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Feed Ingredients (feed + ingredient)
Kinds of Feed Ingredients Selected AbstractsEvaluation of Glycerol from Biodiesel Production as a Feed Ingredient for Channel Catfish, Ictalurus punctatusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2010Menghe H. Li Glycerol is the main by-product of biodiesel production from vegetable oils and animal fats. It has been evaluated as an energy source for several farm animals. A study was conducted to examine the effects of various levels of glycerol in channel catfish, Ictalurus punctatus, diets. Fish with mean initial weight of 6.8 ± 0.1 g were stocked in 110-L flow-through aquaria and fed practical diets containing 0, 5, 10, 15, and 20% glycerol for 9 wk. There were no significant differences in feed consumption, weight gain, feed efficiency ratio, and liver lipid level among fish fed diets containing 0, 5, and 10% glycerol. However, fish fed diets containing 15 and 20% glycerol had reduced weight gain, feed efficiency, and liver lipid content. Survival was not affected by dietary glycerol levels. Blood glucose level was significantly higher in fish fed 5% glycerol than fish fed other diets. Fillet protein and fat generally decreased and fillet moisture increased as dietary glycerol level increased. It appears that channel catfish can utilize about 10% glycerol in the diet without adverse effects on feed consumption, weight gain, feed efficiency ratio, hemoglobin, hepatosomatic index, and liver lipid. [source] Apparent Digestibility Coefficients of Various Feed Ingredients for Grouper Epinephelus coioidesJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2004Heizhao Lin Apparent digestibility coefficients (ADC) of dry matter, crude protein, lipid, gross energy, amino acids, and fatty acids in white fish meal, brown fish meal, soybean meal, peanut meal, and yeast were determined for grouper Epinephelus coioides. Apparent digestibility was determined using a reference diet with 0.5% chromic oxide indicator and test diets that contained 70% reference diet and 30% of the feed ingredient being evaluated. The fish, averaging 12.0 g, were held in 250-L tanks at a density of 30 fish per tank. Feces were collected from three replicate groups-of fish. Apparent dry matter digestibility of ingredients was 78.85 ± 2.43, 79.11 ± 0.61, 69.85 ± 3.60, 73.67 ± 2.30 and 57.70 ± 4.69% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. Apparent gross energy digestibility of ingredients was 93.27 ± 2.90, 89.48 ± 1.78, 70.52 ± 4.01, 73.13 ± 2.41 and 51.67 ± 2.01% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. Apparent protein digestibility of ingredients was 89.82 ± 1.24, 87.34 ± 1.25, 83.97 ± 1.92, 80.79 ± 1.95, and 61.14 ± 0.54% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. White fish meal and brown fish meal showed higher protein digestibility among ingredients tested (P ± 0.01). Lipid digestibility of ingredients was high (90.66-94.48%) and not significantly different except for yeast. Amino acid availability values for test ingredients were similar to values of protein digestibility. Amino acid availability values of white fish meal and brown fish meal were higher than other ingredients. Fatty acid availability values for test ingredients were similar to values of lipid digestibility. In general, the digestibility of most fatty acids was over 80% in all ingredients, except for 14:0 in yeast and 18:0 in peanut meal, PUFA + HUFA > MUFA > SFA. Longer-chain saturated fatty acids were less digestibility, except for 14:0, with digestibilities diminishing as fatty acid chain length increased. Apparent digestibility of dry matter, crude protein, lipid, gross energy, amino acids, and fatty acids in yeast was the lowest among the ingredients. [source] A SURVEY OF THE PREVALENCE OF SALMONELLA AND OTHER ENTERIC PATHOGENS IN A COMMERCIAL POULTRY FEED MILLJOURNAL OF FOOD SAFETY, Issue 1 2003PAUL WHYTE ABSTRACT A study of the prevalences of Salmonella, Listeria and thermophilic campylobacters in a dedicated commercial poultry feed mill was undertaken. Salmonella was frequently recovered in samples taken in the preheat and postheat treatment areas of the mill with the overall percentage of samples positive found to be 18.8% and 22.6%, respectively. Feed ingredients and dust collected in the preheat treatment locations within the mill were frequently contaminated with Salmonella (11.8% and 33.3% of samples, respectively). High prevalences of Salmonella were also detected in dust samples (24.2%) obtained from the postheat treatment area of the mill and from feed delivery vehicles (57.1%). Listeria was also recovered from samples at pre- and postheat treatment areas within the mill with overall isolation rates of 14.1% and 18.5% observed, respectively. The most frequently observed species of Listeria recovered from samples in both areas within the mill was L. innocua, L. monocytogenes, L. grayi and L. welshimeri. No thermophilic campylobacters were recovered from any of the samples analyzed in the current study. [source] Effects of extrusion processing of feed ingredients on apparent digestibility coefficients of nutrients for rainbow trout (Oncorhynchus mykiss)AQUACULTURE NUTRITION, Issue 2 2003Zongjia J. Cheng Abstract An experiment was conducted to evaluate the effects of extrusion processing on apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude fat, energy and minerals in soya bean meal (SBM), barley, corn gluten meal and whole wheat, using rainbow trout Oncorhynchus mykiss as the test species. In addition, availabilities of amino acids were also determined in SBM. Feed ingredients were preconditioned at 89,93 °C and then extruded using a Wenger X-85 extruder. Nonextruded ingredients were used as is, meaning that they were not preconditioned. The extruded and nonextruded ingredients were mixed with a casein,gelatin reference diet at 3 : 7 ratio prior to determination of ADC values. A total of 135 trout (initial mean body weight 223.4 ± 12.7 g) were stocked into nine 140-L fibreglass digestibility tanks with 15 fish per tank. Individual tanks were assigned randomly to each of eight diets made from the four ingredients (extruded and nonextruded) plus the reference diet. After faeces were collected in the first week, the diets were switched among tanks, and faeces were collected again after 5-day acclimation period in the second week. Yttrium oxide