Experimentally induced epizootic rabbit enteropathy: Clinical, histopathological, ultrastructural, bacteriological and haematological findings

in World Rabbit Science (2007), 15(2, APR-JUN), 91-102

Epizootic rabbit enteropathy is an emerging disease that has appeared in French intensive enclosed rabbit farms since the beginning of 1997. Common clinical signs are mild watery diarrhoea with ... [more ▼]

Epizootic rabbit enteropathy is an emerging disease that has appeared in French intensive enclosed rabbit farms since the beginning of 1997. Common clinical signs are mild watery diarrhoea with considerable distension of the abdomen. At necropsy, a significant dilation of the stomach and small intestine without gross evidence of acute or chronic enteric lesions (inflammation or congestion) was observed. The purpose of this study was to describe the anatomopathologic changes concerning the small intestine and those concerning the blood profile, in experimentally infected rabbits. In a first part of the experiment, thirty animals were inoculated with a reference inoculum and five were kept as controls for clinical signs examination and histopathological study. In a second part, 17 out of the inoculated rabbits and the 5 controls animals were randomly assigned to blood testing. Microscopic lesions were studied in sections from the different parts of the small intestine (duodenum, jejunum and ileum) by light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The histological findings revealed only limited inflammation in inoculated animals. Major villous changes were atrophy, fusion, destruction and loss of epithelial cells. In inoculated rabbits, the congestion and dilation of blood vessels of jejunal lamina propria were significantly higher than in control animals (P<0.005). There was significantly more (P<0.05) apoptosis of cells of the jejunal epithelium in inoculated rabbits than in control animals. Infiltration of polymorphonuclear neutrophiles was observed into the jejunal or ileal tunica muscularis. SEM performed on the intestinal tract of 15 inoculated rabbits revealed blankets and globular particles of mucus associated with numerous bacteria on jejunum and ileum villi. This was; not observed in the intestinal tract of control rabbits. Bacteria were found adhering to the epithelial surface and inside intestinal epithelial cells in a few animals by TEM and by light microscopy after Warthin-Starry staining. None of the bacteria isolated from the intestinal mixed contents and cultivated on usual media, are commonly known as rabbit's pathogens. Regarding the haernatological profile, neutrophil counts significantly increased (P<0.05) and lymphocyte counts significantly decreased (P<0.01), in inoculated rabbits compared to those of the control group. [less ▲]

Infectious agents associated with epizootic rabbit enteropathy: Isolation and attempts to reproduce the syndrome

in Veterinary Journal (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 ... [more ▼]

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. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]

Viral infections in pigeons

in Veterinary Journal (2006), 172(1), 40-51

This review provides a current update on the major viral diseases of the domestic pigeon (Columba livia domestica), based on scientific reports and clinical experience. Paramyxovirus 1, adenovirus ... [more ▼]

This review provides a current update on the major viral diseases of the domestic pigeon (Columba livia domestica), based on scientific reports and clinical experience. Paramyxovirus 1, adenovirus, rotavirus, herpesvirus 1, poxvirus and circovirus infections are described according to common clinical signs and target tissues. Since pigeons are sometimes treated as if they were poultry, the review also summarises the common viral infections of poultry for which pigeons are considered resistant. It is hoped that the review will provide a useful reference for veterinarians and others and offer advice on the diagnosis, treatment and prevention of the major infectious diseases of pigeons. (c) 2005 Elsevier Ltd. All rights reserved. [less ▲]

Enteritis and enterotoxaemia in rabbits

in Duchesnes, C.; Menozzi, M. G.; Pelkonen, S. (Eds.) et al Diagnosis and typing of clostridia in medical and food microbiology (2006)

Beak Trimming

in Veterinary Journal (2005), 170

To trim or not to trim beaks? It is always a good time to raise this difficult question. Indeed, since the release of the Brambell Committee report1 on welfare in the UK in 1965, discussion on the welfare ... [more ▼]

