Pathogenic effect of microorganisms on loggerhead eggs

[EN] Different types of fungi and bacteria have been isolated from hatched and non-hatched as well as failed and non-failed eggs in natural sea turtles nests (Marco et al. 2006, Phillott and Parmenter, 2001, Phillott et al. 2001). Microbiota infections are common in artificial incubation activities and they seem to have an important negative impact on embryo development (Phillott, 2002). However, no clear evidences of their pathogenic effects have been described. The aim of this study was to investigate whether fungi and bacteria represent pathogenic agents to sea turtle eggs, and to assess whether there exists a specific period during incubation in which eggs are more susceptible to microorganisms.

Influence of loggerhead egg agregation on survival: why does single eggs buried into natural sand dye in few days?

[EN] The incubation is an essential life period for oviparous species that very often experiences a high mortality. In some reptile species the number of eggs that develop together in the incubation chamber affects survival and hatchling phenotype. Sea turtle eggs develop in underground locations on sandy beaches in large masses that usually have more than 80 eggs. Natural egg mortality seems to vary among species and for the sensitive leatherbacks, external eggs seems to survive better than internal ones within the nest.

Natural colonization of loggerhead turtle eggs by the pathogenic fungus Fusarium oxysporum

[EN] Sea turtle nests are exposed to different environmental risks that may affect their hatching success. Human exploitation, predation by wild or domestic animals, nest flooding or severe beach erosion or accession are common causes of egg mortality. However, there is very little information about the impact of microorganisms on turtle eggs. We analyzed loggerhead turtle eggs from Boavista Island (Republic of Cabo Verde) which were incubated under different environmental conditions in order to evaluate the presence and impact of fungus. We have isolated Fusarium oxysporum from dead and live eggs after three days of incubation.

Comparative study between the effects of hyaluronic acid and acid galactan purified from eggs of the mollusk Pomacea sp in wound healing

To compare the effect of hyaluronic acid (HA) and of AG on the healing of intestine wounds. Methods: The semi-purified extract of the eggs of the mollusc was obtained by fractionation with ammonium sulfate and purification for ion-exchange chromatography. The obtained galactans were eluted in water (neutral galactan) and in 0.1 and 0.2M NaCl (acidic galactans). The in vivo study was performed with 45 “Wistar” rats, separated in three groups (n=15). Solutions containing HA 1%, GA 1% or saline solution 0,9%, was placed topically on the sutures of wounds in the small intestine of the rats. After 05, 10 and 21 days the animals were sacrificed and biopsy of the healing tissue was done. Results: The hystologic grading was more significant for HA and AG groups when compared to the group C. AG stimulated the appearance of macrophages, giant cells and increase in the concentration of collagen in the area of the wound when compared to HA. Conclusion: The topical use of GA in intestinal wounds promoted the anticipation of events that are important in the wound healing

Trichogramma canariensis (Insecta: Hymenoptera: Trichogrammatidae) a parasitoid of eggs of the twinspot moth Chrysodeixis chalcites (Lepidoptera: Noctuidae) in the Canary Islands

A new species of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) parasitizing eggs of the golden twin-spot moth (or tomato looper) Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) on banana crops in the Canary Islands, Spain, is described as Trichogramma canariensis del Pino & Polaszek, sp.n. The new species is closely related to T. brassicae Bezdenko. Limited aspects of morphology, coupled with ITS2 and COI sequences and reproductive data are presented to distinguish T. canariensis sp.n. from T. brassicae.

Isolation and recognition Saprolegnia species from fungal infected eggs of the rainbow trout in Mazandaran province farms

Fungal infection in the eggs of freshwater fish is well known as a problematic disease. That isolation and recognition Saprolegnia fungi from fungal infected eggs of the rainbow trout in Mazandaran province was the aim of this research. For this purpose fungal infected eggs were examined from six fish farm in the fall and winter 2005-2006. The eggs with fungi were inoculated on SDA, CMA, GPagar and hemp seed and sesame seed cultures in sterile tap water at room temperature (18-24°C). In this study recognized three genera and six species Saprolegniaceae members, based on morphological characteristics which contain: Saprolegnia, Achlya, Brevilegnia. Four species were identified in the genus Saprolegnia; S.mixta, S.parasitica, S.moniliphera, S.lapponica and one species was identified in the genus Achlya; A.oblongata. S.parasitica was isolated from almost all the farms. In addition, another nine genera and species were identified; Penicillium, Aspergillus, Paeciliomyces, Acremonium, Fusarium oxysporum, F.solani , Alternaria, Helminthosporium, Mucor.

