Effects of algal food quality on fecundity and population growth rates of Daphnia

Abstract

1. Food quality was at least as important as food quantity for both fecundity and population growth responses of the cladoceran Daphnia pulicaria fed the green alga Ankistrodesmus falcatus grown under N limitation, P limitation, or non‐limited condition. 2. The fecundity of D. pulicaria was reduced under conditions of low food quality (low N or low P) compared with that for animals fed control non‐limited algae regardless of ration size. The reduced fecundity of D. pulicaria fed P‐limited food could be partially alleviated by increasing the ration (hence, compensation), but such was not the case for animals fed N‐limited food. 3. Population growth rates of D. pulicaria (rmax) were significantly reduced under conditions of low‐quality food for both N‐limited and P‐limited algae. Population growth rates were unaffected by ration size, indicating no compensation.

The influence of algal densities on the toxicity of chromium for Ceriodaphnia dubia Richard (Cladocera, Crustacea)

“…Food quality is at least as important as quantity, for the fecundity, population growth and survival of cladocerans (Kilham et al, 1997). The observed reduction of reproduction of C. dubia might result from a diet quality effect; in other words, metal could have affected the nutritional value of the algal cells to which they were exposed.…”

Impact of algae and their concentrations on the reproduction and longevity of cladocerans

“…This indicates that the microalgae culture medium in our study possessed suitable nutritional quality, at least in the case of S. incrassatulus and P. subcapitata. Quality and quantity of mineral nutrients for algal growth have an effect on the size and biochemical composition of microalgae (Kilham et al 1997), which subsequently influence growth and development of microalga consumers. All the essential macronutrients in the culture medium used for algae production were in no-restraining concentrations, which leads to (10) unrestricted conditions that could have contributed to an increase in the main macromolecules consumed by the filtering organisms.…”

A test of the role of polyunsaturated fatty acids in phytoplankton food quality for Daphnia using liposome supplementation

“…A considerable amount of research has focused on characterizing the importance of phytoplankton food quality for herbivorous zooplankton nutrition (Ahlgren et al 1990;Gulati and DeMott 1997;Kilham et al 1997). These and other studies demonstrate that herbivorous zooplankton growth rates are sometimes strongly correlated with the mineral and biochemical composition of the phytoplankton they consume (Müller-Navarra 1995;Sterner and Schulz 1998).…”

“…Liposome supplementation of a FA mixture, which included a saturated fatty acid and the four 3 PUFAs most prevalent in cryptophytes but rare in cyanophytes, accounted for 59% of Daphnia somatic growthrate differences and 47% of clutch-size differences between the cyanophyte and cryptophyte diets. Our study suggests that phytoplankton 3 PUFA, and especially EPA, content plays an important direct role in herbivorous zooplankton nutrition.A considerable amount of research has focused on characterizing the importance of phytoplankton food quality for herbivorous zooplankton nutrition (Ahlgren et al 1990;Gulati and DeMott 1997;Kilham et al 1997). These and other studies demonstrate that herbivorous zooplankton growth rates are sometimes strongly correlated with the mineral and biochemical composition of the phytoplankton they consume (Müller-Navarra 1995;Sterner and Schulz 1998).…”