喹乙醇在鸡体内的毒物动力学及其生化毒性和病理学研究

本文对１３只健康ＡＡ鸡单次内服喹乙醇中毒剂量（１２０ｍｇ／ｋｇ）作了毒物动力学分析。用乙腈—乙酸乙酯混合溶剂提取血浆中的喹乙醇,反相高效液相色谱法（ＨＰＬＣ法）测定浓度。喹乙醇内服给药的药时数据适合一级吸收二室开放模型。毒物动力学主要参数为：ｔ１／２Ｋａ０．６３±０．２６ｈ,ｔ１／２α１．１２±０．３４ｈ,ｔ１／２β７．２６±３．０２ｈ,Ｋｅ０．５９±０．１５ｈ－１,Ｔｍａｘ１．１９±０．３１ｈ,Ｃｍａｘ７１．４０±１２．８１μｇ／ｍｌ,ＡＵＣ２５８．１２±３６．１１ｍｇ／Ｌ．ｈ。本试验表明,内服中毒剂量的喹乙醇在ＡＡ鸡体内的吸收、分布均很迅速,但消除缓慢;给药后２４ｈ,血药浓度均高于０．２μｇ／ｍｌ     

克伦特罗在猪体内的生物利用度及药物动力学研究

６头体重４７．００±４．５７ｋｇ（Ｘ±Ｓ）的健康长白和大白杂交猪，拉丁方设计试验，按４ｍｇ／ｋｇ静注、肌注和内服克伦特罗，高效液相色谱法检测血浆中药物浓度，ＭＣＰＫＰ药代动力学程序处理药时数据。静注给药的药代动力学参数是：ｔ１／２α０．６２±０．１２ｈ，ｔ１／２β４．８７±１．５６ｈ，Ｖｄ（ａｒｅａ）４．４８±０．５６ｌ／ｋｇ，ＣｌＢ０．６３±０．１１ｌ／ｋｇ／ｈ，ＡＵＣ６．３９±１．２７μｇ／ｍｌ．ｈ。肌注给药的药动学参数是：ｔ１／２Ｋａ０．２２±０．１０ｈ，ｔ１／２α０．５６±０．２１ｈ，ｔ１／２β４．２５±１．１０ｈ，ｔｍａｘ０．６０±０．１３ｈ，Ｃｍａｘ１．２７±０．３５μｇ／ｍｌ，ＡＵＣ５．４８±１．２９μｇ／ｍｌ．ｈ，Ｆ８５．４０±４．６９％。内服给药的药动学参数是：ｔ１／２Ｋａ０．２８±０．１５ｈ，ｔ１／２Ｋｅ３．１５±０．３６ｈ，ｔｍａｘ１．４６±０．１９ｈ，Ｃｍａｘ０．６５±０．１３μｇ／ｍｌ，ＡＵＣ３．９３±０．９９ｍｇ／ｌ．ｈ，Ｆ６１．０２±１０．９０％。肌注给药的生物利用度与内服比较，差异极显著（Ｐ＜０．０１）。     

恩诺沙星及其活性代谢物在鸡体内的药物动力学

为全面了解恩诺沙星在鸡体内的动力学过程与药效的关系进行了本研究。用反向高效液相色谱法测定鸡血浆中的药物质量浓度,所得恩诺沙星ｃｉ－ｔｉ数据用ＭＣＰＫＰ计算机程序处理,代谢物环丙沙星的ｃｉ－ｔｉ数据用代谢物动力学方法处理。静注恩诺沙星后的ｃｉ－ｔｉ数据符合二室开放模型,主要动力学参数：ｔ１／２α（０．２５±０．０４）ｈ,ｔ１／２β（５．２６±０．８１）ｈ,Ｖｄ（４．５３±１．０７）Ｌ／ｋｇ,ＣＬＢ（０．６１±０．１１）Ｌ／（ｋｇ·ｈ）,ＡＵＣ（１７．３９±３．９２）ｍｇ／（Ｌ·ｈ）。内服恩诺沙星的ｃｉ－ｔｉ数据,符合有吸收因素二室模型,主要动力学参数ｔ１／２ｋａ（０．４４±０．１１）ｈ,ｔ１／２α（１．１５±０．３８）ｈ,ｔ１／２β（９．１４±１．４５）ｈ,ＡＵＣ（１２．４８±２．３６）ｍｇ／（Ｌ·ｈ）,ｔｍａｘ（１．７７±０．２１）ｈ,Ｃｍａｘ（１．４４±０．３１）ｍｇ／Ｌ,Ｆ７２．１８％。试验结果表明,鸡静注与内服恩诺沙星后,代谢物环丙沙星的生成及消除缓慢、分布广泛,是影响恩诺沙星疗效的重要因素。     

