Reduction In Hatchability Research Articles

Assessment of sublethal effects of permethrin on adult life characteristics and resistance dynamics in Aedes albopictus (Diptera: Culicidae)

Mosquitoes are regularly exposed to adverse effects of insecticides employed in field during vector control campaigns. Its primary goal is to eliminate the vector population; nevertheless, this practise typically ignores the residual impacts and long-term repercussions on the remaining population. Here, the current study analysed how sublethal exposure of insecticides alter the life qualities, genotypic and biochemical characteristics of mosquitoes. The resistance ratio value in Laboratory Resistant (Lab-R) larvae increased 10 times (0.010 mg/l to 0.108 mg/l) compared to Laboratory Susceptible (LabS) larvae. It also revealed that the surviving mosquitoes had 50% reduction in hatchability but had longer larval and pupal periods (15 days and 2 days), respectively. The survival rates decrease in female by 2 days but increase in male by 7 days which is of concern and necessitates additional study. Moreover, major role of monooxygenase was confirmed behind resistance development which was further supported by piperonyl butoxide assay where reduction in Tolerance Ratio (TR50) by 12-fold occurred and gene expression profile also showed high expression level of CYP6P12 gene. In resistant strain, cuticular thickness increased by 1.23 times and alteration at codon 1532 (ATC to TTC) on VGSC gene leads to mutation I1532F. The data gleaned from our work highlights the threat of sublethal insecticides on vector control techniques and offers ample evidence that the larval selection alters adult life qualities, metabolic properties and transgenerational features which contributes to the damage caused by resistance.

Molecular characterization of chicken astrovirus and pathogenicity of a novel isolate in China.

As an enteric virus, chicken astrovirus has been related to various kinds of diseases in chickens, including white chick syndrome, runting-stunting syndrome, severe kidney disease, urate deposits and visceral gout, generating economic losses in the poultry industry globally. The complete ORF2 gene of 31 CAstV isolates in six provinces of China during 2020-2022 was characterized and analyzed with the purpose of better understanding the molecular epidemiology and genetic diversity of CAstV field isolates. Phylogenetic analysis which was based on the complete ORF2 (capsid) amino acid sequence of 31 CAstV isolates and 57 reference strains indicated that 2 isolates belonged to subgroup Ai, 10 isolates belonged to subgroup Bi, 3 isolates belonged to subgroup Bii, 5 isolates belonged to subgroup Biii, 7 isolates belonged to subgroup Biv, 3 isolates belonged to subgroup Bv, and one isolate (JS202103) belonged to a new B subgroup. In addition, the novel CAstV strain JS202103 was successfully isolated in vitro, and its whole genome shared 76.9-94.3% identity with the 29 CAstV reference strains. JS202103 caused hatchability reduction, dead embryos, kidney disease and visceral gout in chicken embryos. Moreover, this is the also the initial study focusing on diverse CAstV strains including subgroups Biii, Biv, and Bv circulate in China. The current work contributes to improving our understanding of CAstV isolates in China, and it will also provide references for developing efficient measures to control this virus.

Altitudinal variability in chemical profile and pesticidal properties of Zingiber roseum (Roxb.) Roscoe extracts

