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Colonization and maintenance of mosquitoes in the laboratory is required to study physiology, ecology, and behavior of mosquitoes and interactions between mosquito and pathogens. Artificial blood feeding systems have been widely used to maintain the laboratory colony of Aedes albopictus. In this study, we investigated the effects of mating period (1, 3, 6, and 10 days) and time‐of‐day for bloodmeal (08:00, 13:00, and 18:00) in the use of an artificial feeding system on blood‐feeding rate, female fecundity, egg hatching rate, and developmental time of the Asian tiger mosquito, A. albopictus. Younger females mated for three or fewer days reproduced more eggs compared to those of oldest females mated for ten days. Similar to the result for eggs laid, the mean egg‐hatching rate was significantly higher from the offspring of younger females than from those of older females. However, mating period and time‐of‐day for bloodmeal had no effect on the blood feeding rate and developmental time. Taken together, we suggest that three‐day mating with bloodmeal at 18:00 is optimal for maintaining colonies of A. albopictus in laboratory conditions.

Insect ecdysis behavior, shedding off the old cuticle, is under the control of specific neuropeptides with the top command by the ecdysis triggering hormone (ETH). We characterized the ETH receptor (ETHR) of the malaria mosquito, Anopheles gambiae, by manual annotation of the NCBI gene (AGAP002881) and functional analysis, using a heterologous expression system in a mammalian cell line. The two splicing variants of ETHRs, ecdysis triggering hormone receptors (AgETHR-A and AgETHR-B), a conserved feature among insects, included of four (552 aa) and five exons (635 aa), respectively. The main feature of manual annotation of the receptor was a correction of N-terminal and exon-intron boundaries of an annotated gene (AGAP002881). Interestingly, the functional expression of the receptor in Chinese hamster ovary cells required modification of the transcription initiation site for mammalian Kozak consensus. In the calcium mobilization assay using the heterologous expression of each receptor, AgETHR-B showed a higher sensitivity to AgETH-1 (28 times) and AgETH-2 (320 times) than AgETHR-A. The AgETHRs showed specificity only to the ETH group of peptides but not to other groups carrying the C-termini motifs as PRXamide, such as pyrokinin1/DH and pyrokinin2/PBAN. Ecdysis triggering hormone receptors (AgETHR-B) responded to different ETH variants of other insect species more promiscuously than AgETHR-A.

Factors related to increasing globalization and climate change have contributed to the simultaneous increase and spread of arboviral diseases. Co-circulation of multiple arboviruses in the same geographic regions provides impetus to study the impacts of multiple arbovirus infections in a single vector. In the present study we describe co-infection and super-infection with Mayaro virus (Family Togaviridae, genus Alphavirus) and Zika virus (family Flaviviridae, genus Flavivirus) in vertebrate cells, mosquito cells, and Aedes aegypti mosquitoes to understand the interaction dynamics of these pathogens and effects on viral infection, dissemination and transmission. In Aedes aegypti mosquitoes, co-infection has a negative impact on infection and dissemination rates for Zika virus, but not Mayaro virus, when compared to single infection scenarios, and super-infection of Mayaro virus with a previous Zika virus infection resulted in increased Mayaro virus infection rates. We found that co-infection and super-infection negatively affected Zika viral replication in vertebrate cells (Vero and Huh), resulting in the complete blockage of Zika virus replication in some scenarios. At the cellular level, we demonstrate that single vertebrate and insect cells can be simultaneously infected with Zika and Mayaro viruses. This study highlights the dynamics of arboviral co- and super-infections and emphasizes the importance of considering these dynamics during risk assessment in epidemic areas.

Summary Herbivore‐induced plant volatiles (HIPVs) are widely recognized as an ecologically important defensive response of plants against herbivory. Although the induction of this ‘cry for help’ has been well documented, only a few studies have investigated the inhibition of HIPVs by herbivores and little is known about whether herbivores have evolved mechanisms to inhibit the release of HIPVs.To examine the role of herbivore effectors in modulating HIPVs and stomatal dynamics, we conducted series of experiments combining pharmacological, surgical, genetic (CRISPR‐Cas9) and chemical (GC‐MS analysis) approaches.We show that the salivary enzyme, glucose oxidase (GOX), secreted by the caterpillar Helicoverpa zea on leaves, causes stomatal closure in tomato (Solanum lycopersicum) within 5 min, and in both tomato and soybean (Glycine max) for at least 48 h. GOX also inhibits the emission of several HIPVs during feeding by H. zea, including (Z)‐3‐hexenol, (Z)‐jasmone and (Z)‐3‐hexenyl acetate, which are important airborne signals in plant defenses.Our findings highlight a potential adaptive strategy where an insect herbivore inhibits plant airborne defenses during feeding by exploiting the association between stomatal dynamics and HIPV emission.

