Domestic Strains Research Articles

Are Current Aspergillus sojae Strains Originated from a Native Aflatoxigenic Aspergillus Species Population Also Present in California?

Aspergillus sojae has long been considered a domesticated strain of Aspergillus parasiticus. This study delineated relationships among the two species and an Aspergillus PWE36 isolate. Of 25 examined clustered aflatoxin genes of PWE36, 20 gene sequences were identical to those of A. sojae, but all had variations to those of A. parasiticus. Additionally, PWE36 developmental genes of conidiation and sclerotial formation, overall, shared higher degrees of nucleotide sequence identity with A. sojae genes than with A. parasiticus genes. Examination of defective cyclopiazonic acid gene clusters revealed that the PWE36 deletion pattern was identical only to those of A. sojae. Using A. sojae SMF134 genome sequence as a reference, visualization of locally collinear blocks indicated that PWE36 shared higher genome sequence homologies with A. sojae than with A. parasiticus. Phylogenetic inference based on genome-wide single nucleotide polymorphisms (SNPs) and total SNP counts showed that A. sojae strains formed a monophyletic clade and were clonal. Two (Argentinian and Ugandan) A. parasiticus isolates but not including an Ethiopian isolate formed a monophyletic clade, which showed that A. parasiticus population is genetically diverse and distant to A. sojae. PWE36 and A. sojae shared a most recent common ancestor (MRCA). The estimated divergence time for PWE36 and A. sojae was about 0.4 mya. Unlike Aspergillus oryzae, another koji mold that includes genetically diverse populations, the findings that current A. sojae strains formed a monophyletic group and shared the MRCA with PWE36 allow A. sojae to be continuously treated as a species for food safety reasons.

Genetic variation for rectal gland volatiles among recently collected isofemale lines and a domesticated strain of Queensland fruit fly, Bactrocera tryoni (Diptera: Tephritidae).

Divergence between populations in mating behaviour can function as a potent premating isolating mechanism and promote speciation. However, very few cases of inherited intraspecific variation in sexual signalling have been reported in tephritid fruit flies, despite them being a highly speciose family. We tested for such variation in one tephritid, the Queensland fruit fly, Bactrocera tryoni (Qfly). Qfly mating behaviour depends on volatiles secreted from male rectal glands but no role for the volatiles from female rectal glands has yet been reported. We previously detected over 100 volatile compounds in male rectal glands and identified over 30 of them. Similar numbers were recorded in females. However, many compounds showed presence/absence differences between the sexes and many others showed quantitative differences between them. Here we report inherited variation among 24 Qfly lines (23 isofemale lines established from recent field collections and one domesticated line) in the abundance of three esters, two alcohols, two amides, an aldehyde and 18 unidentified volatiles in male rectal glands. We did not find any compounds in female rectal glands that varied significantly among the lines, although this may at least partly reflect lower female sample numbers. Most of the 26 male compounds that differed between lines were more abundant in the domesticated line than any of the recently established isofemale lines, which concurs with other evidence for changes in mating behaviour during domestication of this species. There were also large differences in several of the 26 compounds among the isofemale lines, and some of these differences were associated with the regions from which the lines were collected. While some of the variation in different compounds was correlated across lines, much of it was not, implicating involvement of multiple genes. Our findings parallel reports of geographic variation in other Qfly traits and point to inherited differences in reproductive physiology that could provide a basis for evolution of premating isolation between ecotypes.

Phenotype stability and dynamics of transposable elements in a strain of the microalga Tisochrysis lutea with improved lipid traits.

Microalgal domestication is an expanding research field that aims to multiply and accelerate the potential of microalgae for various biotechnological purposes. We investigated the stability of improved lipid traits and genetic changes of a domesticated strain of the haptophyte Tisochrysis lutea, TisoS2M2, previously obtained by a mutation-selection improvement program. After 7 years of maintenance, TisoS2M2 still displayed improved lipid traits compared with the native strain, demonstrating that a mutation-selection improvement program is suitable for obtaining a domesticated strain with stable, improved phenotype over time. We identified specific genetic variations between the native and domesticated strains and focused on the dynamics of transposable elements (TEs). DNA transposons mainly caused specific TE indels of the domesticated strain TisoS2M2, and some specific TE indels may have impacted genes associated to the neutral lipid pathway. We revealed transposition events for TEs in T. lutea and discussed on the potential role of the improvement program on their activity.

