牦牛和柴达木黄牛的颈动脉体Ⅰ型细胞线粒体和电子致密核心囊泡的体视学比较

作者旨在比较牦牛和柴达木黄牛颈动脉体(CB)Ⅰ型细胞线粒体和电子致密核心囊泡(EDCV)的体视学特征。选择海拔3 200m地区健康成年牦牛和柴达木黄牛各5头,采用透射电镜技术观察CB的超微结构,并运用立体定量方法比较牦牛和柴达木黄牛颈动脉体Ⅰ型细胞线粒体和EDCV的体密度(Vν)、面密度(Sν)、面数密度(NA)、比表面(δ)。结果表明,牦牛和柴达木黄牛的颈动脉体实质细胞主要由Ⅰ型细胞和Ⅱ型细胞组成,颈动脉体Ⅰ型细胞细胞质中含有大量的线粒体和特征性的电子致密核心囊泡。牦牛Ⅰ型细胞线粒体的Vν值大于柴达木黄牛,但差异不显著(P0.05);牦牛S_v、N_A、δ值均小于柴达木黄牛,其中Sν、δ值在两组间差异均不显著(P0.05),NA在两组间差异显著(P0.05);牦牛Ⅰ型细胞质内EDCV的Vν值小于柴达木黄牛(P0.05);牦牛Sν、NA和δ值均大于柴达木黄牛(P0.05)。结果提示这种结构特征可能使牦牛对环境低氧的感知比生活在相同海拔高度的柴达木黄牛迟钝。     

不同海拔牦牛颈动脉体Ⅰ型细胞线粒体和EDCV的体视学

颈动脉体(carotid body,CB)是第一个被发现的缺氧感知器官,当血液PaO2降低时,迅速引起呼吸加深、加快等反应。为探讨牦牛不同低氧程度下CB的适应特征,应用透射电子显微镜技术和体视学方法测量了海拔4 600,3 800和2 800m牦牛颈动脉体Ⅰ型细胞线粒体、电子致密核心囊泡体(electron dense-cored vesicles,EDCV)的体密度(Vv,单位体积Ⅰ型细胞浆中线粒体、EDCV的体积百分比)、面密度(Sv,单位体积Ⅰ型细胞浆中线粒体、EDCV外膜的表面积)、面数密度(NA,单位面积中线粒体、EDCV数目)、比表面(δ,线粒体、EDCV表面积与其自身体积之比)。结果表明,牦牛颈动脉体Ⅰ型细胞浆内线粒体的Vv值随着海拔的升高呈增加趋势,但3组间差异不显著(P0.05);Sv、NA、δ值随着海拔从2 800m升到3 800m先减小,从3 800m到4 600m而增加,3组间差异均不显著(P0.05)。牦牛颈动脉体Ⅰ型细胞浆内EDCV的Vv、Sv值随海拔升高呈上升趋势,但3组间差异均不显著(P0.05);δ值随海拔升高呈下降趋势,3组间差异也不显著(P0.05)。     

不同海拔条件下牦牛颈动脉体组织微细结构的比较研究

旨在揭示牦牛在不同程度低氧下颈动脉体的结构特征。本研究采用组织学、免疫组织化学方法和透射电子显微镜技术,对青海省不同海拔的成年健康牦牛颈动脉体的形态结构进行观察,并运用显微体视学方法比较Ⅰ型细胞(明细胞、暗细胞)、Ⅱ型细胞和血管的体密度(Vv)、面密度(Sv)、面数密度(NA)、比表面(δ)。结果表明,牦牛颈动脉体中明细胞数量多、暗细胞较少,胞质含大量线粒体和特有的电子致密核心囊泡,随着海拔升高,线粒体和EDCV的大小和数量无明显变化;Ⅱ型细胞分布于Ⅰ型细胞的周围,细胞小而少。间质中分布有丰富的毛细血管,管腔随海拔升高逐渐变大。明细胞的Sv、NA随着海拔的升高逐渐增大,各海拔组之间差异显著;暗细胞的Vv、Sv和NA随着海拔的升高逐渐增大,海拔4 600m与2 800m组间差异均显著;Ⅱ型细胞的Sv、NA随着海拔的升高逐渐增大,海拔4 600m组与其它两组间(海拔2 800m组和3 800m组)差异均显著;颈动脉体微血管的Sv、δ随着海拔的升高逐渐减小,且Sv在海拔4 600m与2 800m组之间差异显著,δ各组之间差异均显著。综上表明,随着海拔升高,牦牛颈动脉体Ⅰ型细胞和Ⅱ型细胞数量明显增多、微血管明显扩张。     