To trim or not to trim beaks? It is always a good time to raise this difficult question. Indeed, since the release of the Brambell Committee report1 on welfare in the UK in 1965, discussion on the welfare of beak-trimmed birds has continued unabated. The aim of this new book (with its 15 contributors) is not, of course, to close the debate but merely to consolidate the huge amount of scientific information available on methods welfare and alternatives to beak-trimming. In the Preface, it is stated that the book will be of interest to welfare groups, policy makers, scientists, industry leaders and students of poultry science who wish to acquaint themselves with the welfare issues associated with beak-trimming and the potential solutions for reducing the need to beak-trim poultry. This goal is achieved to the extent that most of the information (although sometimes rather concisely) is presented in the eight chapters of this 174 page book. The first chapter describes the methods and reasons for beak-trimming. Chapter 2 raises the ethical question of beak-trimming and gives some of the pros and cons of the arguments. Pain and nerve injuries induced by beak-trimming are presented in Chapters 3–5 and the production responses (improved liveability, plumage quality and feed efficiency during egg laying) of beak-trimmed birds are assessed in Chapter 6 with bird health and handling issues associated with beak-trimming in Chapter 7. The last chapter is devoted to alternatives to beak-trimming. It includes environmental enrichment methods; a consideration of the genetics of feather pecking and cannibalism; dietary recommendations to reduce cannibalism in chickens and laying hens; manipulation of light intensities and colour to modify behaviour; management of body weight; application of abrasive strips in the feed trough to blunt the tips of the beaks of laying hens and the use of fitted devices and stock wound spray in injured birds to prevent further pecking. Among all these alternatives, the genetic solution might well prove to be the most sustainable, efficacious and cost effective. Overall, however, throughout the book this reviewer had the feeling, rightly or wrongly, that it was mostly written by opponents of beak-trimming and that arguments of the defence were sometimes omitted. [less ▲]

Risk evaluation of the transmission of the avian influenza virus to humans

in Annales de Médecine Vétérinaire (2004), 148(2), 65-77

Since mid-december 2003, an epizootic of highly pathogenic avian influenza (type A, sub-type H5N1) occurs in eastern and south-eastern Asia. This epizootic is historically unprecedented in its virulence ... [more ▼]

Since mid-december 2003, an epizootic of highly pathogenic avian influenza (type A, sub-type H5N1) occurs in eastern and south-eastern Asia. This epizootic is historically unprecedented in its virulence, geographical spread, and economic consequences for the agricultural sector. Implications for human health were registered in Vietnam and in Thailand. This paper summarizes the current knowledge about the risk evaluation of the transmission of avian influenza virus to humans. The current asian epizootic has highlighted the key role of global health information systems and also the need for exhaustive notification of human and animal cases. It reinforces the concept of veterinary public health. [less ▲]

Examination of Escherichia coli from poultry for selected adhesin genes important in disease caused by mammalian pathogenic E-coli

in Veterinary Microbiology (2002), 84(3), 231-241

A collection of 1601 extraintestinal and intestinal Escherichia coli isolated from chickens, turkeys and ducks. in Belgium, France and Spain, was hybridised with gene probes specific for fimbrial and ... [more ▼]

