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1.
研究了不同施肥处理和刈割日期对杂交狼尾草Ca、P和Mg含量的影响及其与家畜营养的关系,结果表明,有机肥的施用显著降低了植株Ca含量,对植株P和Mg含量无显著影响;随无机氮施用水平的提高,杂交狼尾草植株Ca和Mg含量显著提高,P含量显著降低;植株Ca、Mg含量均随刈割日期的推迟而显著提高,植株磷含量随刈割日期的推迟呈先降后升的规律;根据NRC推荐的饲养标准(奶牛、肉牛和绵羊),所有处理杂交狼尾草植株Mg含量均能满足家畜的需要,Ca:P为(0.95~2.67):1;利用杂交狼尾草饲喂高产奶牛时,应注意日粮中Ca、P的添加.  相似文献   

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《饲料广角》2006,(22):38-40,46
Hisardale雄性绵羊(24只,4 ̄5月龄)饲喂1个月,使体内矿物质水平基本一致。饲喂1个月后屠宰6只,体内器官抽样测定矿物水平,剩下18只羊根据体重分为3组,每组6只。3组试验日粮矿物水平(Ca、P、Zn和Mn)分别是NRC(1985)的100%(T1)、110%(T2)、120%(T3),饲喂120d。每月采集血液和羊毛。试验后期,进行5d的代谢平衡试验研究矿物元素在体内的沉积,发现额外补充矿物元素对干物质采食量无明显影响。T2、T3组日增重明显高于T1组(P<0.01)。T2(8.72kg)和T3(8.47kg)组的个体采食干物质量比T1组(10.81kg)低。T2和T3组干物质和粗蛋白质的消化率比T1组明显提高(P<0.05)。由于T2和T3组补充了矿物元素(钙、磷、硫、锌和锰),吸收率提高(P<0.01),铜吸收率降低(P<0.01),矿物元素(钙、磷、硫、锌和锰)供应量超过推荐水平可提高增重和饲料转化率。因此,在传统饲养水平下,额外补充缺少的元素(钙、磷、硫、锌和锰)10%对Hisardale雄性绵羊有利。  相似文献   

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Angus x Hereford heifers (n = 50) were randomly assigned to bahiagrass pastures treated with biosolids varying in mineral content and evaluated for mineral status, with special attention to Cu. Biosolids and NH4NO3 were all applied at the rate of either 179 kg N/ha (X) or twice this (2X). Fertilizer was applied to .81-ha pastures for the following treatments: 1) Baltimore biosolids (1X = 179 kg N/ha); 2) Baltimore biosolids (2X = 358 kg N/ha); 3) Tampa biosolids (1X = 179 kg N/ha); 4) Tampa biosolids (2X = 358 kg N/ha); or 5) control NH4NO3 (1X = 179 kg N/ha) applied at two times. Pastures were divided into five blocks with each treatment represented once in each block. Copper loads varied from 8.8 to 42.2 kg/ha, and Mo loads varied from .27 to 1.11 kg/ha. Heifers (two per pasture) grazed their assigned pastures exclusively for 176 d. Liver biopsies were taken from all animals at d 1, 99, and 176, and blood samples on d 1, 50, 99, 135, and 176. Liver and plasma were analyzed for selected mineral contents, and blood was analyzed for hemoglobin and hematocrit. Experimental animals were generally low in mineral status when assigned to pastures and deficient in Se and P. By d 50, plasma Ca, Mg, Se, P, and Zn were adequate for all treatments. Plasma Cu declined (P < .03) for all treatments from d 50 to 176. Plasma Cu reflected depleted liver Cu storage, with the two Tampa and highest Baltimore treatment means lower in plasma Cu than the control at 176 d. Liver Fe concentrations were adequate for all treatments, and Mo concentrations (< 2.18 mg/kg) did not approach levels indicative of toxicity. Liver Cu declined (P < .05) with time for all treatments. By d 99, animals receiving the two Baltimore treatments and the lowest Tampa application rate had lower (P < .05) liver Cu than the control, and all treatments were lower at 176 d. The decline of animal Cu status (liver and plasma) reflects the low Cu status of bahiagrass and the possibility of high forage S (.30 to .47%) interfering with Cu metabolism. Forage Mo was low but was slightly higher in biosolids-treated pastures. High levels of biosolids applications to bahiagrass pastures were not detrimental to mineral status except Cu, which had a tendency to decline in plasma and for all biosolids treatments declined in liver.  相似文献   