Factors influencing egg thiamine concentrations of Lake Ontario lake trout: 2019–2020

In the Great Lakes region, thiamine deficiency is considered a recruitment bottleneck for lake trout Salvelinus namaycush and has been correlated with the consumption of non-native alewife Alosa pseudoharengus. While alewife, the most abundant forage fish in Lake Ontario, are the predominant prey for lake trout, they also consume benthic prey such as round goby Neogobius melanostomus. Because variation in the proportion of alewife in lake trout diets is linked to variation in egg thiamine concentrations, understanding how factors such as region of capture and hatchery-strain of lake trout influence diet, are key to understanding the patterns of variation in egg thiamine concentrations observed in this species. With recent increases in natural recruitment of lake trout being observed in the western region of the lake, understanding if egg thiamine is a potential driver is crucial to the rehabilitation of lake trout. In this study, we evaluated egg thiamine concentrations in lake trout during 2019–2020. We found no significant difference in egg thiamine concentrations among regions. However, a stocked Lake Superior deepwater morphotype (Superior Klondike Wild – SKW) showed significantly higher egg thiamine concentrations compared to the lean morphotype including Seneca (SEN) and Lake Champlain Domestic (LCD) strains. An analysis of fatty acid signatures of each hatchery-strain suggested that the SKW strain consumed a higher proportion of round goby than lean strains. Overall, these results suggest that morphotypic differences in the feeding ecology of lake trout can result in biochemical changes which may influence the effectiveness of restoration efforts.

63 Echinococcosis in US patients: retrospective analysis of a neglected zoonosis with regional animal spillover risks

OBJECTIVES/GOALS: Our objective is to address the gaps in our epidemiologic understanding of Echinococcosis, a neglected and emergent zoonotic parasite in the US. Comparing regional differences in human cases with known Echinococcus genotypes in canine reservoirs will reveal landscape-level transmission risks. METHODS/STUDY POPULATION: Retrospective analysis of de-identified diagnosis codes for human echinococcosis in the US from 2002-2022 in a federal multi-healthcare network database (TriNetX). Analyses included Kaplan-Meier survival and specific parasite species cohort comparisons with descriptive summaries of demography and co-morbidities, and odds ratios for interventions (surgery, antiparasitics, cyst aspiration) and complications (anaphylaxis, sepsis, etc.) Mitochondrial genomes of Echinococcus spp. from next-generation sequencing ova-positive archival animal scat (National Park Service), along with sequences from published sources in the US, will be used to compare regional genotypic and reservoir host differences. RESULTS/ANTICIPATED RESULTS: Over 36,000 US patients were diagnosed with Echinococcosis in the past twenty years. Most cases had an unspecified parasite species, primarily affecting pediatrics (average age 16y +/- 10y) in the South/Southeast US, with very few interventions or medical complications reported. Patients with specific parasite species diagnoses (E. granulosus or E. multilocularis, N=500) had higher rates of mortality (11.7% at 10y), surgical (8.8%) and medical (18.2%) interventions, and complications (2%-17.2%), with demographic differences noted. Sequencing data and analysis pending for 47 Echinococcus positive wolf samples, with 78 additional sequences available for two types of Echinococcus spp. in wildlife, and lacking data for domestic dog-adapted strains in the US. DISCUSSION/SIGNIFICANCE: This study revealed a higher-than-expected burden of Echinococcosis in the US, confirming it is an under-recognized neglected and emergent disease. Future studies will address gaps regarding the origin of unspecified infections, with targeted surveillance of domestic dogs in high-risk areas.

