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1.
In late 1996 in France, a severe digestive disease appeared in fattening domestic rabbits. Named the Epizootic Rabbit Enteropathy (ERE), this digestive syndrome has become the main cause of mortality in rabbit farming. The diagnosis in field conditions is difficult because co-infection with other common rabbit pathogens is frequent. By using specific pathogenic free (SPF) rabbits and starting from a field sample of intestinal contents of diseased animals, a virulent material (inoculum) was obtained free of almost all known pathogens but reproduced the symptoms and lesions of ERE. Four hundred and seven SPF rabbits were used in five trials to describe the disease. ERE is characterized by a high contagiousness, 30 to 40% mortality in a few days and about 100% morbidity whatever the dose of the inoculum used. Clinical signs and lesions evolved acutely with the first sign (rambling noise) appearing one day after inoculation and the disease peaking 4 to 6 days later. Growth was strongly lowered from the second day to the end of the second week. Rambling noise and distended abdomen were frequent, mucus excretion and cecal impaction were frequent but not constant. ERE at necropsy was characterized by the absence of any inflammatory or congestive lesions on the gut or on other organs but with the typical presence of a stomach and/or duodenum dilated by liquid and gas and by the absence of specific histological lesions. The etiological agent has not been identified yet, but we demonstrate that the intestinal content was infectious as early as the second day. This work constitutes the experimental basis for studies on this emerging disease within the framework of etiological research led in different European laboratories working with the infectious material. 相似文献
2.
Epizootic rabbit enteropathy (ERE) emerged and spread in Europe within the last 13 years causing major economical loss. The
aims of the study was to evaluate antibiograms of TEC4, an inoculum composed of an extract of intestinal content of affected
rabbits, and to test the potential of different antibiotic-based TEC4 fractions to reproduce the disease. Twenty nine different
antibiotic discs were incubated for determining bacteria resistance. In a complementary study, nine tubes of liquid medium
were inoculated with TEC4, incubated and added individually with amoxicillin/clavulanic acid, bacitracin, ceftiofur, doxycycline,
novobiocin, streptomycyin, tylosin, vancomycin and 0.9% saline solution as control. The content of each tube was washed by
centrifugation and suspended in saline. The three most effective antibiotics are florfenicol, amoxycillin/clavulanic acid
and tylosin. A high concentration of Clostridium sordelli and Bacillus firmus were isolated in all fractions. Species never cultured from TEC4 were identified as Fusobacterium necrogenes (in vancomycin fraction), Cellulomonas sp (in novobiocin fraction) and Bacteroides distasonis (in doxycycline fraction). The ERE was reproduced when bacitracin, doxycycline and 0.9% fractions were inoculated. Rabbits
showed ERE clinical signs with the specific drop in daily weight gain. 相似文献
3.
Marlier D Dewrée R Lassence C Licois D Mainil J Coudert P Meulemans L Ducatelle R Vindevogel H 《Veterinary journal (London, England : 1997)》2006,172(3):493-500
Epizootic rabbit enteropathy (ERE), a highly lethal (30-80% mortality) disease of broiler rabbits aged 6-14 weeks, first appeared in 1997 in French intensive enclosed rabbitries and is of unknown aetiology. Bacteriological, virological and parasitical examination of the intestinal contents of rabbits that had died either in spontaneous field cases or after experimental reproduction of ERE, were undertaken in an attempt to identify infectious agents that may play a role in the disease. Two bacterial strains, Clostridium perfringens and non-enteropathogenic Escherichia coli were repeatedly isolated at high faecal counts from naturally infected animals. In field cases, a correlation between typical gross lesions of epizootic enteropathy and the presence of the alpha toxin of Cl. perfringens was observed (P<0.0001; Chi-squared test). Although attempts to reproduce the disease by inoculation with different pools of cultivable bacterial strains failed, the disease was successfully reproduced by inoculation with one French and two Belgian samples of caecal contents. 相似文献
4.
