a,Full Professor of Environmental engineering and applied Chemistry, Director of Higher National School of Public Works in Yaounde (ENSTP)
bPhD student in Hydrobiology and Environment
cDoctors in Hydrobiology and environmental engineering, Part time lecturers in the department of Animal Biology and Physiology, University of Yaounde 1, Cameroon
d Student of the Higher School of Public Works in Yaounde, specialised in water ressource engineering and management(ENSTP)
e Full Professor of hydrobiology, Environmental engineering and Public health
corresponding email : ajeagahg@yahoo.com
ABSTRACT
In order to evaluate the biodiversity of the forms of dissemination of Sarcocystis in the aquatic medium in Yaounde, a study was carried out from January to June 2016. To do so, monthly samplings wer carried out in several points of the Mfoundi stream and in eight marshy areas (Obili, Melen, Mvog-Betsi, Etoug-Ebé, Mokolo Elobie, Tsinga, Ekounou and Nsimeyong). The physico-chemical analyses were done following standard methods and revealed waters with high temperatures (26.61±0.96 ± 0.08 UC), low oxygenation (21.19 ±4, 52%), average mineralization (566.16 ± 182.31µs/cm), rich in suspended matter (23.37 ±06.52 mg/L) and organic matter. On the other hand, biological analyses were made by the observations of oocysts and sporocysts of Sarcocystis spp. using the Olympus brand inverted microscope at the 40x objectives. These observations followed the concentration and coloration of the organisms in the water samples following the Ziehl-Neelsen technique. The results show the presence of 99 oocytsts and sporocysts of Sarcocystis spp. in the Mfoundi stream and 1753 oocysts and sporocysts of Sarcocystis spp. in the marshy areas. Overall, the highest oocysts and sporocyst densities were recorded during the long dry season in the Mfoundi stream and during the short rainy season in the marshy areas. The abundance dynamics of these enteropathogens are significantly and positively correlated with suspended electric conductivity and organic matter (p <0.05). This contamination of water by enteropathogenic protozoa compromises their use as it would constitute a health risk for the populations using these points.
Key words: Dynamics, Sarcocystis, oocysts, sporocysts, physico-chemistry, aquatic me