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长期使用抗生素会引发耐药菌的产生,对动物和人的健康带来安全隐患,因此,研究开发新的天然饲料添加剂成为近年来的热点。本文讨论了植物及植物提取物(单宁、挥发油等)对反刍动物生产性能及消化,特别是对瘤胃发酵作用方式的影响。  相似文献   

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施肥对喀斯特地区植草土壤碳库管理指数及酶活性的影响   总被引:2,自引:0,他引:2  
为了解施肥对喀斯特地区土壤有机碳积累及平衡的影响,通过田间试验,研究不同施肥处理对植草土壤活性有机碳含量、碳库管理指数及土壤酶活性(淀粉酶、蔗糖酶和脲酶)的影响。结果表明,施肥对植草土壤活性有机碳和碳库管理指数的影响显著,但是对3种土壤酶活性的影响不一致。与不施肥相比,施肥提高土壤活性有机碳和碳库管理指数,以N2PK处理提高土壤活性有机碳含量最为明显,提高幅度达到695.6%;低N(N1)处理提高土壤淀粉酶活性8.65%~13.80%,而高N(N2)处理提高土壤淀粉酶则不明显,且N2P处理降低17.94%;各施肥处理土壤蔗糖酶活性降低2.55%~26.97%;单施氮肥和N2P处理提高土壤脲酶活性87.67%~169.03%,而N1P处理降低土壤脲酶活性。研究结果可为喀斯特地区牧草科学施肥及农田固碳减排提供理论依据。  相似文献   

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采用品种(青燕1号、青海444、青海甜燕麦、林纳)、施肥水平(不施肥、尿素+磷酸二铵、尿素+磷酸二铵+有机肥、有机肥)和混播水平(0 kg/hm~2、45 kg/hm~2、60 kg/hm~2、75 kg/hm~2)3因素4水平正交试验设计,探讨3个因素影响下燕麦人工草地生物量季节动态。结果表明:3个因素显著影响燕麦与箭筈豌豆混播人工草地各器官的生物量。品种在整个生育期影响燕麦茎和穗生物量的积累,并对燕麦生长前期地下和生长后期地上生物量的积累有影响;施肥水平在整个生育期影响叶生物量的积累,并对燕麦生长前期地上和后期地下生物量的积累有影响;混播水平在整个生育期主要影响箭筈豌豆地上生物量、茎和叶生物量的积累。燕麦和地上总生物量积累的关键时期在抽穗—开花期,箭筈豌豆地上生物量积累的关键时期在开花—乳熟期。燕麦茎在整个生育期生物量持续显著增加,而叶和穗生物量增加较平缓;箭筈豌豆茎和叶生物量在生长前期(燕麦开花期前)增长比较平缓,而开花—乳熟期增长迅速。地下生物量显著增加到开花期后基本趋于稳定。3个因素影响下,燕麦人工草地地上和地下生物量均以青海甜燕麦、尿素+磷酸二铵+有机肥施肥处理、75 kg/hm~2混播水平下最高,平均分别为697.71,662.27、630.54 g/m~2和82.27,82.08和81.25 g/m~2。  相似文献   

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Four trials were conducted to determine the effects of adding various levels and types of fat to dry-rolled corn (DRC) finishing diets containing 0 or 7.5% forage. In Trial 1, 88 yearling steers (mean BW = 352 +/- 38 kg) and 176 heifers (mean BW 316 +/- 15 kg) were blocked by sex and weight into four replications. Treatments were 0, 2, 4, or 6% (DM basis) bleachable fancy tallow (BT) fed with 0 or 7.5% (DM basis) forage. Addition of BT to the 7.5% forage diet had no effect on ADG or gain/feed (G/F). However, adding BT to the all-concentrate diet decreased ADG (linear, P < .01) and G/F (linear, P = .08). In Trial 2, 184 yearling steers (mean BW = 347 +/- 21 kg) and 144 heifers (mean BW 322 +/- 8 kg) were blocked by sex and weight into six replications. Fat treatments were 0% fat, 4% BT, or 4% animal-vegetable oil blend (A-V); each fat treatment was fed with 0 or 7.5% forage. Across forage levels, the addition of fat increased (P < .01) ADG and G/F for cattle fed DRC. In Trial 3, 18 crossbred wether lambs (mean BW = 44.4 +/- 2.5 kg) were fed DRC and 7.5% forage and allotted randomly to the same fat treatments fed in Trial 2. Apparent total tract fat digestibility increased (P < .01) with the addition of BT or A-V. In Trial 4, 40 crossbred wethers (mean BW = 25 +/- 4.1 kg) and 16 ewes (mean BW = 23 +/- 2.7 kg) were individually fed 7.5% forage diets containing 0, 1, 2, or 4% BT. Addition of BT increased (linear, P = .10) G/F. In summary, fat addition to DRC finishing diets fed to yearling cattle did not consistently affect gain/feed, feed intake, and ADG.  相似文献   

