首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
单殖吸虫是一种重要的鱼类寄生虫。为了有效控制单殖吸虫病和减少药物对环境的污染,生态防控或将成为一种重要的防控手段,而了解环境因子对单殖吸虫的影响则可为生态防控提供准确信息。文章就水温和光照对单殖吸虫的影响进行了综述。  相似文献   

2.
Abstract

A poorly differentiated subcutaneous neoplasm occurred in a white bass Morone chrysops collected from a freshwater lake in Oklahoma. The neoplasm was a solitary soft round mass that bulged from the anal fin. Histologically, the neoplasm was lobular and consisted of islands of spindle-to- stellate cells separated by clefts. The islands frequently contained capillary profiles and deposits of an amorphous eosinophilic material. The lesion was mesenchymal and suggestive of a poorly differentiated hemangiopericytoma, though it might have derived from nerve sheath, pigment cells, fibroblasts, or smooth muscle. An epizootic of another type of dermal neoplasm, a poorly differentiated spindle cell tumor, has been reported in gizzard shad Dorosoma cepedianum residing in the same lake. However, etiology of the neoplasms from both the white bass and the shad remains uncertain.  相似文献   

3.
The clinical, pathological and virological findings in puppies affected with myocarditis are reported. A parvo-like virus was isolated from pooled heart specimens, which is similar to the virus isolated from gastroenteritis cases.  相似文献   

4.
Abstract

Largemouth bass virus (LMBV) is an iridovirus that was isolated from wild adult largemouth bass Micropterus salmoides in the southeastern United States in 1994. Although originally isolated from moribund wild fish, its virulence to juvenile largemouth bass is uncertain. To help clarify this point, two LMBV titrations were made in juvenile largemouth bass. Titers of LMBV in fathead minnow cells were 104.8 and 105.8 tissue culture infectious doses—50% cytopathic endpoint (TCID50) per milliliter, respectively. Tenfold serial dilutions of LMBV employed in each cell culture titration, injected intraperitoneally (0.1 mL/fish) into largemouth bass produced calculated lethal dose—50% mortality endpoints (LD50s) of 282 (102.45) and 288 (102.46) infectious doses in two consecutive infectivity trials. Virus yield of assayed infected fish averaged 108.5 TCID50/g and 107.7 TCID50/g in viscera of moribund and dead fish in the two trials and 106.5 TCID50/g in surviving exposed fish 14 d after infection. In a second experiment, largemouth bass had 100% mortality 5 d after injection while virus immersed fish had a significantly (P ≤ 0.005) lower mortality of 17% at 14 d. Similarly treated juvenile striped bass Morone saxatilis suffered 63% mortality after injection and significantly (P ≤ 0.005) lower mortality of 10% after immersion. In a third study of 25 d, 100% of injected largemouth bass died by 5 d after injection, and all of them were virus-positive. Injected striped bass had a significantly (P ≤ 0.005) lower mortality of 24%; all three fish were virus-positive initially, two fish were virus-positive at 18 d, and none were positive at 25 d. Juvenile largemouth bass were highly susceptible to LMBV injection and striped bass were moderately susceptible, but both species were only mildly susceptible when exposed by immersion.  相似文献   

5.
Abstract

Largemouth bass virus (LMBV; family Iridoviridae) has recently emerged as a causative agent in fish kills of largemouth bass Micropterus salmoides. Little is known about how the virus is transmitted or what factors predispose fish to mortality subsequent to infection. Concern has nevertheless arisen that activities related to recreational angling may affect transmission dynamics and may alter the susceptibility of infected fish to clinical disease. This study examined the separate effects of two angling-related factors on the susceptibility of juvenile largemouth bass to mortality from LMBV infection and on the transmission of LMBV from infected to uninfected fish. The first factor was hook-and-line angling. Infected fish that underwent a simulated angling treatment did not experience higher mortality or have higher viral loads in their tissues than those that were not angled. The second factor was direct contact between infected and uninfected fish, as would occur in live wells and holding tanks. The LMBV was transmitted from infected to uninfected fish through water, even when direct contact was prevented. Transmission of LMBV between infected and uninfected fish separated by a fenestrated barrier was nearly as efficient as LMBV transmission between infected and uninfected fish that were allowed direct contact. These results imply that angling itself may have only minimal effects on the survival of largemouth bass infected with LMBV but that angling-related practices that place infected and uninfected fish together in a limited water volume may facilitate viral transmission. Partitioning or cooling of live wells and holding tanks, as well as limiting their use, could reduce LMBV-associated mortality and viral transmission.  相似文献   