氯羟吡啶在鸡组织中的残留研究

本文报道用高效液相色谱法检测肉鸡肌肉和肝脏组织中氯羟吡啶的残留。肉鸡肌肉和肝脏组织经乙腈提取，用氧化铝柱和葡聚糖凝胶阴离子交换柱净化分离，洗脱液浓缩后用含内标物的甲醇溶解。以磷酸盐缓冲液／乙腈（８５／１５，ｖ／ｖ）作为流动相，苯甲酰胺作为内标物，用ＲＰ－１８柱（２２０×４．６ｍｍ）在紫外波长２７０ｎｍ处检测。将氯羟吡啶以０．０５、０．１０和０．５０μｇ／ｇ分别添加到空白肌肉组织中，测得肌肉组织回收率为８８．０％、９０．４％和９１．６％；以０．１０和０．５０μｇ／ｇ水平添加到肝脏组织中，肝脏组织回收率为８５．４％和９０．２％，变异系数均低于１０％。用该方法测定肌肉和肝脏组织中氯羟吡啶残留的最低检测限分别为０．０２５ｍｇ／ｋｇ和０．０５ｍｇ／ｋｇ。经１２５ｍｇ／ｋｇ氯羟吡啶混料饲喂ＡＡ肉鸡，停药当天（０ｄ）测得肉鸡肌肉和肝脏组织残留量为２．８５ｍｇ／ｋｇ和７．０６ｍｇ／ｋｇ。停药７ｄ时测得肌肉和停药１０ｄ时测得肝脏组织残留量分别低于０．０２５ｍｇ／ｋｇ和０．０５ｍｇ／ｋｇ。     

鸡静注,肌注及内服氟哌酸的药物动力学研究

选用４２只健康ＡＡ鸡，分３组（每组１４只）进行药物动力学研究：静注、肌注及内服的剂量均为１０ｍｇ／ｋｇ。用二氯甲烷提取血浆中的药物，反相高效液相色谱法测定血浆氟哌酸的浓度，测定时以吡哌酸为内标。所得药物一时间数据用ＭＣＰＫＰ计算机程序处理，静注给药拟合二室开放模型，主要动力学参数是：ｔ１／２α０．１４±０．０８ｈ，ｔ１／２β３．６５±１．０３ｈ，Ｋｅ０．８８±０．４０ｈ－１，Ｖｄ３．８１±０．９８Ｌ／ｋｇ，ＡＵＣ１４．１４±３．２９μｇ／ｍｌ．ｈ。内服和肌注给药均适合具有一级吸收二室开放模型，肌注的主要动力学参数是：ｔ１／２ｋａ０．２２±０．１０ｈ，ｔ１／２α１．０３±０．６５ｈ，ｔ１／２β６．８７±２．８６ｈ，Ｋｅ０．２８±０．１０ｈ－１，ＡＵＣ９．８６±２．８８μｇ／ｍｌ．ｈ，Ｆ６９．７８％。内服的主要动力学参数是：ｔ１／２ｋａ０．６９±０．２３ｈ，ｔ１／２α１．７６±０．８９ｈ，ｔ１／２β１０．４３±３．２２ｈ，Ｋｅ０．２１±０．０５ｈ－１，ＡＵＣ８．５６±１．３６μｇ／ｍｌ．ｈ，Ｆ６０．５２％。鸡静注、肌注、内服氟哌酸的药动学特征是吸收较快，在体内分布广泛、半衰期较长。     

烟酸诺氟沙星在猪,鸡体内的组织残留研究

本文报道了烟酸诺氟沙星在猪、鸡体内的组织残留研究结果，猪、鸡均按１０ｍｇ／ｇ剂量给药，采用ＨＰＬＣ法测定肝、肾、肌肉中诺氟沙星浓度。猪肌注给药后７２小时，肾。肌肉中药物浓度已低于仪器最低检测限（０．０５μｇ／ｇ），肝中仍能检出少量药物，浓度为０．３０５±０．１６９μｇ／ｇ；鸡口服给药后４８小时，肝、肾、肌肉中药物浓度均已低于最低检测限。根据本试验结果，建议猪、鸡使用烟酸诺氟沙星后休药期为６天和２天。     