A collection of 1601 extraintestinal and intestinal Escherichia coli isolated from chickens, turkeys and ducks. in Belgium, France and Spain, was hybridised with gene probes specific for fimbrial and afimbrial adhesins (F17, F18, S (Sfa/F1C), Bfp, Afa, Cs31A, Intimin (Eae), Aida-1) of intestinal, urinary and invasive E. coli of mammals and with a probe specific for the P (Pap/Prs) fimbrial adhesin of urinary and invasive E. coli of mammals and birds. Three hundred and eighty-three strains (23.9%) were P-positive, 76 strains (4.8%) were Afa-positive, 75 strains (4.7%) were F17-positive, 67 strains (4.2%) were S-positive, 23 (1.4%) were Intimin-positive. and all were F18-, Cs31A-, Aidal- and Bfp-negative. The 75 F17-positive strains harboured different major subunit A-encoding gene variants, but the f17Ac variant was the most frequent (52 strains, 69,3%) and seven strains (9.3%) were not typeable. The f17G gene variant coding for the GII adhesin was the most frequent (56 strains, 75.0%), whereas the f17GI gene variant was present in four strains (5%) and 15 strains (20.0%) were not typeable. All Afa-positive strains harboured the afa-8 variant. The 23 Intimin-positive E. coli tested positive for the beta -variant (16 strains; 69.6%) or for the gamma -variant (seven strains;, 30.4%) of the eae gene. Chicken and turkey E. coli were more frequently probe-positive (43.6 and 43.1 %, respectively) than duck E. coli 31.5%) and extraintestinal E. coli were also more frequently probe-positive (48.4%) than intestinal strains (18.5%). Different combinations of probe positive hybridisation results were observed in 72 of the 540 probe-positive E. coli (13.3%). The most frequent combinations were between AfaE-8 and F17 probes (47 strains; 8.7%) and between P and S probes (13 strains. 2.4%). Although f17- and afa-8-related DNA sequences can be plasmid-located in mammalian E. coli. they were not in avian E. coli. Besides the P fimbrial adhesin, F17 and S fimbrial and Afa-VIII and Intimin afimbrial adhesins may thus represent colonisation factors of avian pathogenic E. coli. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

Dominantes pathologiques des pigeons

in Brugère, J.; Picoux (Eds.) Manuel de Pathologie Aviaire (2002)

Duck plague: a permanent threat for domestic and wild anatids

in Annales de Médecine Vétérinaire (2001), 145(5, NOV-DEC), 287-291

Duck plague: a permanent threat for domestic and wild anatids. Duck plague, also named duck virus enteritis is a disease of ducks, geese and swans of all ages. The authors present a review of the current ... [more ▼]

Duck plague: a permanent threat for domestic and wild anatids. Duck plague, also named duck virus enteritis is a disease of ducks, geese and swans of all ages. The authors present a review of the current knowledge about this viral infection. [less ▲]

Study of the Virulence of Five Strains of Amyxomatous Myxoma Virus in Crossbred New Zealand White/Californian Conventional Rabbits, with Evidence of Long-Term Testicular Infection in Recovered Animals

in Journal of Comparative Pathology (2000), 122(2-3, Feb-Apr), 101-13

The virulence of five amyxomatous myxoma virus (MV) strains, the clinical and pathogenetic effects of which had been studied previously in specific pathogen-free (SPF) rabbits, was determined by ... [more ▼]

The virulence of five amyxomatous myxoma virus (MV) strains, the clinical and pathogenetic effects of which had been studied previously in specific pathogen-free (SPF) rabbits, was determined by inoculation of five groups of 10 crossbred New Zealand White/Californian conventional rabbits. A much more acute myxomatosis syndrome was produced in conventional rabbits than that reproduced previously in SPF animals. However, the main clinical signs were of the respiratory type. The MV strains MYX 254/95 and 801 appeared very virulent, killing all the inoculated animals. The strains MYX 217/95, MYX 555/94 and Saint Benoist were somewhat attenuated, killing only seven, six and six rabbits, respectively. Extensive lung lesions due to supervening bacterial infections were observed in 36 of the 39 rabbits that died. Lethality was found to be a better estimate of virulence than mean survival time. By 98 days after viral inoculation, all the surviving animals had completely recovered. At that time, they were immunosuppressed by treatment with adrenocorticotrophic hormone (ACTH) for 10 days to determine whether they still harboured the virus. After the ACTH treatment, eight of the 11 surviving rabbits showed clinical signs that resembled amyxomatous myxomatosis. All the virological examinations performed on naso-conjunctival exudate, on mononuclear cells, on eyelids and on ovaries remained negative but infectious virus was isolated from the testes of three of six surviving male rabbits. [less ▲]