Plant extracts are considered as a promising alternative to chemical pest control agents. The chemistry of plant extracts varies with several environmental as well as geographical factors. Zingiber roseum (Roxb.) Roscoe also known as “Rosy Ginger” and “Jangli Adrak” is one of the most important aromatic and medicinal plant of family Zingiberaceae. The present study aimed to investigate the impact of altitude on the chemical composition, nematicidal and herbicidal activity of Z. roseum rhizome and seed extracts. The plants were collected from three different altitudes of Kumaun, Uttarakhand representing different environmental conditions. The extracts were prepared in acetone using cold percolation method. The compositional variation in chemical constituents of the extracts was determined by gas chromatography-mass spectrometry (GC–MS) analysis. The yield and chemical composition of extracts showed a significant altitudinal impact. Nematicidal activity of extracts was performed against Meloidogyneincognita. Results showed that the extracts exhibited significant nematode mortality irrespective of the altitudinal gradients. A significant correlation of altitudinal gradient was observed for the nematode egg hatchability reduction for the rhizome extracts. It was observed that plants growing at higher altitudes had better egg hatchability reduction (86.42 ± 2.30% at 1000 μg/mL after 96 h), compared with those growing at lower elevations. The herbicidal activity of rhizome and seed extracts was performed against radish and chicory seeds and the extracts showed different level of intensity of germination percentage, root and shoot length inhibition. In silico molecular docking was conducted to screen the nematicidal activity of major and potent compounds with the crystalline structure of Glutathione S-transferases (GSTs) of Caenorhabditis elegans and Wuchereria bancrofti, and Glutathione S-transferase-1 (GST-1) of M. incognita. Based on the current study, extract of Z. roseum may be regarded as potential nematicidal and herbicidal agents and may have potential application as botanicals.

Involvement of glyphosate in disruption of biotransformation P450 enzymes and hepatic lipid metabolism in chicken

The current study investigated the potentially harmful consequences of pure glyphosate or Roundup® on CYP family members and lipid metabolism in newly hatched chicks. On the sixth day, 225 fertilized eggs were randomly divided into three treatments: (1) the control group injected with deionized water, (2) the glyphosate group injected with 10 mg pure glyphosate/Kg egg mass and (3) the Roundup group injected 10 mg the active ingredient glyphosate in Roundup®/Kg egg. The results of the study revealed a reduction in hatchability in chicks treated with Roundup®. Moreover, change of Lipid concentration in serum and the liver-treated groups. Additionally, increased liver function enzymes and increased oxidative stress in the glyphosate and Roundup® groups. Furthermore, liver tissues showed histological changes and several lipid deposits in glyphosate-treated groups. Hepatic CYP1A2 and CYP1A4 expressions were significantly increased (p < .05) after glyphosate exposure, and suppression of CYP1C1 mRNA expression was significant (p < .05) after Roundup® exposure. The pro-inflammatory cytokines genes IFN-γ and IL-1β expression were significantly increased (p < .05) after Roundup® exposure. In addition, there were significant differences in the levels of expression genes which are related to lipid synthesis or catabolism in the liver. In conclusion, in ovo glyphosate exposure caused disruption of biotransformation, pro-inflammatory and lipid metabolism in chicks.

Bioaccumulation, metabolism and toxicological effects of chiral insecticide malathion and its metabolites in zebrafish (Danio rerio)

The bioaccumulation, metabolism, tissue-specific distribution and toxicity of the widely used organophosphorous pesticide malathion to zebrafish were investigated on an enantiomeric level for evaluating the environmental risks. The metabolites were also monitored and evaluated. Malathion was metabolized by zebrafish very fast with the half-life of 0.12 d and showed a middle accumulation capacity in zebrafish with bioaccumulation factor (BCF) of 12.9 after a 15-d exposure. Brain could enrich higher concentration of malathion than other tissues. The metabolites malaoxon, malathion/malaoxon monocarboxylic acid (DMA), malathion/malaoxon dicarboxylic acid (DCA), dimethylthiophosphate (DMTP) and dimethyldithiophosphate (DMDTP) were found, in which DMTP and DCA were in higher level, indicating the metabolism was mainly induced by carboxylesterase degradation. The accumulation of malathion and malaoxon was stereoselective in zebrafish tissues, exhibiting S-enantiomer preferentially enriched. The acute toxicity test showed rac-malathion was low toxic to zebrafish, which was 1.2 and 1.6 folds more toxic than S-malathion and R-malathion respectively. Malaoxon was highly toxic to zebrafish and approximately 32 times more toxic than malathion. The toxicity of other metabolites was lower than malathion. Malathion could cause an apparent developmental toxicity to zebrafish embryo, including bradycardia, hatchability reduction and deformity, and abnormal movement patterns in zebrafish larva. Chronic toxicity indicated that malathion and malaoxon induced oxidative damage and neurotoxicity in the liver, brain and gill of zebrafish, and malaoxon exhibited a relatively high injury to the zebrafish brain. The results can provide information for the comprehensive assessment of the potential risk of malathion to aquatic organisms and highlight the necessity of consideration of stereoselectivity and metabolites when systemically evaluating pesticides.

