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1.
Decreasing diet cost and minimizing environmental impact are current issues that can affect the success of poultry production. In the eastern United States, much concern has been generated surrounding eutrophication of the Chesapeake Bay due to nitrogen and phosphorus leaching from land application of litter. Gasification of poultry litter and feeding the resultant poultry litter biochar (PLB) may be an alternative to traditional land application of litter. In addition, PLB may provide a cost-effective source of essential nutrients for poultry by the partial or complete replacement of rock phosphorus in poultry diets, and may also provide a mechanism for improving feed manufacture variables. The objectives of this study were to assess effects of diet incorporation of PLB on feed manufacture and pellet quality (Study 1) and subsequent feeding effects on broiler performance and tibia ash (Study 2). Seven diets were formulated to compare the replacement of rock phosphorus with PLB. Inclusion of PLB was high, 6.2 or 6.9%, in order to maximize rock phosphorus replacement but also to assess potential detriments. Four diets were chosen to generate replicated feed manufacture and pellet quality data. The addition of PLB to diets was shown to improve pellet quality (P < 0.05). Diets containing PLB decreased live weight gain and FCR; however, a positive yet modest contribution to bone mineralization was demonstrated (P < 0.0001). Therefore, PLB contains available phosphorus and calcium; however, the bioavailability of these minerals relative to rock phosphorus was not equivalent. Furthermore, the particular PLB tested decreased broiler performance.  相似文献   

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Recent technological advances in the human food industry with respect to meat processing have decreased the availability of animal proteins to the pet food industry which typically formulates diets with an excess of animal protein. In the long term, this is not sustainable; thus, alternative protein sources need to be investigated. This study examined three canine diets, comparing a typical animal protein‐based diet (control) with two experimental diets where the animal protein was substituted in part with vegetable protein (formulated based either on total protein or amino acid content) using a broiler model. Each diet was fed to six cages each containing two birds from day 15, 18 cages in total (36 birds). Excreta were collected from days 19 to 21. On day 23, birds were euthanized and weighed, and their ileal digesta were collected and pooled for each cage. In addition, one leg per cage was collected for evaluation of muscle mass. Results showed no significant difference in animal performance (feed intake or live weight gain) or muscle to leg proportion across the diets. Birds fed the control diet and the diet balanced for amino acid content exhibited the greatest coefficients of apparent metabolizability for nitrogen (p < .001). Birds fed the diets that contained partial replacement of animal with vegetable protein generally had greater ileal digestibility of amino acids compared to birds fed the control (animal protein) diet. Analysis of excreta showed no dietary difference in terms of dry matter content; however, birds fed the diet balanced for total protein and the diet balanced for amino acid content had significantly greater excreta nitrogen than the control (= .038). Overall, the study suggests vegetable proteins when formulated based on amino acid content are a viable alternative to animal proteins in canine diets.  相似文献   

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Feeding broilers barley-based diets requires special consideration primarily due to effects on increased digesta viscosity and decreased nutrient digestion. Pelleting and glucanase supplementation are commonly performed prior to feeding broilers barley-based diets; however, the interaction of these practices is complex. The objective of this study was to establish a comprehensive evaluation of glucanase efficacy including: degree of processing, activity postpelleting, broiler performance, and digesta viscosity. Treatments were arranged in a 5 (diet formulation) × 2 (processing) factorial in a randomized complete block design with 8 replications/treatment. The 5 diet formulations consisted of positive control (PC), negative control (NC), glucanase A (GA) 125 or 1,000 β-Glu-U/kg feed, and glucanase B (GB) 1,000 β-Glu-U/kg feed. The PC and NC diets differed in metabolizable energy by 150 kcal/kg and enzymes were added to NC formulations. Diets were either fed as unprocessed mash or ground pellets. Diet formulation × processing did not interact for feed intake (FI), FCR, or total tract viscosity (P > 0.05); however, a trend was observed for ending bird weight, demonstrating that for ground pellets, GA 1,000 β-Glu-U/kg feed was improved relative to NC and similar to PC (P = 0.0903). Benefits associated with GB were not of similar magnitude, perhaps in part due to a 50% decrease in activity postpelleting. In addition, GA benefits were not suggested for unprocessed mash. The main effect processing was significant (P < 0.0001) demonstrating that broilers fed ground pellets resulted in greater pen ending bird weight, FI, and bird live weight gain (LWG) compared to birds fed unprocessed mash diets. Evaluations of glucanase should go beyond in vitro activity and include live bird performance using feed that has undergone pelleting.  相似文献   

