两种组胺受体拮抗剂对肺动脉高压肉鸡右心功能的影响

探讨组胺H,受体拮抗剂扑尔敏和H。受体拮抗剂西咪替丁对低温诱发肺动脉高压肉鸡右心功能的影响,由此反证内源性组胺在低温诱发肉鸡肺动脉高压形成过程中的作用。采用160只17日龄AA肉鸡随机分为4组,每组40只。（1）常温组：在常温条件下饲养（22～23℃）,每天注射生理盐水2次;（2）低温组：低温环境中饲养（9～11℃）,每天注射生理盐水2次;（3）扑尔敏组：与低温组相同饲养,每天注射扑尔敏2次;（4）西眯替丁组：与低温组相同饲养,每天注射西眯替丁2次。分别于低温处理后1周（24日龄）、2周（31日龄）、3周（38日龄）、4周（45日龄）从每组中各随机抽取7只,利用右心导管法测定右心室内压和右心室压最大变化速率,计算腹水心脏指数（AHI）和右心衰竭率。剖杀后用常规阿尔新蓝法对心脏中肥大细胞（MC）染色,免疫组化方法显示组胺。结果：（1）低温处理后使肉鸡肥大细胞和组胺阳性细胞数量显著降低,但2种组胺受体拮抗剂对肥大细胞数量及组胺阳性细胞数无明显影响;（2）扑尔敏组肉鸡右心内压相对稳定,45日龄时右心室舒张压显著低于低温组（P〈0．05）。西咪替丁组肉鸡右心收缩压和舒张压处于较低水平,且在31和38日龄时显著低于低温组（P〈0．05）;（3）扑尔敏组右心内压最大变化速率相对稳定,31日龄时显著低于低温组（P〈0．05）,而45日龄时显著高于低温组（P〈0．05）。西咪替丁组右心内压最大变化速率处于较低水平;（4）45日龄时,扑尔敏组AHI显著低于低温组（P〈0．05）;（5）扑尔敏组显著（P〈0．05）降低了右心肥大指数和右心衰竭发生率,西咪替丁组仅显著（P〈0．05）降低了右心衰竭率。以上结果表明,内源性组胺可能通过H3受体介导肉鸡右心肥大和衰竭,从而促进肺动脉高压综合征的发生发展。     

扎鲁司特对低温诱发的肉鸡肺动脉高压的影响

将60只雄性艾维茵商品代肉鸡常规育雏，17日龄随机分为3组：常温对照组(常温组)、低温模型组(低温组)和低温扎鲁司特组(扎鲁司特组)。各组于处理后14d(31日龄)和21d(38日龄)分别用右心导管法及直接导管法测定扎鲁司特对肺动脉压(PAP)和股动脉压(FAP)的影响，同时测定红细胞压积(PCV)和腹水心脏指数(AHI)。结果：(1)在低温环境的早期，扎鲁司特使肉鸡肺动脉收缩压和舒张压均升高，后期仅使舒张压升高；(2)扎鲁司特使PCV升高，增加了血液黏性阻力；(3)扎鲁司特使AHI升高，促进右心肥大；(4)扎鲁司特对股动脉压无显著性影响。可见扎鲁司特促进了肉鸡肺动脉高压综合征的发生发展。     

BQ123对低温诱发的肉鸡肺血管重塑的影响

动态观察了肺小动脉中膜平滑肌的增殖及管腔面积的改变,探讨内皮素受体拮抗剂BQ123 对低温诱发的肉鸡肺血管重塑的影响。200只16日龄AA肉鸡随机均分为4组: 常温(20 ℃)对照组、低温(7~9 ℃)组、低温低剂量BQ123组和低温高剂量BQ123组。23日龄、30日龄时测定肺动脉压,并取肺组织做石蜡切片, 以Weigert间苯二酚复红染色,形态学计算机图象分析法测定肺细小动脉外径和内径、管总面积和管腔面积,计算中膜厚度占外径百分值(%)mMTPA及管壁面积/管总面积WA/TA(%)。结果显示:(1)BQ123 抑制低温肉鸡平均肺动脉压的升高,23日龄时低温高剂量BQ123组显著低于低温组(P<0 05),30 日龄时低温低剂量BQ123 组和低温高剂量BQ123组均极显著低于低温组(P<0 01);(2)BQ123 抑制低温肉鸡肺小动脉WA/TA(%)的升高,30~50μm的肺小动脉,低温组极显著高于低温低剂量BQ123 组及低温高剂量BQ123 组(P<0 01),其它分级的肺小动脉组间差异性与此类似;(3) BQ123抑制低温肉鸡肺小动脉的mMTPA的升高,30~50μm的肺小动脉,23日龄时低温组极显著高于低温低剂量BQ123 组和低温高剂量BQ123 组(P< 0 01), 30 日龄时低温组显著高于低温低剂量BQ123组(P<0 05)、极显著高于低温高剂量BQ123组(P<0 01),30μm以下的肺小动脉组间差异性与此类似,50~120μm     

