Effects of feeding with different live preys on the lipid composition,growth and survival of Octopus vulgaris paralarvae

To move forward in the farming of Octopus vulgaris paralarvae, it is necessary to search for a live prey easy to obtain and maintain in the laboratory that meets the nutritional requirements of the octopus paralarvae and adapts to its predatory behaviour. Grapsus adscensionis zoeae (Crustacea, Decapoda) seems to fulfil most of these targets, and it was herein used to deepen knowledge of paralarvae lipid requirements and composition, growth and survival. To this purpose, the effects of feeding with Grapsus zoeae as sole prey were compared with Artemia at two different stages (nauplii and juveniles), which also differed in their lipid profiles. After 15 days of feeding, the best growth and survival of paralarvae was obtained in the Grapsus group, and no differences were observed between both Artemia groups. Triacylglycerides storage in paralarvae seemed to be co‐related with a lower growth and survival, but not with its prey levels. Contrarily, sterol ester levels were higher in paralarvae fed Grapsus, reflecting its content in the prey. The best paralarval viability was related to higher levels of 22:6n‐3 (DHA) and 20:4n‐6 (ARA), also reflecting its higher content in the prey. On the other hand, neither the 20:5n‐3 (EPA) levels in the prey nor in paralarvae were related to growth or survival. The implications of these results are discussed considering the lipid requirements of O. vulgaris paralarvae.     

Insecticide resistance in Bemisia tabaci (Homoptera: Aleyrodidae) populations from Crete

The resistance levels to alpha-cypermethrin, bifenthrin, pirimiphos-methyl, endosulfan and imidacloprid were determined in Bemisia tabaci (Gennadius) from Crete. Five B tabaci populations collected from greenhouse and outdoor crops were bioassayed and compared with a reference susceptible strain. Bemisia tabaci collected in a floriculture greenhouse exhibited the highest resistance against all insecticides: at LC50, resistance factors were 23-fold for bifenthrin, 80-fold for alpha-cypermethrin, 18-fold for pirimiphos-methyl, 58-fold for endosulfan and 730-fold for imidacloprid. A population collected on outdoor melons was more susceptible than the reference strain against all insecticides tested, suggesting the occurrence of local highly susceptible B tabaci populations in 'refugia'. In pairwise comparisons of resistance levels, correlation was observed between the LC50 values of the pyrethroid insecticides bifenthrin and alpha-cypermethrin.     

Mutations associated with pyrethroid resistance in the honey bee parasite Varroa destructor evolved as a series of parallel and sequential events

Journal of Pest Science - Managed honey bees have suffered severe seasonal losses for most of the past 30 years, while at the same time there is a growing need for food crop pollination....     

First report of grapevine leafroll-associated virus-3 on peony plants in Ukraine

Journal of Plant Diseases and Protection - In summer 2021, six varieties of peony plants exhibiting severe leaf rolling and deformation, as well as severe plant dwarfism and mosaics were observed...     

The effect of butorphanol on the incidence of dexmedetomidine‐induced emesis in cats

ObjectiveTo evaluate the antiemetic effect of butorphanol (BUT) when co-administered with dexmedetomidine (DEX) in cats.Study designDouble-blind, randomized controlled cross-over experimental study.AnimalsFourteen purpose-bred healthy Domestic Short Hair cats, seven females and seven males, aged median (range) 14–84 (78) months and weighing 1.7–5.5 (4.0) kg.MethodsEach cat received five different treatment protocols intramuscularly (IM): (A) 25 μg kg⁻¹ DEX; (B) 20 μg kg⁻¹ DEX and 0.2 mg kg⁻¹ BUT; (C) 20 μg kg⁻¹ DEX and 0.1 mg kg⁻¹ BUT; (D) 25 μg kg⁻¹ DEX and 0.2 mg kg⁻¹ BUT; and (E) 20 μg kg⁻¹ DEX. Episodes of emesis, incidence and severity of nausea, and time to lateral recumbency were recorded for a period of 8 minutes after treatment administration, and the sedation was scored at the end of this period. The Friedman test and the Cochran’s Q-test were used to analyse the data. Significance was evaluated at the 5% level.ResultsThe proportion of cats that vomited was significantly lower with the treatment protocols that included BUT (B, C and D) compared with the protocols that included only DEX (A and E). The proportion of cats that had nausea was significantly higher with the protocols that included only DEX (A and E) compared with protocols B and D. Time to lateral recumbency (p = 0.09) and sedation score (p = 0.07) was not statistically different between the treatment protocols.Conclusions and clinical relevanceButorphanol can be used to prevent emesis and reduce the incidence and the severity of nausea caused by DEX in cats. It seems that the combination of BUT and DEX is very useful not only when emesis could result in serious complications, but also to provide comfort and well-being in cats sedated for minor procedures.     