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Three experiments (EXP) were conducted with the objective of evaluating the effects of varying steam conditioning temperatures (CT) and mixer-added fat (MAF) on a practical broiler finisher diet on feed manufacture variables (EXP 1), 28- to 42-d broiler performance (EXP 2), and early skeletal effect using 3-to 21-d broiler performance and tibiae ash measurements and true amino acid digestibility using cecectomized roosters (EXP 3). For all EXP, we used a 3 CT (74, 85, or 96°C) by 2 MAF (low or high) factorial arrangement, resulting in 6 experimental diets. Prior to EXP 2 and 3, all diets were ground to a common crumble size. In EXP 1, increasing both CT and MAF decreased relative electrical energy use at the pellet mill. In EXP 2, feeding finisher diets manufactured utilizing increased CT and decreased MAF to broilers from 28 to 42 d resulted in increased FCR. Also, CT by MAF interactions demonstrated the highest BW gain when birds were fed diets with high MAF, conditioned at 85°C. In EXP 3, feeding diets manufactured in EXP 1 to broilers from 3 to 21 d resulted in no significant effects on live performance variables. However, a significant CT by MAF interaction was observed, where chicks fed diets using low MAF conditioned at 85 and 96°C resulted in incrementally increased percent tibia ash over those with high MAF. In addition, based on true amino acid digestibility data, altering MAF and especially CT can affect the digestibility of several amino acids.  相似文献   

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Two experiments were conducted to assess the feeding value of water‐soaked barley (WB) as a replacement for dehulled barley (DB) in pigs. In experiment (Exp.) 1, eight barrows (body weight = 30.56 ± 0.78 kg) were fitted with a T‐cannula and allotted to a duplicated 4 × 4 Latin square design: WB10, 100g/kg WB; WB20, 200 g/kg WB; DB10, 100 g/kg DB; and DB20, 200 g/kg DB. In Exp. 2, 80 barrows (body weight = 70.56 ± 1.29 kg) were used in a 56‐day experiment: (i) WB15, 150 g/kg WB; (ii) WBD10, 100 g/kg WB and 50 g/kg DB; (iii) WBD5, 50 g/kg WB and 100 g/kg DB; and (iv) DB15, 150 g/kg DB. In Exp. 1, the apparent ileal digestibilities of total essential amino acids were higher (P < 0.05) in WB10 treatment than DB20. For Exp.2, the WB15 and WBD10 had higher pH and lower cooking loss (P < 0.05) than other two treatments. The WB15 treatment decreased (P < 0.05) the contents of palmitic acid (C16:0) in Longissimus dorsi muscle than WBD5 and DB15 treatments. In conclusion, it is suggested that water‐soaked barley improved some amino acid digestibility and the cooking loss and moderate fatty acid profiles in Longissimus dorsi muscle.  相似文献   

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本试验研究饲料肽对仔猪后期的生长、氨基酸利用率和肠道消化酶活性的影响.选用体重近似的96头(38±2)日龄的杜长大仔猪,随机分为4个处理组,每个处理4个重复.4个处理分别为:含6%鱼粉的对照组(C)、6%鱼粉和2%血浆蛋白粉的日粮组(T1)以及分别加1%和2%饲料肽等蛋白取代喷雾干燥血浆蛋白粉的试验日粮组(T2和T3),试验21 d结束时进行屠宰试验.结果表明:血浆蛋白粉和饲料肽可显著提高仔猪的平均日增重和日粮必需氨基酸消化率(P<0.05),二者之间的生产性能和日粮必需氨基酸消化率差异不显著(P>0.05).日粮处理对仔猪肠道消化酶活性没有显著影响(P>0.05).这表明饲料肤部分取代喷雾干燥血浆蛋白粉对仔猪后期的生长、氨基酸消化率和消化酶活性无显著影响.  相似文献   

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Two experiments were carried out using a balanced feed mixture composed of wheat, corn, soyabean meals, casein, and crystalline amino acids (AA) and supplemented with 0, 4, or 8% of apple pectin. The daily dietary allowance provided pigs with the same level of nutrients, apart from the pectin. One experiment was conducted on pigs (within 25 to 40 kg BW) with the post valve T-caecum (PVTC) cannula to determine AA digestibility and ileal digesta viscosity. In the second experiment, the N-balance was measured twice on male pigs at about 20 and 28 kg BW using 6 animals per diet and feed intake and body weight were measured twice during the 28 d. After 40 d of feeding the diets, the pigs were sacrificed and the small intestines were weighed and sampled. The added pectin decreased standardized ileal AA digestibility (on average up to 5% dig. units) and increased digesta viscosity from about 1 to 88 mPa s. The higher pectin level did not affect motility of the duodenum and mid-jejunum, measured as responses to electrical field stimulation and to acetylcholine. However, the response of the duodenum to electrical field stimulation was after feeding the diet with 4% pectin increased compared with other diets. Pectin supplementation did not alter the weight and the length of the small intestine, but induced changes in the intestinal morphology. Muscle layer width increased significantly in the duodenum, the mid-jejunum, and the ileum while villi length increased in the duodenum and ileum. The addition of pectin decreased N retention and increased the F/G ratio but did not affect significantly the ADG of the pigs.  相似文献   