S. Le Bouquin J.L. Jobert G. Larour L. Balaine F. Eono S. Boucher A. Huneau V. Michel 《Livestock Science》2009,125(2-3):283-290
Epizootic Rabbit Enteropathy (ERE) is a severe clinical syndrome of rabbits causing high economic losses for farmers. ERE first appeared in France in 1996. A retrospective case–control survey was carried out to identify the risk factors of acute expression of ERE, after weaning, in 96 kindling-to-finish rabbit farms in western France during 2001 and 2002. Farm status was defined according to the expression of clinical signs of ERE and mortality rates in the last five broiler rabbit batches. Comparisons of structural characteristics, rearing conditions and herd management showed that the risk factors for acute ERE expression were late weaning (rabbit age at weaning ≥ 35 days, RR = 4.44, 95% CI [1.36–21.71]), transfer of young rabbits at weaning (young rabbit transfer or combined practice RR = 2.83, 95% CI [1.16–9.33]), and high volume of the fattening room (air volume/rabbit weight in fattening room at weaning ≥ 0.14m3/kg, RR = 2.98, 95% CI [1.29–8.42]) and a high mortality rate in young rabbits before weaning (i.e. rate ≥ 10.5%; RR = 2.18, 95% CI [1.20–3.53]). 相似文献
5.
Viral haemorrhagic disease in rabbits: A review 总被引：5，自引：0，他引：5
An acute haemorrhagic disease of rabbits was first reported in a southern province of China in 1984. It subsequently spread rapidly to South China and some parts of North China. The disease is characterized by an acute onset with fever, rapid respiration and sudden death. There is a high morbidity and mortality rate. The pathological changes are consistent with severe generalized circulatory dysfunction (hyperaemia, congestion and haemorrhage), marked degeneration of parenchymatous tissue, pronounced serous-haemorrhagic pneumonia and extensive disruption of reticulo-lymphoid tissue. The disease has been named rabbit viral haemorrhagic disease and it has been suggested that the aetiological agent is a picornavirus. A tissue-derived vaccine has been prepared by homogenizing the liver, lung, spleen and kidney of infected rabbits and inactivating with formaldehyde. This review summarizes the information on the aetiology, epidemiology and clinical and pathological aspects of this new rabbit disease. 相似文献
6.
Ferreira PG Dinís M Costa-E-Silva A Aguas AP 《Veterinary immunology and immunopathology》2008,121(3-4):364-369
Calicivirus infection of adult rabbits induces the so-called rabbit haemorrhagic disease (RHD) that kills 90% or more of the infected animals; in contrast, young rabbits (up to 8-week-old animals) are resistant to the same infectious agent. We report that calicivirus inoculation of young rabbits induced moderate titres of antiviral antibodies. When these rabbits reached adulthood, a second calicivirus inoculation resulted in resistance to RHD and boosting of antibody titres in half of the rabbits. Adoptive transfer of sera from calicivirus-infected young rabbits to na?ve adult rabbits conferred resistance to RHD. We conclude that calicivirus infection of young rabbits induces specific anti-calicivirus antibodies that will protect them from RHD when they reach adulthood. 相似文献
7.
Synergistic effects of toxic fractions of Fusobacterium necrophorum were examined for evaluation of the role of the toxin in inducing liver abscesses in rabbits. Cytoplasmic and culture supernatant fractions of F necrophorum had preparative activity for the Shwartzman reaction, and lipopolysaccharide of F necrophorum had preparative and provocative activities for the reaction. All 3 fractions were hepatotoxic. Inoculation into the bile duct with each fraction followed by intravenous inoculation with F necrophorum or Escherichia coli lipopolysaccharide had a greater synergistic effect in inducing severe hepatic necrosis than did inoculations with double doses of the cytoplasmic or supernatant fractions of F necrophorum. This synergism may have been attributable to the Shwartzman reaction. 相似文献
8.
9.
Luzia Teixeira Raquel M. Marques Artur P. Águas Paula G. Ferreira 《Research in veterinary science》2011,91(1):164-166
Rabbit Haemorrhagic Disease Virus (RHDV), a member of the Caliciviridae family, is the etiologic agent of Rabbit Haemorrhagic Disease (RHD); this viral disease is highly contagious and kills more than 90% of infected adult rabbits. Research on experimental calicivirus infection uses inocula obtained from livers of rabbits dying from calicivirus infection. This implies that caliciviruses have to be purified from liver homogenates. Current methods to isolate caliciviruses from rabbit livers are time consuming. We propose here a new procedure for fast purification of rabbit caliciviruses from liver homogenates that uses centrifugation through an iodixanol gradient. This method offers in approximately 2 h a sample with a high degree of calicivirus purity, as shown by its biochemical and immunocytochemistry analysis, which is also able to kill adult rabbits from RHD within 48 h of inoculation. 相似文献
10.
