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Summary Randomised groups of seronegative foals and of adult horses of various origins were inoculated at different intervals with booster injections according to a factorial design. The response curves of HI and SN antibodies were studied over the 12 monthperiod following the first injection. In the light of the results the following vaccination schedules are proposed to meet epidemiological, sport and other requirements. For seronegative foals: booster injections 2 months after the primary vaccination; For ordinary adult horses: booster injections 15 days or 4 months after the primary vaccination. Zusammenfassung Untersuchung verschiedener Pferdeinfluenza-Vaccinationsprogramme in seronegativen Fohlen und Pferden Gruppen seronegativer Fohlen und erwachsener Pferde verschiedener Herkunft wurden in unterschiedlichen Abstanden mit Pferdeinfluenzavaccine geimpft. Uber einen Zeitraum von 12 Monaten nach der Erstinjektion wurde die Bildung hamagglutinationshemmender und serumneutralisierender Antikorper verfolgt. Auf Grund der hierbei erhaltenen Ergebnisse wird das folgende Influenza-Vaccinationsprogramm vorgeschlagen, das den epidemiologischen Forderungen entspricht und den jeweiligen Einsatz der Pferde z. B. im Sportbetrieb weitestgehend berucksichtigt. Bei seronegativen Fohlen soll die Boosterimpfung 2 Monate nach der Primovaccination durchgefuhrt werden und bei erwachsenen Pferden 15 Tage oder 4 Monate nach der Primovaccination. Resume Etude de differents calendriers de vaccination antigrippe equine pour des poulains seronegatifs et pour des chevaux tout-venant Selon un plan experimental factoriel, des groupes de poulains seronegatifs et des chevaux tout-venant randomises ont ete vaccines selon des rythmes differents de rappel. La cinetique des anticorps IHA et SN ete controlee durant les 12 mois suivant la premiere vaccination. A la lumiere de ces resultats, un calendrier vaccinal peut etre propose en fonction des conditions epizootologiques ou sportives. Pour les poulains seronegatifs: vaccination de rappel 2 mois apres primovaccination. Pour les chevaux tout-venant: vaccination de rappel 15 jours ou 4 mois apres primo-vaccination. Resumen Estudio de diversos programas de vacunacion contra la influenza equina en potros sueronegativos y caballos de origen diferente Segun un plan experimental factorial, grupos de potros sueronegativos y caballos de origen diferente randomisados fueron vacunados en intervalos variables de vacunacion de recuerdo. La cinetica de los anticuerpos inhibidores de la hemoaglutinacion y sero-neutralizantes fue comprobada durante doce meses despues de la primo-vacunacion. De acuerdo con los resultados, se puede proponer un calendario de vacunacion teniendo en cuenta las condiciones apizootologicas o deportivas. Para potros sueronegativos: vacunacion de recuerdo dos meses despues de la primo-vacunacion. Para caballos adultos: vacunacion de recuerdo quince dias o 4 meses despues de la primo-vacunacion.

Subunit pseudorabies vaccines that contained only purified glycoproteins of either of 2 strains of pseudorabies virus (PRV) were prepared and subsequently tested for safety and efficacy. The strains of virus used for vaccine production differed in at least 2 properties. One strain (Kojnok) was virulent for pigs and was believed to code for the entire complement of viral glycoproteins. The other (Kaplan) was a deletion mutant that was unable to code for structural viral glycoproteins gI and gp63. Purified glycoproteins were dispersed in an oil-in-water emulsion and were administered IM to pigs. Both vaccines were found to be safe and effective immunogens. Neither caused any local or general reactions, as verified by examination of the injection site (local safety) and by vaccination of pregnant sows in PRV-infected and noninfected herds. Sows vaccinated with the gI+ or gI- vaccine protected their pigs at levels of 93 and 92%, respectively, against a severe challenge exposure that killed 98% of pigs born from nonvaccinated sows. Vaccinated pigs were tested for active immunity by intranasal challenge exposure with the NIA 3 strain. Protection was quantitated by measuring the relative daily weight difference, expressed in percent per day, between vaccinated and control pigs during the first week after challenge exposure (delta G7); the estimated differences were 2.25 and 2.13% for gI+ and gI- vaccines, respectively. The absence of gI and gp63 did not affect the efficacy of this type of subunit glycoprotein vaccines.(ABSTRACT TRUNCATED AT 250 WORDS)

A criterion for the potency testing of pseudorabies vaccine based on the difference between the mean weight gain during the seven days after pathogenic challenge of vaccinated or control piglets is proposed. This criterion, termed ▴G7, has been studied as a function of initial weight variation of the animals, different challenge strains and the period between challenge and the end of the test. The statistical analysis of results optimizes the experimental parameters and gives rise to a quantitative test which discriminates between vaccinates and controls and substantiates a proposal for a minimum vaccine potency requirement. The implementation of the method proposed is compatible with current practice in control laboratories.

In order to investigate the serological interrelationship of the feline picornaviruses a biomathematical system has been proposed based on that already used for foot-and-mouth viruses. Eight strains of virus isolated in America and seven strains from France were compared. It was shown by serology that no strains had dominance and that the organ from which they were isolated had no influence on their classification. On the other hand, it was possible to distinguish the strains by means of the biomathematical system.

Michel Claude, Terré Jean, Soulebot J. P., Chappuis G., Stellmann C., Desmettre Ph. Vaccinations associées du Chien. Comparaison entre vaccinations successives et vaccinations simultanées. In: Bulletin de l'Académie Vétérinaire de France tome 124 n°6, 1971. pp. 277-284.