Local characteristics of molecular epidemiolgy of Acinetobacter baumannii in Jilin province (northeast China)

A. Baumannii is an opportunistic nosocomial pathogen which has severe antibiotic resistance. However, the epidemiology is less clearly understood in Jilin province and China. Thus, 89 A. baumannii isolates from a single hospital in Jilin province between 2013–2017 were performed by MLST. In order to better understanding of the epidemiology of Jilin isolates, Chinese strains originated from other domestic regions and worldwide isolates in MLST database were analyzed by silico phylogenetic tools together. A total of 22 STs in Jilin were identified, and 10 STs were found to be novel. The top three predominant sequence types are ST195 (n = 34, 38.2%), ST208 (n = 14, 15.7%) and ST540 (n = 13, 14.6%). ST369 is predicted to be group founder and ST195, ST540 are subgroup founders of the majority STs in Jilin Province. Some newly discovered singletons showed close relationship with strains from other countries, which suggest that nation-cross transmission is one of important origin of Jilin strains. The majority of Jilin STs showed clonality and close relationship with the majorities from other regions of China. But occupation of individual STs in Jilin were different from that of other domestic regions. The aggregation trend and genetic relationship proved that predominant Jilin STs continue to mutate during transmission. Drug resistance facilitated transmission of Jilin A.baumannii isolates because more than 94% of isolates are resistant to at least one carbapenem and the STs with strong resistance to carbapenems usually has more isolates. In conclusion, high diversity and different occupation of STs, and occupation of novel STs proved that epidemiology of A. baumannii in Jilin has special regional characteristics, and drug resistance facilitated transmission of domestic strains and foreign strains.

CO2 gradient domestication improved high-concentration CO2 tolerance and photoautotrophic growth of Euglena gracilis

In order to improve CO2 biofixation efficiency of microalgae cultivated with coal-chemical flue gas, CO2 gradient domestication was employed to improve high-concentration CO2 tolerance and photoautotrophic growth of acid-tolerant Euglena gracilis. The dried biomass yield of photoautotrophic growth of E.gracilis increased from 1.09 g/L (wild-type strain) by 21 % to 1.32 g/L with CO2 gradient domestication to 15 % CO2. The RuBisCO activity and biomass production of E.gracilis strain domesticated to 99 % CO2 were 2.63 and 3.4 times higher, respectively, than those of wild-type strain. The chlorophyll a and b contents were 2.52 and 1.79 times higher, respectively, than those of wild-type strain. Superoxide dismutase and catalase activities of 99 % CO2-domesticated strain increased to 1.24 and 6 times, which reduced peroxide damage under high carbon stress and resulted in lower apoptotic and necrotic rates of domesticated strain. Thus, this work provides valuable guidance for CO2 fixation and adaptive evolution of E. gracilis in industrial flue gas.

Identification of a novel porcine Teschovirus 2 strain as causative agent of encephalomyelitis in suckling piglets with high mortality in China

BackgroundPorcine Teschovirus (PTV), also named Teschovirus A, is prevalent in pig populations, mainly causing neurological symptoms, diarrhea, pneumonia, and reproductive failure, however the morbidity and mortality are usually low in pig farms.Case presentationIn this study, we reported a PTV outbreak investigation in one large-scale pig farm in China with severe symptoms including diarrhea, lethargy, locomotor ataxia, nystagmus, paralysis of the hind limbs, and coma in piglets. More importantly, the mortality reached 38% in suckling pigs, which is remarkably high in PTV history. A novel PTV strain, named HeNZ1, was isolated from cerebral samples of one suckling pig and the genome sequence was obtained by NGS sequencing. Phylogenetic and evolutionary divergence analyses revealed that HeNZ1 belongs to PTV genotype 2. Surprisingly, the VP1 coding region of HeNZ1 shares the highest sequence similarity with European PTV-2 strains, instead of China domestic PTV-2 strains, implying it may not derive from China local PTV-2 strains. Multiple sequence alignment and B cell epitope prediction of PTV VP1 and VP2 protein revealed 10 B cell epitopes, 5 mutant clusters and 36 unique mutation sites, of which 19 unique mutation sites are located in B cell epitopes and exposed on the surface of VP1 or VP2, implying significant antigenic drift potential of HeNZ1.ConclusionThese results indicate that HeNZ1 is a highly virulent PTV-2 strain, which capable of causing severe neurological symptoms and high mortality in piglets. Bioinformatic analysis suggest that HeNZ1 is genetically and antigenically different from other Chinese PTV-2 strains. Overall, current case expanded our understanding of PTV-2 clinical spectrum and revealed the emergence of a highly virulent PTV-2 strain with substantial genetic diversity and antigenic drift potential in VP1 and VP2.