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The effect of sulfate in drinking water at concentrations of 600, 1,200, and 1,800 mg/L on nursery pig performance and health was evaluated over 28 days on 415 weaned pigs. Sodium sulfate and magnesium sulfate were evaluated in combination at concentrations of 600, 1,200, and 1,800 mg/L, and independently at concentrations of 600 and 1,800 mg/L in the drinking water. Seven treatment groups and 1 control group were evaluated for mean gain, feed consumption, water consumption, feed conversion, prevalence of diarrhea, and evidence of common post-weaning enteric pathogens. Statistical analysis was performed, using analysis of variance with repeated measures including initial pig weight as a covariate. Prevalence of diarrhea was analyzed nonparametrically with a repeated measures design. Results indicated that pigs drinking 600, 1,200, or 1,800 mg of sulfate/L water had increased prevalence of nonpathogenic diarrhea during the trial period. There was a trend for increased water consumption corresponding to increased sulfate in the water. Differences in mean daily gain, feed consumption, or feed-to-gain ratios were not observed. Forty-five pigs were treated at least once during the trial and 4 pigs died, resulting in a nursery morbidity of 11% and mortality of 0.96%. Fourteen isolates of enterotoxigenic Escherichia coli were found and rotavirus was isolated from 1 pig. Pigs in this study were not exposed to transmissible gastroenteritis virus. Except for an increase in fecal moisture content (not associated with pathogenic diarrhea), concentrations of up to 1,800 mg of sodium, magnesium, or a combination of sodium and magnesium sulfate/L had no adverse effect on nursery pig performance.  相似文献   

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采用N、P、K三因素肥料试验研究顾氮磷钾肥配施对退化人工草地的增产效应以及土壤养分含量的影响。结果表明,NPO处理与单施N肥处理比较,1998年黑麦草增产99.0%,鸭茅增产2.5%,白三叶增产162.%;2000年则为219.1%、14.6%和78.3%。在施用氮肥基础上,施用磷肥增产效果更为突出。在南方红壤退化人工草地中,由于土壤长期侵蚀的影响,土壤磷素已经退化到“谷底”水平,而投入系统中的磷素一部分被铁铝氧化物所固定,另一部分通过刈割或采食被带出系统,磷素损失量高。因此,在退化人工草地中首要的养分限制因子是磷,其次为钾。提高土壤,pH,降低红壤固磷能力,提高磷肥肥效是改良退化红壤人工草地的重要施肥技术措施。  相似文献   

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1. In a 42-d feeding trial, 264 one-d-old, as hatched, Cobb 400 broiler chickens (6 pens per group, n = 11 per pen in a 2?×?2 factorial arrangement) were fed on two concentrations of dietary calcium (Ca) (9.0 and 7.5 g/kg in starter, 7.5 and 6 g/kg in grower phases) and supplemental phytase (0 and 500 U/kg diet).

2. During d 0–21, the high Ca + phytase diet improved body weight. During d 0–42, feed intake was increased by the low Ca diet and decreased by phytase supplementation. Feed conversion ratio during d 0–21 was improved by the high Ca + phytase diet.

3. At d 42, Ca in duodenal digesta was reduced by low dietary Ca and supplemental phytase. High dietary Ca reduced P in duodenal and jejunal digesta. Phytase reduced digesta P and increased serum P concentration.

