrimental effects. Corn- and soybean meal-based mash diets were used with different DDGS samples included at 10 or 20%. Six hundred thirty Cobb 500 male by-product chicks were randomly assigned to 6 replicate pens containing 15 chicks each and fed diets from 0 to 18 d of age. There was a significant interaction between source and level on BW at d 11 and 18 when 10 and 20% of LO-DDGS was included compared with the control group. There was also a significant effect of source and level interaction on BW at d 18 (P < 0.05). Feed efficiency from d 0 to 18 was improved when 10% LO-DDGS was used compared with 20% inclusion. Abdominal fat pad weights were higher when LO-DDGS samples were included at 10 or 20% compared with the control group. There was a significant effect of DDGS source and level on fat pad weights (P < 0.05). Producers may achieve an increase in performance when including 10% LO-DDGS in broiler diets. Up to 20% inclusion levels may have no detrimental effects on performance parameters compared with a standard corn-soybean diet.

The composotion of wheat milling by-products varies markedly in different geographic regions among suppliers. In this study, the determined true metabolizable energy (TMEn) of 15 samples of wheat by-products, along with proximate composition and NDF, were investigated to develop prediction equations for estimating energy values. Both crude fiber and NDF were found to be useful indicatorsof of the TMEn of wheat by-products.

The development of selected biogenic amines, including phenethylamine, cadaverine, histamine, tyramine, spermidine, spermine, putrescine, tryptamine, 5-hydroxy-tryptamine, and 3-hydroxy-tyramine, were measured over 70 days of lactic acid bacterial fermentation of whole poultry carcasses. The development of ammonia nitrogen and changes in the concentration of amino acids, including phenylalanine, lysine, histidine, tyrosine, methionine, spermidine, and spermine, were also evaluated. The concentration of amino acids phenylalanine, lysine, and tyrosine decreased significantly during the 70-day fermentation period. The concentration of the following biogenic amines increased during bacterial fermentation: phenethylamine, cadaverine, histamine, tyramine, putrescine, and tryptamine.

Oilseed meals frequently constitute between 20 and 30% of poultry and livestock diets and contribute more than half of total protein. Thus, factors relating to protein quality and amino acid composition are of prime concern in assessing oilseed meal quality. Total protein content can be affected by factors such as cultivar, growing conditions, and levels of fiber and moisture. Of equal concern is the quality of protein in oilseed meals as influenced by degree of processing. Overheating during the drying/desolventizing phase can impair lysine digestibility. An overall quality control program for oilseeds must be based on the measurement of variations in protein content and, in addition, degree of processing.

By-products of the processing of tilapia are beginning to appear as feed ingredients. Eight samples were obtained and evaluated for nutrient content so as to provide the nutritionist with a baseline of information with which to consider possible use of this ingredient. At the present time, there is considerable variation in the composition of tilapia meals from different sources. Nutrient composition ranged from: CP, 52.5 to 57.8%; TMEn, 2,374 to 3,269 kcal/kg; and Ca, 5.2 to 10.6%. As significant variation was noted in levels of most nutrients, confirmatory analysis on specific samples is recommended prior to general use in formulation.

Six battery experiments determined the effect of feeding raw soybeans (RSB) in corn-soybean diets on coccidiosis in broiler chickens. The experimental design represents a 2 × 3 factorial arrangement of treatments with three dietary levels of incorporation of RSB (0, 50, and 100%), and chickens either infected or uninfected. The coccidial species tested singularly were Eimeria acervulina, Eimeria maxima, Eimeria necatrix, Eimeria brunetti, and Eimeria tenella. With all species of Eimeria a significant diet by infection interaction demonstrated with a stepwise increase in weight gain and reduction in lesion scores with increasing levels of raw soybeans. To cause the pancreas to become hypertrophied and hyperfunctional, the 100% RSB diet was fed for an extended period. The experimental design represents a 2 × 3 factorial arrangement of treatments with three feeding regimens [Treatment A: 0% RSB (0 d to termination), Treatment B: (0% RSB: 0 12 d then 100% RSB 12 d to termination), and Treatment C: (100% 0 d to termination)] and chickens either infected (E. tenella) or uninfected. There was significant difference for weight gain between uninfected and infected chicks of Treatments A and C but this difference was absent for Treatment B. Coccidiosis was not reduced by continuously feeding 100% RSB (Treatment C).

