共查询到20条相似文献，搜索用时 78 毫秒
1.
2.
3.
4.
5.
采用微波消解技术处理样品,用石墨炉原子吸收光谱法测定,对消解溶剂和微波条件进行了优化,研究了石墨炉原子吸收法的测定条件。结果表明,以HNO3+HClO4+H2O2作为微波消解溶剂效果最佳,在基体改进剂NH4H2PO4和Pd(NO3)2存在下,可有效地消除基体的影响,建立了微波-石墨炉原子吸收光谱法测定鱼粉中镉(Cd)和铬(Cr)的方法,Cd和Cr检出限分别为0.17ng/mL和0.46ng/mL;回收率分别为88.2%～94.1%(RSD:2.7%,n=6)、91.7%～106.2%(RSD:6.6%,n=6)。 相似文献
6.
畜禽的生长发育对硒的需求必不可少，但过量摄入也将引起畜禽中毒，因此在饲料及饲料原料对硒进行检测控制其含量是非常必要的。本文根据实际对饲料、饲料原料硒的测定，通过实验中加入不同的基体改进剂，以降低硒在灰化过程中的损失，以提高对硒测定准确度。 相似文献
7.
8.
试验采用高效液相色谱法测定饲料样品中色氨酸的含量。样品经过处理后,用Agilent C18(4.6 mm×150 mm,5μm)色谱柱分离样品,以0.008 5 mol/l的乙酸钠+甲醇=95+5为流动相;检测波长280 nm,流动相流速1.0 ml/min。结果表明,色氨酸在4.656~298μg/ml范围内,峰面积与其浓度线性关系良好(r=0.999 9),最低检测限为0.033 5μg/ml,两种饲料中色氨酸含量均在国标允许的误差范围内。方法准确、简便、快速,适用于色氨酸的含量测定。 相似文献
9.
96只"白来航"蛋鸡用于研究富含ω-3脂肪酸和天然抗氧化剂的配方饲料对蛋鸡蛋黄成分的影响。试验蛋鸡被随机分为4组:对照组(少量添加剂含量);FSE功能饲料组(150g亚麻籽+200mg维生素E+3g螺旋藻/kg饲料);FOSe功能饲料组(20g鱼油+0.2mg有机硒+3g螺旋藻/kg饲料)和FSE+FOSe功能饲料组(75g亚麻籽+10g鱼油+100mg维生素E+0.1mg有机硒+3g螺旋藻/kg饲料)。试验结果表明,这三种功能饲料都能增加蛋黄类胡萝卜素(P0.01)和ω-3脂肪酸的含量,饱和脂肪酸比例则下降,蛋黄脂质中油酸含量没有显著变化。这三种功能饲料能显著降低蛋黄胆固醇含量(P0.01)。各处理组鸡蛋煮后有可比的嗅觉感受。日粮中补充的硒和维生素E可协同作用增加鸡蛋中ω-3脂肪酸的含量。 相似文献
10.
20～700μg/ml的La(NO3)3处理的苜蓿种子吸水速率明显加快,膜的通透性增大,呼吸作用增强.其中,用500μg/ml La(NO3)3处理效果最佳,用1200～1500μg/ml La(NO3)3处理则抑制种子萌发. 相似文献
11.
12.
魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
13.
14.
本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
15.
REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
16.
17.
18.
Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
19.
20.
以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献