In the postgenomics era, comparative genomics have advanced the understanding of evolutionary processes of neuropeptidergic signaling systems. The evolutionary origin of many neuropeptidergic signaling systems can be traced date back to early metazoan evolution based on the conserved sequences. Insect parathyroid hormone receptor (iPTHR) was previously described as an ortholog of vertebrate PTHR that has a well-known function in controlling bone remodeling. However, there was no sequence homologous to PTH sequence in insect genomes, leaving the iPTHR as an orphan receptor. Here, we identified the authentic ligand insect PTH (iPTH) for the iPTHR. The taxonomic distribution of iPTHR, which is lacking in Diptera and Lepidoptera, provided a lead for identifying the authentic ligand. We found that a previously described orphan ligand known as PXXXamide (where X is any amino acid) described in the cuttlefish Sepia officinalis has a similar taxonomic distribution pattern as iPTHR. Tests of this peptide, iPTH, in functional reporter assays confirmed the interaction of the ligand-receptor pair. Study of a model beetle, Tribolium castaneum, was used to investigate the function of the iPTH signaling system by RNA interference followed by RNA sequencing and phenotyping. The results suggested that the iPTH system is likely involved in the regulation of cuticle formation that culminates with a phenotype of defects in wing exoskeleton maturation at the time of adult eclosion. Moreover, RNAi of iPTHRs also led to significant reductions in egg numbers and hatching rates after parental RNAi., Author summary Vertebrate parathyroid hormone (PTH) and its receptors have been extensively studied with respect to their function in bone remodeling and calcium metabolism. Insect parathyroid hormone receptors (iPTHRs) have been previously described as counterparts of vertebrate PTHRs, however, they are still orphan receptors for which the authentic ligands and biological functions remain unknown. We describe an insect form of parathyroid hormone (iPTH) by analyzing its interactions with iPTHRs. Identification of this new insect peptidergic system proved that the PTH system is an ancestral signaling system dating back to the evolutionary time before the divergence of protostomes and deuterostomes. We also investigated the functions of the iPTH system in a model beetle Tribolium castaneum by using RNA interference. RNA interference of iPTHR resulted in defects in wing exoskeleton maturation and fecundity. Based on the differential gene expression patterns and the phenotype induced by RNAi, we propose that the iPTH system is likely involved in the regulation of exoskeletal cuticle formation and fecundity in insects.

Despite their capacity to acquire and pass on an array of debilitating pathogens, research on ticks has lagged behind other arthropod vectors, such as mosquitoes, largely because of a lack of genetic and molecular tools. CRISPR-Cas9 is transforming non-model organism research; however, successful gene editing has not yet been reported in ticks. Technical challenges for injecting tick embryos to attempt gene editing have further slowed research progress. Herein we report a successful tick embryo injection protocol for the black-legged tick, Ixodes scapularis, the first for any chelicerate species, and the use of this protocol for genome editing with CRISPR-Cas9. We also demonstrated for the first time that the ReMOT Control technique can be successfully used to generate genome mutations outside Insecta. Our results provide innovative tools to the tick research community that are essential for advancing our understanding of the molecular mechanisms governing pathogen transmission by tick vectors as well as for understanding the underlying biology of host-vector-pathogen interactions.

Understanding salivation in hematophagous arthropod vectors is crucial to developing novel methods to prevent vector-borne disease transmission. The interactions between the tick, host, and pathogens during salivation are highly complex, and are dynamically regulated by the tick central nervous system (synganglion). Recently, tick salivary modulation via neuropeptides was highlighted by mapping neuropeptidergic cells in the synganglion and salivary glands in hard ticks. In this study, we characterized the role of a novel neuropeptide, elevenin (IsElev), and its receptors (IsElevR1 and IsElevR2) in the innervation of the salivary glands from Ixodes scapularis female ticks. Homology-based BLAST searches of the I. scapularis genome and Sequence Read Archive (SRA), followed by gene cloning, identified candidate genes: IsElev, IsElevR1, and IsElevR2. The IsElev candidate contained common elevenin features: a signal peptide immediately before an elevenin precursor and two cysteines. During functional assays, synthetic IsElev efficiently activated both IsElevR1 and IsElevR2, as indicated by elevated calcium mobilization. IsElevR1 (EC50: 0.01 nM) was about 560 times more sensitive to synthetic IsElev than IsElevR2 (EC50: 5.59 nM). Immunoreactivity (IR) for IsElev and IsElevR1 was detected as a complex neuronal projection and several neurons in the synganglion. In salivary glands, IsElev-IR was detected in an axonal projection on the surface of the main salivary duct and in axon terminals within type II/III salivary gland acini, which are colocalized with SIFamide-IR. IsElevR1-IR was detected on the luminal surface of both type II/III acini. IsElev transcript levels were high in the synganglion and reached a peak at day 5 post-blood feeding. Salivary glands expressed IsElevR1, which gradually increased over the course of blood feeding until repletion. Here, we propose that IsElev and IsElevR1, localized in salivary gland acini types II/III, are likely involved in tick salivary secretion in the rapid engorgement phase of tick feeding. In addition, we also provide the evidences for IsElev action on the ovary by showing IsElevR1-IR and IsElevR2-IR on the surface of ovary.

