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The discriminatory potency of variable number of tandem repeats (VNTR), based on 7 loci (MIRU 26, 27 and 5 ETRs A, B, C, D, E) was assayed on Mycobacterium bovis strains obtained from samples due to tuberculosis in two slaughterhouses in Algeria. The technique of MIRU-VNTR has been evaluated on 88 strains of M. bovis and one strain of M. caprea and shows 41 different profiles. Results showed that the VNTR were highly discriminatory with an allelic diversity of 0.930 when four loci (ETR A, B, C and MIRU 27) were highly discriminatory (h>0.25) and three loci (ETR D and E MIRU 26) moderately discriminatory (0.11

The major cause of meat rejection at the slaughterhouse of Bobo-Dioulasso is bovine tuberculosis. The objective of this work was to confirm the postmortem diagnosis pronounced at the slaughterhouse using laboratory methods (direct examination following Ziehl-Hielsen staining and isolation of Mycobacterium strains following culture in a Loewenstein-Jensen medium. During the study, 39 pathogenic Mycobacterium strains (38 Mycobacterium bovis and 1 Mycobacterium tuberculosis) out of 100 sampled out suspicious strains, were studied. No Mycobacteria typical of M. farcinogenes was found on direct examination. We were then able to differentiate between bovine tuberculosis and bovine farcy. The results confirm the well-founded decision in the slaughterhouse to discard the meat on the grounds of tuberculosis. The majority of cattle is located in villages around Bobo-Dioulasso and its is therefore highly likely that the disease is enzootic in the area with a fairly high level of infection in animals.

Spongiform encephalopathies, also called prion encephalopathies, are characterized, in human as well as in animals, by (1) their clinical picture which indicates strict localisation in central nervous system, (2) their histological aspect: spongiform degeneration and neuronal loss, and (3) their transmissibility in the same animal species but also from man to animal. The nature of the pathogenic agent is still debated. This agent could be one isoform of the prion protein which, probably because of a modification of its tertiary structure, is partially resistant to proteolytic enzymes. Recent description of a bovine spongiform encephalopathy caused by meat flour absorption has raised again the question of the transmissibility of these animal diseases to human.

Yersinia enterocolitica has been researched in 200 samples of human stools, 40 animals excrements, 38 specimens of soils and 46 of water; the microorganism has been recovered in respectively 3.5%, 10%, 10.5% and 26% out of the total of samples examined; the strains isolated belong to different Wauter's biotype scheme but the biotype 1 is the most predominant except in soil samples. None of biotype 2 and 4, admitted to be adapted to man, has been isolated from human stools. We think that the notion of adaptation of a given biotype to a given host must be reviewed. These data, although they demonstrate the existence of yersinia enterocolitica in Algeria, because of the small number of samples examined, do not reflect exactly the real incidence of the infection caused by this microorganism.

Campylobacter jejuni has been researched in raw milk, skin and excrement of chicken. All milk samples are negatives but 66% of chicken skin and 12% of chicken excrements are positives. An enrichment phase using brucella broth added with horse blood and antibiotics is necessary.

In the first part the authors compare the results of the test effected by means of a buffered antigen (EAT) whose cellular concentration was about 10%, with those of slow seroagglutination (SAW) and complement fixation (FC). Like the complement fixation, the buffered antigen test is more specific than seroagglutination. On the other hand, with such an antigen concentration the test lacks sensitivity. In the second part the authors compare the results obtained by these three tests--but this time utilizing a buffered brucella antigen of cellular concentration of approximately 5%--on bovines and ovines whose infection had been determined bacteriologically. The authors have established, under these conditions, that the buffered brucella antigen test allows the screening of a greater number of infected animals than does the SAW or even the FC. Both for bovines as well as ovines, the agreement between SAW and EAT equals 89%; betueen FC and EAT it reaches 93%; in case of disagreement it is always the EAT which is positive.

Differences in nitrogen and RNA contents were found between liquid-associated and solid-adherent bacteria isolated from the reticulo-rumen of ruminants offered various diets. Consequences on the estimation of the bacterial nitrogen flow to the duodenum are discussed.

The heat-stable enterotoxins produced by strains S126A and 510 of bovine origin have been purified to homogeneity. Their amino acid sequences are identical and correspond to that of the heat stable enterotoxin isolated from porcine origin: Asn-Thr-Phe-Thr-Cys-Cys-Glu-Leu-Cys-Cys-Asn-Pro-Ala-Cys-Ala-Gly-Cys-Tyr.

DNA-DNA colony hybridizations with a ST1a probe were done on bovine enterotoxigenic Escherichia coli strains and compared with the suckling mouse test. The results show that one fourth (7/24) of the strains positive in the baby mouse test do not hybridize the ST1a probe and suggest the existence of another or other toxins among the bovine enterotoxigenic E. coli strains.

Mean duodenal flow of bacterial DM (5130 +/- 358 g/d) represented 60% of total duodenal DM flow in dairy cows fed hay and concentrate (50/50). Contribution of solid-adherent bacteria (SAB) to the total bacteria entering the small intestine amounted to 71%. It must be taken into account in the estimation of the duodenal flow of bacterial compounds.

Listeria monocytogenes releases its antigens during the exponential phase. Electrosyneresis on agarose allows detection of these antigens in the supernatant of broth culture following a 3 h incubation of the strains. This serotyping method seems to be easy, rapid and reproductible. The authors have investigated 83 strains of different origines and find no difference with agglutination. However, during the stationary phase, L. monocytogenes releases other antigens which gave precipitation lines with all commercial sera tested.

