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چکیده
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This study was carried out with the aim of estimating the effects of different culture temperatures on life-table parameters of two native rotifers, Brachionus plicatilis (B. pli) and B. rotundiformis from Iran. Each of the rotifer species were cultured at three temperatures of 10, 15 and 30ºC. The other environmental conditions were constant and the same for all the treatments, that is, salinity was 15ppt, rotifer density was 500 ind./ml and feeding was by same concentration of marine Chlorella vulgaris. The estimated parameters comprised the ratio of unegged females (UF) to egged females (EF), number of mictic females (MF), number of mictic eggs (ME), number of males (M), number of resting eggs (RE) and number of parthenogenetic eggs (PE) all per mL. of culture medium. Maximum average UF/EF, average MF and average ME was for rotifer pli at 30ºC. The highest mean number of male rotifers was for B. rot produced at 30ºC and maximum number of PE was for B. rot at 10ºC. ANOVA showed differences in the values of the estimated parameters among the treatments (P<0.05), except for the number of RE. A Duncan test demonstrated that difference in UF/EF ratio was only significant between B. rot at 10ºC and B. pli at 30ºC, and between the latter treatment and B. pli at 10ºC. For MF, ME and M, there were significant differences among the treatments of same species at different temperatures and between two species. The difference in the number of PE was not significant among rotifers of same species, and number of RE was not different among all 6 treatments. Temperature had notable influence on most of the measured criteria in the studied rotifers, and both the rotifers grew better at 10 ºC.
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