驯鹿消化道的组织学观察

本实验采用常规H.E染色法对驯鹿消化道的组织结构进行观察，结果发现驯鹿消化道的组织结构与牛的基本相似。但驯鹿有以下特点：食管的粘膜下层未见有食管腺分布，食管肌层的横纹肌横纹非常明显，前胃的粘膜肌较牛的发达，小肠绒毛较牛的细长；十二指肠的粘膜下层未见有十十指肠腺，小肠腺主要由柱状细胞构成，还有少量的杯状细胞，无潘氏细胞。     

野生黄鼬消化管组织结构的观察

通过组织学观察,探讨野生黄鼬消化管的组织结构特点.将8只野生黄鼬经乙醚麻醉后处死,解剖取食管、胃、小肠、大肠,制作石蜡切片,观察其组织结构.结果显示野生黄鼬食管的黏膜为复层扁平上皮,食管腺发达,肌层以骨骼肌为主.胃贲门部有发达的皱襞和贲门腺;胃底腺有大量的主细胞和壁细胞;胃大弯部的腺体以壁细胞为主,仅有少量主细胞;胃幽门部有发达的幽门腺和大量壁细胞.十二指肠黏膜层有小肠腺,内有潘氏细胞存在,黏膜下层含有十二指肠腺;空肠可见孤立淋巴小结、弥散淋巴组织及集合淋巴小结.结肠无皱襞和肠绒毛,大肠腺排列紧密,其中杯状细胞特别多;直肠固有膜内有发达的大肠腺.所以野生黄鼬消化管的特点是胃各部胃腺发达,壁细胞特别多.     

海狸鼠消化管显微及亚显微结构

应用光镜、电镜和组织化学技术,对 １０ 只成年海狸鼠消化管的食管、胃底、小肠和大肠壁的显微和亚显微结构进行了研究。结果显示,在 Ｈ Ｅ 染色,海狸鼠食管粘膜上皮细胞角化程度较高,胃底腺壁细胞的数量几乎与主细胞的相等或稍多,小肠肠腺底部含有大量潘氏细胞; Ｓｃｈｉｆｆ 氏染色,胃粘膜的上皮细胞、胃底腺的颈粘液细胞、十二指肠腺的粘液细胞、肠腺的潘氏细胞和杯状细胞均为阳性; Ｍ ａｓｓｏｎｆｏｎｔａｎａ 氨银法染色,在胃底腺和肠腺内均见有银亲合细胞。扫描电镜下,胃粘膜表面见有较多胃小凹,小肠上皮细胞的微绒毛形成许多指状突起。透射电镜观察,胃底部壁细胞中线粒体、滑面内质网、细胞内小管发达,小肠上皮细胞的微绒毛密集排列,细胞间见有连接复合体结构,胃底腺和肠腺内见有散在分布的内分泌细胞。     

东北虎胃与小肠组织形态结构的研究

应用光学显微镜对东北虎主要消化管 (胃与小肠 )的显微结构进行了较为详细的观察。结果表明 ,东北虎胃的黏膜中均有胃腺分布 ,没有无腺区。胃的主要部位胃底腺区的胃底腺主要由主细胞和壁细胞组成 ,主细胞较多 ,通常呈小簇存在 ,主要分布在管状腺边缘 ,且越靠近黏膜肌 ,主细胞越多 ,而壁细胞越少。小肠中的十二指肠段 ,黏膜下腺呈棉花团样结构 ,由黏液性高柱状细胞构成 ,肌层呈规则的波浪型 ,内环肌较厚 ;空肠皱襞不明显 ,肠腺单管状 ,苏木素染色深 ,肌层呈规则的“W”型 ,靠近回肠处的空肠段 ,外纵行肌排列较紧密 ,且厚度逐渐增加     

马冈鹅肠胚后发育的组织学观察

将72只5~110d马冈鹅(各半)按不同日龄随机分为9组,先后取十二指肠、空肠、回肠和直肠,应用常规组织学技术和Tiger细胞图像分析系统进行观测。结果表明:各部肠管管壁分粘膜、肌层和浆膜三层,无粘膜下层;绒毛既有分支,也有融合现象;肠腺主要是单管状腺,但也有分支管状腺;粘膜上皮中柱状细胞从前向后逐渐减少,而杯状细胞则相应逐渐增多;肠腺中的柱状细胞则由前向后逐渐增多,杯状细胞相应减少;肌层分内纵、中环、外纵三层,内、外两肌层厚度近似,中环肌最厚,内有明显的结缔组织间隔带分布,小肠段呈有规律的"竹节"状;粘膜皱襞不发达,少数皱襞由粘膜、内纵和中环肌层共同构成;肠壁内淋巴组织丰富,在肌层之间及肌层内均可见淋巴小结,肌层内也有神经丛和神经纤维束的断面;绒毛高度发育的绝对生长高峰期在26d以前,但绒毛直径的发育无明显的阶段性。     