Biofloc contribution to antioxidant defence status, lipid nutrition and reproductive performance of broodstock of the shrimp Litopenaeus stylirostris: Consequences for the quality of eggs and larvae

The aim of this study was to determine biofloc contributions to the antioxidant status and lipid nutrition of broodstock of Litopenaeus stylirostris in relationship with their reproductive performance and the health of larvae produced. Shrimp broodstock reared with Biofloc technology (BFT) compared to Clear water (CW) exhibited a higher health status with (i) a better final survival rate during the reproduction period (52.6% in CW against 79.8% in BFT); (ii) higher glutathione level (GSH) and total antioxidant status (TAS), reduced oxidized/reduced glutathione ratio and a higher spawning rate and frequency as well as higher gonado-somatic index and number of spawned eggs. Finally, larvae from broodstock from BFT exhibited higher survival rates at the Zoe 2 (+ 37%) and Post Larvae 1 (+ 51%) stages when compared with those from females from CW treatment. The improved reproductive performance of the broodstock and higher larvae survival rate resulting from BFT treatment may be linked to the dietary supplement obtained by the shrimp from natural productivity during BFT rearing. Indeed, our study confirms that biofloc particulates represent a potential source of dietary glutathione and a significant source of lipids, particularly essential phospholipids and n-3 highly unsaturated fatty acids (HUFA) for shrimps. Thus, broodstock from BFT treatment accumulated phospholipids, n-3 HUFA and arachidonic acid, which are necessary for vitellogenesis, embryogenesis and pre-feeding larval development. The predominant essential fatty acids, arachidonic acid (ARA), eicopentaeonic acid (EPA) and docosahexaenoic acid (DHA), had levels in the eggs that were, respectively, 2.5, 2.8 and 3 fold higher for BFT compared to the CW treatment. Statement of Relevance Today, the influence of biofloc technology on shrimp broodstock is not enough described and no information was available on the larvae quality. Moreover, two key pieces of new information emerge from the present study. Firstly, biofloc is a source of further dietary lipids that can act as energetic substrates, but also as a source of phospholipids and essential fatty acids necessary to sustain reproduction, embryonic and larval development. Second, improving the reproduction of the broodstock also leads to an improvement in the quality of the larvae. We think that our research is new and important to increase knowledge on biofloc topic. We believe the paper will contribute to the development of more efficient and therefore more sustainable systems.

Comparative study between the effects of hyaluronic acid and acid galactan purified from eggs of the mollusk Pomacea sp in wound healing

To compare the effect of hyaluronic acid (HA) and of AG on the healing of intestine wounds. Methods: The semi-purified extract of the eggs of the mollusc was obtained by fractionation with ammonium sulfate and purification for ion-exchange chromatography. The obtained galactans were eluted in water (neutral galactan) and in 0.1 and 0.2M NaCl (acidic galactans). The in vivo study was performed with 45 “Wistar” rats, separated in three groups (n=15). Solutions containing HA 1%, GA 1% or saline solution 0,9%, was placed topically on the sutures of wounds in the small intestine of the rats. After 05, 10 and 21 days the animals were sacrificed and biopsy of the healing tissue was done. Results: The hystologic grading was more significant for HA and AG groups when compared to the group C. AG stimulated the appearance of macrophages, giant cells and increase in the concentration of collagen in the area of the wound when compared to HA. Conclusion: The topical use of GA in intestinal wounds promoted the anticipation of events that are important in the wound healing

Hookworm-like eggs in children’s faecal samples from a rural area of Rwanda.

Background: Hookworm eggs identification and quantification is usually carried out by Kato-Katz method. However various structures present in the smear may be confused with eggs of such parasites. Objective: To document the presence of structures in Kato-Katz slides that could initially be misinterpreted as hookworm eggs. Method: 497 faecal samples were analysed by Kato-Katz technique, diphasic concentration technique, agar-plate coprocultive and larvae obtained were analysed by PCR and characterized by sequencing. Results: Hookworm-like eggs were found in 159 (32%) of the samples by Kato-Katz, finally identified as Caenorhabditis elegans by PCR technique. Conclusion: The diagnosis of human hookworm eggs, only by the use of Kato-Katz technique can lead to false positives because of similarities with eggs of other free-living worms, from wet soils like those of Rwanda that could contaminate stool samples.

Development and reproduction of Olla v-nigrum (Coleoptera: Coccinellidae) fed Anagasta kuehniella (Lepidoptera: Pyralidae) eggs supplemented with an artificial diet.

