Eficacia de diversas pruebas serológicas para el diagnóstico de la brucelosis porcina

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Endogenous opioids inhibitor (Naloxone), action given it during the lactation, over the rat reproductive activity

Se estudia la acción de Naloxone, administrado siguiendo dos pautas distintas, sobre diversos parámetros reproductivos en la rata: producción láctea (basada en el peso corporal de las crías en el momento del destete), características ováricas (número de cuerpos lúteos y folículos) y niveles sericos de Progesterona en el destete. Asimismo se realza un estudio de las estructuras ováricas de las crías. No se observaron diferencias significativas en cuanto a la producción láctea o al número de Cuerpos lúteos en relación al grupo-control. La concentración sérica de progesterona fue significativamente superior en los grupos de hembras tratadas con naloxone. El número de folículos fue más alto en el grupo de control. Los ovarios de las crías presentaron una actividad menor en el grupo control.Given it following two different patterns, Naloxone action is studied over several reproduction parameters in the rat:milk production (based on offspring body weight al the weaning moment), ovarian characteristics (number of corpus luteum and follicles) and Progesterone serum levels in the weaning. Likewis a litter ovarian structures study is made. Significant differences in respect to milk production or to number Corpus luteum in relation to the control group were's noticed. Progesterone levels were significantly highter in those female groups treated with Naloxone. The number of follicle a highter in the control group. Offsprin ovries showed lower activity in the group ocntrol

Brucella ceti infection in dolphins from the Western Mediterranean sea

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A Brucella melitensis H38ΔwbkF rough mutant protects against Brucella ovis in rams

Brucella melitensis and Brucella ovis are gram-negative pathogens of sheep that cause severe economic losses and, although B. ovis is non-zoonotic, B. melitensis is the main cause of human brucellosis. B. melitensis carries a smooth (S) lipopolysaccharide (LPS) with an N-formyl-perosamine O-polysaccharide (O-PS) that is absent in the rough LPS of B. ovis. Their control and eradication require vaccination, but B. melitensis Rev 1, the only vaccine available, triggers anti-O-PS antibodies that interfere in the S-brucellae serodiagnosis. Since eradication and serological surveillance of the zoonotic species are priorities, Rev 1 is banned once B. melitensis is eradicated or where it never existed, hampering B. ovis control and eradication. To develop a B. ovis specific vaccine, we investigated three Brucella live vaccine candidates lacking N-formyl-perosamine O-PS: Bov::CAΔwadB (CO2-independent B. ovis with truncated LPS core oligosaccharide); Rev1::wbdRΔwbkC (carrying N-acetylated O-PS); and H38ΔwbkF (B. melitensis rough mutant with intact LPS core). After confirming their attenuation and protection against B. ovis in mice, were tested in rams for efficacy. H38ΔwbkF yielded similar protection to Rev 1 against B. ovis but Bov::CAΔwadB and Rev1::wbdRΔwbkC conferred no or poor protection, respectively. All H38ΔwbkF vaccinated rams developed a protracted antibody response in ELISA and immunoprecipitation B. ovis diagnostic tests. In contrast, all remained negative in Rose Bengal and complement fixation tests used routinely for B. melitensis diagnosis, though some became positive in S-LPS ELISA owing to LPS core epitope reactivity. Thus, H38ΔwbkF is an interesting candidate for the immunoprophylaxis of B. ovis in B. melitensis-free areas.Publishe

Spatial distribution and risk factors of Brucellosis

Background: The role of wildlife as a brucellosis reservoir for humans and domestic livestock remains to be properly established. The aim of this work was to determine the aetiology, apparent prevalence, spatial distribution and risk factors for brucellosis transmission in several Iberian wild ungulates. Methods: A multi-species indirect immunosorbent assay (iELISA) using Brucella S-LPS antigen was developed. In several regions having brucellosis in livestock, individual serum samples were taken between 1999 and 2009 from 2,579 wild bovids, 6,448 wild cervids and4,454 Eurasian wild boar (Sus scrofa), and tested to assess brucellosis apparent prevalence. Strains isolated from wild boar were characterized to identify the presence of markers shared with the strains isolated from domestic pigs. Results: Mean apparent prevalence below 0.5% was identified in chamois (Rupicapra pyrenaica), Iberian wild goat (Capra pyrenaica), and red deer (Cervus elaphus). Roe deer (Capreolus capreolus), fallow deer (Dama dama), mouflon (Ovis aries) and Barbary sheep (Ammotragus lervia) tested were seronegative. Only one red deer and one Iberian wild goat resulted positive in culture, isolating B. abortus biovar 1 and B. melitensis biovar 1, respectively. Apparent prevalence in wild boar ranged from 25% to 46% in the different regions studied, with the highest figures detected in South-Central Spain. The probability of wild boar being positive in the iELISA was also affected by age, age-by-sex interaction, sampling month, and the density of outdoor domestic pigs. A total of 104 bacterial isolates were obtained from wild boar, being all identified as B. suis biovar 2. DNA polymorphisms were similar to those found in domestic pigs. Conclusions: In conclusion, brucellosis in wild boar is widespread in the Iberian Peninsula, thus representing an important threat for domestic pigs. By contrast, wild ruminants were not identified as a significant brucellosis reservoir for livestock

Efficacy of oxytetracycline and gentamicin against Brucella suis infection in pigs

Eighteen aborted sows naturally infected with B. suis biovar. 2 were allotted in two groups each of 9 animals. All sows were treated with oxytetracycline given in feed (20 mg/Kg BW daily) during 45 days after abortion, and the half of animals received a combined intramuscular treatment with gentamicin (4 g/day) during the last 15 days of treatment. Ten days after treatment, sows were slaughtered and several lymph nodes, uterus and spleen submitted to bacteriological studies. All animals treated with oxytetracycline alone were found infected in one or more necropsy samples. By contrast, 100% of the animals receiving the combined treatment with gentamicin were fully cured from infection. In conclusion, monotherapy with oxytetracycline is not effective enough against B. suis biovar. 2 infection in sows, while combining this treatment regime with gentamicin during 15 days is fully effective against infection