Changes in rotavirus epidemic strains

Rotavirus is a major cause of gastroenteritis in infants and is widely prevalent throughout the world regardless of the hygienic environment. However, it is not easy to understand the overall picture of rotavirus epidemic because of the great variety of genotypes and the large inter-seasonal and regional differences in the prevalent strains. Fortunately, the rotavirus vaccines now widely used around the world are highly effective and safe. The number of rotavirus gastroenteritis cases is declining dramatically, especially in high-income countries. In Japan, rotavirus vaccines have been included in the routine vaccination program since October 2020. Additionally, the impact of the SARS-CoV-2 pandemic control measures on the rotavirus epidemic was also very significant. These synergistic effects have resulted in few rotavirus outbreaks in recent years. Nevertheless, rotavirus is unlikely to be completely eradicated, and indeed a small number of sporadic cases continue to be reported. It will continue to be important to maintain high vaccination coverage and to continuously investigate prevalent strains. This review will provide an overview of the rotavirus epidemic situation in Japan and abroad. Annual changes in domestic epidemic strains that have been revealed by steady research to date will also be presented.

Non-classical digestive lipase BmTGL selected by gene amplification reduces the effects of mulberry inhibitor during silkworm domestication

Efficient utilization of dietary lipids is crucial for Bombyx mori, also known as domesticated silkworms. However, the effects of domestication on the genes encoding lipases remain unknown. In this study, we investigated the expression difference of one triacylglycerol lipase (BmTGL) between B.mori and wild (ancestor) silkworm strains (Bombyx mandarina). An immunofluorescence localization analysis showed that BmTGL was present in all parts of the gut and was released into the intestinal lumen. BmTGL expression was significantly enhanced in different domesticated silkworm strains compared to that in the B. mandarina strains. The BmTGL copy numbers in the genomes of the domesticated silkworm strains were 2-to-3 folds that of the B. mandarina strains and accounted for the enhanced expression of BmTGL in the domesticated silkworm strains. The Ser144Asn substitution in the Ser-Asp-His catalytic triads of BmTGL resulted in relatively lower lipase activity and reduced sensitivity to the lipase inhibitor morachalcone A. Moreover, BmTGL overexpression significantly increased the weights of the B. mori silkworms compared to those of the non-transgenic controls. Thus, the selection of BmTGL by gene amplification may be a trade-off between maintaining high enzymatic activity and reducing the effects of mulberry inhibitors during silkworm domestication.

Transcriptome Analysis Provides an Overview of Genes Involved in the Peculiar Food Preference at First-Feeding Stage in Mandarin Fish (Siniperca chuatsi)

The mandarin fish (Siniperca chuatsi) is an important economic fish species in China. Many carnivorous fish larvae feed on zooplankton or microdiets. However, the mandarin fish larvae feed on live prey fish exclusively, while refusing zooplankton or microdiets. A stable supply of palatable live prey fish results in high costs. Moreover, the application of live prey fish might bring the risk of pathogens. However, little is known about the genes underlying the food preference of mandarin fish larvae. Partial offspring of the domesticated strain could feed brine shrimp from three days post-hatching (dph), the open mouth day. In the present study, the mandarin fish larvae were randomly divided into three groups, then treated differently at 3 dph: (1) unfed; (2) fed with live prey fish; (3) fed with brine shrimp (Artemia). Differentially expressed genes were identified by RNA-seq. The differential expression of the transcription factors involved in retinal photoreceptor development and differentiation might contribute to the intake of brine shrimp in mandarin fish larvae. Meanwhile, the digestive enzyme genes involved in protein, fat, and carbohydrate digestion have been expressed in mandarin fish larvae at 3 dph, contributing to the digestion of ingested food. Our study provides an overview of genes and biological processes involved in the peculiar food preference at the first-feeding stage in mandarin fish larvae and has critical importance to the future application of non-fish live feeds in the culture of mandarin fish larvae.