Impact of Different Ambient Temperatures on Egg-Laying and Hatching Parameters in Japanese Quail

The objective of this study was to determine the impact of different ambient temperatures on egg production and hatching parameters in Japanese quail. Sixteen weeks old male and female Japanese quail were assigned to 10 cages as 1 male and 5 females. Quails were housed in a poultry yard belonging to the Faculty of Agriculture. Quails were reared under 16 hours’ light and 8 hours’ dark photoperiod. During the study, water and food were freely available as ad-libitum. Regularly egging five layer cages were selected and their laying and hatching performances were compared for three weeks when there were highest differences in average room temperatures (22.38 ± 0.21; 23.10 ± 0.04 and 23.76 ± 0.18°C). Changes in weekly mean ambient temperatures did not affect egg weights, egg mass, weekly egg laid/hen, and weekly egg weight/hen. Fertility and hatching rates were also not significantly changed (P&amp;gt;0.05). Lower ambient temperature (22.38°C) caused a significant reduction in hatchability and increment in embryonic mortality as compared with the 23.10°C group. It is possible to postulate from the data presented here that the best room temperature for hatchability and lower embryonic mortality in Japanese quail, is around 23°C.

Hydoxylated β- and δ-Hexacholorocyclohexane metabolites infer influential intrinsic atomic pathways interaction to elicit oxidative stress-induced apoptosis for bio-toxicity

Hexachlorocyclohexane (HCH) has been recognized as an effective insecticide to protect crops against grasshoppers, cohort insects, rice insects, wireworms, and other agricultural pests and; for the control of vector-borne diseases such as malaria. It is a cyclic, saturated hydrocarbon, which primarily exists as five different stable isomers in the environment. Though the use of HCH is banned in most countries owing to its adverse effects on the environment, its metabolites still exist in soil and groundwater, because of its indiscriminate applications. In this study, a dose-dependent toxicity assay of the HCH isomers isolated from soil and water samples of different regions of Odisha, India was performed to assess the in vivo developmental effects and oxidative stress in zebrafish embryos. Toxicity analysis revealed a significant reduction in hatching and survivability rate along with morphological deformities (edema, tail malformations, spinal curvature) upon an increase in the concentration of HCH isomers; beta isomer exhibiting maximum toxicity (p < 0.05). Oxidative stress assay showed that ROS and apoptosis were highest in the fish exposed to β-2 and δ-2 isomers of HCH in comparison to the untreated one. Zebrafish proved to be a useful biological model to assess the biological effects of HCH isomers. In addition, the results suggest the implementation of precautionary measures to control the use of organochlorine compounds that can lead to a decrease in the HCH isomers in the field for a healthier environment.

Isolation, Identification, and Genomic Characterization of Chicken Astrovirus Isolates From China.

Chicken astrovirus (CAstV) infection can cause diarrhea, nephritis, stunted growth, and “white chickens” condition, resulting in economic losses to the poultry industry. Currently, a few CAstVs were isolated and a few full-length genome sequences of CAstV have been deposited in the GenBank. In the present study, two CAstV isolates (AAstV/Chicken/CHN/2017/NJ01 and AAstV/Chicken/CHN/2018/CZ01) were successfully isolated by using LMH cells, and we molecularly characterized these two CAstV isolates and observed the effect of these two isolates on hatchability using chicken embryo infection experiment. The genetic analysis demonstrated that these two strains had the typical characteristics of avian astroviruses, which were composed of three open reading frames, 5′UTR, and 3′UTR. The full-length genome sequence showed a high-degree identity at nucleotide level of 97.5–98.7% among Chinese isolates suggesting their common ancestors and limited sequence divergence. Sequence analysis of ORF2, which encodes the capsid protein associated with classification of avian astrovirus, revealed our two isolates belonging to CAstV Bi subtype. At the amino acid level, the complete capsid region of Chinese strains shared genetic distances of 0.03–0.04 with FP3 strains isolated from the UK, suggesting their common origin. Meanwhile, hatchability reduction was observed. These results provided novel insights into the molecular epidemiology and hatchability effect of CAstV.