6.
近年来,许多经MD疫苗免疫的鸡场,陆续发生以马立克氏病症状死亡的鸡只。本次该鸡场发生的疫情比较严重,通过临床和病理学检查,确诊死于马立克氏病。根据最新研究资料认为,发病的原因与疫苗的接种时间有关。  相似文献   

7.
Abstract

We examined male shoal bass Micropterus cataractae from the Flint River, Georgia, to determine the prevalence of intersex. During March and April 2010, we sampled 61 shoal bass from six sites along the Flint River. Testes were examined histologically and classified as intersex if the presence of oocytes was noted. Using a severity index, we compared samples collected on different dates and from different locations according to age and testis weight. No significant variations were noted among any of the groupings. Further investigation is needed to determine whether the intersex condition in shoal bass is severe enough to warrant concern and whether it is a natural phenomenon.

Received January 20, 2011; accepted July 22, 2011  相似文献   

8.
On assessment for use in an AI stud, a 12‐month‐old bull was found to produce low volume ejaculates with 41% of the sperm having morphological abnormalities. No left epididymal tail was palpable and the head of the epididymis on the left was twice the size compared with the right. Ultrasound examination showed the left testis to contain a large central area of decreased echogenicity, which could be followed proximally to a 15‐mm echolucent lesion at the site of the epididymal head. Postmortem examination revealed a 15‐mm diameter cyst in the region of the left epididymal head, and absence of the body and tail of the epididymis. The mediastinum testis of the left testis was dilated, corresponding to the area of decreased echogenicity observed on ultrasonography. No left seminal vesicle was present and the ampulla was significantly smaller than the same structure on the right. Histological examination revealed incomplete or absent spermatogenesis involving the majority of seminiferous tubules in the left testis, and a small proportion of those of the right testis. The cystic structure at the site of the left epididymal head was lined by irregular, sometimes attenuated, epithelium and contained sparse spermatozoa. This case demonstrates the adverse impact, which segmental aplasia of the mesonephric duct had on the testicular and epididymal function of a bull, and highlights the importance of careful clinical assessment in its diagnosis.  相似文献   

9.
The body length and diameter of muscle fibres from the right hypaxial tail myomeres were measured in 100 sea bass larvae (Dicentrarchus labrax, L.) at ages of 40 to 90 days, from a fish farm in Croatia. The larvae were kept at a temperature of 19-20 degrees C and fed with standard feed for their respective ages. Body lengths of larvae 40-90 days old varied from 8 to 42 mm, increasing significantly in 10-day intervals (p < 0.001), except between days 50 and 60 when there was no increase in the body length. The measured diameters of muscle fibres ranged from 10 to 80 microm, the mean value increasing except between days 50 and 60. The fibre diameter in larvae aged up to 60 days was 10-40 microm, while that in larvae older than 70 days was 51-80 microm. In 90-day-old larvae there were no fibres of 10-20 microm in diameter; however, the number of fibers of 61-80 microm diameter increased. A statistically significant concordance was determined between the body length and fibre diameter of larvae 70 to 90 days old. Between days 50 and 60, arrested growth of the larval body and corresponding decrease in fibre diameter was observed. From day 45 until days 59, larvae were fed with Artemia nauplii and microparticles of formulated diets. From the day 60, minced fish was added to formulated diets. This change in diet probably resulted in the observed growth arrest.  相似文献   