was used as the inert marker. Results showed that extrusion processing significantly improved ADCs of dry matter, crude fat and gross energy, and reduced ADCs of crude protein, phosphorus, copper, iron and zinc. Results also showed that the effects of extrusion processing on chemical composition and ADCs of nutrients depended on the ingredients. It is recommended that trace minerals such as copper, iron and zinc be supplemented by an additional 10,20% when rainbow trout diets are extruded because of their reduced bioavailability in plant meal-based feed ingredients. [source] Taurine concentrations in animal feed ingredients; cooking influences taurine contentJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 7-8 2003A. R. Spitze Summary The aim of this study was to determine the taurine content in a variety of animal feeds. There is very little information on the taurine content of ingredients used in home-prepared diets for dogs and cats, and foods fed to wild animals in captivity. This study reports the taurine content of both common and alternative feed ingredients, and compares taurine loss as a result of different methods of food preparation. Foods were selected based on their use in commercial and home-prepared diets. Animal muscle tissue, particularly marine, contained high taurine concentrations. Plant products contained either low or undetectable amounts of taurine. The amount of taurine that remained in a feed ingredient after cooking depended upon the method of food preparation. When an ingredient was constantly surrounded by water during the cooking process, such as in boiling or basting, more taurine was lost. Food preparation methods that minimized water loss, such as baking or frying, had higher rates of taurine retention. [source] Estimation of metabolisable energy content of date pit and its effect on lipid and protein oxidation in broiler chicksJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2009Mojtaba Zaghari Abstract BACKGROUND: Two experiments were conducted to evaluate date pit as a feed ingredient in broiler chick diets. In the first experiment, apparent metabolisable energy (AME) of date pit was determined using 72 Ross (308) broiler chicks. Broiler chicks received experimental diets from 25 to 30 days of age. Two diets were fed: diet 1, basal diet and diet 2, 60% basal diet + 40% date pit. Date pit ileal AMEn was estimated to be 704 kcal kg,1. The second study was conducted to evaluate the AMEn value obtained and also the effectiveness of using a commercial multi-enzyme in diets containing date pit. Diets with three levels of date pit (10, 20 and 30% date pit) with or without enzyme supplementation were fed to broiler chicks from day old to 42 days of age. RESULTS: Chicks receiving different levels of dietary date pit had comparable body weight to those fed on corn,soybean meal diet. Both date pit levels and enzyme supplementation had a significant effect on feed conversion ratio. Plasma total antioxidant levels of positive control were significantly lower than the experimental diets. CONCLUSION: Results obtained in our study suggested that date pit could be used as a feed ingredient in the diet of broiler chicks without any negative effect on performance. Furthermore, date pit may have beneficial effects on plasma antioxidant status in broiler chicks. Copyright © 2009 Society of Chemical Industry [source] Aflatoxin contamination of consumer milk caused by contaminated rice by-products in compound cattle feedJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2009Erik Nordkvist Abstract BACKGROUND: Elevated levels of aflatoxin M1 were observed in routine checks of consumer milk in southern Sweden in early 2006. A trace-back study revealed contaminated milk from several farms, and a total of 68 farms were banned from delivering milk to dairies for shorter or longer periods. The maximum level of aflatoxin M1 in a single sample from an individual farm was 257 ng kg,1 fresh milk. RESULTS: Aflatoxin analyses of commercial compound feed revealed that the contamination originated from the ingredient rice feed meal, a by-product from the preparation of Basmati rice for human consumption. Up to 56 µg kg,1 of aflatoxin B1 was found in rice feed meal at one feed mill. CONCLUSION: The present example shows that an aflatoxin-contaminated minor feed ingredient included at less than 10% (w/w) of compound cattle feed can significantly contaminate the milk produced. This emphasises the need for effective monitoring of the feed chain of food-producing animals in order to prevent food contamination. Copyright © 2008 Society of Chemical Industry [source] Inclusion of macroalgae meal (Macrocystis pyrifera) as feed ingredient for rainbow trout (Oncorhynchus mykiss): effect on flesh fatty acid compositionAQUACULTURE RESEARCH, Issue 1 2009Patricio Dantagnan Abstract The use of macroalgae as an additional component in animal feeding has been studied. However, information on how it could influence muscle composition of fish body is scarce. This study evaluates four diets with different macroalgae inclusion levels (0%, 1.5%, 3% and 6%) to test the effect on body fatty acid composition of rainbow trout. Tanks with a volume of 600 L were stocked with 60.6 ± 7.9 g fish at a density of 45 individuals tank,1 and fed for 124 days. At the end of the experiment there were not significant differences (P<0.05) in muscle proximate composition among fish fed the different treatments. However, it was determined that inclusion of 3% and 6% of macroalgae meal resulted in a significant increase (P<0.05) of polyunsaturated fatty acids (PUFAs) in muscle. In summary, macroalgae meal in rainbow trout diets do not enhance the quantity of protein and lipid contents at muscle level but an addition of 3,6% might contribute to increase the level of PUFAs, specially EPA, DHA and LIN. Thus, use of macroalgae meal might help to increase lipid quality content in the final product due the beneficial effects of PUFAs for human health. [source] Evaluation of pea protein isolate as alternative protein source in diets for juvenile tilapia (Oreochromis niloticus)AQUACULTURE RESEARCH, Issue 5 2007Carsten Schulz Abstract To evaluate isolated pea protein as feed ingredient for tilapia (Oreochromis niloticus) juveniles, triplicate groups were fed with four isonitrogenous [crude protein: 421.1,427.5 g kg,1 in dry matter (d.m.)] and isoenergetic (gross energy: 20.46,21.06 