Picobirnaviruses are a novel group of viruses recently found in the faeces of several species of vertebrates. Examination by polyacrylamide gel electrophoresis of rabbit faecal samples collected in one animal facility revealed the viruses in 23 (11 per cent) of 211 samples. Further analysis by electron microscopy and caesium chloride isopycnic centrifugation confirmed the presence of picobirnaviruses in the samples. The oral inoculation of three newly weaned rabbits with purified virus resulted in the excretion of a virus with an electropherotype similar to the inoculum, by two of the three inoculated animals. Maximal viral shedding was detected 13 days after inoculation. No sign of diarrhoea was observed either in the inoculated animals or in the virus excreting animals surveyed. No antibody activity could be detected in the paired serum samples taken from the inoculated animals. 相似文献
11.
J F Prescott 《Veterinary pathology》1978,15(2):237-248
An outbreak of severe diarrhoea and death in young rabbits was associated with many nonenterotoxigenic Escherichia coli in the caecum. The severe clinical, pathological and bacteriological features of the diesase, acute diarrhoea associated with typhlitis and many E. coli in the caecum, could be reproduced either by the intraintestinal inoculation of many bacteria recovered aerobically or anaerobically from the caecum of these rabbits or by the intestinal inoculation of large numbers of a serogroup of E. coli, 0153, recovered from the caecum. Further experiments showed that this serogroup of E. coli, as well as a nonenteropathogenic serotype recovered from human faeces, would cause typhlitis and diarrhoea if inoculated in large numbers into the jejunum; pathological changes also were seen in the liver and kidney. Similar changes also could be induced by intravenous inoculation of a freeze-thaw (endotoxic) extract prepared from these strains. Any factor that allows rapid multiplication of E. coli in the rabbit caecum may be followed by absorption of endotoxin and subsequent typhlitis and so metimes by severe diarrhoea; this effect is seen in some field cases of diarrhoea in the rabbit. 相似文献
12.
Ferreira PG Costa-e-Silva A Monteiro E Oliveira MJ Aguas AP 《Research in veterinary science》2004,76(1):83-94
Young rabbits are naturally resistant to rabbit haemorrhagic disease (RHD) caused by the same calicivirus that kills, within 3 days, nearly all adult animals. We have investigated changes in blood leukocytes, and in the morphology and biochemistry of the liver (the organ where caliciviruses replicate) of young rabbits undergoing benign infection by the RHD virus. Four-week-old rabbits were infected with a calicivirus inoculum having a titre of 2(12) haemagglutination units either sacrificed 18, 24, 48 and 72 h later, or kept for follow-up studies up to 21 days after inoculation. The infection caused an acute and transient decrease in blood heterophils, and sustained enhancement in hepatic transaminases. Inflammatory infiltrates of the liver were seen in all animals after 24 h of infection; they had a predominant midlobular location. Hepatocytes could present different degrees of cell damage, including cell death; these lesions were limited to the liver cells located around the inflammatory infiltrates. Liver transaminases peaked 24-48 h after calicivirus infection; this was the same timing when liver infiltration and hepatocyte damage were more evident. No alterations of other parameters of liver biochemistry were observed. We conclude that calicivirus infection of young rabbits causes a subclinical disorder characterised by an acute and transient decrease in circulating heterophils, and focal liver damage that is expressed by intralobular infiltration by heterophils, initially, and, later on, by mononuclear cells. Our finding of persistence of increased values of liver transaminases suggests chronicity of the infection in young rabbits. We propose that, although resistant to RHD, young rabbits infected by calicivirus may be long-term carriers of the infectious agent and, thus, become a major source of transmission of the virus. 相似文献
13.
14.