10.
Abstract— The clinical, histopathological and ultrastructural features of a spayed female Siamese cat with a three-and-a-half year history of progressive cutaneous depigmentation are described. Clinically the condition was characterised by progressive leukoderma of the nose, pinna and footpad skin, and multifocal leukotrichia involving the whole body. Histopathological and ultrastructural studies confirmed the absence of melanocytes and melanin in the epidermis and hair follicles of affected areas. Immunohistochemical study revealed areas with absence of immune response to anti-vimentin antiserum, which was interpreted as a loss of dendritic cells, especially melanocytes. Diagnosis of vitiligo was based on the clinical signs and pathological features. This study adds a new case of this uncommon condition in the cat, and documents some previously non-reported features of feline vitiligo, such as the chronic progressive and generalised nature of the skin lesions, and its reversible character with partial lentiginous repigmentation on the pinna.  相似文献   

11.
由于在饲料中使用劣质的骨粉和未经脱氟处理的磷酸氢钙作为钙磷补充剂,我国许多地区出现了大量氟中毒病例。河北省玉田县某养鸡户因饲料中添加从当地市场购买的劣质磷酸氢钙引起鸡大批死亡。为确诊其中毒原因,我们特进行了鸡中毒试验,并对饲料中添加的磷酸氢钙中氟含量进行了检测。  相似文献   

12.
Abstract— —Clinical and pathological observations on an 8-year-old male Alsatian dog suffering from a brain tumour are described. The symptoms included running to and fro, whining, salivation, hiding in dark corners, a swollen blood-shot right eye, paresis of the hind legs, ataxia, anorexia, and holding of the head to the left side. At necropsy a tumour measuring 1 cm in dia. was found in the posterior part of the left olfactory tract. There was a moderate unilateral hydrocephalus of the left lateral ventricle and a tear through the septum pellucidum. Microscopically the tumour was diagnosed as astrocytoma. Résumé— —Observation clinique et pathologique concernant un chien alsacien âgé de 8 ans présentant une tumeur cérébrale. Symptomes: l'animal est agité, gémit, salive, se cache dans l'obscurité; l'oeil droit est enflé, injecté de sang; parésie des membres postérieurs, ataxie, anorexie; le chien tient la tite penchée vers la gauche. La nécropsie a révélé une tumeur d'un diamètre de I cm, située dans la partie postérieure de l'appareil olfactif gauche; ont été constatées en outre une hydrocéphalie modérée du ventricule latéral gauche et une lésion du septum pellucidum. L'analyse microscopique a permis de diagnostiquer un astrocytome. Zusammenfassung— —Klinische und pathologische Beobachtungen an einem 8 jährigen Schäferhundrüden, der an einem Gehirntumor litt, werden beschrieben. Zu den Symptomen gehörten Hin- und Herlaufen, Wimmern, Speichelfluss, Verstecken in dunklen Ecken, ein geschwollenes, blutunterlaufenes rechtes Auge, Lähmung der Hinterbeine, Ataxie, Anorexie und Schief haltung des Kopfes nach der linken Seite. Die Sektion ergab einen Tumor von 1 cm Durchmesser im hinteren Teil des linken Olfaktoriustraktes. Es bestand ein rnässiger einseitiger Hydrocephalus des linken Seitenventrikels und eine Zerreissung des Septum pellucidum. Mikroskopisch wurde der Tumor als Astrozytom diagnostiziert.  相似文献   

13.
West, H.J., 1997. Clinical and pathological studies in cattle with hepatic disease. Veterinary Research Communications, 21 (3), 169-185In cattle with hepatic lipidosis, hepatic abscessation, leptospirosis, biliary calculi or fasciolosis, the progression of the disease was studied by serial measurements of serum total bile acid concentrations, plasma glutamate dehydrogenase, -glutamyltranserase, 5-nucleotidase and leucine aminopeptidase activities Terminalia avicennioides and by liver biopsy. Regardless of the cause of the hepatic disease, weight loss, anorexia, dullness and depression were consistent features. Signs of hepatic encephalopathy, such as blindness, head pressing, excitability, ataxia and weakness were less common and, together with pyrexia and jaundice, were grave prognostic signs. Plasma ammonia concentrations were significantly elevated compared to clinically normal cattle, but such changes were not always accompanied by a decline in plasma urea concentrations. In normal, healthy cattle, the plasma ammonia:urea concentration ratio is 9:1 and the plasma ammonia:glucose concentration is 11:1. In hepatic disease, a plasma ammonia:glucose ratio >40:1 or plasma ammonia:urea ratio >30:1, particularly with a rising total ketone body concentration and a declining glucose concentration, carried a guarded prognosis. The study suggested that other factors, such as hypokalaemia, alkalosis, short-chain volatile fatty acids, and false and true neuro-transmitters, may be important in the pathogenesis of hepatic coma in cattle.  相似文献   