MJ kg,1 d.m.) diets with varying protein sources for 8 weeks. Fish meal-based protein content of diets was substituted with 0% (diet 100/0=control group), 30% (diet 70/30), 45% (diet 55/45) and 60% (diet 40/60) isolated pea protein. Tilapia juveniles with an initial body weight of 2.23,2.27 g were fed in average at a level of 5% of their body weight per day. Highest individual weight gain (WG: 21.39 g) and specific growth rate (SGR: 4.21% day,1) and best feed conversion ratio (FCR: 0.90) were observed in tilapia fed diet 100/0, followed by fish-fed diet 70/30 (WG: 19.09 g; SGR: 4.03% day,1; FCR: 0.98), diet 55/45 (WG: 16.69 g; SGR: 3.80% day,1; FCR: 1.06) and diet 40/60 (WG: 16.18 g; SGR: 3.74% day,1; FCR: 1.06). Although fish fed diet 100/0 showed the best performance, inclusion of 30% protein derived from pea protein isolate resulted in a growth performance (in terms of WG and SGR) that did not differ significantly from diet 100/0 in contrast to fish fed diet 55/45 and 40/60. Crude ash content in the final body composition of the experimental fish decreased with increasing dietary pea protein content, while crude protein and lipid content remained equal between the groups. Significant decreasing growth performance and body ash incorporation of tilapia at higher inclusion levels seem to be mainly related to the dietary amino acid profile and phytic acid contents. [source] Potential of local agricultural by-products for the rearing of African catfish Clarias gariepinus in Rwanda: effects on growth, feed utilization and body compositionAQUACULTURE RESEARCH, Issue 2 2007Laetitia Nyina-wamwiza Abstract This study was performed to evaluate the effect of replacing fish meal with local by-products on Clarias gariepinus growth performance, feed utilization and body composition. A control diet contained 50% of fish meal. In four other diets, fish meal was partially replaced by vegetable and animal protein blend composed of sunflower oil cake, soybean oil cake, groundnut oil cake, bean meal, chicken viscera and blood meal. The study was conducted in a recirculating water system at a mean temperature of 23.6°C. The five test diets were compared with a commercial diet developed for African catfish. All diets were balanced to be equal in gross energy (19 kJ g,1) and crude protein (40%). The experimental groups were fed in triplicate for 8 weeks, increasing fish weight from about 6.2 g at start to 52.3 g in the end. Best specific growth rate (SGR=3.4), feed efficiency (FE=1.3) and protein efficiency ratio (PER=3) were obtained with the control diet (diet 50% fish meal), although there were no significant differences between the group of fish fed the control diet and those fed diets based on groundnut oil cake or bean meal, whereas SGR (2.17), FE (0.85) and PER (1.95) were significantly (P<0.01) lower in fish fed diet containing sunflower oil cake. No significant differences (P<0.05) were found in fish fed commercial diet and diets containing bean meal or groundnut oil cake. Groundnut oil cake or bean meal can thus replace at least 50% of fish meal in the diet of Clarias fingerlings without amino acid supplementation. Because of its economic importance and its potential in animal nutrition sunflower oil cake is still an interesting feed ingredient, but its efficiency should be improved by various processing techniques. African catfish can utilize efficiently a diet with low percentage of animal protein without growth reduction. [source] Chapter 6: Maize with Increased Lysine (Lysine Maize,LY038)COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2008Article first published online: 30 JAN 200 ABSTRACT:, Data and information provided in this case study relate to a crop derived by modern biotechnology, in which a specific nutrient (lysine) has been increased in maize grain.Lysine maize is a feed ingredient with enhanced nutritional characteristics for poultry and swine and provides an alternative to adding supplemental lysine to diets for these animals. Lysine maize is in an advanced state of development; therefore, extensive unpublished data and information are presented to demonstrate that (1) Lysine maize,and the feeds and foods derived from it,are as safe as those derived from conventional maize,and (2) the increased lysine in Lysine maize grain produces the intended nutritional benefit for broiler chickens when compared to a diet containing conventional maize grain and a crystalline lysine supplement. These conclusions are based on a detailed molecular characterization of Lysine maize,a safety assessment of the introduced protein,a safety and nutritional assessment of the LY038 crop,and a comparison of the agronomic and phenotypic properties of maize hybrids with and without the Lysine maize trait. Although Lysine maize is a specialty crop for use in animal feed,its safety for both animals and humans must be demonstrated. Free lysine is significantly increased in Lysine maize by the introduction of the dapA gene (cordapA) from Corynebacterium glutamicum that encodes a form of dihydrodipicolinate synthase (cDHDPS) that is insensitive to lysine feedback inhibition.Analysis of lysine anabolic and catabolic pathways in maize identified 6 metabolites that might change as a consequence of the introduction of cDHDPS insensitive to lysine-feedback inhibition. The results of compositional analysis demonstrated that Lysine maize grain is comparable to conventional maize, with the exception of the intended increase in lysine and a corresponding increase in 2 products of lysine catabolism,saccha-ropine and -aminoadipic acid. Therefore, the safety and/or nutritional implication of these 3 compounds under the conditions of use were the focus of additional assessments and found to not present either a safety or nutritional problem. [source] Bioconversions of maize residues to value-added coproducts using yeast-like fungi,FEMS YEAST RESEARCH, Issue 2 2003Timothy D Leathers Abstract Agricultural residues are abundant potential feedstocks for bioconversions to industrial fuels and chemicals. Every bushel of maize (approximately 25 kg) processed for sweeteners, oil, or ethanol generates nearly 7 kg of protein- and fiber-rich residues. Currently these materials are sold for very low returns as animal feed ingredients. Yeast-like fungi are promising biocatalysts for conversions of agricultural residues. Although corn fiber (pericarp) arabinoxylan is resistant to