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氨气是一种有毒、无色、有强烈刺激性臭味的气体,可感觉最低浓度为5．3×10^-6。氨气的水溶解度颇高（0℃时1L水可溶907g）,故常被吸附在鸡的皮肤黏膜和眼结膜上,从而对其产生刺激并引发各种炎症。有资料称,当鸡舍内氨气浓度达20×10^-6并持续6周时, 相似文献
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<正>(接上期)通风换气的要求:1～2周龄以保温为主,可不开或少开换气扇。14日龄前切不可有风从鸡身上吹过。鸡舍内氨气浓度不大于10ppm,无烟雾、粉尘;2周龄以后应在保证适宜温度的情况下,加强通风换气。氨气浓度不大于20ppm;大鸡每小时换气量为:夏天50立方米/只,冬天20立方米/只。人对氨气浓度的感官指标及对肉鸡的影响:5～10ppm可嗅出氨气味;10～20ppm轻微刺激眼睛和鼻孔;开始对鸡产生伤害;20～30ppm较强刺激眼睛和鼻孔。大大提高了肉鸡呼吸道病的发生 相似文献
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冬季天气寒冷，气温较低，大多数养殖户都能注意到防寒保温的重要性。然而在保温的同时，往往忽视了通风换气，致使鸡舍内有害气体如氨、硫化氢、二氧化碳，特别是氨的浓度升高，严重时导致鸡氨气巾毒或引发其它疾病。 相似文献
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王建彬 《河南畜牧兽医(综合版)》2008,29(12):27-28
据有关研究资料表明,由于鸡对蛋白质饲料的利用率不高,饲料中50％-70％的氮以粪氮的方式排出体外,这些氮化合物轻微生物作用后生成氨气。氨气无色,刺激性臭味,易溶于水,并可挥发到大气中污染空气,严重时构成酸雨,别一部分则被氧化成硝酸盐渗入地下或随地表水流入江河,造成更广泛的污染。在鸡舍中,氨气常被溶解或吸附在潮湿的地面、墙壁及鸡的呼吸道黏膜上,引起咳嗽、气管炎和支气管炎、肺水肿等症状。高浓度的氨可直接刺激体组织,引起碱性化学性灼伤,使组织溶解、坏死,还能引起中枢神经麻痹、中毒性肝病、心肌损伤等症。鸡长期处在高浓度氨的环境中,体质变弱,对某些疾病的易感性增强,采食量、日增重、生产力都下降。鸡舍中氨气的最高浓度限定为20mg／kg。当空气中氨气浓度达到20mg／kg时,可引起鸡的角膜炎、结膜炎,使新城疫发病率大大增加;空气中氨气浓度达到50mg／kg时,能使呼吸频率下降,产蛋量减少。 相似文献
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1养殖场环境污染对家禽的影响
家禽粪便中的尿酸和未消化的蛋白质在微生物作用下生成氨气,可以直接危害饲养家禽的呼吸道,在氨气浓度较高的条件下,会引起家禽免疫机能下降。鸡对氨特别敏感,氨对鸡产蛋性能有严重的影响,当禽舍内氨气的浓度大于20.0毫克/升时,在这种环境中饲养6星期的鸡或者火鸡,即可出现肉眼可见的病理变化,而且鸡对新城疫病毒更易感; 相似文献
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氨气是一种刺激性很强的气体，能强烈地刺激鸡呼吸道黏膜和眼角膜。它主要来源于鸡排泄的粪便及鸡舍地面上潮湿垫料之中，当鸡粪在舍内长时间不清理，垫料严重潮湿，长时问不开窗通风换气，无排风设施等均可造成舍内氨气蓄积，使氨气浓度增大。氨气危害常发生在寒冷季节，尤其是育雏阶段，养鸡户往往偏重于对育雏舍的温度、湿度的要求，而忽视舍内有害气体含量对雏鸡的危害，特别是舍内温度达不到要求标准。 相似文献
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安得Ⅰ号在水产养殖上的应用 总被引：1，自引：0，他引：1
通过安得Ⅰ号（含稳定性二氧化氯）消毒剂以不同浓度对水产养殖中常见病原菌杀灭试验表明：该消毒剂浓度为0．25ppm，作用时间5分钟时，可以全部杀灭嗜水气单胞菌，非-01霍乱弧菌、迟缓爱德华氏菌和铜绿假单胞菌，在水簇箱水体中以0．5ppm浓度对嗜水气单胞菌杀菌率达99．98％；对欧鳗毒性试验表明其半致死浓度（TLM24）介于5～10ppm，TLM24＞5ppm。 相似文献
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氨气具有辛辣刺激性臭味，其比重为0．59，可感浓度为5．3毫克／千克，水溶性强。正常禽舍氨的浓度应低于25毫克／千克，此时即使嗅到氨的臭味，对鸡的生长也无大危害。当氨浓度超过25毫克／千克时，能刺激眼睛引起结膜炎，氨浓度达到75毫克／千克时，便可造成中毒，甚至死亡。氨气中毒于冬季及早春时节较为常见， 相似文献
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《饲料工业》2019,(18):54-58
应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。 相似文献
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In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum. 相似文献
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Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size. 相似文献
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液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估 总被引：1，自引：1，他引：0
采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度. 相似文献
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