14.
Clinical and Pathological Features of Aortic Thromboembolism in 36 Dogs   总被引:1,自引:0,他引:1  
Thirty-six dogs with aortic thromboembolism were identified in a retrospective study conducted using case material from the small animal necropsy service of the University of Pennsylvania, from 1977 through 1992. No age, breed, or sex predisposition was found. Thirty dogs presented with primary complaints referable to the aortic thromboembolus and the duration of signs varied from hours to months. In 16 dogs, the presence of the thromboembolus was confirmed antemortem by ultrasound or angiography. Coagulograms were performed in 11 animals, and were consistent with consumptive hemostatic disorders in 8. The aortic occlusions were determined to be emboli in 11 dogs, associated with cardiac disease (9 dogs) and neoplastic emboli (2 dogs). In 18 dogs, the aortic occlusions were determined to be caused by primary aortic thrombi. Nine of these dogs had renal disease and four dogs had severe atherosclerosis associated with thyroid disease. In seven dogs, it could not determined if the aortic occlusions were due to primary aortic thrombi or due to emboli. In 25 dogs, the aorta was the only vessel occluded; but in 11 dogs, thrombi were identified in vessels outside of the systemic arterial system. In 9 dogs, the pulmonary arteries contained thromboemboli; one dog had thrombi in the portal vein and pulmonary arteries, and one dog a cranial vena caval thrombus. Nine of 11 dogs with multiple vascular thrombi, as well as some of the dogs with primary aortic thrombi, may have had either a propensity for thrombosis (a hypercoagulable state) or an inability to lyse thrombi (a hypothrombolytic state).  相似文献   

15.
We report the case of a bilateral and multilocular spermatocele and sperm granuloma in a dog that was vasectomized 5 years before. Clinical examination revealed scrotal dermatitis and benign prostatic hyperplasia. Orchiectomy was performed, and gross and histological examination showed testicular degeneration associated with epididymal sperm granuloma. In relation to this case, the literature about long-term effects of vasectomy in dogs has been reviewed. On the basis of these results, a preventive sonogram and physical assessment in prostate and other reproductive structures before vasectomy is recommended.  相似文献   

16.
The length of incubation for 36 eight and 12 week old swine in eight experimental passages averaged 11 days and ranged from five to 24 days. The duration of diarrhea for 24 of these swine averaged 6.4 days and ranged from two to 19 days. The consistent macroscopic lesion was a colitis and, subsequently, a typhlitis. In the swine euthanized on the first day of diarrhea, the colitis was most intense in the coils near the apex of the colon and, frequently, these swine had a hyperemia of the fundus of the stomach. The amount of visible blood in the colon varied. Organisms identified microscopically and ultrastructurally as spirochetes were observed commonly in the feces and the mucosal glands of the colon of swine with a diarrhea, but not in the adjacent mesenteric lymph nodes. These spirochetes which were the most numerous on the first day of diarrhea, could not be isolated and propagated in vitro. Swine which recovered naturally or were medicated at the height of a diarrhea, developed a resistance to swine dysentery. Colon from infected swine remained infectious when stored at -77°C for nine months but not when stored at -16°C. Feces from infected swine were not infectious after lyophilization and storage at -12°C.  相似文献   