哺乳动物胎肺发育的形态学研究

哺乳动物胎肺的发育可以分5个时期：胚胎期、假腺期、小管期、囊状期和肺泡期。人、绵羊和山羊胎儿至出生时肺的发育已基本完善，处于肺泡期；而兔、大鼠和小鼠的胎儿至出生时肺的发育尚处于囊状期。甩泡表面上皮细胞的分化和气血屏障的形成是肺发育的形态学标志。呼吸功能的建立，与Ⅱ型上皮细胞的分化密切相关。Ⅱ型细胞的分化标志有以下几点：①糖原的变化；②粗面内质网池扩张，并出现絮状物质；③多泡体出现及高尔基小泡增多；④胞质内微管出现；⑤腔面生成微绒毛；⑥致密小体内板层的出现等。     

生物囊泡分离鉴定方法及其在兽医学中的应用

生物囊泡是细胞产生的一种膜性小泡,内含丰富的DNA、蛋白质、脂质等生物活性物质,是细胞间重要的信息传递媒介。近年来,生物囊泡在兽医学领域的研究主要集中于外泌体或微囊泡,为抗寄生虫药物研究和某些动物疾病诊断提供了新思路。然而,生物囊泡的分离、纯化及鉴定技术仍是该领域的技术瓶颈,制约了生物囊泡进一步的应用及研究。文章归纳整理国内外相关文献,综述了生物囊泡的类型、分离纯化方法、鉴定技术及其在兽医学中的应用等,以期为生物囊泡应用于兽医临床诊疗提供参考。     

犬新孢子虫和刚地弓形虫超微结构的比较

使用透射电镜，对从犬获得的三株犬新孢子虫分离株的感染培养细胞的速殖子超微结构进行检查。三个分离株的超微结构相似，速殖子具有一个表膜、２２个表膜下微管、一个类椎体，前后均有极环，８—１２个电子致密对式细胞器、大量微丝、一个单在泡状核、管状线粒体、高尔基复合体、核糖体、内质网、一个无活性的微孔、电子致密体、脂质体和技链淀粉体。大多数速殖子寄生在靠近宿主细胞核寄生性空泡中，它含有大量内空泡管。速殖子以内出芽形式分裂。没有观察到犬新孢子虫组织包囊。犬新孢子虫和刚地弓形虫的速殖子可根据对式细胞器的结构和数量、微丝和电子致密体的数量和位置予以区别。     

鸭病毒性肠炎病毒强毒在人工感染鸭体内形态结构和发生学的电镜观察

为研究鸭病毒性肠炎病毒(DEV)CH强毒株在感染鸭体内的分布和形态学发生规律，应用透射电镜和超薄切片技术对人工感染DEV的成年鸭各组织器官进行观察。结果表明：感染后12h在脾脏和法氏囊首先观察到少量的DEV出现，24h后在脾、胸腺和法氏囊以及死亡鸭的肝、肠和胰中均观察到具有典型的疱疹病毒粒子及其核衣壳形态的DEV。DEV病毒核衣壳有空心型、致密核心型、双环型和内壁附有颗粒型4种形态，存在胞核和胞浆两种装配方式。病毒成熟有两种方式：一为细胞核内核衣壳在核内获得皮层，通过核内膜获得囊膜成为成熟病毒；二为核内核衣壳通过内外核膜进入胞浆，核内和胞浆内的核衣壳在细胞浆中获得皮层，然后在各种质膜上获得囊膜，最后成熟病毒通过细胞破裂或其他方式释放到细胞外。伴随着病毒的复制、装配和成熟，细胞中出现多种核内和胞浆包涵体、核内致密颗粒、核内微管和中空短管、胞浆电子致密小体等结构。     

