Wild Eggs Research Articles

Wild Eggs: a tale of Arctic Egg Collecting by S. Napayok – Short

Napayok – Short, Suzie. Wild Eggs: A Tale of Arctic Egg Collecting. Illus. Jonathan Wright. Iqaluit: Inhabit Media, Inc., 2015. Print.Wild duck eggs are a traditional food for Inuit people. This book is about a little girl, Akuluk, from Yellowknife who visits her grandparent in Nunavut and goes with them to gather duck eggs. This is a modern story that is told factually. Akuluk arrives in an aircraft, is picked up in a taxi van and her grandfather uses an all-terrain vehicle to go out onto the land. It is also a story that teaches traditional ways. Inuit words, such as munniit (eggs) and palaugaaq (bannock) are explained and appear in a pronunciation guide at the end of the book. The traditional ways, such as never taking nests that have more than four eggs in them, are explained as Akuluk’s grandfather teaches her.The text is overprinted on Jonathan Wright’s artwork. Parts of his pictures are quite clear and detailed, while others are suggestive and indistinct. This style works particularly well for the “almost invisible” caribou, “his brown and white fur match[ing] the rocks around him”.Wild Eggs is a clearly-written work that incorporates Inuit traditional knowledge with ease. The book is also available in Inuktitut and is recommended for school and public libraries and particularly for libraries that collect polar children’s literatureHighly Recommended: 4 stars out of 4Reviewer: Sandy CampbellSandy is a Health Sciences Librarian at the University of Alberta, who has written hundreds of book reviews across many disciplines. Sandy thinks that sharing books with children is one of the greatest gifts anyone can give.

Impact of the Egg Parasitoid, Gryon pennsylvanicum (Hymenoptera: Scelionidae), on Sentinel and Wild Egg Masses of the Squash Bug (Hemiptera: Coreidae) in Maryland.

Seasonal changes in egg parasitism and predation rates on sentinel (laboratory-reared) and wild (naturally occurring) egg masses of the squash bug, Anasa tristis (De Geer), were evaluated in squash fields in Maryland from June through September in 2013 and 2014. Rates of egg parasitism were significantly higher on wild egg masses than on sentinel egg masses. Squash bug nymphal emergence was significantly higher on sentinel egg masses than on wild egg masses. Between the first week of July and the first week of September of both survey years, squash bug nymphs emerged from 24.2% of wild eggs compared with 46.2% of sentinel eggs and parasitoids emerged from 55.7% of wild eggs compared with only 21.8% of sentinel eggs. Sentinel egg masses significantly underestimated the rate of natural egg parasitism. The egg parasitoid, Gryon pennsylvanicum (Ashmead), was responsible for over 99% of parasitism of squash bug eggs. There was a significant negative correlation between parasitoid emergence and nymphal emergence, suggesting that parasitoids were able to suppress squash bug populations. The average rate of parasitoid emergence peaked on wild egg masses on the fifth week of July at 72.8%, whereas the average rate of nymphal emergence from wild egg masses was <20% from the fifth week of July until the first week of September. These results demonstrate that G. pennsylvanicum was able to efficiently track wild squash bug eggs throughout the season and that it has the potential to be an effective biological control agent of the squash bug in Maryland.

Ark or park: the need to predict relative effectiveness of ex situ and in situ conservation before attempting captive breeding

