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1.
为了探索高氟低蛋白对牙齿发育的影响 ,阐明牙齿过度磨损的机理 ,应用扫描电镜对第一、二切齿脱钙前的矿化及脱钙后的基质结构作了观察。结果表明 ,脱钙前对照组牙本质小管纵向排列整齐 ,走向一致 ;中毒组第一切齿牙本质小管纵向排列不齐 ,走向紊乱。脱钙后 ,对照组牙齿胶元纤维排列整齐致密 ,而中毒组胶元纤维排列较疏松 ;对照组横断面牙本质小管分布均匀 ,管径大小一致 ,管型规则 ,管壁与管间质密度一致 ;而中毒组小管口径不一 ,管型不规则。结论 :高氟低蛋白营养首先影响牙基质的发育 ,进一步影响矿化 ,从而使牙齿整体发育不良 ,过度磨损。  相似文献   

2.
为研究不同剂量的环磷酰胺对小鼠肝肾组织及功能的损害程度,试验选取40只5周龄健康雌性昆明小鼠,随机分为5组,除对照组外,其余4组小鼠连续3 d分别腹腔注射40、80、120及160 mg/（kg·BW）环磷酰胺溶液,注射后第7天采集肝脏和肾脏组织样品及血清,制备石蜡组织切片及透射电镜切片,观察肝脏和肾脏的组织学变化,检测血清中甘胆酸（CG）、胆碱酯酶（ChE）、血清前白蛋白（PA）、总胆汁酸（TBA）、谷丙转氨酶（ALT）、谷草转氨酶（AST）、尿素氮（BUN）、血清肌酐（SCr）、尿酸（UA）含量/活性。结果显示,环磷酰胺可引起小鼠肝肾组织病理损害,呈剂量依赖性,肝脏比肾脏更早出现损伤。石蜡切片及透射电镜切片观察结果显示,环磷酰胺对肝脏的毒性作用主要表现在肝索紊乱、肝血窦扩张、微胆管淤胆、门管区及中央静脉周围炎性细胞浸润及纤维增生、组织间出血、肝细胞出现脂肪变性及气球样变性,凋亡及坏死细胞增多。肾脏组织损伤主要表现在出血及纤维增生,肾小管上皮细胞胞浆空泡样变、线粒体损伤、核固缩,上皮细胞基底膜增厚。环磷酰胺对膀胱的损害不严重。与对照组相比,40~160 mg/（kg·BW）剂量组小鼠血清中ChE活性及PA水平,120~160 mg/（kg·BW）剂量组AST活性,80~160 mg/（kg·BW）剂量组BUN水平及80 mg/（kg·BW）剂量组UA水平均显著升高（P<0.05）;其余生化指标与对照组差异不显著（P>0.05）。以上结果表明,环磷酰胺注射剂量在80~120 mg/（kg·BW）时可引起昆明小鼠肝脏和肾脏组织及细胞明显的病理损伤。该研究结果可为选择合适的环磷酰胺注射剂量用以制备动物肝脏免疫抑制模型提供试验依据。  相似文献   

3.
前言天津市工农联盟农牧场位于天津市郊,地势低洼,该场饲养的奶牛自1967年来陆续发生以四肢及全身骨骼变形为主的“肢蹄病”。病牛跛行,骨骼变形及因此而引起的姿势改变,牙齿松动排列不整,并有褐色齿斑。该场所在地属盐硷土地(pH 8.2—8.4),水和饲料含氟量偏高(水含氟量为2.8—3.2毫克/升),尿中含氟量也较高,经检查确认,该场的“肢蹄病”中为慢性氟中毒病。本研究除注意到文献记载的慢性氟中毒时骨骼、牙齿的特  相似文献   

4.
王量  范红结 《中国畜牧兽医》2017,44(7):2160-2164
为研究不同剂量氟化钠对獭兔的影响,试验建立獭兔氟中毒模型并对獭兔血液、骨骼、肝脏、肾脏等器官氟含量进行测定。试验獭兔日龄（30±5） d,体重（1.1±0.2） kg,数量24只,分为3组：对照组、试验Ⅰ组（10 mg/（kg·d）氟化钠组）和试验Ⅱ组（20 mg/（kg·d）氟化钠组）,试验共100 d。结果表明,试验第100天测定的骨骼和牙齿氟含量在各组之间均差异显著（P<0.05）,且骨骼和牙齿的含氟量随时间和摄入氟剂量的增加而递增;肾脏和肝脏氟含量在各组之间均差异不显著（P>0.05）;试验Ⅰ、Ⅱ组间血液氟含量差异不显著（P>0.05）,但都与对照组差异显著（P<0.05）。氟化钠作为氟化物来源可用来建立獭兔自然状态氟中毒症,骨骼和牙齿累积氟能力强,血液、肝脏和肾脏累积氟能力弱。本试验为进一步研究獭兔氟中毒及其防制提供了理论参考。  相似文献   

5.
经蓝舌病病毒云南株攻击绵羊的颊部超微病理学观察   总被引：1，自引：0，他引：1  
用蓝舌病病毒云南株强毒攻击绵羊，对其颊部进行了超微病理学研究。结果表明，颊粘膜棘细胞层严重损伤，表现为棘细胞核浓缩，崩解，线粒体肿胀变圆，乃至破裂，粗面内质网扩张，脱颗粒，间桥断裂，形成大量空泡；固有层血管内皮细胞翘起，脱离基膜，内皮细胞内也可见大量空泡；在攻毒后期，固有层有嗜中性粒细胞，巨噬细胞和淋巴细胞浸润，成纤维细胞增生，胶原原纤维增多且排列紊乱。上述病理学变化说明，蓝舌病病毒云南株主要危害  相似文献   