digestion by commercially available enzymes, a crude mixture of enzymes from the yeast-like fungus Aureobasidium partially saccharifies corn fiber without chemical pretreatment. Sugars derived from corn fiber can be converted to ethanol or other valuable products using a variety of naturally occurring or recombinant yeasts. Examples are presented of Pichia guilliermondii strains for the conversion of corn fiber hydrolysates to the alternative sweetener xylitol. Corn-based fuel ethanol production also generates enormous volumes of low-value stillage residues. These nutritionally rich materials are prospective substrates for numerous yeast fermentations. Strains of Aureobasidium and the red yeast Phaffia rhodozyma utilize stillage residues for production of the polysaccharide pullulan and the carotenoid astaxanthin, respectively. [source] Taurine concentrations in animal feed ingredients; cooking influences taurine contentJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 7-8 2003A. R. Spitze Summary The aim of this study was to determine the taurine content in a variety of animal feeds. There is very little information on the taurine content of ingredients used in home-prepared diets for dogs and cats, and foods fed to wild animals in captivity. This study reports the taurine content of both common and alternative feed ingredients, and compares taurine loss as a result of different methods of food preparation. Foods were selected based on their use in commercial and home-prepared diets. Animal muscle tissue, particularly marine, contained high taurine concentrations. Plant products contained either low or undetectable amounts of taurine. The amount of taurine that remained in a feed ingredient after cooking depended upon the method of food preparation. When an ingredient was constantly surrounded by water during the cooking process, such as in boiling or basting, more taurine was lost. Food preparation methods that minimized water loss, such as baking or frying, had higher rates of taurine retention. [source] Effects of vegetable feed ingredients on bone health in Atlantic salmonJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010P. G. Fjelldal Summary The aim of the present study was to examine if dietary inclusion of vegetable lipids (VL) and proteins (VP) influenced markers of bone health in Atlantic salmon. Triplicate groups were fed one of four different diets; 100% fish protein (FP) and fish lipids (FL) (FPFL), 80% VP and 35% VL (80VP35VL), 40% VP and 70% VL (40VP70VL), or 80% VP and 70% VL (80VP70VL) for 12 months on-growth in sea water. Fish were analyzed for vertebral bone mineralization (mineral content, as % of bone dry weight), vertebral deformities (radiology), vertebral bone mRNA expression of factors involved in mineralization (bone gla protein, bgp) and growth regulation (igf-I and growth hormone receptor), as well as plasma vitamin D metabolites. The fish grew from 0.35 to 4 kg during the experimental period. At the end of the experiment, significantly lower prevalence of fish with one or more deformed vertebrae was observed in the 80VP70VL group (11%) compared to the other groups (33,43%). There was a significant higher relative expression of igf -I mRNA in vertebral bone of fish fed the 80VP70VL diet compared to control fish (FPFL), while the other genes studied were unaffected. Elevated plasma 25-hydroxyvitamin D3 recorded in the marine feed group is discussed as a predictor for later development of bone deformities. In conclusion, the present study shows that high inclusion levels of vegetable lipids and proteins may have a positive effect on bone health in Atlantic salmon postsmolts. [source] PROPERTIES OF DIFFERENT FISH PROCESSING BY-PRODUCTS FROM POLLOCK, COD AND SALMONJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2003PETER J. BECHTEL Individual fish processing waste stream components can be used to make feed ingredients or other products. Waste stream components obtained from commercial fish processing plants included heads, viscera, frames, and skins from Alaska pollock (Theragra chalcogramma) and Pacific cod (Gadus macrocephalus); and heads, and viscera from pink salmon (Oncorhynchus gorbuscha). The protein content of heads from all three species ranged from 13.9 to 16.4%; and the fat content ranged from 0.9 to 10.9%. Viscera protein content ranged from 13.0 to 15.3%, and the fat content from 2.0 to 19.1%. After heating to 85C the percent soluble protein in salmon heads was different (P < 0.05) from pollock or cod heads. Percent soluble protein of pollock and cod skin increased 8fold (P<0.05) after the 85C heat treatment. Connective tissue content was calculated from chemical determination of hydroxyproline content, and large differences in percent connective tissue content were found (1% for pollock viscera to 46% for skin). Estimated rat PER values ranged from a low of 2.1 for skin to a high of 3.1 for viscera and fillet samples (P<0.05). [source] Effects of Fungal Phytase on Utilization of Dietary Protein and Minerals, and Dephosphorylation of Phytic Acid in the Alimentary Tract of Channel Catfish Ictalurus punctatus Fed an All-Plant-Protein DietJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2002Weibing Yan A feeding trial was conducted to quantify the effects of phytase at levels of 0, 500, 1,000, 2,000, 4,000, and 8,000 units (U) per kg diet on utilization of dietary protein and minerals by fingerling (12 g) channel catfish Ictalurus punctatus fed an all-plant-protein diet composed of soybean meal, corn, and wheat middlings. The effects of phytase on dephosphorylation of phytic acid (phytate) in the alimentary tract of catfish also were determined. After 14 wk, mean weight gains (30.2,43.9 g/fish), feed conversion ratios (2.27,2.40 g feed consumed/g weight gain), protein efficiency ratios (1.47,1.61 g weight gaid/g protein consumed), and dietary protein retentions (23.8,26.7%) did not differ significantly (P > 0.05) among treatment groups. A digestibility trial conducted after the feeding trial showed no difference (P > 0.05) in mean digestibility of diet dry matter (49.0,58.3%) or crude protein (85.4-88.5%) among treatment groups. Concentrations of ash (46.7,48.6%), calcium (Ca, 17.9,18.5%), phosphorus (P, 9.1,9.5%), and manganese (Mn, 65.5,74.1 mg/kg) were significantly higher (P , 0.05) in bone of fish fed , 500 U/kg than in bone of fish fed 0 U/kg (ash, 43.5%; Ca, 16.4%; P, 