Extracellular polymeric substances from soil-grown bacteria delay evaporative drying

When soils dry, water flow and nutrient diffusion cease as the hydraulic microenvironments vital for soil life become fragmented. To delay soil drying locally and related adverse effects, bacteria and plants modify their surroundings by releasing extracellular polymeric substances (EPS). As a result, the physical properties of hotspots like biological soil crusts or the rhizosphere differ from those of the surrounding bulk soil. Specifically, the presence of EPS delays evaporative soil drying. Despite the evidence of reduced evaporation from EPS-amended soils, the mechanisms controlling soil water content dynamics remain elusive. Thus, our study aimed to elucidate the potential of bacteria to modify their local environment when exposed to oscillations in soil water content induced by evaporative drying. We incubated sand microcosms with two contrasting strains of Bacillus subtilis for one week in a flow cabinet. At the end of the incubation period, local water loss was quantified and spatially resolved using time-series neutron radiography. Strain NCIB 3610, a complex biofilm producer steadily modified soil evaporation dynamics during the incubation period resulting in a substantial delay in soil drying due to hydraulic decoupling of the evaporation front from the soil surface. Evaporation dynamics remained largely unaltered in the microcosms inoculated with the domesticated strain 168 trp+ compared to the control treatment. The mechanism of hydraulic decoupling induced by NCIB 3610 was verified by estimates of diffusive fluxes and the position of the evaporation plane in the microcosm. Additionally, the role of polymeric substances in hydraulic decoupling was confirmed by an evaporation experiment using xanthan as an EPS analogue.

Biological properties of domestic strain vRub-Ant of rubella virus

Introduction. Rubella is a mild infectious disease affecting mainly children and is caused by the rubella virus, part of the Matonoviridae family, genus Rubivirus. Rubella causes congenital rubella syndrome (CRS) and is the main cause of developmental abnormalities, especially blindness and deafness.
 There is no specific treatment for rubella and CRS. In order to avoid possible complications from rubella infection, a live attenuated rubella vaccine based on the foreign strain of Wistar RA 27/3 rubella virus is used. However, the actual, more effective and preferred vaccine strain the rubella virus for the Russian Federation is considered to be a viral strain of rubella circulating on its territory.
 The aim of the study was to study the biological properties of the developed domestic cold-adapted strain vRub-Ant circulating in the territory of the Russian Federation.
 Materials and methods. Following cell cultures were used in the study human embryo lung diploid cell strain LECH-3, transferable cell line from embryonic kidney cells of green monkeys Vero CCL-81 and Vero ECC, human mesenchymal stem cells, human peripheral blood mononuclear cells (PBMC). Cell cultures were grown on a DMEM/F12 nutrient medium with the addition of 5% fetal bovine serum. Swabs from the pharynx and nasal passages from a child with rubella were used as clinical virus-containing material. Monoclonal anti-idiotypic antibodies m(anti-ID)Ab were used to assess the expression level of alpha/beta and gamma interferon receptors (/ and IFN-R)Ab, imitating the biological effects of alpha/beta and gamma interferons (/ and IFN) of humans. The cultural, virological, immunochemical and serological research methods were applied in the study.
 Results. Attenuation of the vRub-Ant clinical isolate of rubella virus was carried out for 20 consecutive passages on LECH-3 diploid cells at a reduced temperature of 30C. The main biological markers of attenuation were determined to be ts and ca phenotypes. The avirulence of the attenuated viral strain (att-phenotype) was assessed by the level of expression of / and IFN-R. A lower level of / and IFN-R expression was found on the membranes of human PBMC induced by the vaccine strain vRub-Ant in comparison with the parent wild variant of the rubella virus. This trait,the att phenotype, is characteristic of attenuated viral strains. It has been shown that the vaccine strain vRub-Ant has lost neurotropism and was unable to bind to the membrane receptors of the brain (MRB) of guinea pig embryos, unlike its parent rubella virus strain. The high immunogenicity of the domestic cold-adapted strain vRub-Ant was confirmed by high titers of neutralizing rubella antibodies observed in guinea pigs immunized subcutaneously with one vaccination dose of the virus.
 Conclusion. A domestic attenuated vaccine strain vRub-Ant of the rubella virus that has the main biological markers of attenuation (ts-ca and att phenotypes) has been developed. The vaccine strain vRub-Ant induces a high levels of neutralizing antibodies in guinea pigs following the immunization with a single vaccination dose of the vaccine. The viral strain vRub-Ant has lost its tropism to the MRB of guinea pig embryos, unlike its parent variant.