《畜牧与生物技术杂志(英文版)》2017,(3)
Background: Human Cytomegalovirus(HCMV) infections can be found throughout the body, especially in epithelial tissue. Animal model was established by inoculation of HCMV(strain AD-169) or coinoculation with Hepatitis E virus(HEV) into the ligated sacculus rotundus and vermiform appendix in living rabbits. The specimens were collected from animals sacrificed 1 and a half hours after infection.Results: The virus was found to be capable of reproducing in these specimens through RT-PCR and Western-blot.Severe inflammation damage was found in HCMV-infected tissue. The viral protein could be detected in high amounts in the mucosal epithelium and lamina propria by immunohistochemistry and immunofluorescense.Moreover, there are strong positive signals in lymphocytes, macrophages, and lymphoid follicles. Quantitative statistics indicate that lymphocytes among epithlium cells increased significantly in viral infection groups.Conclusions: The results showed that HCMV or HEV + HCMV can efficiently infect in rabbits by vivo ligated intestine loop inoculation. The present study successfully developed an infective model in vivo rabbit ligated intestinal Loop for HCMV pathogenesis study. This rabbit model can be helpful for understanding modulation of the gut immune system with HCMV infection. 相似文献
15.
微生物制剂对幼兔腹泻治疗的研究 总被引：1，自引：0，他引：1
王仲兵 《中国预防兽医学报》2007,29(6):475-479
本实验从健康家兔肠道正常菌群中经分离、鉴定,筛选出3种有益菌种:需氧芽孢杆菌、酵母菌和厌氧乳酸杆菌,经安全试验和药物敏感试验合格后,分别发酵培养,制成复合型微生物制剂再应用到断奶幼兔中,观察对幼兔体重、消耗饲料量、腹泻发生率等的影响,同时应用微生物制剂治疗腹泻兔,观察其治疗效果。实验表明,应用复合微生物制剂增重效果明显,料肉比分别为4.20:1,50日龄和70日龄的成活率分别为96%和90.67%,第50日龄和第70日龄时腹泻率为1.33%和4.67%。使用兔源菌种制成的Ⅰ型微生物制剂能够减少家兔的耗料量,体重明显增加,显著降低料肉比;能够较好地预防幼兔腹泻的发生和降低死亡只数,并且制剂的菌种对大多数抗生素没有抗药性,具有促进生长、减少或杜绝药物污染的优点。 相似文献
16.
Granulomatous enteritis following oral inoculation of newborn rabbits with Mycobacterium paratuberculosis of bovine origin. 
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下载免费PDF全文 To assess the rabbit as a model for the study of paratuberculosis infection, two groups of newborn rabbits were orally inoculated at one to two days of age with Mycobacterium paratuberculosis (ATCC 19698 or field strain 22206) and compared to uninoculated controls. Nine of thirteen rabbits (69%) inoculated with ATCC 19698, and all three rabbits inoculated with 22206, experienced episodes of intermittent diarrhea starting four months after inoculation. Multifocal granulomas containing acid-fast organisms were observed in the sacculus rotundus and vermiform appendix of the cecum in three of nine rabbits (all with diarrhea) that had been inoculated with ATCC 19698. Although M. paratuberculosis was not recovered from inoculated rabbits when fecal cultures were incubated three months in vitro, a slow-growing mycobactin-dependent form of Mycobacterium was recovered from feces and ileal tissue after incubation for 11-15 months. Reduced feed intake, body weight loss and reduced abdominal fat at necropsy, were not observed. Epithelial transport function across the distal ileum in vitro was not altered nine months subsequent to inoculation. Diarrhea and the histological lesions indicate that the rabbit may be a useful model for the study of paratuberculosis infection. 相似文献
17.