4. Relative tibia length decreased with low dietary Ca and increased with phytase. The robusticity index of tibia was improved by the low Ca diet and phytase supplementation. Phytase supplementation increased tibia ash and concentrations of Ca, magnesium (Mg), manganese (Mn), copper (Cu), zinc (Zn) and iron (Fe) in tibia. The low Ca diet increased Mg, Mn and Fe and reduced Cu and Zn in tibia.

5. It was concluded that 7.5 g Ca/kg during weeks 0–3 and 6 g Ca/kg during weeks 3–6 sustained broiler performance and bone ash, while phytase supplementation facilitated tibia mineralisation, particularly during the grower phase.  相似文献   

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研究测土配方施肥对葡萄生长期土壤理化性质及果实品质的影响,为葡萄土壤养分管理和可持续生产提供依据。以4年生“醉金香葡萄”为材料,设计了9个测土配方施肥处理,测定了各处理5个葡萄生长关键期的土壤速效氮磷钾含量及采后果实品质。与常规施肥相比,测土配方施肥能调节及维持土壤速效氮磷钾含量,而采取当地常规施肥方式将加速土壤速效氮含量的富集和速效磷、速效钾含量的缺乏;改进的Nemerow肥力综合指数法评价结果显示,试验前土壤综合肥力为1.53,土壤肥力为Ⅱ级,配方施肥能提高土壤综合肥力0.03~0.23,部分处理将土壤肥力提高至Ⅰ级,其中,配方施肥处理1的土壤肥力最高,为1.76,而常规施肥土壤肥力下降了0.15;此外,测土配方施肥能显著提高醉金香葡萄产量、单果重、可溶性固形物和总糖含量,降低总酸含量;试验数据表明,醉金香葡萄采取每公顷施鸡粪12000kg、过磷酸钙1800kg、尿素675kg、磷酸一铵600kg、硫酸钾1125kg综合效益最佳,不仅能增加葡萄产量,改善果实品质,还能平衡土壤氮磷钾营养元素含量,对土壤综合肥力的提高效果也最为显著。  相似文献   

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为了研究日粮的蛋白质和纤维水平对仔猪生产性能和健康状况的互作,特选择96头35日龄的仔猪(体重为9.11±0.60kg),分32个栏饲养,每栏3头,分成4个日粮处理组,饲喂期21d。在设定的2×2因子处理中,4种日粮以大米、奶制品和大豆粕为基础配制,日粮蛋白质设两个水平(15.4%与19.4%,风干基),纤维也设两个水平[低水平纤维(LF)为含5.3%中性洗涤纤维,高水平纤维(HF)为含7.15%中性洗涤纤维,风干基]。高水平纤维日粮组在基础日粮中添加了40g/kg的小麦麸和20g/kg的甜菜浆。每周测定动物生产性能,试验第1天和最后一天收集粪样进行微生物学分析,并且按1(液态)到4(硬实)的评分体系对粪便进行评分。在试验最后1d,每栏选1头猪采集血液,分析急性期反应蛋白(acute-phase protein)和主要急性期反应蛋白(major acute-phase prot)(即Pig-MAP)的含量,随后进行屠宰,对消化道(包括内容物)进行称重,并进行结肠组织学分析。饲喂高水平纤维日粮的仔猪具有较大的平均日增重(390g与457g,P≤0.001)和大肠重量(以占体重比例衡量为4.4%与5.4%,P≤0.05)。这与较高的短链脂肪酸浓度(尤其是乙酸和丁酸)、较少的大肠杆菌数量(每克粪便含7.77与6.86logcfu,P≤0.05)和较高乳酸杆菌与肠道细菌比(0.76与1.37,P≤0.05)是相符的。虽然日粮蛋白质水平没有改变猪的生产性能,但是20%的蛋白质水平提高(P≤0.05)了小肠(6.5与7.7)和大肠(3.8与4.3)的相对重量(占体重的百分比)。在大肠内,含20%蛋白质的日粮使仔猪杯状细胞数量增加(4.6/100与5.4/100μm;P≤0.05),并使肠上皮内淋巴细胞数量减少(1.8/100与1.3/100μm;P≤0.05)。在健康状况方面,提高日粮纤维水平所产生的效果与日粮中的蛋白质含量有关。在含16%蛋白质的日粮中增加纤维水平可降低粪便评分值、增加抗生素治疗次数,然而在?  相似文献   