A novel method of domestication combined with ARTP to improve the reduction ability of Bacillus velezensis to Cr(VI)

In this study, the Cr(VI)-resistant bacterium LYB-23 was isolated from waste chromium residues in Sichuan and identified as Bacillus velezensis. The chromium tolerance of LYB-23 was improved by domestication (continuously increasing the chromium concentration in the medium from 60 to 200 mg/L). Subsequently, we screened a mutant strain, B. velezensis SA-23, using atmospheric pressure room temperature plasma (ARTP) mutagenesis for 90 s based on the domesticated strain. The minimum inhibitory concentration of B. velezensis on chromium increased from 80 mg/L for the original strain to 200 mg/L for the domesticated strain and to 400 mg/L for the mutant strain. The Cr(VI) reduction experiment results show that SA-23 can completely reduce 100 mg/L Cr(VI) within 24 h, and the reduction rate of 200 mg/L Cr(VI) reached 78.45% within 72 h. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analysis showed that ARTP mutagenesis did not change the type of functional groups on the surface of bacteria after reductive adsorption of Cr(VI) and the crystalline state of Cr(III); however, mutagenesis changed the biological morphology of bacteria and greatly enhanced the role of phosphate groups in the process of adsorption and reduction of Cr(VI). This experiment for the first time used the combined domestication and ARTP mutagenesis to effectively improve the tolerance of bacteria to Cr(VI) and their reduction adsorption efficiency, which proved to be an efficient method for the breeding of environmental remediation engineering bacteria and for promoting the application of microbial remediation.

Survival Model of Thoracic Contusion Spinal Cord Injury in the Domestic Pig.

Spinal cord injury (SCI) frequently results in motor, sensory, and autonomic dysfunction for which there is currently no cure. Recent pre-clinical and clinical research has led to promising advances in treatment; however, therapeutics indicating promise in rodents have not translated successfully in human trials, likely due, in part, to gross anatomical and physiological differences between the species. Therefore, large animal models of SCI may facilitate the study of secondary injury processes that are influenced by scale, and may assist the translation of potential therapeutic interventions. The aim of this study was to characterize two severities of thoracic contusion SCI in female domestic pigs, measuring motor function and spinal cord lesion characteristics, over 2 weeks post-SCI. A custom-instrumented weight-drop injury device was used to release a 50 g impactor from 10 cm (n = 3) or 20 cm (n = 7) onto the exposed dura, to induce a contusion at the T10 thoracic spinal level. Hind limb motor function was assessed at 8 and 13 days post-SCI using a 10-point scale. Volume and extent of lesion-associated signal hyperintensity in T2-weighted magnetic resonance (MR) images were assessed at 3, 7, and 14 days post-injury. Animals were transcardially perfused at 14 days post-SCI and spinal cord tissue was harvested for histological analysis. Bowel function was retained in all animals and transient urinary retention occurred in one animal after catheter removal. All animals displayed hind limb motor deficits. Animals in the 10-cm group demonstrated some stepping and weight-bearing and scored a median 2-3 points higher on the 10-point motor function scale at 8 and 13 days post-SCI, than did the 20-cm group. Histological lesion volume was 20% greater, and 30% less white matter was spared, in the 20-cm group than in the 10-cm group. The MR signal hyperintensity in the 20-cm injury group had a median cranial-caudal extent approximately 1.5 times greater than the 10-cm injury group at all three time-points, and median volumes 1.8, 2.5, and 4.5 times greater at day 3, 7, and 14 post-injury, respectively. Regional differences in axonal injury were observed between groups, with amyloid precursor protein immunoreactivity greatest in the 20-cm group in spinal cord sections adjacent to the injury epicenter. This study demonstrated graded injuries in a domestic pig strain, with outcome measures comparable to miniature pig models of contusion SCI. The model provides a vehicle for the study of SCI and potential treatments, particularly where miniature pig strains are not available and/or where small animal models are not appropriate for the research question.

