Hatching and nutritional quality of Artemia cysts progressively deteriorates as a function of increased exposure to hydration/dehydration cycles

Abstract

Nauplii hatching from Artemia cysts are crucial in larviculture nutrition. Artemia cysts may be exposed to repeated hydration/dehydration (H/D) cycles pre-harvesting or during processing and storage. To observe the effect of these cycles on cyst quality, Artemia franciscana cysts were exposed to a comprehensive set of various H/D treatments, differing in the number of cycles (1, 2, or 3) and the duration of the freshwater hydration period (2 or 4 h). Cyst quality was assessed using the criteria of immediate relevance for aquaculture use, such as hatching percentage directly after H/D treatment and after -18°C storage up to 1 month, longevity of axenically hatched starved nauplii, cyst and naupliar energy content, and (for the most extreme H/D treatment) cyst and naupliar fatty acid and vitamin C content. Repeated H/D cycles resulted in significantly (P \ 0.05) decreased cyst hatching, reduced starved naupliar longevity and individual energy content, loss in vitamin C and fatty acid content, and moreover a close correlation between these parameters as a function of progressive H/D treatments. This is of immediate relevance for aquaculture nutrition, as commercial Artemia cysts may have gone through an unknown sequence of H/D cycles in nature or in the processing line, which affects the nutritional quality of the nauplii used in larviculture operations.

The potential of highly nutritious frozen stages of Tyrophagus putrescentiae as a supplemental food source for the predatory mite Amblyseius swirskii

“…For example, high variation in temperature and relative humidity had adverse effects on hydration of decapsulated brine shrimp cysts (Artemia spp.) (Artefeed) and decreased their suitability as food for A. swirskii; subsequently this reduced establishment of the predatory mite (El-Magsodi, Bossier, Sorgeloos, & van Stappen, 2014;. Secondly, the delayed juvenile developmental time of A. swirskii feeding on the frozen diet would ultimately lead to slower population growth in the greenhouse.…”

Which waters hydrate best? A study using brine-shrimp cysts (Artemia franciscana)

“…The lag period was found to be 10 h in the study by El-Magsodi et al, which is slightly shorter than our results. (El-Magsodi et al 2014) However, it is highly possible that there may be some live brine shrimp at 10 h since a number of live brine shrimp were observed at 12 h in our experiments. Overall, it is apparent from these results that the major effect of temperature was on lag period rather than maximum CHNs.…”

“…Brine shrimp have been considered useful organisms for studies on hydration/dehydration. Previous research has explored the kinetics of hydration/dehydration in those specimens and the impacts of successive hydration/dehydration cycles (Morris 1971, El-Magsodi et al 2016, El-Magsodi et al 2014, Wang et al 2010). These reports encouraged us to employ brine shrimp to study the impacts of different types of water on hydration.…”

Hydration/dehydration cycles imposed on Artemia cysts influence the tolerance limit of nauplii against abiotic and biotic stressors

“…However, the stress tolerance was negatively affected by exposure to three H/D cycles. The decrease as a result of multiple H/D cycles was more prominent when a hydration period of 4 h was used, as compared to hydration of 2 h. This result suggests that irrespective of its other documented effects (see El-Magsodi et al 2014), H/D treatment can interact with the induction of thermotolerance and the upregulation of Hsps. In fact a short period of hydration/dehydration exposure of cysts does not seem to cause a deleterious effect on the emerged nauplii of both strains.…”

“…To a certain extent, some level of hydration/dehydration exposure is an almost unavoidable element in the history of any commercial cyst sample from preharvesting until marketing. In our previous study in which cysts went through several hydration/dehydration cycles, the latter factor was shown to have a marked negative impact on the energy content of the embryo, resulting in the hatching of inferior quality nauplii (i.e., decreased cyst hatching, reduced starved naupliar longevity, loss in vitamin C and fatty acid content) (El-Magsodi et al 2014). In the present study, we aimed at investigating the effects of hydration/dehydration cycles of Artemia cysts on the stress responses of cysts and emerged nauplii.…”