Summary When species face extinction, captive breeding may be appropriate. However, captive breeding may be unsuccessful, while reducing motivation and resources for in situ conservation and impacting wild source populations. Despite such risks, decisions are generally taken without rigorous evaluation. We develop an individual‐based, stochastic population model to evaluate the potential effectiveness of captive‐breeding and release programmes, illustrated by the critically endangered Ardeotis nigriceps Vigors great Indian bustard. The model was parameterized from a comprehensive review of captive breeding and wild demography of large bustards. To handle uncertainty in the standards of captive‐breeding performance that may be achieved, we explored four scenarios of programme quality: ‘full range’ (parameters sampled across the observed range), ‘below average’, ‘above average’ and ‘best possible’ (performance observed in exemplary breeding programmes). Results are evaluated examining: (i) the probability of captive population extirpation within 50 years and (ii) numbers of adult females subsequently established in the wild following release, compared to an alternative strategy of in situ conservation without attempting captive breeding. Successful implementation of captive breeding, involving permanent retention of 20 breeding females and release of surplus juveniles, required collection of many wild eggs and consistent ‘best possible’ performance across all aspects of the programme. Under ‘full‐range’ and ‘above‐average’ scenarios, captive population extirpation probabilities were 73–88% and 23–51% respectively, depending on egg collection rates. Although most (73–92%) ‘best possible’ programmes supported releases, re‐establishment of free‐living adults also required effective in situ conservation. Incremental implementation of effective conservation measures over the initial 10 years resulted in more free‐living adults within 35 years if eggs were left in the wild without attempting captive breeding. Synthesis and applications. For the great Indian bustard Ardeotis nigriceps, rapid implementation of in situ conservation offers a better chance to avoid extinction than captive breeding. Demographic modelling of threatened species should be used to examine whether captive breeding will bring net benefits to conservation programmes.

Comparative study of lipids and fatty acids in the liver, muscle, and eggs of wild and captive common snook broodstock

Abstract In this study, the lipid composition of wild and captive common snook broodstock was investigated to identify potential nutritional deficiencies and formulate suitable diets for captive stocks. Results showed that captive snook incorporated significantly more lipid than their wild counterparts. However, cholesterol and arachidonic acid (ARA) levels were significantly lower compared to wild fish, which may impact steroid and prostaglandin production, reproductive behavior and gametogenesis. In eggs obtained from captive broodstock, high docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels, associated with low ARA contents were found. As a result, ARA/EPA ratio in captive eggs was less than half of that in wild eggs with the potential for negative consequences on embryo and larval development. In conclusion, large differences were noticed between wild and captive broodstock that may contribute to the reproductive dysfunctions observed in captive snook broodstock (e.g. incomplete oocyte maturation, low milt production and highly variable egg and larval quality). The wild snook survey also identified the presence of hydrocarbons in the liver, which should be further studied to identify a potential impact on the reproductive performances of a vulnerable population like common snook.

Fatty acid utilization during the early larval stages of Florida pompano (Trachinotus carolinus) and Common snook (Centropomus undecimalis)

The pattern of conservation and loss of fatty acids from the yolk sac during the endogenous feeding period and subsequent starvation was studied in pompano and snook larvae. Fundamental information on the early fatty acid dynamic and mobilization of pompano and snook larvae was collected. In both species, fatty acids were utilized as an energy source after hatching. Mono-unsaturated fatty acids were catabolized, while saturated and poly-unsaturated fatty acids were conserved. High levels of arachidonic acid (ARA) in pompano and snook eggs, as well as selective retention in the unfed larvae suggest a high dietary requirement for this fatty acid during the early stages of larval development. The effect of an ARA supplementation was therefore investigated in snook larvae at the rotifer feeding stage. The fatty acid profile of the larvae was successfully influenced to match that of wild eggs; however, no significant improvement in growth or survival was observed. Future research should be carried out over a longer period of time and include factors related to stress resistance.

Biochemical comparison between eggs from female Chinese sturgeon (Acipenser sinensis Gray, 1835) reconditioned in freshwater and eggs from wild females: evaluation of female reconditioning as a conservation culture technique

Summary Chinese sturgeon (Acipenser sinensis Gray, 1835) eggs from wild females (‘wild eggs’) and eggs from females reconditioned in freshwater (‘freshwater eggs’) were compared for biochemical factors related to their good chemical and physical condition and successful fertilization. Dry weights did not differ between the two groups of eggs. Wild eggs had a significantly higher protein content but lower lipid content than freshwater eggs. There were multiple and significant differences in the fatty acids between eggs from the two groups, but there was no difference for vitellin (Vn). The levels of phosphorus (P), magnesium (Mg), vitamin A (VA) and vitamin E (VE) in wild eggs were significantly higher than in freshwater eggs, but calcium (Ca) and zinc (Zn) levels did not differ between the two groups. These results can be used to discriminate wild eggs and reconditioned eggs. Also suggested is to decrease lipids and increase protein levels in freshwater eggs for better egg quality. Mg, P, VA and VE should also be given as sturgeon food supplements.