8.4%; and Mn, 49.0 ma/kg), but concentrations of these minerals did not differ (P > 0.05) in bone of fish fed , 500 Uk/g. The magnesium (Mg) content of bone did not differ (P > 0.05) between fish fed 0 U/kg (0.29%) or 500 U/kg (0.34%), but was significantly lower in fish fed 0 U/kg than in fish fed , 1,000 U/kg (0.35,37%). Bone Mg levels did not differ (P > 0.05) among fish fed , 500 U/kg. The amount of zinc (Zn) in bone of fish fed 8,000 U/kg (153.3 mg/kg) was significantly higher than that in fish fed 0 U/kg (115.7 mg/kg) or 500 U/kg (130.3 mg/ kg), but did not differ from Zn levels in bone of fish fed 1,000,4,000 U/kg (134.5,135.8 mg/ kg). Dephosphorylation of phytate occurred primarily in the stomach within 2,8 h after diet ingestion, depending on the level of phytase supplementation. Initial levels of total phytate in the diet decreased 32,94% in stomach contents of fish fed l,000,8,000 U/kg within 2 h after feeding. Eight hours after feeding, stomach contents of fish fed , 1,000 U/kg contained less than 6% of initial total dietary phytate. Stomach contents of fish fed 500 U/kg retained 92% of initial total dietary phytate 2 h after feeding and 15% of total dietary phytate 8 h after feeding. Results of this study indicate that phytase supplementation at levels up to 8,000 U/kg diet did not increase weight gain or improve dietary protein utilization of channel catfish fed an all-plant-protein diet. Addition of phytase at a level of 1,000 U/kg diet was sufficient to significantly increase the Ca, P, Mg, and Mn content of bone, relative to fish fed an unsupplemented diet, and significantly decrease the quantity of total phytate in feces. A phytase level of 8,000 U/kg diet significantly increased the bioavailability of naturally occurring Zn in feed ingredients and increased the rate of phytate dephosphorylation in the stomach, compared with a diet containing no added phytase. Increased utilization of naturally occurring minerals in feed ingredients reduces the need for mineral supplements in diets and results in decreased elimination of minerals in feces. Thus, use of phytase in catfish feeds can be expected to provide both economic and environmental benefits. [source] Assessment of methods for the determination of digestibilities of feed ingredients for Tra catfish, Pangasinodon hypothalamusAQUACULTURE NUTRITION, Issue 4 2010T.T.T. HIEN Abstract In this study, we undertook a series of experiments to assess different faecal-collection methods and also the digestibilities of a range of feed ingredients when fed to Tra catfish (Pangasinodon hypothalamus). Apparent digestibility coefficients for dry matter, energy and nitrogen for a reference diet were also determined from faeces collected by way of settlement at 2-h intervals from 2 to 24 h. No significant effect of sample collection time on the digestibility values was observed. Stripping was attempted, but was not considered a suitable method for collecting digesta from Tra catfish. Dissection collection was also evaluated. Values determined from dissection collection were lower than those from using settlement. In a second experiment, a suite of test ingredients was combined with a reference diet component in a 30 : 70 ratio to determine the ingredients for dry matter, energy and nitrogen digestibilities. Ingredients included were trash-fish, defatted rice bran, wet full-fat rice bran, dried full-fat rice bran, broken rice, cassava, soybean and fish meals. Collection of faeces by settlement was used for determining the digestibility of each of the ingredients. The results showed that Tra catfish can efficiently digest protein and energy from a wide range of feed ingredients and nutrient sources. [source] Apparent amino acid availability from feedstuffs in extruded diets for rainbow trout Oncorhynchus mykissAQUACULTURE NUTRITION, Issue 4 2010T.G. GAYLORD Abstract Apparent amino acid availability coefficients of several typical and novel feed ingredients were determined in rainbow trout using extruded diets and the faecal stripping technique. The ingredients were tested included five fish meals, three terrestrial animal by-products, five plant protein concentrates, four plant meals, and seven low-protein plant ingredients. Amino acid availability from the fish meals was relatively high ranging from 90 to 101%. Lower coefficients overall were observed for Menhaden fish meal FAQ when compared to the other fish meals. No differences in apparent amino acid availability were detected among the animal by-products. Within the plant concentrate group, rice protein concentrate and barley protein concentrate exhibited generally lower amino acid availabilities compared to other concentrates tested. Among the plant meals, only the availabilities of histidine, valine, isoleucine and lysine in flaxseed meal were lower than those of soybean meal. Apparent amino acid availabilities among the low-protein plant products were variable and significantly different. [source] A comparison of two faecal collection methods for protein and amino acid digestibility coefficients of menhaden fish meal and two grades of poultry by-product meals for market-size sunshine bass (Morone chrysops × M. saxatilis)AQUACULTURE NUTRITION, Issue 1 2010S.D. RAWLES Abstract Apparent digestibility and availability coefficients for protein and amino acids in menhaden fish meal (MEN), pet-food grade (PBM-pet,) and feed-grade poultry by-product meal (PBM-feed) were determined for market-size (500 g) sunshine bass in two consecutive trials using passive netting (1.6 mm mesh) followed by manual stripping of faeces. A reference diet resembling a commercial feed was formulated to meet or exceed all known nutritional requirements of hybrid striped bass. Test diets were formulated to contain a 70 : 30 mixture of reference diet to test ingredient with chromic oxide (1%) serving as the inert marker. Diets were extruded under commercial conditions and the reference diet was fed for two weeks in order to acclimate fish to experimental conditions. Each diet was randomly assigned to triplicate tanks containing 30 fish each. Fish were fed their respective diet twice daily to apparent satiation for two weeks, with faecal collections being conducted on the 7th and 14th day, in each trial. ADC values determined in the net method were highly variable and generally lower than ADCs obtained by stripping. Consistently lower and highly variable chromium