Toxicidade in vitro da Niedenzuella (Tetrapterys) multiglandulosa em embriões bovinos

Abstract Niedenzuella (Tetrapterys) multiglandulosa, a vine plant found in Brazil, has been correlated to outbreaks of poisoning in cattle and buffaloes, generating economic losses related to the death due to heart failure, miscarriage, abortion, stillbirth, and neonatal mortality. The aim of this study was to examine the embryotoxic potential of the aqueous plant extract on in vitro bovine embryos. In vitro study was performed in five replicates of bovine embryo culture assigned in two groups: control, in vitro embryo culture medium without the aqueous plant extract; treated group, with addition of 2.7mg/mL of aqueous plant extract (10%) to the embryo culture on the sixth day of culture. Cleavage rate was evaluated at day 2 of the cell culture. Viability, hatchability and underdevelopment of blastocysts on the seventh, eighth, and ninth days (D7, D8, and D9, respectively) of culture were assessed under stereoscopic microscope. On day 7, blastocysts were submitted to TUNEL assay to determine apoptotic index. In vitro exposure of bovine embryos to of N. multiglandulosa resulted in reduced embryo development and survival, evaluated by dark cytoplasm indicating poor morphology and poor quality with marked reduction of hatchability. We observed a significant reduction of blastocyst production/number of cleaved embryos (60.6% vs 41.5%); reduction of blastocysts production/total number of matured bovine oocytes (35.1% vs 21.3%); and embryonic hatching rates (38.0% vs 10.0%). However, no effects were observed on the apoptotic rate. In conclusion, aqueous extract of N. multiglandulosa leaves reduces bovine embryo viability in vitro, suggesting possible detrimental effects on embryo development.

Egg inoculation of conjugated linoleic acid and lauric acid in meat quails

The objective of this study was to evaluate the effects of inoculation in egg with sources of conjugated linoleic acid (CLA) and lauric acid (LA) on hatchability, zootechnical performance and carcass characteristics of quails from one to 35 days of age. On the 7th day of incubation, the eggs were inoculated with 0.05 mL of the supplement according to the treatments, CLA and LA. After birth, the birds were housed in cages until 35 days. A completely randomized design was used, with six treatments and six replicates of 10 birds per cage. The inoculations in eggs with CLA and LA did not interfere in the performance and carcass characteristics of quails at 21 and 35 days of age. However, may be associated with a decrease in egg hatchability. The highest absolute weight of the gizzard was observed at 35 days, from birds inoculated in egg with CLA 240 mg and LA 60 mg in the incubation phase, in comparison to the other treatments. In conclusion, the reduction in hatchability makes it impossible to recommend the use of conjugated linoleic acid and lauric acid - in ovo.

