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The complement fixation and gel diffusion tests for Brucella ovis ram epididymitis were compared with an indirect ELISA using antigens from B ovis extracted in hot saline, rough B ovis lipopolysaccharide or a cytosolic fraction of rough B melitensis 115, and commercial anti-IgG (heavy and light chain specificity) or protein G conjugates. None of the antigens and conjugates used in the ELISA gave better results in terms of sensitivity and specificity than the complement fixation or the gel diffusion tests with the sera of 41 rams naturally infected with B ovis, 17 rams inoculated conjunctivally with B ovis and 53 Brucella-free rams. The protein G conjugate significantly reduced the background reactivity of the sera from the Brucella-free rams but did not improve the sensitivity of the ELISA with the anti-IgG conjugate.

When a pathogen infects a number of different hosts, the process of determining the relative importance of each host species to the persistence of the pathogen is often complex. Removal of a host species is a potential but rarely possible way of discovering the importance of that species to the dynamics of the disease. This study presents the results of a 12-year programme aimed at controlling brucellosis in cattle, sheep and goats and the cascading impacts on brucellosis in a sympatric population of red deer (Cervus elaphus) in the Boumort National Game Reserve (BNGR; NE Spain). From February 1998 to December 2009, local veterinary agencies tested over 36 180 individual blood samples from cattle, 296 482 from sheep and goats and 1047 from red deer in the study area. All seropositive livestock were removed annually. From 2006 to 2009 brucellosis was not detected in cattle and in 2009 only one of 97 red deer tested was found to be positive. The surveillance and removal of positive domestic animals coincided with a significant decrease in the prevalence of brucellosis in red deer. Our results suggest that red deer may not be able to maintain brucellosis in this region independently of cattle, sheep or goats, and that continued efforts to control disease in livestock may lead to the eventual eradication of brucellosis in red deer in the area.

The effect of chronic alcoholism on neuronal nuclear size and neuronal population of two memory-related diencephalic centres, the mammillary body and the anterior thalamic complex, has been examined in 24 chronic male alcoholics and 22 agematched male controls. Cases were subdivided into three age groups (30-44 years, 45-59 years and 60-75 years). The results showed a significant reduction in both neuronal numbers and nuclear size in alcoholics compared to controls. Differences were especially high in the youngest alcoholics. The intensity of liver damage (steatosis vs. cirrhosis) did not have any sig-nificant effect. Moreover, an age-related decrease of neuronal number and karyometry was seen in controls but not in alcoholics. Our results suggest that chronic alcoholism accelerates the rate of neuronal loss in the mammillary body and anterior thalamic complex to a degree equ ivalent to aging. Likewise, chronic alcoholism impairs the compensatory increase in neuronal nuclei area seen in normal aging in these same structures. Our findings show that medial diencephalic memory centres are damaged in chronic alcoholism, which may contribute to the clinical symptomatology of these persons.