洛克沙胂对生长猪生长性能的影响

本试验研究日粮中添加不同剂量的洛克沙胂（４０ｍｇ／ｋｇ、５０ｍｇ／ｋｇ）、喹乙醇（５０ｍｇ／ｋｇ）和洛克沙胂（５０ｍｇ／ｋｇ）＋喹乙醇（５０ｍｇ／ｋｇ）对生长猪生长性能的影响。试验结果表明,不同剂量洛克沙胂组、喹乙醇组及洛克沙胂＋喹乙醇组的日增重明显优于对照组（Ｐ＜０．０５）;４０ｍｇ／ｋｇ与５０ｍｇ／ｋｇ洛克沙胂和５０ｍｇ／ｋｇ喹乙醇＋５０ｍｇ／ｋｇ洛克沙胂三组的料肉比也显著的低于对照组（Ｐ＜０．０５）;从经济效益上分析,生长猪日粮中添加４０ｍｇ／ｋｇ洛克沙胂的经济效益较好。     

氧氟沙星饮水治疗鸡败血霉形体—大肠杆菌感染的药代动力学分析

选用３２０只３３日龄石岐杂健康鸡，分成健康对照、感染对照、氧氟沙星中剂量和高剂量４组。感染鸡接种霉形体和大肠杆菌后，中剂量和高剂量组分别以１００ｍｇ／Ｌ和２００ｍｇ／Ｌ氧氟沙星饮水给药，在试验开始后２～５ｄ，每次给药后２ｈ和８ｈ剖杀，采用ＨＰＬＣ测定血药浓度。结果，血药浓度在中剂量组分别为（１．２６±０．３２），（０．７５±０．２３）ｍｇ／Ｌ，高剂量组分别为（１．６８±０．４２），（１．３５±０．０４）ｍｇ／Ｌ，中、高剂量组在给药后２～５ｄ平均血药浓度分别为（１．０１±０．２７），（１．５２±０．２１）ｍｇ／Ｌ。停药后血药消除缓慢，两组ｔ１２分别为３．１１，４．３３ｈ，ＡＵＣ为４．７６，６．４０ｍｇ·Ｌ－１·ｈ－１，Ｔｃｐ（ｔｈｅｒ）为２３．３４，２３．７２ｈ。本研究表明，氧氟沙星饮水给药对鸡霉形体和大肠杆菌合并感染具有显著的临床效果，从经济观点看，饮水给药以５０～１００ｍｇ／Ｌ，每天１次，连续４ｄ为好。     

氧氟沙星对实验性鸡大肠杆菌病的药效研究

以试管肉汤两倍稀释法测得氧氟沙星及氯霉素对鸡大肠杆菌的最小抑菌浓度分别为０．１及１．６ｍｇ／Ｌ，按５，１０和２０ｍｇ／ｋｇ的氧氟沙星及４０ｍｇ／ｋｇ的氯霉素分别给实验性鸡大肠杆菌病患鸡内服，每１２ｈ服药１次，共３ｄ。这些药物对鸡大肠杆菌病的治愈率分别为９０．０％，９３．３％，９６．７％及８３．３％，而感染对照鸡的死亡率为６３．３％。氧氟沙星和氯霉素的增重效果极显著高于感染对照鸡（Ｐ＜０．０１）。     

实用饲粮补锌对肉鸡组织锌、免疫器官及生产性能的影响

采用实用饲粮（玉米－多饼型,含锌３０ｍｇ／ｋｇ）,对狄高肉鸡（４～６周龄）分别补加锌４０和８０ｍｇ／ｋｇ,研究微量元素Ｚｎ对试鸡组织锌含量、免疫器官生长发育及生产性能的影响。结果表明饲粮缺锌（含Ｚｎ３０ｍｇ／ｋｇ）不影响鸡体重、饲料转化率和心、肝、肾、胰、肌胃、脑千克活体重（Ｐ＞０．０５）,但缺锌影响脾、胸腺、法氏囊、盲肠扁桃体、免疫器官及腺胃、小肠厚度、甲状腺生长发育（Ｐ＜０．０５或Ｐ＜０．０１）;饲粮补锌（４０、８０ｍｇ／ｋｇ）能改善免疫器官机能,增加胫骨、跗骨、趾骨、肝、胰、肾、心组织锌含量（Ｐ＜０．０５或Ｐ＜０．０１）;骨、肝、胰组织对饲粮锌缺乏较敏感,趾骨锌含量是标识鸡锌营养状况的灵敏指标。     

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.     

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.     

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.     

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.