A novel polyomavirus (goose hemorrhagic polyomavirus) is the agent of hemorrhagic nephritis enteritis of geese.

We have identified the etiological agent of hemorrhagic nephritis enteritis of geese (HNEG), a fatal disease of European geese. HNEG has been recognized in almost all goose breeding areas, with an epizootic pattern, and up to now, the infectious agent has remained unknown. In order to identify the causative agent, infected tissues from HNEG-affected geese were inoculated to 1-day-old goslings, which then developed clinical signs typical of HNEG. Tissue homogenates from these birds were subjected to Freon extraction followed by sucrose density gradient ultracentrifugation. The resulting main band was examined by electron microscopy and consisted of spherical, naked, papovavirus-like particles approximately 45 nm in diameter. The virus was isolated and propagated in goose kidney cell primary culture. Tissue- or culture-purified virus allowed the experimental reproduction of the disease in goslings. Random PCR amplification of viral nucleic acid produced a 1,175-bp fragment which was shown to be associated with field samples collected from geese affected by HNEG on commercial farms in France. Sequence analysis of the PCR product revealed a unique open reading frame, showing 63 to 72% amino acid similarity with the major capsid protein (VP1) of several polyomaviruses. Finally, based on phylogenetic analysis, we conclude that the causative agent of HNEG is closely related to but clearly distinct from other polyomaviruses; we thus have named this newly identified virus Goose hemorrhagic polyomavirus.

Serologic evidence for bovine immunodeficiency virus infection in France.

We report herein on the first serologic detection of antibodies to bovine immunodeficiency virus (BIV) in France. Serum samples from dairy and beef cattle from southwestern and western France (Landes and Vendée) were tested using a western blot assay with a recombinant 53 kDa gag precursor derived from the Louisiana BIV R29 isolate. We performed our study on the oldest animals from 37 different herds that were under serologic follow up for previous bovine leukemia virus infection. Overall, 398 selected bovine sera were assayed and 15 serum samples from 8 herds reacted with the recombinant 53 kDa BIV R29 gag. Interestingly, reactions obtained with French sera were weaker than with positive Louisiana sera, a finding that may indicate the occurrence of distinct French and Louisiana BIV variants.

A highly virulent togavirus-like agent associated with the fulminating disease of guinea fowl.

During a 1986 natural lethal outbreak of fulminating disease in guinea poult flocks in southwestern France, enveloped virus particles were consistently observed in the gut contents of infected birds. For the present study, a protocol was developed for the purification of these particles. Sucrose-banded virus obtained from birds infected experimentally with virus from the outbreak was found to have a buoyant density of 1.18 g/ml. The purified virus showed hemagglutinating activity, was shown by electron microscopy to have a togavirus-like morphology, and also was shown to be transmissible and pathogenic through oral ingestion. In addition, other enveloped particles have been occasionally detected in gut contents of both infected and uninfected birds; the improbability of the viral nature of these interfering particles is discussed.

Natural mode of horizontal transmission of bovine leukemia virus (BLV): the potential role of tabanids (Tabanus spp.).

In order to evaluate the potential role of hematophagous insects in the natural spreading of bovine leukemia virus (BLV) infection in cattle, a 2-year survey was carried out involving sequential serological tests on 3328 cattle in three different areas. A parallel entomological study was run over the same period, using continuous trapping, in order to determine both the density and variations of horsefly (Tabanus spp.) populations in the close vicinity of the herds. After statistical analysis, this space-time study showed that: (1) There is a significant positive geographical correlation between the rate of incidence of BLV infection and the density of the horsefly population. (2) Seasonal variations in the incidence rate exist; the highest rates are generally observed during summer (from July of September), and the lowest during winter, spring and early summer (from November to mid-July). (3) There is a time link between the rate of sero-conversion and the variations in activity of the horsefly population. All these data combined would appear to indicate that tabanids play a considerable role in the spread of BLV under natural conditions.

Isolation of Mycoplasma cloacale from a number of different avian hosts in great Britain and France.

Following the original isolation of Mycoplasma cloacale from a turkey in Great Britain, only one further turkey isolate has been obtained whereas the mycoplasma has been recovered from 2 species of wild ducks in Britain, and from 2 breeds of domestic ducks and from domestic geese in France. A few isolations have also been made from wild and exotic birds but M. cloacale has not been found in chickens.