Isolation and characterization of a novel chicken astrovirus in China

Chicken astrovirus (CAstV) is associated with kidney disease and visceral gout, runting and stunting syndrome, and white chick hatchery disease, causing economic losses to the poultry industry worldwide. In this study, 55.6% of 36 clinical samples from Guangdong province in China were positive for CAstV, but negative for other common enteric viruses, including avian nephritis virus, infectious bronchitis virus, fowl adenovirus Group I, Newcastle disease virus, chicken parvovirus, reovirus, and rotavirus by PCRs and RT-PCRs. A CAstV strain, named GD202013, was isolated from Guangdong province in south China, and was identified by CAstV RT-PCR. A whole genome sequence analysis demonstrated that GD202013 shares 76.0 to 88.1% identity with 24 reference strains in GenBank. Phylogenetic analysis, based on whole genome and capsid protein, showed that GD202013 is more closely related to 2 US strains (GA2011/US/2011 and 4175/US/2011) belonging to subgroup Bii. Recombination analysis indicated that GD202013 is a recombinant strain formed by 3 strains: a major parent strain CkP5/US/2016, and 2 minor parent strains (GA2011/US/2011 and G059/PL/2014). In addition, the chicken embryo infection experiment demonstrated that GD202013 causes hatchability reduction, growth depression, and death of embryos. Macroscopic and microscopic lesions in the liver, kidney and small intestine were observed in the dead-in-shell embryos. This is the first report of the novel CAstV infection in China.

Resting egg banks can facilitate recovery of zooplankton communities after short exposure to glyphosate.

We assessed the short-term viability and recovery of zooplankton communities after exposure to glyphosate (active ingredient-a.i.). We conducted a hatching experiment in two steps: Step 1-natural lake sediments containing resting egg banks were placed into individual trays and exposed to a solution medium of glyphosate at three different treatments (LD = Values below the detection limits, LD < 0.05, 0.44, and 0.89 mg a.i./L) for 14 days; and Step 2-we replaced the exposure solution of glyphosate with distilled freshwater, keeping them all trays under freshwater conditions for another 14 day. The results from Step 1 showed significant effects of glyphosate on the emergence patterns of resting eggs, with a reduction in hatching of rotifers, mainly at concentrations of 0.44 and 0.89 mg a.i./L. On the other hand, the results from Step 2 showed an increase in the emergence of viable eggs for rotifers after restoration of freshwater conditions in all treatments; there was no effect for total zooplankton and microcrustaceans. These findings suggest that (i) glyphosate may, effectively, impair zooplankton hatching from resting egg banks; (ii) the magnitude of the negative effects depends on the the zooplanktonic group considered; and (iii) the restoration of freshwater conditions may, in some way, allow the recovery of the zooplankton community from viable egg banks. Our results can be useful in predicting the influence of glyphosate on the distribution patterns of freshwater zooplankton, which can represent vital information for environmental managers.

Synthesis of Cordyceps fumosorosea-Biochar Nanoparticles and Their Effects on Growth and Survival of Bemisia tabaci (Gennadius)

Nanotechnology can offer an environmentally sustainable alternative to synthetic chemicals for pest management. Nano-formulations of different microbial pest control agents have been effective against several insect pests. Synthesis of Cordyceps fumosorosea-biochar (BC) nanoparticles and their bio-efficacy against Bemisia tabaci was observed during this study. The characterization of C. fumosorosea-BC nanoparticles through different analytical techniques showed successful synthesis of nanoparticles. UV spectroscopy showed a characteristic band of surface plasmon between 350 and 400 nm; SEM images confirmed the synthesis of spherical shaped nanoparticles; X-ray diffractogram showed strong peaks between 2θ values of 20°–25°; and atomic force microscopy (AFM) analysis revealed particle size of 49.151 nm. The bioassay studies demonstrated that different concentrations of C. fumosorosea-BC nanoparticles caused significant reduction in hatchability of B. tabaci eggs as well as survival of immatures emerging from treated eggs when compared with controls. The results also revealed that C. fumosorosea-BC nanoparticles were highly pathogenic against 2nd and 3rd instar nymphs and pupae of B. tabaci having LC50 values of 6.80, 7.45, and 8.64 ppm, respectively. The LT50 values for 20 ppm concentration of C. fumosorosea-BC nanoparticles against 2nd and 3rd instar nymphs, and pupae of B. tabaci were 3.25 ± 0.29, 3.69 ± 0.52, and 4.07 ± 0.51 days, respectively. These findings suggest that C. fumosorosea-BC nanoparticles can potentially be used in biorational B. tabaci management programs.