concentrations were found in the net method faecal samples and suggest that marker loss relative to nutrient content, or dilution of marker with non-faecal matter, on the net collectors influenced results in that trial. In contrast, the standard errors of ADCs determined in the strip method were less than 5 percentage points in most cases. Protein digestibility ranged from a low of 51% (PBM-feed) to a high of 87% (PBM-pet) in the net method, and from a low of 80% (PBM-feed) to a high of 99% (MEN) in the strip method. With the exception of Lys, no differences in amino acid availabilities among diets were found in the net method. In the strip method, protein digestibility and amino acid availabilities in MEN were generally greater than those found in PBM-pet or PBM-feed, whereas ADCs were not significantly different between the two poultry by-products. Based on the conditions of the present study, net collection of faecal matter can not be recommended for determining the digestibility of nutrients in feed ingredients for market-size sunshine bass. Digestibility coefficients obtained by the strip method for feed and petfood grades poultry by-product were higher than those previously reported and will be facilitate more efficient and economical diet formulations for larger sunshine bass. [source] A method to determine protein digestibility of microdiets for larval and early juvenile fishAQUACULTURE NUTRITION, Issue 6 2009J.M. HANSEN Abstract A method to evaluate protein quality using in vivo methods was developed for larval fish. FluoSpheres® fluorescent microspheres (10 ,m) were incorporated into two test diets, our standard zein microdiet (ZMD) and a microdiet with identical ingredients except for the replacement of high quality fish meal with the same product cooked for 24 h at 80 °C (ZMD-CF). Several trials were performed to design a reliable method to test digestibility using FluoSpheres® as a marker. The developed in vivo technique was tested on 35 days posthatch (dph) larval Atlantic cod (Gadus morhua L.) and two tropical fish species in the early juvenile stage. The method took into account loss of total protein to the faecal pellet and water column. Apparent digestibility of protein in larval cod fed ZMD was significantly higher than that of larvae fed ZMD-CF (P < 0.05). A growth study to validate differences between the two diets showed significant differences in growth and survival of larvae fed ZMD versus ZMD-CF (P < 0.05). Further validation of our results was indicated through the use of a pH-stat method using enzymes extracted from 35 dph larval cod guts. This novel technique will be advantageous for researchers to evaluate feed ingredients for larval marine fish and is adaptable to many different areas of larval fish nutrition. [source] Dietary menadione nicotinamide bisulphite (vitamin K3) does not affect growth or bone health in first-feeding fry of Atlantic salmon (Salmo salar L.)AQUACULTURE NUTRITION, Issue 6 2009C. KROSSŲY Abstract The aim of the present study was to elucidate if increasing levels of added vitamin K in the feed influenced fish growth, health or the incidences of bone deformities in Atlantic salmon (Salmo salar L.) from onset of start feeding to ,100 g in freshwater. Duplicate groups of Atlantic salmon fry (,0.20 g) were fed eight levels (0, 2.5, 5, 7.5, 10, 15, 20 and 50 mg menadione kg,1) of the vitamin K derivate menadione nicotinamide bisulphite (MNB) in a regression design for 28 weeks. All fish maintained high growth rates throughout the experiment, and showed no significant differences in specific growth rate, condition factor, whole body proximate analysis, blood coagulation time, vertebra morphology or mechanical properties of vertebrae. We found a dose-response between whole body vitamin K concentration and the dietary MNB supplementation level. Analysis of liver ,-glutamylcarboxylase activity revealed significant dose-dependent differences between groups given the 0, 10 and 50 mg MNB kg,1 diets. In conclusion, Atlantic salmon seems to require low levels of dietary vitamin K, and the amount of vitamin K found naturally in the presently used feed ingredients may be enough to maintain optimal growth, health and bone strength in Atlantic salmon fry from start feeding. [source] Apparent digestibility coefficients of selected feed ingredients for dourado Salminus brasiliensisAQUACULTURE NUTRITION, Issue 5 2009R. BORGHESI Abstract The excellence of its flesh and fast growth makes the dourado, Salminus brasiliensis, a carnivorous fish native to the Prata basin, a potential candidate for intensive fish farming. This study evaluated the apparent digestibility coefficients (ADC) of energy and nutrients of animal and plant protein sources for the carnivorous Characin dourado S. brasiliensis. Fish (19.5 ± 5.0 g) were stocked in plastic cages (80-L) and fed pelleted test diets containing 30% of the test ingredient [fish meal (FM), poultry by-product meal (PBM), soybean meal (SBM), and corn gluten meal (CGM) plus 70% of a reference diet (481.4 g kg,1 of crude protein and 18.63 kJ of gross energy per gram]. After the last daily meal, cages were transferred to cylindrical, conical-bottomed aquarium (200-L) where faeces were collected by sedimentation in a refrigerated container. Except for ADC of protein and energy, all other ADC of nutrients showed significant differences (P < 0.01). ADC values were: 94.3%, 91.3%, 93.1%, and 93.5% for crude protein; 91.0%, 90.3%, 87.8%, and 88.8% for gross energy; 92.1%, 84.5%, 80.6%, and 79.3% for ash; 83.9%, 80.3%, 84.3%, and 84.6% for dry matter; 97.4%, 96.7%, 93.3%, and 91.5% for lipid for FM, PBM, SBM, and CGM, respectively. The average amino acid ADC was: 93.6%, 90.0%, 92.1%, and 92.5% of FM, PBM, SBM, and CGM, respectively. All test ingredients were efficiently used and can partially replace FM in diets for carnivorous dourado. [source] Protein quality of larval feed with increased concentration of hydrolysed protein: effects of heat treatment and leachingAQUACULTURE NUTRITION, Issue 5 2009A. NORDGREEN Abstract Four heat coagulated early weaning diets with increasing concentrations of pepsin hydrolysed protein, were investigated with regard to the change in protein quality during feed production and exposure to leaching. Water-soluble N, trichloroacetic acid-soluble N and amino acid (AA) profiles were determined in finished diets and in diets leached for 6 min. In vitro diet