9 research outputs found
Eficacia de diversas pruebas serolĂłgicas para el diagnĂłstico de la brucelosis porcina
Publishe
Endogenous opioids inhibitor (Naloxone), action given it during the lactation, over the rat reproductive activity
Se estudia la acciĂłn de Naloxone, administrado siguiendo dos pautas distintas, sobre diversos parĂĄmetros reproductivos en la rata: producciĂłn lĂĄctea (basada en el peso corporal de las crĂas en el momento del destete), caracterĂsticas ovĂĄricas (nĂșmero de cuerpos lĂșteos y folĂculos) y niveles sericos de Progesterona en el destete. Asimismo se realza un estudio de las estructuras ovĂĄricas de las crĂas. No se observaron diferencias significativas en cuanto a la producciĂłn lĂĄctea o al nĂșmero de Cuerpos lĂșteos en relaciĂłn al grupo-control. La concentraciĂłn sĂ©rica de progesterona fue significativamente superior en los grupos de hembras tratadas con naloxone. El nĂșmero de folĂculos fue mĂĄs alto en el grupo de control. Los ovarios de las crĂas 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
Suppression of B. melitensis Rev.1 erythritol catabolism as a strategy to avoid genital tropism to develop a safe brucellosis vaccine
A Brucella melitensis H38ÎwbkF 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::CAÎwadB (CO2-independent B. ovis with truncated LPS core oligosaccharide); Rev1::wbdRÎwbkC (carrying N-acetylated O-PS); and H38ÎwbkF (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. H38ÎwbkF yielded similar protection to Rev 1 against B. ovis but Bov::CAÎwadB and Rev1::wbdRÎwbkC conferred no or poor protection, respectively. All H38ÎwbkF 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, H38ÎwbkF 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