Sentinel eggs underestimate rates of parasitism of the exotic brown marmorated stink bug, Halyomorpha halys

Native to eastern Asia, the brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), has become a serious invasive pest in North America. Consequently, accurate assessment of parasitism rates under field conditions is critical for determining baseline parasitism rates of native egg parasitoids on BMSB, and for future evaluations of native or exotic parasitoid biological control release strategies and impacts. BMSB sentinel (laboratory-laid) egg masses have typically been used for this purpose, even though they could be providing misleading estimates of parasitoid activity. Accordingly, we compared the use of BMSB sentinel (laboratory-laid) and wild (naturally field-laid) egg masses in 2012 and 2013 to examine rates of parasitism and the parasitoid community composition of indigenous egg parasitoids in outdoor ornamental nurseries. Wild egg masses consistently had higher rates of parasitism than sentinel egg masses. In 2012, wild egg masses had a mean percent parasitism of 28.4% compared to 4.6% in sentinel egg masses, while in 2013 the difference between the two methods increased even further with a mean percent parasitism of 55.3% in wild egg masses compared to 0.8% in sentinel eggs. Furthermore, we found greater total numbers of parasitoids (889, 42) and greater species richness (seven, five), when using wild egg masses compared to sentinel egg masses, respectively. While sentinel egg masses provide a rapid and convenient way to assess the presence of natural enemies, our findings indicate that using sentinel egg masses could dramatically underestimate actual rates of parasitism and provide inaccurate estimates of parasitoid community composition. Future studies should address potential mechanisms underlying these patterns such as lack of certain host cues required by parasitoids in sentinel compared to wild egg masses.

Hologenomic speciation: synergy between a male-killing bacterium and sex-linkage creates a ‘magic trait’ in a butterfly hybrid zone

Danaus chrysippus (L.) in Africa comprises four substantially isolated semispecies that are migratory and hybridize on a seasonal basis throughout the eastern and central part of the continent. In the hybrid zone (but not elsewhere), the butterfly is commonly host to a male killing endosymbiotic bacterium, Spiroplasma sp., which principally infects one semispecies, Danaus chrysippus chrysippus in Kenya. A W-autosome mutation, inherited strictly matrilinearly, links B and C colour gene loci, which have thus gained sex-linkage in chrysippus. We have monitored variation in sex ratio and genotype at the A and C colour gene loci for two extended periods of 18 months (2004–5) and 12 months (2009–10) in adults reared from wild eggs laid on trap plants in Kasarani, near Nairobi, Kenya. Additionally, in 2009–10, all surviving adult butterflies were screened for Spiroplasma infection. The hybridizing Kasarani population is highly atypical in three respects, and has apparently been so for some 30 years: first, the sex ratio is permanently female-biased (as expected), although subject to seasonal fluctuation, being lowest (male/female) when D. c. chrysippus (cc) peaks and highest when Danaus chrysippus dorippus (CC) predominates; second, the population is invariably dominated by Cc heterozygotes of both sexes but especially females; and third, cc males are always scarce because they are systematically eliminated by male killing, whereas the CC genotype is male-biased. It is this imbalance of sex versus genotype that determines the massive departure from Hardy–Weinberg equilibrium in the population, in part because cc females have little choice but to pair with C- males. We suggest that: first, Cc hybrids of both sexes fail to disperse in the company of either parental semispecies; second, Spiroplasma positive females carrying the W-autosome mutation have a selective advantage over females that lack the translocation; third, the endoparasite and the translocation create a ‘magic trait’ linkage group that underlies hologenomic reproductive isolation between two emerging species, D. c. chrysippus and D. c. dorippus; and, fourth, that the predominance of males in dorippus suggests that individuals must be protected by a male-killing suppressor gene. By contrast to the C locus, Aa heterozygotes are in substantial and permanent deficit, suggesting either assortative mating between AA (chrysippus and dorippus) and aa (Danaus chrysippus alcippus), or heterozygote unfitness, or both. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111, 92–109.