digestibility was measured and related to increasing inclusion of hydrolysed protein and N leakage. Seventeen to 47% of soluble N in the feed ingredients was made insoluble by heat denaturation during feed production, but the concentration of peptides and free amino acids (FAA) were not influenced. All peptides/FAA and 70,80% of water-soluble protein were lost after exposure to leaching. Increased inclusion of hydrolysed protein increased the loss of crude protein (15,30%). All taurine and 30% of histidine was lost during leaching, no other major changes in AA profile were found. There was no difference in digestibility between diets exposed to leaching. However, leached diets showed reduced digestibility as compared to diets that had not been exposed to leaching. In conclusion micro-bound type diets as used in this study have a low efficiency in delivering soluble N to fish larvae and should be carefully considered for this purpose. [source] Linear models to predict the digestible lipid content of fish dietsAQUACULTURE NUTRITION, Issue 5 2009J. SALES Abstract Values for the digestible contents of nutrients in diets and feed ingredients are of utmost importance in nutritional strategies for fish. Prediction from dietary composition would eliminate lengthy, tedious and demanding digestibility experiments with fish. Apparent digestible lipid (DL) content [range 7.6,353.4 g kg,1 dry matter (DM)] in compound diets can be predicted with high accuracy (n = 610; studies =127; fish species = 34; R2 = 0.9515; RMSE = 16.9504) from dietary crude lipid (CL) content (range 12.0,388.7 g kg,1 DM) by the linear regression equation DL =,2.7303 + 0.9123 CL. Validation of this equation against 65 values from 15 independent studies presented R2 and mean prediction error (MPE) values of 0.9947 and 0.0671, respectively. The corresponding equation for 37 individual feed ingredients evaluated in 24 studies with 18 fish species (n = 180) was found to be DL = ,1.5824 + 0.8654 CL (R2 = 0.9717; RMSE = 8.3765). However, validation of the latter is currently hampered by a lack of independent values. [source] Apparent digestibility of nutrients and energy in extruded diets from cultivars of barley and wheat selected for nutritional quality in rainbow trout Oncorhynchus mykissAQUACULTURE NUTRITION, Issue 3 2009T.G. GAYLORD Abstract A digestibility trial was conducted to elucidate potential differences in barley (Hordeum vulgare L.) lines and varieties as a first step in defining their potential for use in aquafeeds. A diverse group of six barley lines having six combinations of selected attributes, normal versus low phytic acid, normal versus waxy, and hulled versus hull-less, were chosen for evaluation along with a waxy wheat (Triticum aestivum L.) and soft white wheat. The experimental diets were manufactured by cooking extrusion and consisted of a 70% reference diet that was formulated to contain a minimal level of phosphorus and 30% test ingredient. Phosphorus availability ranged from 17 to 78% and was influenced by starch type in wheat. Apparent protein digestibility ranged from 53 to 125% and differences were observed between wheat varieties based on starch type. Apparent energy digestibility ranged from 32 to 63%, with waxy barley varieties having higher energy digestibility coefficients than normal starch varieties. Waxy starch varieties had higher starch digestibility in both barley and wheat because of the greater digestibility of amylopectin than amylose. In summary, the higher energy digestibility of waxy barley lines suggests that these varieties warrant further attention as feed ingredients for rainbow trout. [source] Evaluation of cottonseed meal derived from genetically modified cotton as feed ingredients for channel catfish, Ictalurus punctatusAQUACULTURE NUTRITION, Issue 6 2008M.H. LI Abstract Three laboratory experiments were conducted to assess nutritional quality of cottonseed meals from genetically modified (GM) cotton crops, Roundup Ready® Flex, Bollgard® × Roundup Ready, Bollgard II® × Roundup Ready, and Bollgard II × Roundup Ready Flex for channel catfish, Ictalurus punctatus using Good Laboratory Practices. Growth, feed efficiency, survival, and fillet composition of catfish fed diets containing 20% cottonseed meal from these cotton products were compared with that of catfish fed diets containing cottonseed meals from the near-isogenic, non-GM control and non-GM commercial varieties. Juvenile catfish (mean weights of 4.1, 5.0, and 0.6 g per fish for Experiments 1, 2, and 3, respectively) were stocked in each of 80-L aquaria and fed experimental diets for 8 weeks. Although there were slight variations in proximate composition, amino acids, and gossypol concentrations, the GM cottonseed meals were not significantly different from the conventional control and the reference cottonseed meals. Weight gain, feed conversion, survival, and fillet composition of catfish fed GM cottonseed meals appeared similar to that of either the control or the commercial cottonseed meals. Results from the present study demonstrate that these GM cottonseed meals are nutritionally equivalent to conventional non-GM cotton varieties when fed to catfish at 20% of the diet. [source] Amino acid availability and protein digestibility of several protein sources for Nile tilapia, Oreochromis niloticusAQUACULTURE NUTRITION, Issue 5 2008I.G. GUIMARĆES Abstract Apparent amino acid availability coefficients and protein digestibility of four animal products [fish meal (FM), meat and bone meal (MBM), poultry by-product and feather meal] and four plant protein-rich products [soybean meal (SBM), cottonseed meal-28, cottonseed meal-38 and corn gluten meal (CGM)] were determined for Nile tilapia, Oreochromis niloticus. Ingredients were incorporated to a practical reference diet at a 7 : 3 ratio (70% of reference diet and 30% of test ingredient). Chromic oxide was used as external digestibility marker. Among animal products poultry by-product meal (PBM; 89.7%) and FM (88.6%) presented the highest apparent protein digestibility (APD) while MBM (78.4%) and feather meal (78.5%) presented the lowest APD. Among plant protein-rich products CGM (91.4%) and SBM (92.4%) presented the highest APD values while cottonseed meal-28 presented the lowest APD (78.6%). Average apparent amino acid availability of feed ingredients was similar to protein digestibility with 92.3%, 89.6%, 73.4%, 80.7%, 88.9%, 