邻甲酚酞比色法测定镁含量

镁是畜禽生长代谢过程中必需的常量矿物元素,国标法系用EDTA容量法依据用掩蔽剂掩蔽前(钙 镁)值和掩蔽后(钙)值的差测定饲料中镁含量,此法测定饲料中钙时准确性和重现性较差。而用邻甲酚酞比色法测定饲料中钙,准确、快速、简便(傅启高等,1996)。因此,我们用邻甲酚酞比色法进行饲料中镁含量的测定,研究是否适用。     

用邻—甲酚酞比色法测定饲料中钙含量的研究

用以邻—甲酚酞络合剂为显色剂的分光光度法测定了十五种常用饲料(包括牛奶和鸡粪)样品中的钙含量,并与用高锰酸钾法测定的钙值进行了比较。结果表明,用邻—甲酚酞比色法测定钙含量比用高锰酸钾法具有快速、灵敏、简便的特点。建议用邻—甲酚酞比色法作为营养分析中测定钙含量的常规方法。     

不同指示剂对EDTA法测定饲料中钙含量准确性影响的研究

EDTA法测定饲料中钙含量时,使用的指示剂有钙红指示剂、钙黄绿素-甲基百里香酚蓝指示剂(以下简称:钙黄绿素指示剂)两种。通过使用钙红指示剂、钙黄绿素指示剂对同种样品进行测定,结果显示:钙红指示剂法变异系数小,并且在滴定过程中颜色变化明显、易判断。     

三溴偶氮胂法测定饲料中钙

饲料中钙含量是饲料质量的一个重要指标 ,根据不同畜禽的生长需要 ,饲料标准中规定了各种畜禽饲料钙含量指标。钙过量 ,则会使日粮消化率降低 ;钙不足 ,则易使所饲畜禽患佝偻病、软骨病、母鸡产软皮蛋等病症。目前饲料中钙的测定主要采用高锰酸钾氧化还原滴定法、EDTA配位滴定法以及原子吸收分光光度法。但高锰酸钾性能不稳定 ,且操作烦琐费时 ;而EDTA法的测定结果偏差相对较大 ;原子吸收光度法也因仪器价格昂贵而难以普及使用。我们研究了三溴偶氮胂 (简写TBA)与钙的显色反应及条件 ,结果认为可用于饲料中微量钙的测定 ,操作简便、快…     

向氯偶氮安替比林光度法测定饲料中钙

间氯偶氮安替比林是一种对钙灵敏的显色剂,已分别用于岩矿、药物、水泥生料中钙的测定.目前,化学分析法测定饲料中钙通常采用高锰酸钾间接滴定法(国标方法)和EDTA配位滴定法,前者操作手续繁琐,检测时间长EDTA法虽具有快速、简便等特点,但方法的再现性和准确度比较差.笔者在文献基础上,进一步研究了饲料中钙与间氯偶氮安替比林的显色反应和条件,提出了饲料中钙测定的新方法.     

饲料中钙含量测定方法的比较

研究对比了几种测定饲料中钙含量的方法,分析了各方法的特点和适用范围。结果表明:用EDTA法测鱼粉、石粉和米糠的钙含量,与国标法测定结果比较差异不显著(P>0.05),而此方法测定玉米蛋白粉、豆粕、麦麸和玉米中的钙含量,测定结果却与国标法相比差异显著(P<0.05),说明EDTA法不适于测定钙含量在0.1%~0.4%之间的饲料,对钙含量低于0.1%和高于0.4%的饲料较适用。均相沉淀法和双氧水法与国标法测定结果比较,发现以上7种饲料的测定结果差异均不显著(P>0.05),且均相沉淀法适用于石粉类钙含量高的饲料的测定。钙色素法测定玉米蛋白粉、豆粕、麦麸和鱼粉的测定结果与国标法相比差异不显著(P>0.05),而玉米、石粉和米糠钙含量的测定结果与国标法比较却差异显著(P<0.05),说明钙色素法适用于钙含量中等的饲料的测定,不适合测定石粉、玉米、米糠类钙含量较高或较低的饲料。     

浅析高锰酸钾方法测定饲料中钙含量的注意事项

正测定饲料中钙含量的国家标准方法是高锰酸钾法《GB/T 6436-2002饲料中钙的测定》,该方法适用于饲料原料和饲料产品中钙含量的测定,其测定原理是将饲料中有机物破坏,钙变成溶于水的Ca~(2+)离子,用草酸铵定量沉淀,用高锰酸钾标准溶液间接滴定钙含量。     

宁夏利通区奶牛干奶期钙、磷盈亏状况调查

在对宁夏吴忠市利通区 4个奶牛场和 10户养牛户进行奶牛干奶期钙、磷营养状况调查中 ,分别测定了饲料中钙、磷含量 ,奶牛干奶期血清中钙、磷、羟脯氨酸、碱性磷酸酶、甲状旁腺素、降钙素含量。结果表明 :奶牛饲料中钙含量除小户基本正常 ,大户磷含量明显偏低 ,钙、磷比例失衡 ;散户日粮钙不足 ,小户钙、磷盈亏状况良好。血钙与碱性磷酸酶呈中度负相关 ,与甲状旁腺素呈中度正相关 ,相关系数分别为 - 0 .48(P<0 .0 42 )和 0 .48(P<0 .0 44 )。降钙素处于正常水平范围之内 ,平均值为 7.80± 8.16 pmol/l,95 %的置信区间为 3.75～ 11.86 pmol/l     

柱前紫外衍生—高效液相色谱法测定川贝母生物碱贝母素甲的含量

目的:建立川贝母生物碱贝母素甲的柱前紫外衍生—高效液相色谱法的测定方法。方法:以对甲苯磺酰氯为衍生试剂,在60℃的水浴条件下对贝母素甲水浴加热回流,采用HPLC-UV法测定川贝母中贝母素甲的含量。结果:在流动相为1 ml/min的甲醇—水(60∶40,v/v),柱温为35℃,检测波长为240 nm。贝母素甲在0.05～2.50μg/ml范围内线性相关系数为0.9993,方法检出限为0.008μg/ml和定量限为0.017 mg/ml,方法加标回收率为95.67%～100%,方法精密度(n=6)为2.4%。结论:本方法快速简便、灵敏度高、准确性好,适用于川贝母生物碱贝母素甲的含量测定。     

双波长吸光度差法测定饲料钙

本文提出了饲料中钙的测定新方法,研究了对乙酰基偶氮胂与钙的显色反应。结果表明,在 pH10.7的氢氧化钠介质中形成 1:2稳定的蓝色络合物;以 520nm为参比波长,630nm为测定波长,用双波长吸光度差法测得ξ520- 620= 2.1×104 ,钙量在 0- 3μg /25ml范围内,符合比耳定律。本方法用于饲料样品及饲料原料的测定,结果与国家标准基本一致,并明显优于 EDTA配位滴定法。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

A brief history of the prevention of infectious diseases by immunisations

Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.     

Micronutrient Content of Certain Tropical Conventional and Unconventional Feed Resources of Southern India

The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

Bovine Mastitis in Selected Areas of Southern Ethiopia

A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.     

不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响

本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。     

Microsporidial keratopathy in two dogs

A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.