Impact of agricultural land use on distribution of microbial biomass and activity within soil aggregates

The presence of aggregates of various sizes in the soil is an important condition for soil carbon sequestration. In this system, microbial biomass is a key link. This work was devoted to the study of the influence of land use systems on the distribution of SOС, MB-SIR, microbial activity and eco-physiological indices (qCO₂, QR, MB-SIR/SOС and qCO₂/SOС) in relation to the size of soil aggregates. The distribution of SOС, MB-SIR and mineralization activity among the aggregates was heterogeneous. In the soil of crop rotation, high mineralization activity and MB-SIR were found in the aggregates 0.5–0.1 mm, in the monoculture soil in aggregates <0.1 mm and in the control soil in the aggregates 1–0.25 mm. There was a general trend towards a decrease in microbial activity, MB-SIR and SOС availability with an increase in aggregate size. In agricultural soils, microbial activity was determined by large aggregates (>5 mm), while in the control soil, by the aggregates 5–1 mm. Depending on the type of site and the size of aggregates, the differences in microbial metabolism were revealed. The qCO₂ and QR values decreased, and the MB-SIR/SOС and qCO₂/SOС increased in the series: control soil > crop rotation > monoculture. In the control soil, the values of the eco-physiological indices decreased with decreasing aggregate size. And vice versa, in agricultural soils, these parameters were the highest in the microaggregates (<0.25 mm). The monoculture soil, in contrast to the control soil and crop rotation soil, turned out to be more energy efficient.     

Pathogenicity of three entomopathogenic fungi on pupae and adults of the Mediterranean fruit fly, Ceratitis capitata (Diptera: Tephritidae)

The pathogenicity of local isolates of the entomopathogenic fungi (EPF) Beauveria bassiana (Balsamo) Vuillemin, Isaria fumosorosea (Wize) (formerly Paecilomyces fumosoroseus (Wise) Brown & Smith) and Metarhizium anisopliae (Metschnikoff) Sorokin (Ascomycota: Hypocreales) were evaluated under laboratory conditions against pupae and adults of Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) via different routes of exposure. Average mortality of pupae after immersing them into spore suspensions was in general low and ranged from 18.7 to 23.9 % depending on fungal species and dose applied. However, adults obtained from treated pupae appeared to have higher mortality rates compared to control with all fungi and doses tested. Adults’ average mortalities ranged from 41.9 to 88.0 % after exposing them to EPF either by feeding on a mixture of conidial suspension and artificial food or by bodily contact with conidia, depending on fungal species, dose and method of exposure. The proportion of cadavers, pupae or adults, that produced visible signs of mycosis ranged from 40.4 to 73.3 % with the exception of those that were exposed to M. anisopliae. In that case, none of the insects that died after exposure to conidia of M. anisopliae developed visible mycelium on their surface. Moreover, confining treated with untreated adults indicated horizontal conidial transmission in some cases. Our results indicate that EPF might be a promising biological control agent for the Mediterranean fruit fly and could be utilised with different modes of application: soil application against pupae and cover or bait sprays against adults.     

Interacting effects of cation saturation and drying, freezing, or aging on the extractability of nonylphenol and phenanthrene from a sandy soil

Purpose

The structure and properties of the soil organic matter and its interactions with solutes may be altered by changes in soil chemistry and by the aging of soil. The main objective of this study was to investigate the effect of long-term aging and cation saturation of soil on the extractability and degradability of two hydrophobic xenobiotics in soil. In addition, it was tested if drying or freezing of soils can accelerate the relevant aging processes.

Materials and methods

The sandy topsoil was treated by either 0.1?M NaCl, CaCl₂, AlCl₃ solutions or water and samples were sterilized by ??-radiation and spiked with ¹⁴C-labeled nonylphenol (NP) or phenanthrene (Phe) at 10???g?g^?1 of soil. Samples were then used in four parallel experimental setups: (1) 9?months of aging under sterile conditions, (2) inoculation by native original soil with further 7?months of aging (bioaging), (3) drying and wetting or (4) freezing and thawing of soils. After different time intervals, the extractability of xenobiotics with water, cyclodextrin, and ethanol was investigated.

Results and discussion

During 9?months of aging under sterile conditions a continuous decrease of NP and Phe extractability and an increase of the non-extractable fraction occurred. During the 7?months of biologically active aging, the mineralization of NP was lower than of Phe while more NP remained extractable than Phe. In comparison to the sterile aging, the bioaging led to a less formation of non-extractable residues of NP and Phe. The long-term sterile aging effects on NP-extractability were also achieved by short-term freezing and thawing of the soils, while aging of Phe was better mimicked by drying?Cwetting cycles. The effects of cation saturation of soils on xenobiotics extractability were less pronounced.

Conclusions

Sterile aging, bioaging, freezing, and thawing facilitate the formation of the non-extractable fraction of NP and Phe in the soils. Different cation treatments alter soil properties, but the effects on aging of NP and Phe in soils were negligible.