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This study was conducted to investigate the effects of dietary rapeseed meal (RSM) inclusion levels on growth performance, organ health and standardized ileal amino acid digestibility (SIAAD) in meat ducks from 15 to 35 days of age. Six hundred and eighty 15‐days‐old ducks were randomly allotted to five treatments based on body weight. Five isonitrogenous and isoenergetic diets were formulated on a digestible amino acid basis by replacing 0% (the control), 25%, 50%, 75% and 100% (based on fresh) of protein from soya bean meal (SBM) with protein from RSM. The corresponding levels of RSM in experimental diets were 0%, 6.66%, 13.32%, 19.98% and 26.64% respectively. With increasing dietary RSM levels, body weight (BW) and average daily gain (ADG) linearly decreased (p < 0.001), whereas feed‐to‐gain ratio (F: G) linearly increased (p = 0.0078). Ducks fed the diets with 13.32% or more RSM had significantly lower (p < 0.05) BW, ADG and ADFI, or higher F: G than ducks fed the control diet. The maximum limit of dietary RSM supplementation was estimated to range from 4.27% to maximize ADG for 15 to 35 days to 11.69% to maintain feed intake for 15 to 35 days on the basis of a broken‐line model. At day35, the 4th primary wing feather length and SIAAD (except for Met, Thr and Val) linearly decreased (p < 0.001), and the thyroid glands weight (% of BW) linearly increased (p < 0.05) with increasing dietary RSM levels. Ducks fed the RSM inclusion diets had significantly lower (p < 0.0001) serum aspartate aminotransferase (AST) and alanine transaminase (ALT) activities than ducks fed the control diet. These results suggested that the maximum limit of dietary RSM containing 7.57 μmol/g glucosinolates was estimated to be 4.27% to avoid growth reduction.  相似文献   

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本文旨在研究小麦型日粮中添加木聚糖酶和植酸酶对肉鸡生长性能、回肠氨基酸表观消化率及矿物元素沉积的影响。试验选择1日龄科宝白羽肉仔鸡850只,随机分成5组,每组5个重复,每个重复34只鸡。一共有5种日粮,即低磷日粮、高磷日粮、低磷日粮+2000 IU/kg木聚糖酶、低磷日粮+500 FTU/kg植酸酶,低磷日粮+2000 IU/kg木聚糖酶+500 FTU/kg植酸酶,试验进行21 d。低磷组较高磷组显著降低了肉鸡的日增重、日采食量及趾骨灰分含量(P <0.05),与低磷组相比,木聚糖酶组显著降低了肉鸡的料比(P <0.05),而植酸酶组显著提高了肉鸡日增重、日采食量、趾骨灰分及饲料利用率(P <0.05)。复合酶组显著提高了15种氨基酸回肠表观消化率(P <0.05)。与低磷组相比,木聚糖酶组显著提高了表观消化能和可消化代谢能及回肠氮消化率(P <0.05),而植酸酶显著提高了氮沉积及回肠氮消化率(P <0.05),复合酶组显著提高了代谢能、可消化代谢能及氮沉积量(P <0.05)。植酸酶和复合酶组较高磷组显著提高了磷表观消化率和沉积量(P <0.05),但低磷组较高磷组显著提高了钙的表观消化率(P <0.05),植酸酶酶和复合酶组较其他3组显著提高了钾的沉积量(P <0.05)。结论 :小麦型日粮同时添加植酸酶和木聚糖酶对肉鸡生长和消化的影响要优于单独添加这两种酶。  相似文献   

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One hundred and twenty pigs were used to evaluate the effects of different dietary lysine levels on the growth performance, apparent nutrient digestibility, and abundance of cationic amino acid transporter messenger RNA (mRNA) in the small intestine of finishing pigs. Pigs received a low lysine diet (LL, 0.60% lysine), moderate lysine diet (ML, 0.80% lysine) or a high lysine diet (HL, 1.00% lysine) for 28 days. A digestion test was carried out during the third week. Although the apparent nutrient digestibility in pigs fed experimental diets were different (P < 0.05) and the highest when pigs were fed ML diet, diets did not change the growth performance. In the duodenum, mRNA abundance of PepT-1, as detected by real-time RT-PCR, was reduced in the LL diet (P < 0.05). A greater abundance of b0,+AT and PepT-1 mRNA was associated with the ML diet (P < 0.05) in the jejunum and ileum, respectively. In the ileum, the HL diet had a lower abundance of CAT-1 mRNA compared with other diets. These results showed that the finishing pigs would gain better nutrient digestibility when the dietary lysine content was 0.80%, and dietary lysine levels influenced the expression of cationic amino acid transporter mRNA in the small intestine of finishing pigs.  相似文献   

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