Animal health studies using participatory epidemiology in the Mandrare Valley, Madagascar.

Pastoral herders in Madagascar have limited access to animal health workers and veterinary medicines, and more information on their livestock diseases is needed, so that effective animal health programmes can be implemented. In this study, participatory epidemiology methods were used to gather such information in the Mandrare Valley. These included pair-wise ranking and matrix scoring. Eleven diseases were deemed to be priorities by pair-wise ranking. Matrix scoring and characterisation showed that the informant groups associated many disease syndromes with the same diseases, indicating agreement and understanding of the key diseases. The Malagasy-named syndromes, Soko, Besorko and Mamany lio, which are gastrointestinal parasitism, clostridial disease and babesiosis, respectively, were identified by every informant group. A greater sample size may be needed to characterise the diseases precisely with matrix scoring because, in this study, the matrices' scores had wide confidence intervals.

Scaling with body mass of mitochondrial respiration from the white muscle of three phylogenetically, morphologically and behaviorally disparate teleost fishes.

White muscle (WM) fibers in many fishes often increase in size from <50 µm in juveniles to >250 µm in adults. This leads to increases in intracellular diffusion distances that may impact the scaling with body mass of muscle metabolism. We have previously found similar negative scaling of aerobic capacity (mitochondrial volume density, V(mt)) and the rate of an aerobic process (post-contractile phosphocreatine recovery) in fish WM. In the present study, we examined the scaling with body mass of oxygen consumption rates of isolated mitochondria (VO(2mt)) from WM in three species from different families that vary in morphology and behavior: an active, pelagic species (bluefish, Pomatomus saltatrix), a relatively inactive demersal species (black sea bass, Centropristis striata), and a sedentary, benthic species (southern flounder, Paralichthys lethostigma). In contrast to our prior studies, the measurement of respiration in isolated mitochondria is not influenced by the diffusion of oxygen or metabolites. V(mt) was measured in WM and in high-density isolates used for VO(2mt) measurements. WM V(mt) was significantly higher in the bluefish than in the other two species and VO(2mt) was independent of body mass when expressed per milligram protein or per milliliter mitochondria. The size-independence of VO(2mt) indicates that differences in WM aerobic function result from variation in V(mt) and not to changes in VO(2mt). This is consistent with our prior work that indicated that while diffusion constraints influence mitochondrial distribution, the negative scaling of aerobic processes like post-contractile PCr recovery can largely be attributed to the body size dependence of V(mt).