蛋鸡常用抗热应激的添加剂

热应激(Heat Stress)是指在高环境温度中的机体对热环境中机体提出的任何要求所做出的非特异性的生理反应的总和。非特异性生理反应,如热喘息,呼吸运动加快,二氧化碳排除增加,呼吸性碱中毒;心率加快,心力衰竭,脑充血,肺水肿,缺氧等;体     

肉鸡腹水症病因调查与结论

肉鸡腹水症以腹腔积液、死亡为特征。通风不良、呼吸性疾病、生长过速(需氧量增多)和高海拔(低氧)条件下饲养等因素可促进本病的发生。1 肉鸡腹水症的发病机理应激超过了鸡肺或心的正常生理功能,不能将足够的氧运送给组织,从而致组织缺氧;为了弥补组织缺氧,机体心跳加快,以增加肺和其他组织脏器的血流量;此时心脏开始增大,当心脏增大到一定程度后,血液倒流到心脏,此时右心衰竭;血液流至全身,由于小血管内血压过高,促使血液成分渗入腹腔和心包腔等,从而形成临诊上所见到的腹腔和心包腔大量积液的病变,进而导致突然死     

外泌体对动物肠道健康的影响及其研究方法

在无抗养殖的大背景下,动物的肠道健康问题愈加引起关注。肠道是机体消化吸收营养物质的主要器官,也是防止肠道微生物侵袭的先天屏障,肠道屏障功能的完整性对机体的正常生长发育起着至关重要的作用。外泌体是一种内源性调节物质,可作为解决肠道健康问题的切入点。外泌体是由多种类型细胞分泌的纳米级细胞外囊泡,其广泛分布于各种体液中,可携带蛋白质、核酸、脂质等生物活性物质,它们参与细胞之间的传递、细胞的迁移和增殖等进程,在机体的生理和病理过程中发挥作用。近期研究表明,外泌体可通过调节肠道菌群的组成、诱导小肠干细胞的增殖,修复动物的肠道屏障功能。作者梳理了近年来外泌体对畜禽肠道健康影响及外泌体的研究方法,为后续相关研究提供参考。     

硼对鸡10项生理生化指标的影响

300羽1日龄固始鸡随机分为4组,探讨在饮水中补充硼对鸡10项生理生化指标的影响,为研究硼的生物学作用提供科学依据.结果表明,补硼鸡体温、心跳和呼吸次数无明显变化;全血硼含量增加;红、白细胞数、血红蛋白含量和血清钙、磷、镁随着补硼量的增加而降低.     

Calcium-Binding Proteins and Neurotransmitters in the Stomach Myenteric Plexus of the Korean Native Goat

The expression of calbindin D-28k (CB), calretinin (CR), substance P (SP) and calcitonin gene-related peptide (CGRP) in the stomach myenteric plexus of the Korean native goat stomach was investigated by immunohistochemistry. The results demonstrated the presence of nerve fibers and cell bodies immunoreactive (IR) to CB, CR, SP and CGRP. In tissues of rumen, reticulum, omasum and abomasum, some distinct neuronal populations could be distinguished according to their morphologic and neuronal chemical properties: Dogiel type I cells which have irregular lamellar dendrites and a single axon, Dogiel type II cells which have large ovoid cell bodies and several long axon-like processes, and small filamentous interneurons. CB-, CR-, SP- and CGRP-IR neurons and fibers were observed in the myenteric plexus of stomach, and varicose nerve fiber immunostained to SP and CGRP also were found in the muscle layer. In myenteric plexus of the stomach, CB- and SP-positive neurons were characterized by Dogiel type II and CR-IR neurons were classified Dogiel type I with lamellar dendrites, and immunoreactivity of CGRP was very weak in the somata. SP- and CGRP-IR nerve fibers formed dense networks within the myenteric ganglia. SP-IR cell bodies and their fibers were found in the myenteric plexus, and the immunoreactivity and number of cell bodies were more than CB-, CR-, and CGRP-IR neurons. These results suggest that SP, CGRP, CB and CR in the myenteric neurons of Korean native goat stomach may have play an important role in the dynamic movement.
(Support contributed by: Korean Research Foundation 2003-015-E00195).     

