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1.
The ultrastructure of the Harderian gland of Atlantic bottlenose dolphin ( Tursiops truncatus ) was examined by scanning electron microscopy (SEM). We found the following surface features: the typical round appearance of the ascinar glandular unit with a finely granular surface, a thin cortex and immediately below two types of cells: type I cells (characterized by small lipid vacuoles) and type II cells (characterized by large lipid vacuoles). It has been suggested that different cells forms represent a single cell type in varying activity states. Additionally, a coalescent tubular complex, a small balloon-like structures and large globular structures were observed. These structures may be reservoirs of secretion products.  相似文献   

2.
From February 1997 till May 1998 the national reference laboratory for classical swine fever (CSF) in the Netherlands was confronted with millions of samples taken from pigs during an outbreak of CSF in a pig dense region. In a limited period major logistic problems needed to be solved regarding the processing of samples and information at the laboratory facilities.In total over 2.3 million samples were examined by different CSF diagnostic methods. The majority (approximately 2.1 million) of these samples were blood samples which were tested for CSF serum antibody in a semi-automated ELISA. Approximately 166,000 samples were examined for the presence of CSF virus or viral antigen. Automated preparation and testing of blood samples for CSF serum antibody, the obligatory identification and registration system of pig holdings and the computerised laboratory management system made it possible to process the huge amount of samples and information presented in a limited period. The majority of the test results was sent to the veterinary authorities via e-mail or a computerised fax system.Of the 429 outbreaks 82% were detected via a direct immunofluorescence technique performed on cryostat sections of the tonsil. The sampling of clinically suspected pigs ('guided' sampling) for this diagnostic method provided rapid positive and negative results and thus played a paramount role during the eradication campaign. Serological surveys identified 13.5% of the infected pig holdings: such surveys proved very effective in the screening of holdings which were subjected to restrictions (protection or surveillance zones) for many months. Virus isolation performed on different types of samples detected 4. 5% of the infected pig holdings.In conclusion, analysis of data collected in the laboratory and epidemiological analysis should result in an improved eradication plan for the future control of outbreaks of CSF in the Netherlands supported by optimised CSF diagnostic methods.  相似文献   

3.
Information pertaining to evaluation of single ejaculates of semen and records for 2 consecutive breeding seasons were obtained. In all, data for 99 individual breeding seasons (n = 43 Standardbreds and 56 Thoroughbreds) were evaluated. Included in each semen evaluation was examination of semen characteristics and computer-aided analysis of spermatozoal movement characteristics. On the basis of the analysis of breeding records for 4,175 mares (7,017 estrous cycles), a per-estrous cycle fertility rate was calculated from data for 96 of the breeding seasons. Stallions with lower fertility than the mean overall season fertility had significantly (P less than 0.01) lower mean values for subjective appraisal of the percentage of motile and progressively motile spermatozoa and for percentage of morphologically normal spermatozoa. Lower mean values were obtained for computer-aided movement analysis of the percentage of motile and progressively motile spermatozoa, and for mean velocity of motile spermatozoa. Semen characteristics, including spermatozoal movement characteristics, and fertility were significantly (P less than 0.05) correlated for Thoroughbred and Standardbred stallions when analyzed individually and when data for both breeds were combined. Characteristics most highly correlated (P less than 0.01) with fertility data for both breeds combined were: subjective appraisal of the percentage of motile (r = 0.40) and progressively motile (r = 0.46) spermatozoa; percentage of morphologically normal spermatozoa (r = 0.36); and computer-aided analysis of percentage of motile spermatozoa (r = 0.34). However, on the basis of evaluation of a single ejaculate for each stallion, the variation in these characteristics only accounted for approximately 20% of the observed variation in fertility rate.  相似文献   

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From winter 1997 to summer 1998, an epizootic of salmonellosis affected several species of songbirds over a large area of the eastern North American continent. This article describes the details of this epizootic in the Canadian Atlantic provinces, based on laboratory examination of dead affected birds and on suspected but unconfirmed cases of salmonellosis reported by members of the public. The common redpoll (Carduelis flammea) was the species most often affected, followed by pine siskins (C. pinus), purple finches (Carpodacus purpureus), evening grosbeaks (Coccothraustes vespertinus), and American goldfinches (Carduelis tristis). A poor body condition and necrotizing and fibrinopurulent esophagitis and ingluvitis were the most common gross lesions in these birds. Thirty-four of 35 isolates of Salmonella recovered from these birds were identified as phage type 40. Despite the magnitude of this and previous epizootics of salmonellosis among North American songbirds, the sources of these epizootics and the precise influence of environmental factors on their occurrence remain poorly understood.  相似文献   