2013

Natural parasitism of lepidopteran eggs by Trichogramma species (Hymenoptera: Trichogrammatidae) in agricultural crops in Minas Gerais, Brazil.

The genus Trichogramma Westwood (Hymenoptera: Trichogrammatidae) includes insect egg parasitoids that are widely used throughout the world as control agents of pest insects. The aim of this study was to identify the species of Trichogramma naturally associated with the eggs of lepidopteran pests of the following agricultural and horticultural crops: collards, Brassica oleracea L. (Brassicales: Brassicaceae); papaya, Carica papaya L. (Capparales: Caricaceae); tomato, Lycopersicon esculentum Mill. (Solanales: Solanaceae); cassava, Manihot esculenta Crantz (Malpighiales: Euphorbiaceae); banana, Musa sp. L. (Zingiberales: Musaceae); passion fruit, Passiflora sp. Degener (Malpighiales: Passifloraceae); sugarcane, Saccharum sp. L. (Poales: Poaceae); and corn (maize), Zea mays L. (Poales: Poaceae); and an invasive species (Sodom?s apple milkweed, Calotropis procera Aiton; Gentianales: Apocynaceae) in the semiarid region of Minas Gerais, Brazil. We report natural parasitism by Trichogramma in eggs of Agraulis vanillae vanillae (L.) (Lepidoptera: Nymphalidae), Antichloris eriphia F. (Lepidoptera: Arctiidae), Danaus sp. (L.) (Lepidoptera: Nymphalidae), Diatraea saccharalis F. (Lepidoptera: Crambidae), Erinnyis ello L. (Lepidopera: Sphingidae), and Protambulyx strigilis L. (Lepidopera: Sphingidae). In total, 2,242 specimens of Trichogramma were obtained, belonging to the species T. pretiosum Riley, T. manicobai Brun, Moraes & Soares, T. marandobai Brun, Moraes & Soares, and T. galloi Zucchi. These species of Trichogramma may be candidates for biological control programs of lepidopteran pests in the semiarid region of Minas Gerais and in other semiarid regions.

Analysis of the failure of cracked biscuits

Cracks or checks in biscuits weaken the material and cause the product to break at low load levels that are perceived as injurious to product quality. In this work, the structural response of circular digestive biscuits, with diameter 72 mm and thickness 7.2 mm, simply supported around the circumference and loaded by a central concentrated force was investigated by experiment and theory. Tests were conducted to quantify the distribution in breakage strength for structurally sound biscuits, biscuits with natural checks and biscuits with a single known part-through crack. For sound biscuits the breakage force is Normally distributed with a mean of 12.5 N and standard deviation of 1.2 N. For biscuits with checks, the corresponding statistics are 9.6 N ± 2.62 N respectively. The presence of a crack weakens the biscuit and strength, as measured by breakage force falls almost linearly with crack length and crack depth. The orientation of the crack, whether radial or tangential, and its location (i.e. position of the crack mid-point on the biscuit surface) are also important. Deep, radial, cracks located close to the biscuit centre can reduce the strength by up to 50%. Two separate failure criteria were examined for sound and cracked biscuits respectively. The results from these tests were in good accord with theory. For a biscuit without defects, breakage occurred when maximum biscuit stress reached or exceeded the failure stress of 420 kPa. For a biscuit with cracks, breakage occurred as above or alternatively when its critical stress intensity factor of 18 kPam0.5 was reached.

The influence of volatile semiochemicals from stink bug eggs and ovipositiondamaged plants on the foraging behaviour of the egg parasitoid Telenomus podisi.

2016

The Effect of Eggs Shape Index on Embryo on Mortalities, Unhatched Eggs and Day Old duck Abnormalities of Selected and Control Tegal Duck

An experiment was conducted to study the effect of eggs shape index on embryo mortalities, unhatched egg and day old duck abnormalities of selected and control Tegal duck. A total of 1428 fertile eggs obtained from a selected duck group and a control group were divided in to 3 group according to their eggs shape index (ESI), i.e. small (ESI ,79 percent), medium ( ESI ,82 percent ) and large (ESI ,85 percent ). The ESI was measured as a ratio of wide and length of eggs and percentage. Three batches of incubation with 7 day interval were carried out as replicates. Parameter measured were embryo mortalities, number of unhatched eggs and number of abnormal day old duck. Candling of eggs were performed at 6, 14 and days of incubation and mortalities of embryo were detected by loup. Results of the experiment showed that lowest embryos mortalities was occurred on medium eggs (24 percent) and significantly ( p< 0,05 ) affected by eggs size. Abnormal DOD from medium eggs was significantly (p ,0,05 ) lower (13 percent ) than the small (23 percent ) and large (21 percent ) eggs. Similar trends on eggs from selected duck and control ducks. This may be due to short term of selection program and young age of the female duck (24 weeks ). These results conclude that medium eggs (ESI ,82 percent) were the best size for hatching eggs. (Animal Production 2(1): 25-32 (2000)Key word : duck , hatching eggs, selection, eggs shape index