How have spawning ground investigations of the Japanese eel Anguilla japonica contributed to the stock enhancement?

After Schmidt’s discovery of the spawning area of the Atlantic eels Anguilla anguilla and A. rostrata, the search for the Japanese eel A. japonica began in the Pacific Ocean. In 1991, the spawning area of the Japanese eel was determined to be the western North Pacific. Because of enthusiastic research, eggs and maturing eels have been collected in the Japanese eel. These findings are the first for one of the 19 freshwater eels. The population sizes of the Japanese and Atlantic eels are linearly decreasing. Thus, these eel population sizes are considered outside of safe biological limits, and the current fisheries are not sustainable. Artificial propagation has not yet succeeded for the freshwater eels. Stock assessment and management of the European eel have received increasing attention; however, such assessments and management of the Japanese eel have not yet been seriously considered. This paper is an overview of the results of intensive spawning ground investigations of the Japanese eel and describes how the outcomes of these studies have contributed not only to biological interests but also to stock enhancement. During the past 20 years of expeditions, noticeable findings have only been collected for wild eggs and mature adult specimens in spite of the expenditure of large research grants and the large amounts of time invested. The outcomes throughout an expedition do not necessarily contribute to the development and improvement of artificial breeding techniques and stock enhancement. Thus, eel research should be more focused on the studies related to eel stock management.

Can fatty acid and mineral compositions of sturgeon eggs distinguish between farm-raised versus wild white (Acipenser transmontanus) sturgeon origins in California? Preliminary report

The objective was to investigate the potential of using fatty acid and mineral compositions of sturgeon eggs to distinguish their source, either farm-raised or wild fish. Trafficking of illegally obtained wild white sturgeon eggs is a major concern to the California Department of Fish and Game, but there is no forensic method to separate wild and farm-raised white sturgeon eggs. The extension of these findings in future work will be to use the fatty acid and mineral compositions as forensic indicators of caviar produced legally from farm raised sturgeon compared with illegal caviar produced from sturgeon poached from the wild. Samples (10) of sturgeon eggs were collected from a commercial aquaculture facility in the Sacramento Valley. Eggs from wild sturgeon (9) were obtained primarily from confiscations of illegally caught sturgeon by fish and game law enforcement personnel. The total lipid content of sturgeon eggs was analyzed for fatty acid composition. The most notable difference was the higher concentration (P<0.001) of C18:2n6 in farm raised eggs (6.5mg/100g total lipid) than wild eggs (0.6mg/100g total lipid) while other differences between fatty acids were smaller. Eicosapentaenoic acid (C20:5n3) was higher (P<0.02) in farm-raised (5.56mg/100g) than wild (4.49mg/100g). Docosahexaenoic acid (C22:6n3), C18:1 cis 9&10, and C20:4n6 were not different for origin of the eggs. Concentration of selenium was markedly higher (P<0.001) in eggs from wild sturgeon (10.0mg/kg dry weight) than farm-raised sturgeon (2.7mg/kg dry weight). Concentrations of iron, zinc, copper, phosphorus, sulfur, calcium, and potassium did not differ between farm-raised and wild eggs. Arsenic concentration in wild eggs was 3.3mg/kg dry weight whereas arsenic was not detected in the farm-raised eggs. Fatty acid and mineral compositions of eggs differed significantly between farm-raised and wild sturgeon and these should be investigated further as biological markers for forensic identification of caviar origin.

Fatty acid profile in eggs and newly hatched paralarvae of Octopus vulgaris collected from the wild, and after 1-5 days starvation.