A series of studies was conducted to determine the relative metabolizable energy content of whole corn kernels, broken corn (BC), and foreign material (FM). Samples of yellow corn were obtained from eight different trains and separated into the three fractions which were assayed for proximate composition and nitrogen corrected true metabolizable energy. On average, whole kernels contained 3439 kcal/kg (86% dry matter), BC 2.5% less, and FM 11% less than intact kernels. Considerable variation was noted in the energy of the FM fraction. The relatively modest reduction in energy noted for the BC and FM fractions does not reflect the possible risks associated with insect and mod infestation of these fractions.

Twenty-six yellow corn samples of varying bushel weight, free of observable insect or mold damage, were evaluated for metabolizable energy and protein content. A slight but significant positive correlation was observed between bushel weight and true metabolizable energy (TMEn) of corn samples, which increased by an average of 6.9 kcal/kg (3.1 kcal/lb) for each lb increase in bushel weight. However, considerable variation in the TMEn content of samples of similar weight suggests that this observation has limited practical significance for samples above 50 lbs/bushel. There was no significant effect of bushel weight on crude protein content.

Reduced bone strength was thought to be a contributing factor to a high incidence of rib breakage noted at a commercial broiler processing plant. In two studies, percent bone ash determinations were made on birds exhibiting either intact or broken ribs. No indication was found that reduced bone strength was associated with the broken ribs, which clarified the overall review of possible causes. The approach employed in this study might be considered in similar situations where bone weakness is suspected as a single or contributing cause of a field problem.

By-products of the processing of catfish have become available as a feed ingredient. Five samples were obtained and evaluated for nutrient content so as to provide the nutritionist with a baseline of information with which to consider possible use of this ingredient. The most unique nutritional features of catfish meal are high levels of protein (60%) combined with calcium (8%) and phosphorus (4.2%). Essential amino acids as percentages of crude protein tend to be somewhat lower than other fish meals. Average TMEn was 2,773 kcal/kg (94% DM).

Feather meal has a higher energy content than indicated by U. S. tables of nutrient composition. Fifteen samples of hydrolyzed poultry feathers obtained from commercial channels were evaluated for proximate composition and true metabolizable energy (TMEN) content. The TMEN of feather meal samples ranged from 3092 to 3996 kcal/kg (1406 to 1816kcal/lb). These values were found to closely reflect the fat content of the individual samples, which ranged from 1.8% to 12%. The TMEN of feather meal from turkeys was similar to that of chickens with comparable fat levels. Metabolizable energy can be estimated from the fat content of well processed feather meals by the following equations (R2 = . 81): TMEN (Kcal/Lb) = 1301 + 35(%Fat) TMEN(Kcal/Kg) = 2862 + 77(% Fat)

Two experiments were conducted to investigate whether the availability of synthetic lysine is reduced in pelleted diets containing dried bakery product (DBP). Free sugars in DBP might promote lysine destruction through the Mailard Reaction. However, neither in a chick growth study nor by chemical analysis was there any indication of reduced lysine availability under such conditions. The hypothesis that pelleting may lead to lysine destruction in diets with dried bakery product is not supported by these data.