Comparison between Toxicoiogicai and Biological Efficiency of some Aromatic Oils and other Compoundes on Two Spotted Spider Mite

Control of the two spotted spider mite, Tetranychus urticae(Koch) using the conventional acaricides resulted in many problems . So, this study was carried out to evaluate the toxicity of certain alternative pesticides against this pest ,T. urticae as well as some biological aspects under laboratory conditions using two aromatic oils (Basil and Carnation) .one natural oil (Nat-1) and one conventional acaricide (Helbstar). The results indicated that Helbstar was the highest toxic compound to adult females of T. urticae followed by Nat-1 with Lc50 values of 1686.5 and 2861.5 ppm, respectively while Basil was the least toxic one with Lc50 value of 5990.4 ppm . The population showed more homogeneity in its response to the aromatic oils (Basil and carnation). Also, the results showed that the Helbstar caused the highest reduction in egg deposition with a mean number of 1.0 egg / day followed by Nat-1 with a mean number of 4.45 eggs / day , while Carnation was the lowest one with a mean number of 11.85 egg / day. The egg hatchability decreased with the increase of egg age at treatment by Basil , while in treating 1,2 and 3 day old eggs , the highest reduction in hatchability was found for Nat-1 , Helbstar and Carnation, with 100% reduction in hatchability at the three ages .Thus, the obtained results are of a great importance as they are taken into account in planning programs of integrated pest management.

The Isolation and Molecular Characterization of an Astrovirus From "Yellow" Chickens, China.

Chicken astrovirus (CAstV) infection is strongly associated with kidney disease, gout, “white chicks” hatchery disease, and runting and stunting syndrome (RSS). In the present study, 82.5% of 154 clinical samples from different provinces in China were positive for CAstV by RT-PCR. One CAstV isolate, designated as AAstV/Chicken/CHN/2017/NJ01, was successfully isolated from the small intestine of “Yellow” chickens using LMH cells. The genome sequence and structure analyses revealed that NJ1701 had the typical characteristics of avian astroviruses which was genetically distinct from other Avastrovirus. This isolate was classified as Group B subgroup i based on phylogenetic analysis of complete ORF2 (capsid) amino acid sequences. Meanwhile, growth depression and hatchability reduction were observed in the chicken embryo infection experiment. The results in the current study will contribute to our understanding of chicken astrovirus in China.

Effects of embryonic exposure to chromium (VI) on blood parameters and liver microstructure of 1-day-old chickens

Hexavalent chromium (Cr(VI)) has carcinogenic, nephrotoxic, hepatotoxic, and neurotoxic effects. Exposure to Cr(VI) can also lead to hematological alterations and blood biochemical changes. The literature on Cr(VI) toxicity concerns mostly adult forms of vertebrates. In this study, an attempt was made to determine the effect on the developing chicken embryo of Cr(VI) in ovo administration. It was observed that chromium affected the hatchability of chicks in a dose-dependent manner. At a dose from 25 to 250 μg per egg, Cr(VI) resulted in a statistically significant reduction of hatchability. Chromium administrated at lower doses (1.56 and 2.5 μg per egg) caused a statistically insignificant increase of hatchability. However, chromium at a level of LD50 (15.6 μg per egg) or 1/10 LD50 (1.56 per egg) did not cause major changes in hematological parameters or plasma biochemical indices in newly hatched chicks. The same doses did not lead to any histopathological changes in the liver.

Effectiveness of Some Plant Extracts against the Two-Spotted Spider Mites, Tetranychus urticae Koch Under Laboratory And Greenhouse Conditions (Acari: Tetranychidae).