High paralarvae mortality still limits the industrial rearing of O. vulgaris, related to the unknown nutritional requirements of early stages (Iglesias et al., 2007). Several studies suggested the importance of n-3 HUFA in this species, particularly EPA and DHA (Navarro and Villanueva, 2000). However, very little is known regarding the initial planktonic phase of O. vulgaris (Villanueva and Norman, 2008) and the natural biochemical profile of newly hatched paralarvae is also unknown. 1. Obtain the “natural” fatty acid profile of wild eggs and wild paralarvae → information regarding broodstock natural diet. 2. Compare the fatty acid profile between wild paralarvae and paralarvae from broodstock fed on low price fish species → paralarvae quality? 3. Five-day starving trial → evaluate lipid and fatty acid utilization. Introduction Objectives

Presence of Red Fire Ants (Solenopsis invictaBuren) in Broad-Snouted Caiman (Caiman latirostris) Nests

Abstract The presence of Solenopsis invicta in Caiman latirostris nests is suspected to be a possible cause of death in caiman hatchlings, but this has not been documented within the native distribution of this ant. In crocodilian ranching programs, wild eggs are collected from the field, and delays between collection and transportation to incubators are usually minimized in the hope of maximizing embryo survival. We analyzed nests harvested during five consecutive nesting seasons of C. latirostris to determine the phenology of S. invicta colonization of caiman nests. The percentages of colonized caiman nests for each season were calculated. Densities of S. invicta mounds built on bare ground were assessed to determine potential relationships between density and the proportion of caiman nests colonized by the end of nesting season. We also evaluated whether S. invicta preferred certain habitats to establish their mounds. We found no relationship between S. invicta mound densities and the percentage of C. ...

ISOLATION OF SALMONELLA SPP. FROM YACARE CAIMAN (CAIMAN YACARE) AND BROAD-SNOUTED CAIMAN (CAIMAN LATIROSTRIS) FROM THE ARGENTINE CHACO

Presence of Salmonella spp. was evaluated in yacare caiman (Caiman yacare) and broad-snouted caiman (Caiman latirostris) from a ranching facility in the Argentine Chaco. Crocodilian ranching programs are based on captive breeding of wild-harvested eggs and release of excess hatchlings into the wild. Samples for bacterial isolation were collected from 102 captive (35 C. yacare and 67 C. latirostris) and seven free-ranging caiman (four C. yacare and three C. latirositris) between 2001 and 2005 and from three artificially incubated C. yacare wild eggs. Two Salmonella spp. of known zoonotic potential, S. infantis and S. nottingham, were isolated from captive caiman in 2001 and 2002, respectively. This is the first report for S. nottingham in reptiles and of S. infantis in caiman. Salmonella spp. prevalence varied significantly between years, with a 77% prevalence peak in 2002. Although the cause of this increase was not confirmed, we found no correlation with the type of enclosure, caiman species, or body weight. Deteriorated physical condition of caiman hatchlings due to dietary changes in 2002 could have influenced Salmonella spp. shedding. However, external sources such as food, water, or enclosures could not be ruled out. Pathogenic Salmonella spp. present a risk for human infection. Inadvertent introduction of Salmonella spp. or other bacteria into the environment when caiman are released could pose a threat to wild caiman populations. Prophylactic measures to detect and decrease Salmonella spp. presence in caiman ranching facilities are recommended to reduce risk to humans and make caiman-ranching a sound conservation strategy for crocodilian species.

A molecular approach to identifying the prey of cephalopod paralarvae

Abstract Roura, Á., González, Á. F., Pascual, S., and Guerra, Á. 2010. A molecular approach to identifying the prey of cephalopod paralarvae. – ICES Journal of Marine Science, 67: 1408–1412. A molecular method was developed to detect Artemia franciscana within Octopus vulgaris paralarvae, as a first step towards understanding the diet of octopus during this life stage. Wild eggs were collected from a spawning female in the Ría de Vigo (northwestern Spain) in late summer, and brought to the laboratory. After hatching, paralarvae were reared in 30 l rectangular tanks with an open seawater filtered system. Paralarvae were fed Artemia, then immediately fixed in 80% ethanol and preserved at −20°C. Primers specific to A. franciscana were designed for the gene cytochrome c oxidase subunit I. A nested polymerase chain reaction was necessary to detect A. franciscana within octopus paralarvae. This molecular method provides a new framework for resolving the diet of cephalopod paralarvae in the wild, essential for ecological understanding and increasing survival rates in aquaculture.