Host searching behaviour of Diachasmimorpha kraussii (Fullaway) (Hymenoptera: Braconidae: Opiinae), a polyphagous parasitoid of Dacinae fruit flies (Diptera: Tephritidae)

Diachasmimorpha kraussii (Hymenoptera: Braconidae: Opiinae) is a koinobiont larval parasitoid of dacine fruit flies of the genus Bactrocera (Diptera: Tephritidae) in its native range (Australia, Papua New Guinea, Solomon Islands). The wasp is a potentially important control agent for pest fruit flies, having been considered for both classical and inundative biological control releases. I investigated the host searching, selection and utilisation mechanisms of the wasp against native host flies within its native range (Australia). Such studies are rare in opiine research where the majority of studies, because of the applied nature of the research, have been carried out using host flies and environments which are novel to the wasps. Diachasmimorpha kraussii oviposited equally into maggots of four fruit fly species, all of which coexist with the wasp in its native range (Australia), when tested in a choice trial using a uniform artificial diet media. While eggs laid into Bactrocera tryoni and B. jarvisi developed successfully through to adult wasps, eggs laid into B. cucumis and B. cacuminata were encapsulated. These results suggest that direct larval cues are not an important element in host selection by D. kraussii. Further exploring how D. kraussii locates suitable host larvae, I investigated the role of plant cues in host searching and selection. This was examined in a laboratory choice trial using uninfested fruit or fruit infested with either B. tryoni or B. jarvisi maggots. The results showed a consistent preference ranking among infested fruits by the wasp, with guava and peach most preferred, but with no response to uninfested fruits. Thus, it appears the wasp uses chemical cues emitted in response to fruit fly larval infestation for host location, but does not use cues from uninfested fruits. To further tease apart the role of (i) suitable and non-suitable maggots, (ii) infested and uninfested fruits of different plant species, and (iii) adult flies, in wasp host location and selection, I carried out a series of behavioural tests where I manipulated these attributes in a field cage. These trials confirmed that D. kraussii did not respond to cues in uninfested fruits, that there were consistent preferences by the wasps for different maggot infested fruits, that fruit preference did not vary depending on whether the maggots were physiologically suitable or not suitable for wasp offspring development, and finally, that adult flies appear to play a secondary role as indicators of larval infestation. To investigate wasp behaviour in an unrestrained environment, I concurrently observed diurnal foraging behaviours of both the wasp and one of its host fly in a small nectarine orchard. Wasp behaviour, both spatially and temporally, was not correlated with adult fruit fly behaviour or abundance. This study reinforced the point that infested fruit seems to be the primary cue used by foraging wasps. Wasp and fly feeding and mating was not observed in the orchard, implying these activities are occurring elsewhere. It is highly unlikely that these behaviours were happening within the orchard during the night as both insects are diurnal. As the final component of investigating host location, I carried out a habitat preference study for the wasp at the landscape scale. Using infested sentinel fruits, I tested the parasitism rate of B. tryoni in eucalyptus sclerophyll forest, rainforest and suburbia in South East Queensland. Although, rainforest is the likely endemic habitat of both B. tryoni and D. kraussii, B. tryoni abundance is significantly greater in suburban environments followed by eucalyptus sclerophyll forest. Parasitism rate was found to be higher in suburbia than in the eucalyptus sclerophyll forest, while no parasitism was recorded in the rainforest. This result suggests that wasps orient within the landscape towards areas of high host density and are not restricted by habitat types. Results from the different experiments suggest that host searching, selection and utilisation behaviour of D. kraussii are strongly influenced by cues associated with fruit fly larval feeding. Cues from uninfested fruits, the host larvae themselves, and the adult host flies play minimal roles. The discussion focuses on the fit of D. kraussii to Vinson’s classical parasitoid host location model and the implications of results for biological control, including recommendations for host and plant preference screening protocols and release regimes.