Ferreira PG Costa-e-Silva A Oliveira MJ Monteiro E Cunha EM Aguas AP 《Research in veterinary science》2006,80(2):218-225
Calicivirus infection is the major cause of the severe decrease in the stocks of wild and farm rabbits that has occurred worldwide during the last two decades. Adult rabbits (10-weeks-old) were experimentally infected with a calicivirus inoculum that killed all animals by causing rabbit haemorrhagic disease (RHD) within 24-62 h of infection. The rabbits were used to evaluate blood cell numbers and serum biochemistry every 6h, starting 12h after the inoculation of the caliciviruses. No significant changes in blood parameters were observed in most of the rabbits up to 18 h of infection. Severe leukopenia was seen 6h before death of the infected rabbits; both heterophils and lymphocytes contributed to the decrease in circulating white blood cells. Platelets were also severely decreased in number. Marked enhancement in liver enzymes was seen 6-12 h before death of the infected rabbits. There was also evidence both for cholestasis, as expressed by the elevated levels of direct (conjugated) bilirubin, and for hypoglycemia, an alteration that it is likely to contribute for the seizures that rabbits show during the late stages of RHD. Liver ultrastructure of rabbits that died from RHD revealed extensive hepatocyte vacuolization, severe changes in mitochondrial structure, and depletion of glycogen granules. We conclude that: (i) severe leukopenia characterizes the final hours of calicivirus-induced RHD; (ii) hypoglycemia and cholestasis precede death of rabbits from RHD; (iii) the kinetics of liver enzymes allows an accurate prediction of the time of death of rabbits from calicivirus-induced RHD. 相似文献
18.
Attempts to transmit malignant catarrhal fever (MCF) from 16 bovine cases of the 'sheep-associated' form of the disease are described. On two occasions disease was transmitted to bovine calves but transmission to red deer (Cervus elaphus) was not achieved. In addition, MCF was transmitted from one experimentally affected calf to a rabbit and on another occasion directly to rabbits with material from a field case which failed to transmit to a bovine calf or red deer. Subsequently each of these isolates was readily passaged through rabbits and one was also passaged to Syrian hamsters. Tissue from MCF-affected red deer consistently produced disease on inoculation into rabbits and deer but failed to cause disease in bovine calves. Contact infection between red deer occurred once and roe deer (Capreolus capreolus) were also shown to be susceptible to infection by inoculation. Passage of MCF in rabbits with an isolate from red deer failed to produce evidence of further adaptation even after 125 serial passages. Despite the failure to transmit disease from cattle to deer or from deer to cattle it is considered probable that there is only one sheep-associated agent which causes MCF in both species. The reasons for the anomalies in transmission of this form of the disease are discussed. 相似文献
19.
Ferreira PG Costa-E-Silva A Oliveira MJ Monteiro E Aguas AP 《Veterinary immunology and immunopathology》2005,103(3-4):217-221
Calicivirus infection is lethal for adult rabbits, whereas young rabbits (less than 8-weeks-old) are resistant to the same infectious agent. The virus replicates in the liver and causes a fulminant hepatitis in adult rabbits leading to rabbit haemorrhagic disease (RHD); this is in contrast with the mild and transient hepatitis observed in infected young rabbits. We have used electron microscopy to compare liver leukocyte infiltrates between young (resistant) and adult (susceptible) rabbits, 36-48 h after inoculation of the animals with caliciviruses. In adult rabbits, liver infiltrates were made up mostly of heterophils, and they were located near hepatocytes showing severe cellular damage. In contrast, liver leukocyte infiltrates of RHD-resistant young rabbits were dominated by lymphocytes that depicted membrane contacts with the cell surface of undamaged hepatocytes. We conclude that: (i) the cellular inflammatory response of the liver to calicivirus infection is different in rabbits that are susceptible (adult) or resistant (young) to RHD; (ii) leukocyte infiltration of the adult liver by heterophils is probably directed at the removal of dead hepatocytes, whereas the liver lymphocytic infiltration of young rabbits suggests the expression of viral antigens on the surface of liver cells of the RHD-resistant animals. 相似文献
20.
When monoflora chickens with Lactobacillus acidophilus or Streptococcus faecalis were inoculated with Clostridium perfringens either in broth culture or resuspended in Gifu anaerobic medium broth or supernatant fluid, few or no chickens died. Approximately 50% of germ-free chickens died after inoculation of C. perfringens culture, whereas no conventional birds died after inoculation of broth culture. C. perfringens in the contents of duodenum from germ-free chickens numbered about 10(4) colony-forming units (CFU)/g after inoculation 10(8) CFU broth culture per bird, but in gnotobiotic and conventional chickens this organism decreased or was not detected. When C. perfringens was cultured in intestinal contents collected from germ-free chickens, C. perfringens proliferated but alpha toxin was not detected. These findings indicate that the pathogenicity of C. perfringens was suppressed by L. acidophilus or S. faecalis administered previously or inhibited by normal intestinal flora. 相似文献