Physiological reactions of suckler calves from a cow-calf operation exposed to transport stress and temporary separation from the herd in winter stalling

Suckler calves from a cow-calf operation (German Red Pied, German Black Pied) were used repeatedly for separation, transport and isolation (TSI) experiments of 60 min duration at five life ages. Measurements of body weight, body temperature and heart rate were combined with blood sampling before TSI, and at the end of the isolation period of one hour duration as well. Effects of gender, age and body weight on the variables and on the changes of the variables were tested. Characteristic heart rate values showed the increasing excitement and the motor activation of the animals in case of transport and of manipulations and the periods of relative rest within the isolation room as well. Mean noradrenalin concentration was significantly lower after TSI at all age points, mean adrenalin concentration was significantly higher after TSI at 9-14 days and significantly lower at 59-77 days of age than before. Changes of adrenalin concentration were significantly influenced by body weight and age. Sex, body weight and age had significant effects on hemoglobin (Hb), hematokrit (Hk), mean corpuscular hemoglobin concentration (MCHC), oxygen capacity (O2CAP) and oxygen contents (O2CONT). Hb, Hk and O2CAP were significantly diminished after TSI at all age points, O2CONT and oxygen saturation (O2SAT) were significantly increased after TSI at many age points. Shrinking of body weight after TSI was always significant and was significantly affected by body weight before TSI and by age. Body weight and age had significant effects on body temperature and its changes after TSI.     

Immobilization of Japanese black bears (Ursus thibetanus japonicus) with tiletamine hydrochloride and zolazepam hydrochloride

The effect of anesthetizing with a 1:1 combination of tiletamine hydrochloride and zolazepam hydrochloride (TZ) was evaluated in 75 Japanese black bears. TZ was administered to 43 captive and 11 wild, 8 captives and 13 hibernating captive bears at the doses of approximately 9.0 mg/kg (usual dosage), 18.0 mg/kg (high dosage) and 5.0 mg/kg (low dosage), respectively. Sufficient anesthetic effects were achieved in all bears, and rectal temperatures, heart rates and respiratory rates did not change significantly during an hour handling. Complete blood cell examinations showed no abnormal data. A combination of TZ would be an efficient and safe drug for chemical immobilization of Japanese black bears.     

Determination of carbendazim residues in the eggs, liver and pectoral muscle of Japanese quail (Coturnix coturnix japonica)

The effect of carbendazim, a widely applied cereal seed dressing agent, was studied in Japanese quail (Coturnix coturnix japonica) during an overall period of eight weeks, consisting of a four-week feeding phase and a subsequent four-week excretion period. Body mass and feed consumption of the birds were monitored and residues of the active ingredient were determined by an analytical chemical method. During the eight-week study period, changes (either decrease or increase) directly attributable to the toxic effects of carbendazim were not found either in body mass or in feed consumption. Active ingredient levels exceeding the limit of detection were found in the liver (average: 0.0262 mg/kg) and pectoral muscle (average: 0.0236 mg/kg) of the birds and also in the egg (0.0338 mg/kg) samples. From the results it can be concluded that through the consumption of cereal seeds dressed with carbendazim, this active ingredient can be incorporated into the tissues of animals. Via the food chain, carbendazim can also enter the human organism, where it may cause various pathological changes in interaction with other chemicals.     

Physiological effects of etorphine, acepromazine and xylazine on the black fallow deer (Dama dama)

Confined and unconfined fallow deer (Dama dama) of the black variety kept at Whipsnade Park were sedated with etorphine in combination with acepromazine, or xylazine or both, with or without atropine. Induction, sedation and recovery times were recorded. During the period under sedation, systemic and pulmonary arterial pressures, electrocardiographs, body temperature, arterial blood gas pressures and pH, packed cell volume and plasma electrolytes and enzymes were monitored. In both groups, and with all drug combinations, heart rates (except where atropine was used and respiratory rates were depressed, pulmonary arterial pressures were elevated, and blood oxygen tension and pH lowered compared with interspecies norms. In confined animals, systemic arterial pressures were depressed. Unconfined animals and animals in which atropine was used showed higher and more varied systemic arterial pressures and more varied heart rates. Cardiac arrests occurred in eight animals, five during induction and three during sedation, one of which was revived with oxygen. Severe arrhythmia occurred in an animal in which atrioventricular block was confirmed and reversed by oxygen treatment.     