6.
本文选择体重0.7～1.2kg,20～30日龄健康的新西兰白兔24只,随机分为实验和对照两组,对照组饮自来水(含氟量0.25ppm),实验组饮按每公斤体重45mg氟化钠(化学纯)配制的水溶液。实验组每隔30天剖杀一次、进行尿样、血样及毛、爪、骨、肝、肾等氟含量的测定。实验结果证明,临床上实验30天即出现中毒症状,60～90天后发育迟缓,体重明显下降;投氟30天后,实验组家兔骨氟、血氟、爪氟、毛氟、尿氟、尿HYP含量明显高于未投氟的对照组(p<0.01);因此,羟脯氨酸(HYP)的测定是监测和诊断慢性氟中毒的早期辅助指标;尿氟和血氟的测定可作为诊断慢性氟中毒参考指标;爪氟含量与骨氟含量呈正相关,爪氟含量测定可以监测和诊断中毒程度,是目前早期诊断氟中毒的一种比较理想可靠的方法。  相似文献   

7.
本试验旨在了解小瓜虫(Ichthyophthirius multifiliis)感染草鱼后对草鱼肝脏、肾脏和肌肉等组织器官线粒体的影响.人工方法用小瓜虫感染健康草鱼,确定草鱼成功感染小瓜虫后,透射电镜观察肝脏、肾脏和肌肉组织中线粒体结构的变化,检测这些组织器官的过氧化物歧化酶(SOD)和丙二醛(MDA)含量.透射电镜观察结果显示,与正常组相比,感染组肾脏、肝脏和肌肉组织线粒体数量减少,线粒体肿胀、嵴断裂或消失.感染组肝脏、肾脏和肌肉组织中SOD含量平均值均高于正常组,其中肝脏、肾脏表现为差异显著(P <0.05),肌肉组织差异不显著(P >0.05);感染组肝脏、肾脏和肌肉组织中MDA平均含量均低于正常组,其中肝脏、肾脏表现为差异显著(P <0.05),肌肉组织差异不显著(P >0.05).结果表明,小瓜虫感染草鱼后,对草鱼的肝脏、肾脏和肌肉组织的线粒体结构及SOD和MDA活性均有影响.  相似文献   

8.
用透射电镜和羟脯氨酸检测试剂盒,分别观察了产后1个月内小尾寒羊子宫胶原纤维的排列状况,以及血和尿中羟脯氨酸(HYPRO)含量的变化情况。结果表明:产后初期子宫组织内胶原微纤维排列不规则,到产后第25天时,胶原结构从形态上恢复到了正常状态;小尾寒羊产前40d血和尿中HYPRO的浓度高于产前7d,在产后1～7d其含量迅速升高并达最大值,从产后7～31d其含量缓慢降低;在产后31d的含量介于产前40d和产前7d对照组之间。小尾寒羊尿中HYPRO的浓度是血中浓度的近20倍。本实验结果证明,胶原蛋白的降解与子宫复旧密切相关。  相似文献   

9.
雏鸭实验性镉中毒的病理学研究   总被引：5，自引：0，他引：5  
用114只3日龄肉鸭作急性、亚急性镉中毒的病理学观察。急性镉中毒的LD50为289mg/kg体重。灌服1／10、1／20、1／30LD50剂量作亚急性毒性试验，每日服药一次，试验期6周，其发病率分别为11／11、11／11和3／11，死亡率分别为10／11、7／11和3／11。中毒鸭表现为生长缓慢，Hb、RBC和PCV显著降低，死前多呈现呼吸困难。尸体剖检和病理组织学变化主要是纤维素性心外膜炎、心肌变性、间质性心肌炎，纤维素性肝周围炎、肝细胞严重脂变、间质性肝炎，纤维素性肺浆膜炎、支气管肺炎，气囊积液、气囊壁水肿和钙化，卡他性肠炎以及脑充血、出血等。透射电镜观察，心肌纤维、肝细胞和肾曲管上皮细胞内线粒体严重肿胀，嵴断裂、溶解。肝细胞还可见糖元颗粒明显减少，脂滴增多等。测得亚急性组织肝脏和肾脏的镉含量，试验组与对照组之间有极显著差异（P＜0．01）。试验组口服镉含量高的与镉含量低的之间亦有显著或极显著差异（P＜0．05或P＜0．01）。  相似文献   

10.
用蓝舌病病毒云南株强毒攻击绵羊,对其颊部进行了超微病理学研究。结果表明,颊粘膜棘细胞层严重损伤,表现为棘细胞核浓缩,崩解,线粒体肿胀变圆,乃至破裂,粗面内质网扩张,脱颗粒,间桥断裂,形成大量空泡;固有层血管内皮细胞翘起,脱离基膜,内皮细胞内也可见大量空泡;在攻毒后期,固有层有嗜中性粒细胞,巨噬细胞和淋巴细胞浸润,成纤维细胞增生,胶原原纤维增多且排列紊乱。上述病理学变化说明,蓝舌病病毒云南株主要危害绵羊颊棘细胞层和固有层血管内皮细胞,造成其损伤,从而揭示出蓝舌病病毒可能是在绵羊颊棘细胞和固有层血管内皮细胞内增殖的,颇棘细胞和血管内皮细胞都是蓝舌病病毒的靶细胞。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
Tropical Animal Health and Production -  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

19.
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.  相似文献   

20.
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  相似文献   

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