Annual dynamics of glycogen, lipids and proteins during the sexual cycle ofPerna perna(Mollusca: Bivalvia) from south-western Morocco

Abstract

Field investigations on Perna perna were carried out in 1999 in an unpolluted site (Cap Ghir) and a wastewater-polluted site (Anza) to determine the contents of glycogen, lipids and proteins in mussel samples collected every month. Sample analyses were made using the entire soft masses of male and female mussels or their gonads only. Compared to unpolluted P. perna, the glycogen and lipid concentrations found in polluted mussels showed significantly quantitative variations throughout the year; in contrast, insignificant differences were only found for protein concentrations. Female gonads contained higher rates of lipids than male ones, whereas protein contents were similar. In contrast, in entire mussels, females were richer than males, whatever the biochemical parameter considered. Apart from protein rates in December, most of highest concentrations were noted from October to November. Contrary to unpolluted mussels (of which storage components were constituted by glycogen and lipids), a different reserve strategy, mainly based on the use of lipids, followed by that of proteins would exist in the P. perna from the polluted bed.

Biochemical composition of New Zealand geoduck clam broodstock (Panopea zelandica ) conditioned under different temperature and feeding regimes

“…The combined results of the present study and the reproductive study by Le et al (2014) indicate that glycogen contents were sufficient to support gonad development in animals across all temperature and feeding regimes, except for those animals exposed to high temperature and low food rations on day 73, as observed by a dramatic decrease in glycogen in flesh samples of these animals. The same trend was found in the male gonad of the mussel Perna perna (Benomar et al 2010) the clam Mactra chinensis (Li et al 2011) and the oysters Crassostrea gigas (Li et al 2000) and C. plicatula (Li et al 2006). This conclusion is supported by the comparable trends in condition and gonadosomatic indices reported for these animals by Le et al (2014).…”

“…Therefore, using all geoducks in this analysis, results showed increased spermatogenesis within treatment individuals compared with those in the initial and reference groups. The same trend was found in the male gonad of the mussel Perna perna (Benomar et al 2010) the clam Mactra chinensis (Li et al 2011) and the oysters Crassostrea gigas (Li et al 2000) and C. plicatula (Li et al 2006). The mechanism for this reproductive process was described by Unuma, Yamamoto, Akiyama, Shiraishi and Ohta (2003) in three urchin species as the use of protein stored in testicular nutritive phagocytes for synthesis of nucleic acids that constitute sperm.…”

“…However, no such differences were observed between groups in flesh samples, except for animals exposed to high temperature and low food ration at day 73. Normally, protein content is expected to increase in the gonads during early gametogenesis and then rapidly decrease as protein contributes to the formation of gametes, especially sperm (Li, Osada & Mori 2000;Li, Liu, Shirasu, Chen & Jiang 2006;Benomar, Costil, El Filali, Mathieu & Moukrim 2010;Li, Yang, Ke & Kong 2011). Similarly, glycogen in the adductor muscle has been shown to provide metabolic energy for the scallop A. irradians concentricus (Barber & Blake 1981).…”

“…Protein contents in flesh samples of geoducks conditioned in different temperature and feeding ration regimes were similar to those of animals in the initial and reference groups, but viscera samples of animals within treatments had slightly lower protein contents than those in the initial and reference groups. Normally, protein content is expected to increase in the gonads during early gametogenesis and then rapidly decrease as protein contributes to the formation of gametes, especially sperm (Li, Osada & Mori ; Li, Liu, Shirasu, Chen & Jiang ; Benomar, Costil, El Filali, Mathieu & Moukrim ; Li, Yang, Ke & Kong ). Thus, the differences in viscera samples are interpreted to reflect the increasing gonadal development of treatment animals compared with those in the initial and reference groups, which did not mature (Le et al .…”

Changes in proximate composition, lipid class and fatty acid profile in Greenshell™ mussels (Perna canaliculus) over an annual cycle

“…There is little knowledge in the scientific literature on the seasonal variation in protein and carbohydrate content in GSM, but other mussel species (Perna perna) have shown seasonal changes (Benomar, Costil, el Filali, Mathieu, & Moukrim, 2010). Furthermore, there is lack of a detailed compositional and lipid analysis of GSM published over a whole year.…”