Gossypol is a toxic polyphenolic compound produced by the pigment glands of the cotton plant. The free gossypol content of cottonseed meal (CSM) is commonly determined by the American Oil Chemists’ Society (AOCS) wet chemistry method. The AOCS method, however, laboratory-intensive, time-consuming, and therefore, not practical for quick field analyses. To determine if the free gossypol content of CSM could be predicted by near infrared reflectance spectroscopy (NIRS), CSM samples were collected from all over the world. All CSM samples were ground and a portion of each analyzed for free gossypol by the AOCS procedure (reference data) and by NIRS (reflectance data). Both reflectance and reference data were combined in calibration. The coefficient of determination (r2) and standard error of prediction (SEP) were used to assess the calibration accuracy. The r2 was 0.728, and the SEP was 0.034 for the initial calibration that included samples from all over the world. However, the r2 and SEP improved to 0.921 and 0.014, respectively, if the calibration was made using CSM samples only from the United States. These results indicate that a general prediction equation can be developed to predict the free gossypol content of CSM by NIRS. From a practical standpoint, NIRS technology provides a method for quickly assessing whether a particular batch of CSM has a free gossypol content low enough to be suitable for use in poultry diets. This research was supported in part by grant 05-635GA from the Georgian Cotton Commission, Perry, GA

Three experiments were conducted to compare urease activity (UA), orange G-binding capacity (OGBC), and protein solubility (PS) in a potassium-hydroxide solution of soybean meal (SBM) as indicators of overprocessing. In two additional experiments, amino-acid supplementation was employed in an attempt to overcome the growth depression associated with overheating SBM. Subsamples of commercially prepared lots of dehulled SBM were heated for varying periods of time in an autoclave at 121 C. In Experiments 1, 2, and 3, UA dropped to zero (pH change) after approximately 10 min of cooking. The assay was unable to differentiate between meals that were heated for longer periods. The OGBC of SBM was decreased by autoclaving. However, the narrow range of the orange G values that corresponded to degrees of heat treatment indicated that this test may be of limited value in identifying overprocessed SBM. By contrast, PS values decreased with each increase of autoclaving time, and did not approach zero even with 80 min of heating. Adding .2 % lysine either singly or in combination with .2% arginine or. 1% methionine, or both, totally overcame the growth depression due to overprocessing. The weight gains and feed conversions of broiler chicks were negatively correlated with autoclaving times in excess of 10 minutes. In all experiments, PS values more closely reflected the impaired chick performance from overheated SBM than UA or OGBC. The PS values below 70% suggested overprocessed SBM.

Twenty-six samples of dried bakery product (DBP) were obtained from commercial sources and were evaluated for their proximate composition and TMEn content. Among the samples, marked variations were noted in ash, fiber, ether extract, and TMEn content. An equation to predict the TMEn content from the proximate composition was developed: TMEn (kcal/kg) = 3.9 + .02 × ether extract – .09 × crude fiber .03 × ash (R2 = .80). Ten additional samples of DBP were evaluated for proximate composition and TMEn in order to test the prediction equation. The error obtained when estimating the TMEn content from the prediction equation (4.1%) was substantially less than that obtained when assuming an average value based on Samples 1 to 36 (6.8%). The final prediction equation, derived from Samples 1 to 36, was: TMEn (kcal/g) = 4.34 –.10 × crude fiber – .04 × ash – .03 × protein + .01 × ether extract (R2 = .78). The mean errors based on the initial and final equations were 2.91 and 2.65%, respectively. Both compare favorably with the residual error of 5.78% obtained when using the average value of 3.63 kcal/g. All values given are expressed on the basis of 90% dry matter.