Genotyping and Identification of Antigen B Gene Polymorphism of Echinococcus granulosus in Edirne, Thrace, and the First Report of Genotype G2 (Tasmanian Sheep Strain) in Turkey

Echinococcus granulosus is the causative agent of cystic echinococcosis in humans and livestock. It is common worldwide. Cystic echinococcosis is still an important public health problem in Turkey, which is an endemic region. To genotype Echinococcus granulosus isolates and investigate antigen B gene polymorphism in Thrace, Turkey. A cross-sectional study. Seventy-five hydatid cyst materials obtained between June 2020 and May 2021 were included in the study. Hydatid cyst materials were collected from 12 humans from various hospitals in Edirne and 63 from slaughterhouse animals during the same period. Cyst materials were localized in 8 livers and 4 lungs in humans, 23 livers and 17 lungs in cattle, and 13 livers and 10 lungs in sheep. In the first step, the 12S ribosomal RNA gene was amplified by polymerase chain reaction for all samples and run on an agarose gel. Band patterns were used for strain typing. Then, the selected samples that represented each of the band patterns obtained by single-strand conformation polymorphism analysis were sequenced for AgB1, AgB2, mt-CO1, and mt-ND1 genes. Three different genotypes in Edirne, Thrace, Turkey, were observed for Echinococcus granulosus: G1 (domestic sheep strain), G2 (Tasmanian sheep strain), and G3 (buffalo strain). G1 was the dominant genotype in Edirne, and G3 was the second most common. Additionally, polymorphism in AgB1 and AgB2 gene regions was found. This study is the first to report on Echinococcus granulosus G2 (Tasmania sheep strain) in Turkey and G3 (buffalo strain) and antigen B polymorphism in Thrace. The study results will contribute to the prevention and control programs for cystic echinococcosis in Turkey and worldwide.

Investigating the individual difference in distance calls of Bengalese finches using acoustic analysis

Most songbirds are monogamous and exhibit biparental care. They socially interact with other individuals, including those outside the family, through auditory modality. The capacity to explicitly identify conspecific individuals via acoustic cues enables fast turn-taking communication in a crowd, especially when visual signals are not available. Bengalese finches (Lonchura striata var. domestica) are domesticated strains of the white-rumped munia imported from China to Japan about 260 years ago. Previous studies have reported distance calls, which are emitted when a bird is visually separated from its conspecifics, are sexually dimorphic (both acoustically and perceptually) in Bengalese finches. However, the individuality in distance calls has not been thoroughly discussed yet. In this research, we recorded vocalizations from four pairs of Bengalese finches in kinship. To extract distance calls from those recordings, we use the Harmonics-to-Noise Ratio (HNR) to detect and remove noise, which mainly consists of aperiodic components. By analyzing acoustic features such as length, bandwidth, and peak frequency, we found that calls from the same individuals form clear clusters, and the difference between other individuals was more pronounced in contrast to kins. [Work supported by MEXT/JSPS grant #4903, 17H06380.]

Identification of domestic reservoirs and common exposures in an emerging lineage of Shiga toxin-producing Escherichia coli O157:H7 in England: a genomic epidemiological analysis