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Interactions among grain type (grain sorghum, corn or wheat), roughage level and monensin level were studied in four feedlot trials using pen-fed crossbred yearling cattle. In Trial 1, cattle fed high-moisture corn (HMC) were more efficient (.1537 vs .1406 for gain/feed; P less than .01) than cattle fed dry-rolled grain sorghum (DRGS). As level (0, 3, 6, 9%) of dietary roughage was increased, feed efficiency (gain/feed) decreased (.1566, .1461, .1479, .1382; linear, P less than .01). In Trial 2, a grain type (DRGS; dry-rolled corn, DRC; dry-rolled wheat, DRW) x roughage level interaction was observed for daily gain and feed efficiency. Feed efficiency (gain/feed) was decreased when roughage was added to diets containing DRC (.1608 vs .1750) or DRGS (.1674 vs .1465), but not to the diet containing DRW (.1664 vs .1607). In trial 3, a grain type x roughage level x monensin level interaction (P less than .08) was observed for feed efficiency. The addition of 27.5 mg of monensin per kilogram of the 0% roughage-DRC diet tended to improve feed efficiency (.1633 vs .1531), but the addition of monensin to the 7.5% roughage-DRC diet tended to depress feed efficiency (.1476 vs .1575). The addition of either roughage (.1493 vs .1420) or monensin (.1500 vs .1413) to the DRW diet improved feed efficiency. In Trial 4, cattle fed a combination of 75% DRW and 25% DRC were more efficient (.1618 vs .1591; P less than .06) than cattle fed DRC. As level of roughage (0, 3.75, 7.5%) increased, feed efficiency decreased linearly (.1645, .1599, .1569; P less than .0001). Monensin had no effect on feed efficiency. The value of feeding roughage and monensin was variable both across grain types and within similar grain types.  相似文献   

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Two hundred and sixteen weanling gilts (6.65+/-0.08 kg) were used to determine the effects of decreasing supplemental concentrations of Zn, Cu, Fe, and Mn, and trace mineral source (inorganic vs. chelated) on growth performance, mineral status, and fecal mineral concentrations from weaning through development. The study was conducted over three trials with 72 pigs in each trial. Gilts were blocked by weight and randomly assigned to either 1) control, 2) reduced inorganic, or 3) reduced chelated trace minerals. The control diet was supplemented with 25, 150, 180, and 60 mg/kg of Cu, Zn, Fe, and Mn (in sulfate forms), respectively, during the nursery phase and 15, 100, 100, and 40 mg/kg of supplemental Cu, Zn, Fe, and Mn, respectively, during the growing and gilt-developer phases. Reduced inorganic and reduced chelated treatments were supplemented during all phases with 5, 25, 25, and 10 mg/kg of Cu, Zn, Fe, and Mn, respectively. The reduced chelated treatment supplied 50% of the supplemental Cu, Zn, Fe, and Mn in the form of metal proteinates, with the remainder from sulfate forms. Performance by control pigs did not differ from pigs fed the reduced trace mineral treatments during the nursery and grower-development periods. Gain:feed was lower (P < 0.05) for pigs fed the reduced inorganic compared with those fed the reduced chelated treatment during the nursery period. Trace mineral source did not affect performance during the growing or gilt-developer phase. Plasma Zn concentration and alkaline phosphatase activity were higher (P < 0.01) in control pigs than in those receiving reduced trace minerals during the nursery and growing phases. Plasma Cu concentration and ceruloplasmin activity were generally not affected by treatment. Hemoglobin concentrations were lower (P < 0.05) for the reduced inorganic compared with the reduced chelated treatment in the nursery phase. Fecal concentrations of Cu, Zn, and Mn were lower (P < 0.05) in pigs fed reduced trace minerals than in controls during all production phases. Fecal Zn concentration during the nursery and fecal Cu concentrations during the growing and gilt-developer phases were lower (P < 0.05) in pigs fed the reduced chelated compared with the reduced inorganic treatment. Results indicate that reducing the concentrations of Zn, Cu, Mn, and Fe typically supplemented to pig diets will greatly decrease fecal mineral excretion without negatively affecting pig performance from weaning through development.  相似文献   