Two experiments were conducted to compare standardized ileal amino acid (AA) digestibility in 7- and 21-d-old chicks and true AA digestibility as determined by the precision-fed cecectomized rooster assay for several ingredients used in poultry feeds. Diets were formulated to contain soybean meal, cottonseed meal, poultry by-product meal, and fish meal in experiment 1 and corn, wheat, soybean meal, poultry by-product meal, feather meal, and fish meal in experiment 2 as the sole sources of protein. Celite, used as an indigestible marker, was added at 1.5% of the diet. The test diets were fed ad libitum to broiler chicks from 0 to 7 d of age in experiment 1 and from 4 to 7 and 17 to 21 d of age in experiment 2. Ileal digesta samples were collected after euthanizing the birds at 7 d of age in experiment 1 and at 7 and 21 d of age in experiment 2. Additionally, cecectomized, Single-Comb White Leghorn roosters were used for crop intubation of the test diets for determination of true AA digestibility. In experiment 1, AA digestibility of all ingredients tested was significantly lower at 7 d of age than when determined by the rooster assay. In experiment 2, no differences were detected between AA digestibility at 7 or 21 d of age in the chick assay for the majority of the indispensable AA. However, the AA digestibility coefficients obtained by the chick assay at 7 d and, in some cases, at 21 d of age, were significantly lower than those obtained by the rooster assay. In conclusion, there were differences in the AA digestibility coefficients obtained through the chick and the rooster assays. Such discrepancies could be associated with an age effect or the methodological differences between both methods.

Two experiments were conducted to evaluate the use of distillers dried grains with solubles (DDGS) from modern ethanol plants in broiler diets. Experiment 1 was a 2 x 2 factorial experiment with diets containing 2 levels of DDGS (0 and 15%) and 2 diet densities (high and low). The high- and low-density diets were formulated to contain 22% CP and 3,050 kcal MEn/kg and 20% CP and 3,000 kcal MEn/kg, respectively. Eight pens of 6 chicks were fed an experimental diet from 0 to 18 d of age. Weight gain and feed efficiency (gain:feed ratio) of the chicks receiving the high-density diets were (P0.05) better than those of chicks fed the low-density diets. However, within the 2 density levels there was no difference in performance of chicks fed diets with 0 or 15% DDGS. In experiment 2, 6 replications of 50 chicks were fed 1 of 4 dietary treatments for 42 d. The diets were formulated to be isocaloric and isonitrogenous and contained 0, 6, 12, or 18% DDGS. There was no significant difference in performance or carcass yield throughout the 42 d experiment except for a depression in BW gain and feed conversion when chicks were fed diets with 18% DDGS in the starter period. These studies indicate that DDGS from modern ethanol plants is an acceptable feed ingredient for broiler diets and can be safely used at 6% in the starter period and 12 to 15% in the grower and finisher periods.

Twenty-two samples of poultry offal meal were evaluated for proximate composition and nitrogen corrected true metabolizable energy (TMEn) content. Wide variations were noted in fat, ash, protein, and TMEn content, with the latter values ranging from 3626 kcal/kg (1648 kcal/lb) to 5247 kcal/kg (2385 kcal/lb). A prediction equation to estimate TMEn was developed based on fat and ash content.

Tuna meal is distinct from many other types of fish meal in that fillets have previously been removed for human consumption. Three samples of tuna meal were found to have less protein but a proportionately higher mineral content than reference values for meals made from whole fish. The metabolizable energy content of tuna meal was lower than values reported for most common types of fish meal.

In five experiments an attempt was made to reduce the effects of heat stress on broiler chicks by lowering the heat increment of the diet. Percent of energy derived from fat was increased by replacing corn starch with fat, calorie for calorie, which reduced formula weight and increased diet density. In one treatment total protein level was reduced also while maintaining adequate essential amino acid levels. The effect of caloric and nutrient density was separated from that of “percent fat calories” by the use of a non-nutrient filler in one diet. Experimental rations were fed to male broiler chicks from 4 to 7 weeks of age in hot (31.1 ± 2 C) vs. cool (20.0 ± 2 C) controlled temperature chambers. In all experiments, metabolizable energy (ME) intake was increased when fat calories replaced carbohydrate (CHO) calories. In the high fat treatments, chicks gained significantly more body weight than did the high CHO control groups. This increase, however, was similar at both temperatures, indicating that the beneficial effect of dietary fat was independent of temperature. A portion of the improvement in ME intake and weight gains resulting from increased ratio of fat to non-fat calories was retained when diet density was equalized. Heat production measured by energy balance studies was numerically lower in chicks fed diets with the high ratio of fat to non-fat calories.