After vaccination of chickens, rabbits, foals and horses, HI and SN antibody dose response curves were compared for A/Equi 1/Prague and A/Equi 2/Paris strains. The two curves are parallel for a given strain and the relationship of HI and SN titres is constant, whatever the animal species. The distribution of HI and SN titres varies for the two strains. This variation, which is independent of animal species, may be related to the number of sites necessary for the antigenic-antibody response in vitro . It is suggested that the testing of equine influenza vaccine be carried out in the chicken in the light of these results.

The proposed system makes it possible to calculate the bilateral relationship expressed as logR and the dominance expressed as logD for an unknown strain in relation to reference sera, without the help of the serum homologous to the unknown strain.

Pigoury Lucien, Ghabassol C., Stellmann C. Technique sensible de détection dans l’eau de la toxine botulique C, précipitée par le Méthanol. In: Bulletin de l'Académie Vétérinaire de France tome 118 n°8, 1965. pp. 319-323.

Titration of foot-and-mouth disease and Poliomyelitis viruses on pig and monkey kidney cells have been analysed by means of the single-particle (Poisson distribution) and the pharmacology (Gauss distribution) hypothesis. These titrations, carried out on a large number of cell culture tubes, have shown: that the dosage-effect relationship for the cytopathogenic effect of the virus is a Poisson distribution; that the Poisson distribution can be disturbed by some factors such as pipetting errors and aggregation of virus particles in the fluids.

Nine strains of foot-and-mouth disease virus type "O" received in our laboratories since 1971 have been studied serologically by Osler's quantitative method of complement fixation (50% hemolysis). The results, submitted to the biomathematical system of bidimensional classification, allow to conclude that at present in Europe there are two groups of foot-and-mouth disease strains of type "O"; one has reference to our vaccinal strain "O Lausanne 1965" and the other to "O Romania 1972" strain, which has certain points of similarity with subtype "O2". In addition, strain "O Hungary 1975" has been studied on bovines; the immunological tests confirm the serological test.

Medical and sanitary prevention of a growing number of major infectious diseases of bovines has led IFFA-Mérieux to investigate the association of vaccines and to define methods of utilization. Care has been taken to limit the number of interventions and at the same time to retain in the combined valences the efficacy they had when in a state of single constituent. The work which has been carried out for the last ten years, including the study of adjuvants as well as of incompatibility of associations, has permitted the improvement of formulas, reduced in volume (5 ml for a plurivalent dose), in aqueous excipient (aluminum hydroxide and saponin) or oily excipient (oil in water type). These formulas combine 3 foot-and-mouth disease valences with a rabies valence (fixed strain grown on cell culture) or with a brucellosis valence (strain B. abortus MacEwen 45/20 and B. melitensis H 38). The innocuity of these associations allows them to be used in sanitary compaigns; their efficacy is equal to that of monovalent vaccines. A logical vaccination calendar is proposed.

Two methods of evaluating the activity of the foot-and-mouth disease vaccine are compared, leading to the evaluation of the number of protective doses 50% or potency. These methods differ in sensitivity, precision and equivalence potency-percentage of protection. For the same vaccine the value of the PD50 is always larger than that of Pb. We chose the Pb method using a diluent containing no adjuvant. Standards based on the evaluation of average potency have not been taken into consideration; only those standards based on the evaluation of minimum potency ensure respect of OIE's recommendation. This recommendation: 70% minimum potency with 0.95 probability is not an easier alternative, since the average protection observed corresponds in fact to at least 90% taking into account the biological variability of bovines.

The B 19 brucellosis strain has been widely used in the production of live vaccine against Bovine Brucellosis in the field for the last 30 years. Many attempts have been made to stabilize this vaccine but it remains a problem for laboratories which prepare this vaccine. In order to improve our knowledge of the influence of residual moisture and the nature of the conditioning atomosphere, several batches of vaccine were prepared in the same freeze-drying apparatus, either with a different atmosphere, or with a different level of residual moisture. After freeze-drying, the percentage of live bacteria and the stability of the vaccine at 37 degrees and 4 degrees C were investigated. It is thus possible to determine under specific conditions the level of residual moisture which gives: a) the best stability and b) the correct percentage of live bacteria after freeze-drying. Furthermore, by using nitrogen, argon, or a vacuum in the freeze-drying procedure, it was possible to select the most favourable atmosphere for conditioning the vaccine.

The activity of the antibrucellic vaccines was tested on mice by vaccination at varying doses. The vaccinated mice and the controls were then challenged with a fixed quantity of virulent brucella. The animals were then sacrificed, the spleens were weighed and a count was taken of the virulent brucella which they contained. These two indications, weight of the spleen and intensity of infection, allow to compare the activity of the vaccines and to have an indispensible routine test for production control.

Many thousands of people in France and abroad have already benefited from preventive rabies vaccination by means of a vaccine obtained from culture on human diploid cells, perfected ten years ago by R. Lang, the Institut Mérieux and the Wistar Institute. In addition to being well tolerated, the serological efficacy of this vaccine is such that 100% of the vaccines observed had a seroconversion after only two injections at an interval of one month. However, a booster dose should be given 6 to 12 months after the first injection, and a further booster 3 to 5 years later or on request in case of known contamination. These boosters, combined with an anti-tetanus booster, induce such high antibody titers--between 10-100 and even 1000 I.U./ml--that it is easy to obtain substantial batches of combined anti-rabies and anti-tetanus immunoglobulin from a small number of volunteers. The complete efficacy of this new vaccine reduces the number of systematic post-vaccinal serologic controls and its innocuity is such that an extended preventive vaccination programme may be carried out, for instance in the case of children living in areas known to be dangerous.

The bilateral comparison between foot-and-mouth disease virus strains can be made with the help of a simple biomathematical system, showing bilateral relationships and dominances between strains and fixing error limits for these relations, in order to obtain: first a systematic classification (taxonomic aim) and secondly, if necessary, to guide the choice of vaccinal strains (prophylactic aim).