6.
The analysis of breeding records and sperm morphologic classifications from ejaculated semen during 99 stallion seasons, over a 2-year period, revealed a significant correlation (r = 0.34, P less than 0.01) between the percentage of morphologically normal sperm in ejaculates and the per cycle fertility estimate of the stallions studied. In addition, the percentage of sperm classified as having major defects (abnormal heads, proximal droplets, and abnormal midpieces) was significantly inversely correlated (r = -0.36, P less than 0.01) with the same fertility estimates. Multiple variable regression demonstrated that the variation in 2 morphologic features classified as major defects, abnormal heads, and proximal droplets, accounted for the largest amount of variation in fertility. It appears that in stallions, a large percentage of ejaculated sperm with major defects or other defects in combination with major defects is associated with a larger reduction in fertility than is associated with other defects.  相似文献   

7.
Outbreaks of epizootic hemorrhagic disease of deer and of bluetongue began in British Columbia in August and October 1987 respectively and recrudescence of infection by both viruses was detected the following year in August. Weather records for up to 18 days before the initial outbreaks of disease, isolation of virus or seroconversion were examined to determine if the viruses could have been introduced by infected Culicoides carried on the wind. Data on temperature, rainfall, wind speed and direction and pressure together with backward trajectory analysis showed that there were suitable winds which could have introduced Culicoides infected with epizootic hemorrhagic disease of deer virus on 13 August 1987 (14 days before disease was observed), Culicoides infected with bluetongue virus on 1 October 1987 (7 days before virus was isolated and 13 days before disease in sheep) and Culicoides infected with bluetongue or epizootic hemorrhagic disease of deer viruses on 20 July 1988 (15 days before seroconversion was detected). The arrival on 13 August 1987 coincided with the passage of a cold front and rain and that on 1 October 1987 with a fall in temperature and calm winds. The source of the Culicoides before arrival could have been the Okanogan Valley as far south as the junction of the Okanogan and Columbia rivers in Washington, USA. Flight would have been at temperatures of 12.6 degrees C or higher and at heights up to 1.5 km.  相似文献   

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《African Zoology》2013,48(2):290-293
Notes on the synonymy of Hexapodibius beasleyi Maucci, 1988, with Haplohexapodibius seductor Pilato & Beasley 1987, are given. Ha. seductor Pilato & Beasley, 1987, is a new record for the African tardigrade fauna.  相似文献   

10.
The first two isolates of H9N2 influenza virus in Israel were collected from turkey and chicken hosts in May 2000. The actual epizootic of the H9N2 virus started in December 2001, after a 1.5-year period of silence, and still continues. A total of more than 500 isolations from turkeys and chickens were registered during the outbreaks. The present study has revealed some genetic peculiarities among the local isolates, namely: all the isolates belong to the same G1-like phylogenetic lineage, within which they form a single group, which, in turn, is divided into three subgroups in the cases of the HA and NP genes, and two subgroups in the case of the NA gene. The results present a basis for suggesting the existence of two parallel evolutionary trends originating from the same local "prototype" isolate.  相似文献   

11.
Medical records of 66 dogs that had undergone myelography, using iohexol (240 mg of iodine/ml, 0.3 to 0.5 ml/kg of body weight) during a 2-year period, were reviewed. In 3 dogs, myelography was performed twice during different anesthetic procedures. Neurologic abnormalities were more pronounced the day after myelography in dogs with caudal cervical spondylomyelopathy (P less than 0.01), meningitis (P less than 0.01), or extradural tumors (P less than 0.05). Neither anesthetic regimen nor duration of anesthesia significantly affected the frequency of complications. Seizures occurred after myelography in 6 dogs, and 1 dog had seizures after each of 2 myelographic procedures. The frequency of seizures was significantly greater in male Doberman Pinschers afflicted with caudal cervical spondylomyelopathy. Male dogs (P less than 0.01) and Doberman Pinschers (P less than 0.001) had higher prevalence of seizures. Caudal cervical spondylomyelopathy was associated with higher prevalence of seizures, compared with all other diagnoses (P less than 0.001). Seizures were significantly more prevalent when body weight was greater than or equal to 29 kg (P less than 0.001), when greater than or equal to 2 injections of contrast medium were administered (P less than 0.016), or when 2 injections of contrast medium were given at the cisterna magna (P less than 0.015). The 10% prevalence of seizures after myelography with iohexol in the study reported here is greater than in previous reports, but is lower than that reported after myelography using metrizamide.  相似文献   