The large number of avian strains isolated from pathological samples lead us to use serologic method in order to compare the serotypes of animal and human strains. The results show that the serotypes identified in strains from man (1, 2, 8, 9, 12, 14, 16 and 20) are more numerous than those identified in strains from animals (1, 2, 3, 4 and 8), and that the serotypes 1, 2 and 3 are found in animals more often (98%) than in man (47%). The distribution of the identified serotypes are similar to Piening et al's and Schaefer's but with different proportion, and inverse to Nemoto's and Tsukamura's. The transmission of M. avium from animal to man by the intermediary of the environment is discussed.

The antimicrobial susceptibility of 106 strains of Campylobacter jejuni/coli recovered from animals and humans was studied using broth microdilution panel. Human and animal strains exhibit similar susceptibility, with the exception of the strains from pigs which are more resistant to erythromycin and clindamycin. Among the hippurate negative strains (C. coli), these strains are also recognizable from those recovered from other hosts.

Bovine enteroviruses were first classified into two main groups on a serological basis. The ability to grow in the presence of 5 mug/ml of 2(alpha-hydroxybenzyl)-benzimidazole (HBB) has been reported to be characteristic of the strains belonging to group I. Twenty-six strains isolated in Algeria and previously serologically grouped were submitted to the action of GBB. The viruses of our group I (similar to La Placa's group I) exhibited the same propertie, whereas the strains of our group II were inhibited by GBB as are the strains belonging to La Placa's group II.

The digestive system of the Ophryoscolescides includes different parts : the adoral ciliary zone, the cytostome, the oesophagus, the endoplasm, the rectum and the anus. The endoplasm appears as a digestive sack surrounded by the mesoplasm. This fibrillary envelop separates it from the ectoplasm. It's in the endoplasm that the mechanism of the digestion develops. The endoplasm contains many different structures. It includes macrovesicles of three types, bacteria, plant-particles, microvesicles of two types, ergastoplasm, polysaccharides, the Golgi apparatus and fibrils. The macrovesicles of the first and the second type are not to be found simultaneously in the same endoplasm. The macrovesicles of the third type, very few in number, are different of the previous ones by their double membrane and their denser granulations. Large-sized vesicles contain bacteria at different stadia of digestion. At the end of the digestion, the bacteria are completely or partially degraded. The plant-particles ingested by the Ciliate are to be found in the endoplasm, surrounded by a vesicle. A first type of microvesicles are found in the oesophagus and in the rectum. They are distinguished by a deep black coloration of variable shape. Another type of microvesicles is also present in the endoplasm. They are small bright vesicles that can bud from large-sized vesicles. In the endoplasm the ergastoplasmic lamellae and rings are easily recognizable thanks to the ribosomes, that edge their external membrane. The ribosomes are also situated along the mesoplasm, around polysaccharidic grains and in small groups between the other endoplasmic elements. The polysaccharidic grains are netting-needle shaped bodies. Noirot-Timothee confers them a reserve function. The Golgi apparatus includes eight to eleven saccules. The extremities of those saccules present swellings or golgian ampullae. The endoplasm is also strewn with fibrillary structures that, cross-section are arranged in groups of four or five tubules. This type of endoplasm is found in Ophryoscolescides taken from a ruminant that has been fasting for several hours. In some individuals the endoplasm can have a totally different aspect. It is filled with vesicles of quite different sizes and shapes. The localization test of the acid phosphatase reveals, in this type of endoplasm, lead deposits. These vesicles are probably autophagic vesicles.

A study has been carried out to detect the frequency of atypical mycobacteria in ganglions belonging to two types of animals: bovine and swine. A total of 250 samples (150 cows and 100 pigs) were studied. The samples were decontaminated by the lauryl-sulfate technique, using two mycobacteria culture media: Löwenstein-Jensen and Coletsos base. 14 pig ganglion strains were isolated (8 M. avium; 3 M. gordonae; 2 M. fortuitum; 1 M. chelonei) and 13 from the cow samples (5 M. avium, 3 M. Kansasii; 2 M. gordonae; 2 M. fortuitum; 1 M. phlei). The most frequently isolated mycobacteria was M. avium (48.14% of total isolated strains). This study confirms the possible importance of these animals in the epidemiology of mycobacteriosis.

Two hundred and eight strains of Brucella isolated from cattle and 5 isolated from man in various areas of France, during a two-year period from 1972 to 1974, were examined by all methods recommended by the Subcommittee on Taxonomy of the genus Brucella and were found to have the same characteristics that identify and define the species Brucella abortus. Of the 213 strains, 105 (49,29 p. 100) were biotype I, 103 strains (48,36 p. 100) biotype 3, three strains (1,41 p. 100) biotype 4 and 2 strains (0,94 p. 100) biotype 2. The distribution of Brucella abortus biotypes isolated from cattle and man in France is reviewed and compared with the data from our sample. It corroborates the epidemiologic importance of Brucella abortus biotype 3, just after type 1, and the absence of biotypes 5 to 9(1) in France. Five strains of Brucella abortus biotype 3, originating from a well-defined geographical area, are ureaseless. This new biochemical character distinguishes these strains from the main group of biotype 3 and is discussed from an epidemiological and methodological point of view. Data on the oxydative rates obtained on 12 substrates by the 213 strains are presented in graphic form which reveals a metabolic profile for the species Brucella abortus. The interest of this graphic presentation is discussed and its use should be recommended.