雌性空怀双峰驼生殖道的形态结构

应用组织学方法观察了雌性空怀双峰驼生殖道的形态结构。结果显示，双峰驼生殖道的基本结构与其他哺乳动物相似，但微细结构有差异。双峰驼输卵管粘膜皱襞极其发达，分支多而呈复杂的网状迷路。皱襞基部的迷路酷似固有膜而存在腺体，迷路网格内常见细胞团块。虽然双峰驼怀孕时胎儿位于左侧子宫角，但左、右子宫角以及子宫体的组织结构基本相同。子宫内膜无肉阜，上皮下陷于固有膜内，形成大量长而弯曲的单管状腺。子宫颈固有膜浅层分布有许多小腺体，深层分布有成群的较大腺体。这些腺体为分支管状腺，腺上皮PAS强阳性。阴道粘膜上皮为复层上皮。从输卵管到阴道，粘膜上皮主要为单层柱状上皮，由纤毛细胞和分泌细胞组成，局部可见假复层柱状纤毛上皮。纤毛细胞由前向后逐渐减少，但在子宫颈仍可见到。粘膜上皮和腺上皮内夹有许多淋巴细胞或中性粒细胞，后段局部甚至见到这些免疫细胞浸润于上皮细胞间。固有膜内分布有大量淋巴细胞、中性粒细胞、肥大细胞、浆细胞和巨噬细胞，有时出现淋巴滤泡。     

年龄差异对家兔CD4+T细胞在胃肠分布的影响

为深入了解家兔消化道中CD4⁺T细胞的组织学定位以及在消化道不同解剖学部位的数量变化,本试验运用免疫组织化学方法,探讨了家兔胃(胃底腺区、幽门腺区)和小肠及大肠不同解剖学部位中的CD4⁺T细胞定位特点和数量变化规律。结果表明,在胃肠中,CD4⁺T细胞主要分布于固有层。胃底腺区阳性细胞数目要明显比幽门腺区少。小肠、大肠各段的阳性细胞分布数量未见明显差异,由十二指肠到回肠表现为小幅度递增,由盲肠到直肠表现为小幅度递减。胃肠中CD4⁺T细胞在各部位的数量随年龄增长表现出先增后减的变化趋势,老年组和幼年组CD4⁺T细胞数量在大肠中未见明显差异。结果提示,CD4⁺T细胞在青年家兔胃肠中的分布最为丰富。     

生长籽鹅消化管组织结构的研究

运用常规HE染色方法研究黑龙江籽鹅消化道的组织结构随日龄变化(1日龄、10日龄、30日龄、60日龄、90日龄、120日龄)而变化的规律。结果表明,随籽鹅日龄的增长,消化道管壁变厚,腺胃浅层分布的管状腺增加,肌胃固有层的沙囊腺的数量增多,小肠和大肠绒毛内杯状细胞的数量也逐渐增多。     

青海沙蜥消化道嗜银细胞的分布及形态观察

为了探索爬行动物消化道内分泌细胞的分布规律和形态类型,本文应用Grimelius嗜银染法对青海沙蜥消化道嗜银细胞进行了研究。结果显示,嗜银细胞主要分布于胃肠道,多数分布于粘膜上皮和腺泡上皮之间;其中在胃幽门处分布较多,小肠处较少。形态有梭形、锥体形、椭圆形、圆形、多角形和不规则形等。     

双峰驼胃底腺区黏膜组织学与组织化学研究

用组织学和组织化学研究方法重点观察了双峰驼胃底腺的细胞组成、分布及其组织化学特性。结果表明，双峰驼胃底腺区有发达的黏膜皱襞和厚的黏膜层，固有层中充满长而直的分支管状腺，由颈黏液细胞、壁细胞、主细胞和亲银细胞组成。颈黏液细胞分布在腺颈部，为混合黏液细胞，以分泌酸性糖共轭物为主。壁细胞十分丰富，分布于整个腺体，以腺体体部最多，细胞内含有酸性磷酸酶和碱性磷酸酶以及活性较强的非特异性醋酶，糖共轭物呈色均为阴性。主细胞位于腺体体部和底部，胞质中有大量的嗜碱性颗粒，含非特异性醋酶，但无糖共轭物。在黏膜褶顶部腺体体部和底部常看到不成熟的主细胞，其形态同颈黏液细胞和主细胞相似，为矮柱状或立方状，胞质有大量细小的颗粒，糖共轭物呈色反应和颈黏液细胞相似。糖共轭物呈色结果还显示，胃底腺区黏膜表面上皮仅分泌中性糖共轭物，胃小凹上皮和颊部腺上皮可分泌混合糖共轭物，胃小凹浅层上皮以中性糖共轭物为主，而底部上皮和颊部腺上皮以酸性糖共轭物为主。此外，在网状纤维染色时我们发现颈黏液细胞有明显的嗜银现象，核上胞质可见大量的嗜银颗粒，不成熟的主细胞有类似表现，但较其弱，颊部腺上皮也有较弱的嗜银性，而成熟的主细胞则无此特点，建议将此法作为颈黏液细胞和主细胞的鉴别方法。虽然双峰驼胃底腺区黏膜的微观结构及组织化学特性同其他动物和人有差异。但基本结构相似。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein