Population growth of herbivorous rotifers and their predator (Asplanchna) on urban wastewaters
Por:
Sarma S.S.S., Trujillo-Hernández H.E., Nandini S.
Publicada:
1 ene 2003
Resumen:
We studied the population growth of three Brachionus species (B. calyciflorus, B. patulus and B. rubens) using domestic (Mexico City) wastewater at different phases of treatment (treated: type C, partially treated: type B and crude: type A). We also evaluated growth characteristics of a predatory rotifer (Asplanchna sieboldi) fed B. rubens raised on wastewater and compared the growth rates of animals fed cultured algae. All the three tested brachionid species grew well in controls (i.e. fed on the alga Chlorella). However, populations of B. calyciflorus and B. patulus did not grow on the fully treated wastewater (type C). All three brachionid species grew poorly on partially treated wastewater (type B). In crude wastewater, B. rubens reached densities as high as 200 ind. ml-1. Regardless of Brachionus species, the rates of population increase per day (r) varied between 0.29 and 0.4 in the controls. B. rubens in crude wastewater experienced steep mortality in the first two days but stabilized thereafter. It had generation times, which varied from 3 to 5 days depending on the treatment. Prey (B. rubens) raised on wastewater supported better population growth of A. sieboldi, the highest being from crude wastes. The growth rate of A. sieboldi fed B. rubens, raised on crude wastewater, was the highest (? 0.8 d-1). Thus, the present study showed that culturing of certain species of brachionid rotifers on crude wastewater or partially treated is feasible without addition of alga.
Filiaciones:
Sarma S.S.S.:
Div. of Res. and Postgrad. Studies, Natl. Autonomous Univ. of Mexico, Campus Iztacala, Av. de los Barrios s/n, Los Reyes, Tlalnepantla, State of Mexico, Mexico
Trujillo-Hernández H.E.:
Div. of Res. and Postgrad. Studies, Natl. Autonomous Univ. of Mexico, Campus Iztacala, Av. de los Barrios s/n, Los Reyes, Tlalnepantla, State of Mexico, Mexico
Nandini S.:
Div. of Res. and Postgrad. Studies, Natl. Autonomous Univ. of Mexico, Campus Iztacala, Av. de los Barrios s/n, Los Reyes, Tlalnepantla, State of Mexico, Mexico
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