84.4%, 91.2% and 79.7% values for SBM, CGM, cottonseed meal-28 and 38, FM, MBM, PBM and feather meal respectively. These results indicate that O. niloticus is able to utilize efficiently different feedstuffs. [source] A feed is only as good as its ingredients , a review of ingredient evaluation strategies for aquaculture feedsAQUACULTURE NUTRITION, Issue 1 2007B.D. GLENCROSS Abstract The evaluation of feed ingredients is crucial to nutritional research and feed development for aquaculture species. In evaluating ingredients for use in aquaculture feeds, there are several important knowledge components that should be understood to enable the judicious use of a particular ingredient in feed formulation. This includes information on (1) ingredient digestibilities, (2) ingredient palatability and (3) nutrient utilization and interference. Diet design, feeding strategy, faecal collection method and method of calculation all have important implications on the determination of the digestible value of nutrients from any ingredient. There are several ways in which palatability of ingredients can be assessed, usually based on variable inclusion levels of the ingredient in question in a reference diet and feeding of those diets under an apparent satietal or self-regulating feeding regimes. However, the design of the diets, the parameters of assessment and the feeding regime can all be subject to variation depending on subtleties of the experimental design. Clearly, issues relating to feed intake are the key performance criteria in palatability assessments, and it is important that such experiments maintain sufficient stringency to allow some self-discrimination of the test feeds by the fish. The ability of fish to use nutrients from the test ingredient, or defining factors that interfere with that process, is perhaps the most complex and variable part of the ingredient evaluation process. It is crucial to discriminate effects on feed intake from effects on utilization of nutrients from ingredients (for growth and other metabolic processes). To allow an increased focus on nutrient utilization by the animals, there are several experimental strategies that can be adopted, which are based on variations in diet design and feeding regime used. Other issues such as ingredient functionality, influence on immune status and effects on organoleptic qualities are also important consideration in determining the value of ingredients in aquaculture feed formulations. A key aspect to note is the need to design all experiments with sufficient experimental capacity to detect significant effects. [source] Effects of extrusion processing of feed ingredients on apparent digestibility coefficients of nutrients for rainbow trout (Oncorhynchus mykiss)AQUACULTURE NUTRITION, Issue 2 2003Zongjia J. Cheng Abstract An experiment was conducted to evaluate the effects of extrusion processing on apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude fat, energy and minerals in soya bean meal (SBM), barley, corn gluten meal and whole wheat, using rainbow trout Oncorhynchus mykiss as the test species. In addition, availabilities of amino acids were also determined in SBM. Feed ingredients were preconditioned at 89,93 °C and then extruded using a Wenger X-85 extruder. Nonextruded ingredients were used as is, meaning that they were not preconditioned. The extruded and nonextruded ingredients were mixed with a casein,gelatin reference diet at 3 : 7 ratio prior to determination of ADC values. A total of 135 trout (initial mean body weight 223.4 ± 12.7 g) were stocked into nine 140-L fibreglass digestibility tanks with 15 fish per tank. Individual tanks were assigned randomly to each of eight diets made from the four ingredients (extruded and nonextruded) plus the reference diet. After faeces were collected in the first week, the diets were switched among tanks, and faeces were collected again after 5-day acclimation period in the second week. Yttrium oxide was used as the inert marker. Results showed that extrusion processing significantly improved ADCs of dry matter, crude fat and gross energy, and reduced ADCs of crude protein, phosphorus, copper, iron and zinc. Results also showed that the effects of extrusion processing on chemical composition and ADCs of nutrients depended on the ingredients. It is recommended that trace minerals such as copper, iron and zinc be supplemented by an additional 10,20% when rainbow trout diets are extruded because of their reduced bioavailability in plant meal-based feed ingredients. [source] Apparent digestibility of selected feed ingredients in diets for juvenile hybrid tilapia, Oreochromis niloticus×Oreochromis aureusAQUACULTURE RESEARCH, Issue 9 2010Xiao-Hui Dong Abstract The apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, ash, phosphorus, gross energy and amino acids of 10 selected ingredients for juvenile hybrid tilapia (7.05 ± 0.09 g) were determined using 0.5% Cr2O3 as an inert indicator. The feed ingredients tested in this study were corn gluten meal (CGM), corn byproduct, corn germ meal (CG), soybean meal (SBM), fermented soybean meal (FSM), soy protein concentrate (SPC), soy protein isolate, malt sprouts (MS), fish meal (FM) and earthworm meal (EM). The test diets were prepared by incorporation of 30% test ingredients into the reference diet. Reference and test diets were fed to the fish and the faecal samples were collected using a faecal collection column attached to the fish-rearing tanks. The ADCs for dry matter, crude protein, crude lipid, ash, phosphorus and gross energy were 41.7,98.9%, 90.6,99.6%, 73.1,98.8%, 34.1,98.6%, 49.5,99.6% and 45.4,99.7% respectively. Soy protein isolate, FM and EM had higher dry matter, crude protein and gross energy ADCs. Corn byproduct and EM had higher crude lipid ADCs, and CG and EM had higher phosphorus ADCs. Corn germ meal had the highest ash ADC, while CGM had the highest value for gross energy. The lowest dry matter, crude protein, lipid and gross energy ADCs occurred in MS, while the lowest ash and phosphorus ADCs occurred in SPC. The amino acid ADCs ranged from 83.3% to 100%, exhibiting a positive correlation with crude protein digestibility for a given test ingredient. The feed ingredient digestibility of this study may provide useful information about nutrient and energy utilization to facilitate formulation of least-cost practical diets for hybrid tilapia. [source] | ||||||||||||||||