The use of polymerase chain reaction for the identification of sciaenid eggs

Traditionally, sciaenid eggs have been identified based on morphological characteristics such as size, number of oil globules and/or pigmentation patterns. Identification of sciaenid eggs by these procedures is time consuming and often inaccurate due to considerable egg size overlap among species. The utilization of molecular techniques for the identification of economically important species has become a fundamental component in ecological studies involving fish eggs and larvae. This study reports the development of a series of both multiplex and individual polymerase chain reactions to identify the eggs of 11 sciaenid species commonly found in the Gulf of Mexico and estuaries near Port Aransas and Corpus Christi, TX, USA. Following method development, the discriminatory power of the assay was first determined with samples from adult fish collected from Aransas and Corpus Christi Bays, Galveston Bay and the lower Laguna Madre in northern Mexico. Most (97%) of these fishes were correctly identified to the level of species. To demonstrate the applicability of the assay, wild fish eggs were collected and analyzed from the Aransas Pass tidal inlet from September through December 2005. During this period, the eggs of four target species were positively identified which was in keeping with current knowledge regarding the spawning areas and seasons of these sciaenids based on the presence of mature females, eggs and/or larvae. Future use of this method can provide valuable information to better discriminate spawning sites and seasons of these species.

Eggshell Thickness Variation in Red-legged Partridge (Alectoris rufa) from Spain

Eggshell thickness is commonly used as an indicator of habitat quality and effects of environmental pollution on avian reproduction. We present the first data available on eggshell thickness for Red-legged Partridge (Alectoris rufa) in Spain. We compared eggshell thickness between eggs collected in an agricultural area (wild eggs) and eggs from game farms (farm eggs). Wild eggs had shells significantly thicker (x̄ = 0.32 mm, n = 74) than farm eggs (x̄ = 0.28 mm, n = 89), despite game farm partridges being fed a diet rich in calcium and not exposed to agricultural pollutants. Eggshell thickness did not affect hatching success of wild partridges, and population decline observed in this species cannot be linked to reduction in egg viability due to eggshell thickness.

Natural egg mass deposition by the Humboldt squid (Dosidicus gigas) in the Gulf of California and characteristics of hatchlings and paralarvae

The jumbo or Humboldt squid, Dosidicus gigas, is an important fisheries resource and a significant participant in regional ecologies as both predator and prey. It is the largest species in the oceanic squid family Ommastrephidae and has the largest known potential fecundity of any cephalopod, yet little is understood about its reproductive biology. We report the first discovery of a naturally deposited egg mass of Dosidicus gigas, as well as the first spawning of eggs in captivity. The egg mass was found in warm water (25–27°C) at a depth of 16 m and was far larger than the egg masses of any squid species previously reported. Eggs were embedded in a watery, gelatinous matrix and were individually surrounded by a unique envelope external to the chorion. This envelope was present in both wild and captive-spawned egg masses, but it was not present in artificially fertilized eggs. The wild egg mass appeared to be resistant to microbial infection, unlike the incomplete and damaged egg masses spawned in captivity, suggesting that the intact egg mass protects the eggs within. Chorion expansion was also more extensive in the wild egg mass. Hatchling behaviours included proboscis extension, chromatophore activity, and a range of swimming speeds that may allow them to exercise some control over their distribution in the wild.