The present study was carried out to investigate the effect of five plant extracts, Limoniastrum guyonianum Del., Zygophyllum album L., Calotropis procera (Ait.), Thymelaea hirsuta (L.) Endl and Dodonaea viscosa L. at the concentrations 0.01 and 0.005 %. The toxic effect of these concentrations was tested against adult females of the Two-spottedd spider mite Tetranychus urticae Koch (TSSM) 24, 48 and 72 h after treatment under laboratory conditions. The results showed that, after 72 h, the highest mortality 93.33% was recorded by treatment with seeds of C. procera followed by leaves of D. viscosa 86.67% at the concentration of 0.01%. At the concentration 0.005%, the highest mortality was 66.67% by C. procera (seed extract). Under greenhouse conditions, after 72 h at 0.01 % and 0.005 % concentrations were giving a highly percent reduction of hatchability for eggs at C. procera (seeds extract) with an average 95 % and 79.49 % respectively. Also, of larva stages was recorded highly percent mortality at 0.01% and 0.005 % concentration of C. procera (seeds extract) 91.67 % and 70% respectively. In nymphs, the highest mortality percentage with C. procera (seeds) at the same concentrations after 72 h were recorded 93.75% and 71.43 % respectively. In adult females was found the highest mortality percentage in C. procera (seeds extract) at 0.01% and 0.005 % concentration after 72 h was recorded 91.67% and 76.92 %. Analytical studies proved that major amounts of phenolic compounds were detected in T. hirsuta catechin, gallic and chlorogenic acids at the concentrations 1609.24, 1066.78 and 839.67 µg/g., respectively. In C. procera (seeds extract) it was found that phenolic compounds were lower than T. hirsuta, while coumaric acid has been only identified in C. procera seeds (21.08 µg/ g. plant). In D. viscosa, phenolic compounds were represented by chlorogenic acid (267.41 µg/ g plant) and gallic acid (84.43 µg/ g plant), while catechin was not detected. The highest mortality percentage of T. urticae treated with seeds extracts may be due to the appearance of coumaric acid, which was found in seeds more than other extracts.

Impact of long-term parental exposure to Tamiflu metabolites on the development medaka offspring (Oryzias latipes)

Despite the widespread use of the antiviral drug, Tamiflu®, little is known about the long-term toxic effects of drug or its metabolites in an aquatic ecosystem. This study integrated epidemiological and ecotoxicological methods to determine environmentally relevant concentrations of Tamiflu. A model based on the species medaka (Oryzias latipes) was then used to determine the health status and reproductivity of adults exposed to the drug as well as the embryonic development of offspring. The proposed ecotoxicological model was also used to quantitatively and qualitatively evaluate the toxicodynamic parameters related to egg production, hatchability, and development. Our results revealed that at an environmentally relevant exposure, Tamiflu and its metabolites had no adverse effects on growth, survival, or fecundity of adult medaka. Nonetheless, we observed a reduction in hatchability under exposure to 300 μg L−1 and a reduction in body length under exposure exceeding 90 μg L−1. Under exposure to 300 μg L−1, the estimated spawning time to reach 50% of the maximum percentage of cumulative egg production (ET50) far exceeded that of the control group (without exposure to Tamiflu). We also observed a ∼ 3-fold decrease in maximum egg hatching (Emax). Based on an integrated epidemiological and ecotoxicological model, predictions of environmental concentrations of Tamiflu and its metabolites revealed that the influenza subtypes associated with increases in environmental concentrations: A(H3N2) > A(H1N1) > type B (in order of their effects). We also determined that A(H3N2) posed a potential risk to hatchability and development. Note however, the environmental concentrations of Tamiflu and its metabolites in most countries are lower than the effect concentrations derived in this study, indicating no hazards for aquatic environments. We recommend the use of hatchability and embryonic development as indicators in assessing the effects of long-term parental exposure to Tamiflu metabolites.

Directed energy system technology for the control of soilborne fungal pathogens and plant-parasitic nematodes.