18.
To compare the performance of steer calves managed under different stocking rates (SR; 3.7, 6.2, 8.6, and 11.1 steers/ha for 140 d; chi(I1)) and N fertilization rates (112, 224, and 336 kg of N/ha; chi(I2)) in May 1996, 1997, and 1998, 72 steer calves (BW = 231 +/- 2.5 kg) were assigned randomly to one of 12 0.81-ha dallisgrass (51%)/common bermudagrass (32%) pastures. One-third of the fertilizer was applied in the form of ammonium nitrate in May, June, and August to achieve the prescribed totals. Treatments were separated using a polynomial regression equation: gammai = beta0 + beta1chi(I1) + beta2chi(I2) + beta(11)chi2(I1) + beta(12)chi2(I2) + beta(12)chi(i1)chi(i2) + epsilonI, with years as replicates. Within the range of the data, ADG and BW gain per steer were greatest at a stocking rate of 3.7 steers/ha and 336 kg/ha of N. Body weight gain per hectare peaked at 701 kg when cattle were stocked at 8.9 steers/ha and the pasture was fertilized with 336 kg/ha of N. The least cost of production was at a stocking rate of 3.7 steers/ha, with 112 kg/ha of fertilizer N applied, and the greatest cost of production was at a stocking rate of 11.1 steers/ha with 336 kg/ha of fertilizer N applied. Fertilization at 336 kg/ha of N produced the most profitable stocking rate at 7.3 steers/ha and returned 355.64 dollars. The optimal stocking rate for net return was 79, 81, and 82% of that for maximum BW gain per hectare for 112, 224, and 336 kg/ha of N, respectively. Under the assumptions made in the financial analysis, these data show that the economically optimal carrying capacity of similar pastures can be increased with N fertilizer up to at least 336 kg/ha annually.  相似文献   

19.
为明确甘肃陇东地区苜蓿草地土壤矿质养分亏缺及牧草养分水平,对环县、合水、庄浪、泾川的苜蓿和土壤的N、P、K、Fe、Mn、Cu、Zn含量及其相关性进行研究。结果表明:试验区土壤N含量略高于我国平均水平、P含量低于我国平均水平,K素略低于我国平均水平;土壤矿质元素含量为有效Mn极富、有效Zn中等、有效Fe、Cu缺乏。苜蓿中N含量适中,P、Fe、Mn、Cu、Zn含量较低,K素含量高;苜蓿对K素需求量高于所测其他矿质养分;苜蓿微量元含量由高到低为FeMnZnCu,且苜蓿对Fe的需求高于Mn,Zn和Cu。土壤与苜蓿的全P含量极显著相关(r=-0.738,P0.01),全N含量显著相关(r=-0.522,P0.05),有效Fe含量显著相关(r=0.61,P0.05),有效Zn含量呈高度相关(r=0.742,P0.05);土壤与苜蓿全K、有效Cu、有效Mn含量未呈现出显著关系。  相似文献   

20.
Two experiments were conducted with chicks to examine the effect of high dietary levels of soluble sources of Zn on tissue Zn, Cu, and Fe concentrations as influenced by two methods of oral Zn administration from 14 to 21 d of age. Treatments included the basal diet (62 ppm Zn), basal diet supplemented with 1,000 ppm Zn from Zn sulfate, acetate, or chloride fed continuously, or basal diet plus crop intubation with a single oral dose of water (control) or 1,000 ppm Zn dietary equivalent from the sources based on feed intake from the previous day. In Exp. 2, crop-intubated doses were administered daily from 14 to 21 d of age. In Exp. 1, chicks given Zn by gavage decreased (P < .0001) feed intake at 24 h after oral dose compared with chicks fed either the control or high-Zn diets. After the gavage dosing stopped, feed intake was similar among treatments. Bone Zn was increased (P < .0001) by Zn source and was greater at 24 than at 168 h after dosing by gavage. In chicks given a single gavage dose of Zn, liver and kidney Zn measured at 24 h after oral dosing was greater (P < .0001) than at 168 h. In birds given a single oral dose of Zn, time x Zn source interactions were observed in pancreas (P < .0001), mucosal cells (P < .01), and remaining intestinal tract segments (P < .001). In Exp. 2, greater bone, pancreas, kidney (P < .0001), and liver (P < .001) Zn accumulations were observed in chicks given daily gavage doses of Zn compared with those fed Zn in diets. Zinc from the four sources was absorbed and stored in tissues to a similar extent.  相似文献   

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