12.
OBJECTIVE: To determine in vitro susceptibility patterns of fungi associated with keratomycosis in horses in the northeastern United States and compare those patterns with results of studies from other geographic regions. DESIGN: Retrospective case series. ANIMALS: 68 horses with keratomycosis. PROCEDURES: Medical records of horses with a clinical diagnosis of keratomycosis, positive results of corneal fungal cultures, and susceptibility data were reviewed from the years 1987 to 2006. Fungal identification and in vitro antifungal susceptibility test results were recorded. The percentage of susceptible isolates was compared among antifungals for all isolates together and for the most common genera individually. RESULTS: 74 fungal isolates from 68 horses that met inclusion criteria were identified. Aspergillus, Candida, and Fusarium spp were the most frequent isolates. Grouped isolates had the highest percentage of susceptibility to nystatin (87.7%), natamycin (87.5%), and clotrimazole (80.6%). Grouped isolates had the lowest percentage of susceptibility to fluconazole (15.8%) and miconazole (27.5%). Aspergillus spp (> or = 81.0%) were most susceptible to nystatin, clotrimazole, itraconazole, and natamycin. Candida spp (100%) were most susceptible to ketaconazole, natamycin, and nystatin. Fusarium spp (100%) were only consistently susceptible to natamycin. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of in vitro susceptibility testing, nystatin, natamycin, or clotrimazole is recommended for initial topical treatment of keratomycosis in horses from the northeastern United States. Contrary to results of studies of ocular fungal isolates of horses from other regions, Candida spp were identified more frequently and miconazole had lower in vitro efficacy in the present study.  相似文献   

13.
Radiographic and surgical findings were compared in 123 cattle suspected of having traumatic reticuloperitonitis. Radiography of the reticulum proved to be a sensitive test for detection of a foreign body (FB). An abnormal FB position on a radiograph was a good predictor of FB perforation. If an FB was fully attached to a magnet, it was unlikely to be perforating the reticular wall. When abnormal reticulum size, abnormal reticulum location, and gas shadows adjacent to the reticulum were found simultaneously on a radiograph, hepatic or perireticular abscess was likely. Reticular radiography proved to be a useful diagnostic aid in cattle suspected of having traumatic reticuloperitonitis.  相似文献   

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Thirteen dogs with encephalomyelitis attributable to canine distemper virus infection were classified into 3 groups on the basis of histopathologic evidence of virus-induced lesions in CNS tissue. Analysis of data indicated a similarity within groups when arranged by age, clinical neurologic signs, and alterations in the CSF electrophoretic protein values. Comparison with results in dogs with experimentally induced canine distemper encephalomyelitis suggested that when grouped by age, CSF electrophoretic values are helpful in predicting the CNS histopathologic changes in dogs with naturally acquired canine distemper encephalomyelitis.  相似文献   

16.
基于1982-2015年间GIMMS NDVI3g数据、气象数据和植被类型数据,采用趋势分析、偏相关性分析和残差分析等方法,从不同时空尺度上分析蒙古国植被NDVI空间格局、变化趋势及其主要原因.结果表明,过去34年间蒙古国生长季平均NDVI在空间上由南向北逐渐增加,具有显著的纬度地带性分布特征,并随着海拔的升高而降低....  相似文献   

17.
We conducted a matched case-control study to evaluate risk factors for infection with highly pathogenic avian influenza (HPAI) H5N1 virus in poultry farms during the epidemic of 2006-2007 in Nigeria. Epidemiologic data were collected through the use of a questionnaire from 32 case farms and 83 control farms. The frequency of investigated exposure factors was compared between case and control farms by using conditional logistic regression analysis. In the multivariable analysis, the variables for (i) receiving visitors on farm premises (odds ratio [OR]=8.32; 95% confidence interval [CI]=1.87, 36.97; P<0.01), (ii) purchased live poultry/products (OR=11.91; 95% CI=3.11-45.59; P<0.01), and (iii) farm workers live outside the premises (OR=8.98; 95% CI=1.97, 40.77; P<0.01) were identified as risk factors for HPAI in poultry farms. Improving farm hygiene and biosecurity should help reduce the risk for influenza (H5N1) infection in poultry farms in Nigeria.  相似文献   

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