17.
选取平均体重3.5 g的加州鲈300尾,随机分为2组,每组3个重复,每个重复50尾,试验期56 d。结果表明:①用鸡肠膜蛋白等比例替代鱼粉(3%替代)可以增加加州鲈末重和降低饵料系数(P>0.05)。②肠膜替代鱼粉可显著提高加州鲈肠道胰蛋白酶、糜蛋白酶和脂肪酶活力(P<0.05)。③肠膜组可以显著降低血液中丙二醛(MDA)、谷草转氨酶(AST)和谷丙转氨酶(ALT)的活力,提高血液中总抗氧化能力(T-AOC)以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(Gpx)的活力(P<0.05)。④肠膜蛋白组可以显著降低肝脏中脂肪含量(P<0.05),这与肝脏HE染色以及油红O染色结果一致。上述结果显示,用肠膜蛋白等比例替代鱼粉可以通过提高肠道消化酶活力,提高肠道和肝脏健康,从而促进加州鲈生长。  相似文献   

18.
Inoculations of vixens with Encephalitozoon cuniculi (E. cuniculi), performed orally, either before or in the gestation period, or directly into the uterus at oestrus, induced clinical encephalitozoonosis in the offspring. The infection of the vixens, indicated by a general E. cuniculi antibody response, appeared to run a subclinical course. Endometritis was detected in some of the vixens when examined at the end of the trial. A temporary increase of total protein, albumin and globulin in the inoculated vixens compared to the controls was detected in the final 2 weeks of the gestation, concomitantly with the rise in humoral E. cuniculi antibody titres. The antibody levels appeared significantly higher in the group of vixens inoculated directly into the uterus than in the orally inoculated groups. Vixens exposed to the parasite seemed to possess a certain degree of acquired resistance to re-infection with the parasite when exposed in the following breeding season.  相似文献   

19.
Abstract

The largemouth bass virus (LMBV) was characterized in cell culture, by infectivity in five cell lines of fish origin, optimum replication temperature, and ether and pH sensitivity. Viral induced cytopathic effect (CPE) appeared most rapidly in bluegill fry-2 (BF-2) and fathead minnow (FHM) cell lines where the optimum temperature for LMBV replication was 30°C. In a one-step growth curve in BF-2 cells, LMBV reached 108.6 TCID50/mL (±0.12 log SD) in 24 h. The virus showed reduced infectivity when treated with ether but was stable when held in medium with a pH 3–9 for 12 h at 4°C. These characteristics further support the classification of LMBV in the family Iridoviridae.  相似文献   

20.
本文旨在通过研究酵母酶解物对大口黑鲈(Micropterus salmoides)生长性能、脂类代谢及肠道组织结构的影响,来评价酵母酶解物在大口黑鲈饲料中的有效性。配制3种等蛋白质(粗蛋白质47%)等能(总能20.0 MJ/kg)的饲料:以含35%低温干燥鱼粉的高鱼粉饲料为对照饲料(命名为FM),在此基础上以混合植物蛋白质(豆粕+谷朊粉)替代50%的鱼粉并平衡必需氨基酸后作为基础饲料(命名为SBM),另在基础饲料中添加3%的酵母酶解物作为试验饲料(命名为HY)。选用初始体重为(20.80±0.04)g的健康大口黑鲈为试验对象,随机分为3组,每组4个重复,每个重复25尾,在室内循环控温系统中进行8周生长试验。结果表明:在增重率、特定生长率、摄食率上,HY组显著高于FM和SBM组(P0.05);在肝体比上,HY组显著低于FM和SBM组(P0.05)。FM组的全鱼粗脂肪含量显著低于HY和SBM组(P0.05)。HY和SBM组大口黑鲈血清高密度脂蛋白胆固醇含量显著高于FM组(P0.05),而肝脏总胆固醇含量则显著低于FM组(P0.05)。血清甘油三酯和游离脂肪酸含量及肝脏脂肪含量变化一致,即FM组显著低于SBM组(P0.05),与HY组无显著差异(P0.05)。用混合植物蛋白质替代50%鱼粉后,大口黑鲈肠道肌层变薄,绒毛完整齐度下降,在此基础上添加酵母酶解物后,肠道结构损伤的情况有所缓解。由此得出,在本试验条件下,用混合植物蛋白质替代50%鱼粉后添加3%的酵母酶解物能够提高大口黑鲈的生长性能,改善肝脏状态,促进肝脏脂肪和胆固醇的代谢,修复肠道损伤。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号