It is challenging to manage soilborne pathogens and plant-parasitic nematodes using sustainable practices. Here, we evaluated a novel energy application system, Directed Energy System (DES). This system generates pulses of energy capable of impacting selected biological organisms. The oomycete Phytophthora cinnamomi, the fungus Verticillium dahliae, and the plant-parasitic nematodes Meloidogyne hapla and Globodera ellingtonae were added to soil. Then DES-generated energy was applied to soil and impacts on target organisms were determined. DES applied at 20, 40 and 70 J cm-3 to P. cinnamomi and V. dahliae resulted in ≥50% and 92% reductions (respectively) of propagules per gram of soil in comparison to the untreated control. There was a significant reduction of M. hapla eggs per gram of host tomato root between the untreated control, and 2.2, 13 and 25 J cm-3 DES dosages applied pre- or post-planting. Additionally, an 84% reduction in hatch from G. ellingtonae encysted eggs after treatment with 70 J cm-3 DES was observed. The dosages ranged from 40 or 80V mm-1 for nematodes to 200 V mm-1 for fungi. DES-generated energy reduced survival of the soilborne pathogens P. cinnamomi and V. dahlia, and the plant-parasitic nematodes M. hapla and G. ellingtonae. The application of this technology to a field setting remains to be considered. Published 2020. This article is a U.S. Government work and is in the public domain in the USA. Pest Management Science published by Wiley Periodicals, Inc. on behalf of © 2020 Society of Chemical Industry.

Development of Copper Hatch Baskets and Evaluation of the Productive Indexes of a Commercial Hatchery

Background: The dissemination of pathogenic microorganisms in hatcheries leads to a higher number of contaminated eggs, causing reduction in hatchability and increase of discarded chicks. Sanitation programs are crucial for maximum hatchability and chick quality. Efforts have been made to find alternative approaches to the conventional disinfectants, and surfaces with copper, which have antimicrobial properties, could assist in this process. However, the possible adverse effects of copper surfaces on chicks in hatcheries have not yet been evaluated. The present study aimed at developing hatch baskets composed of copper and evaluating the effect of these baskets on the productive indexes of a hatchery.Materials, Methods and Results: For this experiment, 3.15 kg hatch tray prototypes with 99.9% Cu (Cu11000) were developed to fit inside conventional polypropylene hatch baskets (580 × 755 × 83 mm). Six polypropylene hatch baskets (control group) and 6 polypropylene hatch baskets covered by 99.9% copper (Cu11000) hatch trays (test group) were evaluated during 5 hatchings. Hatched eggs and chicks remained in contact with the hatch basket surfaces for at least 72 h, corresponding to the entire period in which they were located in the hatcher. Cleaning and disinfection programs of the hatchery were not modified. The level of microbial contamination on the hatch baskets was evaluated at 6 different periods: 0 h (initial contamination after disinfection and egg transfer to the trays); 24 h, 30 h, 45 h and 60 h after the first sampling; and at the moment when chicks were removed from the hatching cabinet and transferred to the chick-holding room (&gt; 60 h). Counting of total moulds and yeasts, mesophilic microorganisms, Enterobacteria and Escherichia coli colonies was performed. The number of hatched chicks, non-hatched eggs, and chicks discarded were registered for each hatching. Microbiologic analyses showed no growth on hatch baskets neither of the test group nor on those of the control group, regardless of the period evaluated. No significant difference was found between the two groups in the counts of hatched chicks, non-hatched eggs, and chicks discarded. Discussion: The antimicrobial efficacy of copper surfaces has been established for a variety of bacteria and fungi, including in the healthcare environment. In addition, antimicrobial resistance to copper is extremely rare because of copper’s multisite kill mechanism and other mostly nonspecific damage mechanisms. Several copper applications have been established; however, the potential adverse effects of using copper surfaces in hatcheries on chicks or on hatchery productive indexes had not yet been evaluated. The analyses performed in this study did not show microbiological growth. The results showed that the copper surface did not cause any significant adverse effects on chicks. The hatched chicks were visually healthy, and no significant difference was found between the numbers of chicks discarded in the control and test groups. Since the production parameters were not altered or impaired in the present study, it is possible to conclude that the use of copper surfaces in hatcheries can be an effective tool in the microbiological control of these environments. Nevertheless, copper alloys lend themselves to the creation of self-sanitizing surfaces that should be used as a complement and not as a substitute for standard cleaning and disinfection practices.