Variation in Reproductive Performance and Egg Quality Between Wild and Pond-Reared Indian White Shrimp, Fenneropenaeus indicus, Broodstock

ABSTRACT The shrimp hatchery industry worldwide has placed immense interest on the production of closed-life cycle broodstock from farm stock. Unfortunately, majority of the studies have proven that pond-reared broodstock are inferior to their wild counterparts in terms of reproductive performance, spawn quality and post-hatching performance. In the present study, reproductive performance, egg, and nauplii quality of wild and pond-reared Indian white shrimp, Fenneropenaeus indicus, broodstock were analyzed. Biochemical analyses were done with egg and nauplii from both the sources, in an attempt to explain the difference in their performance. Results indicated better reproductive performance by wild females compared to pond-reared ones. The wild eggs contained higher total lipid, and vital HUFAs namely EPA (Eicosapentaenoic acid), DHA (Docosahexaenoic acid) and ARA (Arachidonic acid). However, one of the dominant PUFA, 18:2 (n-6) was high in pond broodstock eggs. Biochemical analysis also indicated that glucose, carotenoids, and triacylglycerol content were significantly higher (P < 0.001) in wild eggs. But, egg protein and triacylglycerol content did not record significant difference between the egg samples. The percentage viable nauplii, nauplii length and triacylglycerol content were all significantly higher (P < 0.05) with wild nauplii. This study proves the better nutritional profile of wild eggs and nauplii in terms of analyzed biochemical components. But, as our knowledge on specific nutrient requirement for successful reproductive performance and offspring quality is limited, the better performance of wild eggs could not be attributed to any single nutrient. Meanwhile, it could be presumed that all the deficient nutrients collectively contributed to the poor reproductive performance and spawn quality.

Lipid characterization of both wild and cultured eggs of cuttlefish (Sepia officinalisL.) throughout the embryonic development

The present work reports a characterization of mean wet weight and moisture, the lipid class and fatty acid (FA) composition from the total lipids (TL), of both culture and wild eggs of the cuttlefish, Sepia officinalis, throughout the embryonic development. Additionally, reproductive data, such as the number of spawnings, number and mean weight of eggs and duration of spawning period of cultured cuttlefish is provided. Both types of eggs were similar in mean wet weight, moisture content, TL content and lipid composition throughout embryonic development. Females from the cultured group spawned 13 times and laid 8654 eggs in 64 days, with a mean weight of 0.607 ± 0.179 g. A sex ratio of 1.57 (11♀ for 7♂) promoted an individual fecundity of 787 eggs/♀ (the biggest until now on our culture facilities), which might be related to increased bottom areas. The TL increased with day/stage of embryonic development (P 0.05). Eggs displayed predominant levels of phosphatidylcholine, phosphatidylethanolamine (PE), cholesterol and triacylglycerol at the end of embryonic development. Polar and neutral lipids of both eggs groups remained consistently proportional (∼50% for each lipid fraction) and a significant increase (P < 0.05) was observed in phosphatidylserine, PE and free FA throughout the embryonic development. In either egg type and day, 16:0, 18:0, 20:5n-3 and 22:6n-3 accounted for approximately 70 g Kg−1 of all FA and saturated and n-3 totals seemed to have the same proportion in the cuttlefish eggs. The present results suggest that lipids are not used as energetic substrate but as structural components in cuttlefish egg.

DSTAM expression pattern during wild type and mutant egg chamber development in D. melanogaster

STAM (signal-transducing adaptor molecule) is a protein highly conserved from yeast to mammals. In Drosophila melanogaster the basic molecular architecture of the protein is comprised of a N-terminal VHS domain, an ubiquitin-interacting motif and a central Src homology-3 domain. In this paper we examine the expression pattern of the stam gene and the localisation of the STAM protein during D. melanogaster oogenesis. Its transcript is present throughout egg chamber development in all germ-line cells, including the oocyte. dSTAM is firstly detected in germarial region 2, where the protein is present in the newly formed germ-line cysts and is mainly accumulated into the oocyte. As oogenesis proceeds, dSTAM is enriched in the perinuclear region of the nurse cells and is also found in the somatic polar follicular cells. In the oocyte, the protein is more abundant posteriorly and becomes restricted to the posterior pole just before disappearing at stage 10b. We show that dSTAM localisation is unaffected in the oocyte of grk mutant egg chambers, indicating that it is not dependent on the polarity of the microtubule network. In contrast, dSTAM distribution is remarkably altered in cup mutant oocytes where the protein accumulates in a round central spot and never reaches the posterior pole.