低温高能日粮对肉鸡肺动脉和腹水症的影响

本试验用高能日粮饲养１日龄ＡＡ父母代公雏，２１日龄开始用低温估为发病模型诱发肉鸡腹水症，取不同日龄的肉鸡肺脏和肺动脉固定，光镜和电镜观察肺脏组织学变化，用图像分析仪进行肺动脉测定，结果如下：低温组３５日龄时直径５０～１００rm、１００～２００um肺动脉中膜肥大，管腔面积，差异极显著（Ｐ〈０．０１）。外膜下弹力纤维、胶原纤维增多。低温下２８日龄超微结构观察表明肺动脉内皮细胞肿胀、细胞突起消失。随着低温时     

低温诱发肉鸡腹水综合征发生过程中肺血管重塑与肺动脉高压的关系

将160只15日龄雄性AA商品代肉鸡随机分为对照组((22±1.5)℃)和低温组((11±2)℃)。15~50日龄,每组每周随机取6只,以右心导管法直接测定肺动脉压(PAP),并取肺组织做石蜡切片进行Weigert-间苯二酚复红染色,分析肺血管重塑情况。50日龄时统计整个饲养过程中肉鸡腹水综合征(AS)发生率。结果显示,低温组肉鸡AS发生率(18.75%)极显著高于对照组(1.25%)(P<0.01);低温组肉鸡PAP从22日龄开始较对照组明显升高(P<0.01或P<0.05);20~50、50~100、100~200μm肺动脉结构分别从36、43、43日龄开始较对照组发生了明显的重塑(P<0.01或P<0.05)。结果表明,低温诱发肉鸡AS过程中出现了明显的PAP升高和肺血管重塑,且肺动脉高压(PH)促进了肺血管重塑,肺血管重塑加剧了PAP升高。     

组胺受体拮抗剂对低致病性禽流感患鸡血液指标的影响

为了研究组胺受体拮抗剂对低致病性禽流感病毒(LPAIV)感染黑脚麻鸡后的患鸡血液学的影响,探讨组胺受体1(H1)、组胺受体2(H2)在低致病性禽流感发生发展过程中的作用,试验选用120只1日龄黑脚麻鸡,育雏至1月龄后每日早晚分别注射0.4 mL/kg的组胺受体拮抗剂或生理盐水,并通过滴鼻感染禽流感病毒H9N2(107EID50),具体分为4组,阴性组(灭菌生理盐水)、阳性组(灭菌生理盐水+H9N2)、扑尔敏(扑尔敏+H9N2)组和西咪替丁(西咪替丁+H9N2)组,分别在第37、44、51日龄采血,测定血液指标。结果显示:扑尔敏组血液中白细胞数量、淋巴细胞数量在37和51日龄时均极显著(P0.01)高于西咪替丁组和阳性组;第44日龄阳性组白细胞数量、淋巴细胞数量极显著(P0.01)高于阴性组和扑尔敏组。37和51日龄时阳性组红细胞数量、血红蛋白浓度、红细胞体积和血小板含量均极显著(P0.01)低于阴性组和扑尔敏组;44日龄时阳性组红细胞数量、红细胞体积和血红蛋白浓度极显著(P0.01)低于阴性组和扑尔敏组,而阳性组和西咪替丁组血小板含量极显著(P0.01)高于阴性组和扑尔敏组。结果表明:扑尔敏能够稳定低致病性禽流感患鸡血液中白细胞数量、淋巴细胞数量、红细胞相关指标和血小板数量,西咪替丁效果不显著。     

