Morphometric and demographic responses of brachionid prey (Brachionus calyciflorus Pallas and Plationus macracanthus (Daday)) in the presence of different densities of the preda
Por:
Sarma, SSS, Resendiz, RAL, Nandini, S
Publicada:
1 mar 2011
Categoría:
Aquatic Science
Resumen:
We quantified the indirect effects of different densities (1, 4, 16 individuals per jar) of the predator Asplanchna brightwellii on the morphometry and demography of their prey Brachionus calyciflorus and Plationus macracanthus. Population growth and life table demography experiments were separately conducted for each of the two prey rotifer species while keeping A. brightwellii in indirect contact. The brachionids were fed the green alga Chlorella vulgaris at a density of 1 x 10(6) cells ml(-1). As compared to those cultured in the absence of the predator, in the presence of A. brightwellii the postero-lateral spines of P. macracanthus increased by about 15 mu m, while in B. calyciflorus the increase was more (> 80 mu m). For both the brachionid species, the peak population density significantly decreased in the presence of A. brightwellii. The reproductive variables viz., net reproductive rate, generation time, and the rate of population increase of B. calyciflorus and P. macracanthu
Filiaciones:
Sarma, SSS:
Univ Nacl Autonoma Mexico, Lab Zool Acuat, Div Invest & Posgrad, Tlalnepantla 54090, Edo De Mexico, Mexico
Resendiz, RAL:
Univ Nacl Autonoma Mexico, Lab Zool Acuat, Div Invest & Posgrad, Tlalnepantla 54090, Edo De Mexico, Mexico
Nandini, S:
Univ Nacl Autonoma Mexico, Lab Zool Acuat, Div Invest & Posgrad, Tlalnepantla 54090, Edo De Mexico, Mexico
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