动物肠道铁吸收、转运及其调节的分子机制

铁是动物必需的微量矿物元素,在机体内发挥氧气运输、电子传递、细胞增殖等重要的生物学功能。缺铁或铁过量均会对机体产生危害。肠道铁吸收是调节机体铁稳态的重要环节,目前已经清楚了解的铁吸收和转运机制包括肠黏膜细胞对铁的摄取、铁在细胞内的转移、铁经基底膜转运到血液并经血液循环供机体组织细胞利用等几个环节。本文拟对铁在动物体内的吸收、转运及相关调节分子机制进行综述。     

外源性H2S对氯胺酮全麻大鼠主要生理指标的影响

外源性H₂S在诸多方面对中枢神经系统具有保护性作用,本研究通过预试验确定了外源性H₂S的给药时间和剂量,将48只SD大鼠随机均分为4组,分别为对照组（CP组）、低剂量组（LP组,7 μmol/kg NaHS）、中剂量组（MP组,14 μmol/kg NaHS）、高剂量组（GP组,28 μmol/kg NaHS）。在盐酸氯胺酮麻醉前20 min,3个剂量组分别腹腔注射7、14、28 μmol/kg NaHS,观察外源性H₂S对大鼠体温、心率、呼吸频率、血氧饱和度及血压等生理指标的干预效果。试验结果表明,与对照组相比,3个剂量组体温和血氧饱和度浓度均显著升高（P<0.05）,心率和血压均显著降低（P<0.05）,但呼吸频率呈先减慢后加快趋势,且这些变化呈显著的剂量依赖性。     

The influences of hyperbaric oxygen therapy with a lower pressure and oxygen concentration than previous methods on physiological mechanisms in dogs

Recently, hyperbaric oxygen therapy with a lower pressure and oxygen concentration (L-HBOT) than previous methods has been used for dogs in Japan; however, the influences of L-HBOT on dogs have not been clarified. To verify the influences of L-HBOT on physiological mechanism in dogs, we investigated blood gas parameters, glutathione peroxidase (GPx) activity, heart rate variability, stress-related hormones and skin conductance (SC) in 4 clinically normal beagle dogs with catheters in their carotid arteries and jugular veins when they were quiet, after running, after receiving L-HBOT (30% oxygen concentration, 1.3 atmospheres absolute, 30 min) or after not receiving L-HBOT. The results showed there were no changes in blood gas parameters, heart rate variability and catecholamine levels after L-HBOT. GPx activity was significantly higher, and the SC and cortisol level were lower in dogs that received L-HBOT than those when they were quiet. These results suggested that L-HBOT may have a small influence on oxygenation dynamics, activate antioxidant enzymes such as GPx, restrain autonomic nervous activity and control the balance between oxidation and antioxidation inside the body.     

Observations on some cardiopulmonary effects of midazolam, xylazine and a midazolam/ketamine combination in the goat

Xylazine, midazolam and a midazolam/ketamine combination were administered to 6 goats in a randomised 3-way block design. All goats received all treatments with at least a 7-day interval between treatments. Statistically significant (P < 0.05) changes were observed in some of the measured cardiopulmonary variables for xylazine and midazolam/ ketamine. Xylazine administration resulted in statistically significant decreases in minute volume, arterial partial pressure of oxygen, heart rate and mean arterial blood pressure. The increase in arterial partial pressure of carbon dioxide was not statistically significant. For the midazolam/ketamine combination, the decrease in tidal volume was statistically significant, but not the decrease in minute volume and increase in arterial partial pressure of carbon dioxide. The decrease in the arterial partial pressure of oxygen was also statistically significant. The mean arterial blood pressure for the combination was statistically significantly higher compared to xylazine. The changes in cardiopulmonary variables after midazolam administration were not statistically significant, such as tidal and minute volume, arterial partial pressure of oxygen and carbon dioxide. However, clinically significant effects such as hypoventilation and hypoxia were observed after its administration. The change in mean arterial blood pressure was minimal.