环境低温和T3对肉鸡内皮素、一氧化氮和肺动脉压的影响

20 0只 AA肉鸡随机等分为对照组 (C)和试验组 (T) ,C组和 14日龄前 T组鸡按常规饲养。 T组自 14日龄起舍温从 2 5℃起每天降 1～ 2℃逐渐降至 12℃ ,同时在日粮中按 1.5 m g/ kg的剂量添加三碘甲腺原氨酸 (T3 )以诱发肺动脉高压综合征 (PHS)。分别于 2 1、2 8、35、42、49日龄测定 2组肉鸡平均肺动脉压 (m PAP)、红细胞压积 (PCV)、右心全心比 (RV/ TV)、血浆内皮素 (ET- 1)及一氧化氮 (NO)水平 ,同时记录 PHS发病率。结果显示 ,试验组肉鸡 m PAP升高 ,PHS发病率增加 ;PCV、RV/ TV及血浆 ET- 1水平与对照组相比都显著升高 (P<0 .0 1) ;m PAP变化与血浆 ET- 1含量变化之间存在显著正相关 ,2组间血浆 NO水平无显著差异 (P>0 .0 5 ) ,但都出现随日龄增加血浆 NO水平升高的现象。     

红三叶异黄酮对肉鸡肺血管重构和平滑肌细胞凋亡的影响

为观察在低温环境下红三叶异黄酮对肉鸡肺血管重构和平滑肌细胞凋亡的影响,选取270只10日龄肉鸡,随机分为常温对照组(Ⅰ)、低温组(Ⅱ)和低温黄酮组(Ⅲ),每组6个重复,每个重复15只,Ⅰ组和Ⅱ组饲喂基础饲粮,Ⅲ组饲喂添加红三叶异黄酮20mg/kg的试验饲粮,分别于14,21,28,35,42日龄从各组随机抽取6只肉鸡,观察各组肉鸡肺血管病理形态学变化,检测Caspase-3和Bcl-2蛋白表达情况。结果表明,Ⅱ组肉鸡肺小动脉结构在28,35,42日龄比Ⅰ组肺小动脉管壁有不同程度增厚、管腔变窄,发生了明显的重构现象(P0.05或0.01)。Ⅲ组与Ⅱ组相比,在28,35,42日龄肺血管重构现象减轻(P0.05或0.01),肉鸡肺动脉高压综合征(PHS)发病率降低,血管平滑肌细胞Caspase-3蛋白阳性率增高,Bcl-2蛋白表达下降;表明红三叶异黄酮能有效减轻肉鸡肺血管重构,其机制可能与调节平滑肌细胞凋亡有关。     

环境低温对肉鸡肺小动脉壁c-mycmRNA表达的影响

对环境低温诱发肉鸡肺动脉高压综合征(Pulmonary hypertension syndrome,PHS)过程中肺小动脉壁c-mycmRNA的表达变化进行了研究,从而初步确定原癌基因c-myc在环境低温诱发肉鸡PHS过程中的参与作用,为肉鸡PHS发生机制的研究提供基础。120只雄性AA商品代肉鸡15日龄时随机分为对照组((22±1.5)℃)和低温组((11±2)℃)。15～50日龄,每周每组随机取6只,肺组织做石蜡切片,应用原位杂交染色法进行c-myc mRNA杂交,并结合图像分析法,测定环境低温诱发肉鸡PHS过程中肺小动脉壁原癌基因c-myc mRNA的表达情况。结果显示,低温组肉鸡PHS发生率(15.00%)极显著高于对照组(1.67%)(P<0.01);低温组肉鸡肺小动脉壁c-mycmRNA的表达从22日龄开始较对照组明显增加(P<0.05),从29～50日龄较对照组极显著升高(P<0.01)。结果表明,环境低温明显诱发了肉鸡肺小动脉壁c-myc mRNA的表达,且c-myc mRNA的表达参与了环境低温诱发的肉鸡PHS的发生发展。     

肺动脉高压与肉鸡腹水综合征发生发展的关系

２００只艾维茵商品代肉鸡常规育雏,１５日龄时随机分为两组,１００只在常规温度（２７～２３）℃下饲养,为常温组;１００只在低温（９～１１）℃环境中饲养,为低温组。利用右心导管法动态测定肺动脉压（ＰＡＰｍ）,并测定腹水心脏指数（ＡＨＩ）,统计各组腹水发生率。结果为：（１）分组后７、２１ｄ,低温组ＰＡＰｍ极显著高于常温组（Ｐ〈０．０１）;低温组腹水发生率显著高于常温组（Ｐ〈０．０５）。表明低温可引起肺动     

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.