[A new intracellular protozoon of Salmo gairdneri Richardson, 1836 (teleost fish). Taxonomic affinities]. / Un nouveau Protiste intracellulaire chez Salmo gairdneri Richardson, 1836 (poisson téléostéen). Affinités systématiques.

Macrophages of 1+ rainbow trout are parasitised by an unknown protozoan. An ultrastructural study permits to associate it with the genus Dermocystidium described in many fishes. This protozoan is characterized by a large vacuole of mitochondrial origin and by concentric structured bodies.

Isolation of Mycoplasma gallisepticum from geese.

Two breeding flocks of 2-year-old geese in the Landes region of Southwest France were cultured for mycoplasmas. In one flock of 134 birds Mycoplasma gallisepticum was isolated from three individuals, from a different site in each bird (i.e. oesophagus, trachea, cloaca). M. gallisepticum was also isolated from the semen of one goose in the other flock of 70 birds, but in neither flock could the true incidence be determined because of prolific overgrowth by acholeplasmas in nearly all the samples.

[Diagnosis of enzootic bovine leukosis by the ELISA test of mixed and individual milk]. / Dépistage de la leucose bovine enzootique à l'aide du test ELISA appliqué au lait de mélange et au lait individuel.

The ELISA test was applied to mixed milk from 325 cowsherds of the Landes region of France. From the 88 cowsheds giving a positive or inconclusive response, individual samples of milk were studied by the ELISA test, and individual samples of serum by the agar immunodiffusion test (1734 cows). The same procedure was carried out on 1250 animals in a sample of 49 cowsheds chosen at random from amongst the 237 cowsheds whose mixed milk gave a negative response to the ELISA test. The results confirmed the importance of the ELISA test applied to mixed milks, provided that the samples are studied several times per year, so as to minimize default errors. The study of individual milk allowed the identification of 92 to 94% of the infected animals, with a specificity of 98 to 99%. The systematic and repeated testing of mixed milks by the ELISA test should allow initial detection of infection and supervision of a satisfactory cost-efficiency report in the decontaminated cowsheds.

Enzyme patterns of the organs of the goose. Effects of fattening on liver enzymes.

The distribution of some enzymes in the organs of the goose was investigated: Creatine-kinase was specific for muscles, Glutamate Dehydrogenase for liver and Gamma-Glutamyl Transferase for pancreas and liver. The production of fatty liver induced an important dilution of liver enzymes except for Lactate Dehydrogenase which was only moderately lowered. This latter enzyme is probably one of the most interesting markers of liver disturbances while fattening is occurring.

Studies on mycoplasma infection of laying geese.

Infertile eggs, dead embryos and tissues from laying geese (airsacs, peritoneum, oviduct, ovary, ova) were examined for presence of myco-plasmas. Forty-three of 110 eggs and the birds laying mycoplasma-containing eggs proved to be positive for mycoplasmas. One of the strains was used for experimental infection of laying geese. A reduction in egg production, an increased number of infertile eggs, egg transmission of mycoplasmas and loss of body weight of hatched goslings, were observed due to the mycoplasma infection.

Isolation and pathogenicity of mycoplasmas from geese.

Several mycoplasma isolation trials were performed on infertile goose eggs and goose embryos which died during incubation, as well as on geese of different ages. A total of 43 out of 110 goose eggs proved to be contaminated by mycoplasmas. Upon autopsy of birds which laid positive eggs, lesions were observed in the airsacs. Mycoplasmas could be isolated from their air sacs and oviduct. Four out of 15 strains examined biochemically and serologically with antisera prepared against all known avian mycoplasma species were identified as Acholeplasma laidlawii and A. axanthum, respectively. Two strains proved to be glucose-positive and arginine-negative and 9 were glucose-negative but arginine-positive. Some strains caused 50-80% mortality among embryos inoculated intra-yolk-sac at 12 days. In goslings inoculated at the age of 3 days with these strains, we observed fibrinous airsacculitis and peritonitis. By inoculating laying geese with one of the strains, we demonstrated decreasing egg production, increasing early-embryo mortality and egg transmission of mycoplasmas.

A new technique for taking blood samples from ducks and geese.

A new technique for taking blood samples from ducks and geese is described. The method could possibly be used in other bird species. It presents many advantages for the operator as well as for the birds and it allows repeated blood samples to be taken, if necessary, in large quantities.