The zoonotic pathogen Shiga toxin-producing Escherichia coli (STEC) O157:H7 emerged during the 1980s as a causative agent of foodborne outbreaks associated with haemorrhagic colitis and haemolytic uraemic syndrome, which can be fatal. We investigated the emerging lineage IIc that was causing outbreaks of STEC O157:H7, identified and quantified the domestic and non-domestic reservoirs, and quantified patient exposures across the population of England. In this genomic epidemiological analysis study, all human STEC O157:H7 lineage IIc (n=925) isolates cultured from faecal specimens submitted to the UK Health Security Agency between June 1, 2015, and Dec 31, 2020, from patients in England in the community or in hospital, were whole-genome sequenced and the genomic population structure was described. Explanatory variables were obtained from microbiological surveillance data and STEC Enhanced Surveillance Questionnaire responses. Ancestral-state reconstruction using patient travel information was used to define domestic and non-domestic clades and transmission dynamics. Exposures for patients infected with isolates from domestic clades were assessed using mixed-effects multinomial univariable and multivariable regression. Lineage IIc emerged 50 years ago, and subsequent clonal expansions have resolved into six major extant clades. We defined two English domestic clades that emerged during the past 30 years, and four non-domestic clades comprising isolates that infected or were transmitted to patients in England via international travel or the consumption or handling of imported food. Throughout the study period, non-domestic clades contributed approximately twice the number of infections as domestic clades did. Patients infected with domestic IIc clade strains reported more frequent exposure to fresh produce (raw vegetables p=0·012; prepackaged salad p=0·0009), contact with animals (cattle p=0·021), and visits to farms (p=0·0053) than patients infected with strains from other STEC O157:H7 lineages. A multivariable mixed-effects multinomial model confirmed that within the domestic clades, the major risk factors for infection were prepackaged salad (clade 2.3.3, relative risk ratio [RRR] 1·72, 95% CI 1·09-2·72; p=0·019) and visits to farms (clade 2.5.2, RRR 1·98, 1·12-3·52; p=0·020) as fixed effects. Local authority district as a random variable had a strong but variable effect for clades 2.3.3 and 2.5.2. Lineage IIc has emerged as the most prevalent lineage of STEC O157:H7 in England, with a sizeable domestic reservoir. Human infection is associated with the consumption of contaminated fresh produce and contact with domestic livestock. The collection of routine, detailed exposure data on patients who are infected, integrated with high-resolution microbiological typing, enables powerful reframing of our understanding of foodborne disease risk within a One Health context. National Institute for Health and Care Research Health and UK Health Security Agency.

The potential use of Artemia for larval rearing of mandarin fish (Siniperca chuatsi)

The purpose of this study is to compare the effects of three live feeds for the larvae of the domesticated strain of mandarin fish (Siniperca chuatsi). Larvae of this strain of mandarin fish with salinity activation ingested Artemia nauplii was firstly observed. The larvae at 3 days post hatch (dph) were reared from first feeding to 9 dph and fed on starving (no food supplied), zebrafish (Danio rerio) (newly hatched larvae), Artemia nauplii and Daphnia magna, respectively. The results showed that the highest survival was found in the newly hatched larvae group (41.7 ± 1.5 %), and the lowest growth was found in the Daphnia group, respectively. A high food intake was found in the Artemia nauplii group, and the npy expression between the Artemia nauplii and newly hatched larvae groups had no significant difference (p＞0.05), whereas they were significantly lower than that of the starving group (p＜0.05). At the first feeding day, the activities of amylase, lipase and trypsin and the target of rapamycin (tor) expression in the Artemia nauplii and newly hatched larvae groups were significantly higher than those of the starving group. These results suggested that larvae of this strain of mandarin fish could feed on the newly hatched larvae and Artemia nauplii, and both of them could be digested, but the digestion might be insufficient in the Artemia nauplii group. Together, this study indicates that larvae of this strain of mandarin fish can ingest and digest Artemia nauplii during first-feeding.

Optimization of hazelnut husk medium for pullulan production by a domestic A. pullulans strain

Hazelnut husk is one of the most abundant agricultural residue in Turkey. Valorization of this lignocellulosic biomass would provide a promoting alternative for economical production of pullulan. In this study, dried hazelnut husk hydrolysate was used directly as fermentation medium for pullulan production by a domestic strain of Aureobasidium pullulans. The aim of this work was the optimization of some fermentation medium parameters by central composite design using response surface methodology (RSM). The effects of (NH4)2SO4 concentration, the volume of concentrated H2SO4 and the amount of ground hazelnut husk on pullulan production were optimized by RSM. The optimum levels of the fermentation parameters defined as 7.2 gL−1, 2.5 mL and 20 g, respectively. The maximum pullulan and exopolysaccharide concentrations were determined as 74.39 and 75.95 gL−1 , respectively in the optimum conditions. Specific growth rate of the strain was found as 0.097 h−1. FTIR spectral attributes confirmed the structure of pullulan. Thermal decomposition temperature of synthesized pullulan was found as 247.15 °C. This study showed that hazelnut husk was one of the novel substrate for production of the pullulan by A. pullulans AZ-6. No previous work was found to utilize dried hazelnut husk as fermentation medium for pullulan production by A. pullulans.