Cas9-mediated gene editing is a powerful tool for addressing research questions in arthropods. Current approaches rely upon delivering Cas9 ribonucleoprotein (RNP) complex by embryonic microinjection, which is challenging, is limited to a small number of species, and is inefficient even in optimized taxa. Here we develop a technology termed Receptor-Mediated Ovary Transduction of Cargo (ReMOT Control) to deliver Cas9 RNP to the arthropod germline by injection into adult female mosquitoes. We identify a peptide (P2C) that mediates transduction of Cas9 RNP from the female hemolymph to the developing mosquito oocytes, resulting in heritable gene editing of the offspring with efficiency as high as 0.3 mutants per injected mosquito. We demonstrate that P2C functions in six mosquito species. Identification of taxa-specific ovary-specific ligand–receptor pairs may further extend the use of ReMOT Control for gene editing in novel species., Delivery of Cas9 ribonucleoprotein complexes can be done via microinjection into eggs, though this is a technically challenging procedure. Here the authors demonstrate ReMOT Control, delivery of RNPs to the mosquito germline by tagging with peptide derived from yolk protein 1.

The fruit fly, Drosophila melanogaster, is predominantly found in overripe, rotten, fermenting, or decaying fruits and is constantly exposed to chemical stressors such as acetic acid, ethanol, and 2-phenylethanol. D. melanogaster has been employed as a model system for studying the molecular bases of various types of chemical-induced tolerance. Expression profiling using Illumina sequencing has been performed for identifying changes in gene expression that may be associated with evolutionary adaptation to exposure of acetic acid, ethanol, and 2-phenylethanol. We identified a total of 457 differentially expressed genes that may affect sensitivity or tolerance to three chemicals in the chemical treatment group as opposed to the control group. Gene-set enrichment analysis revealed that the genes involved in metabolism, multicellular organism reproduction, olfaction, regulation of signal transduction, and stress tolerance were over-represented in response to chemical exposure. Furthermore, we also detected a coordinated upregulation of genes in the Toll- and Imd-signaling pathways after the chemical exposure. Quantitative reverse transcription PCR analysis revealed that the expression levels of nine genes within the set of genes identified by RNA sequencing were up- or downregulated owing to chemical exposure. Taken together, our data suggest that such differentially expressed genes are coordinately affected by chemical exposure. Transcriptional analyses after exposure of D. melanogaster with three chemicals provide unique insights into subsequent functional studies on the mechanisms underlying the evolutionary adaptation of insect species to environmental chemical stressors.

International audience; Ticks are important ectoparasites and vectors of numerous human and animal pathogens. Ticks secrete saliva that contains various bioactive materials to evade the host defense system, and often facilitates the pathogen transmission. In addition, the Lone star tick saliva is thought to be the sensitizer in red meat allergy that is characterized by an allergic reaction to glycan moieties carrying terminal galactose-alpha-1,3-galactose (aGal). To assess N-glycome of Amblyomma americanum, we examined the N-glycan structures in male and female salivary glands at three different feeding stages and in carcasses of partially fed lone star ticks. We also surveyed the genes involved in the N-glycosylation in the tick species. The aGal epitopes and cross-reactive carbohydrate determinants (CCD) increases over time after the onset of blood feeding in both male and female A. americanum. These CCDs include xylosylation of the core mannose, 1,3-mono and 1,3- and 1,6-difucosylations of the basal GlcNac and mono- or diantennary aGal. Combinations of both xylosylation and aGal and fucosylation and aGal were also found on the N-glycan structures. While the enzymes required for the early steps of the N-glycosylation pathway are quite conserved, the enzymes involved in the later stages of N-glycan maturation in the Golgi apparatus are highly diverged from those of insects. Most of all, we propose that the aGal serves as a molecular mimicry of bioactive proteins during tick feedings on mammalian hosts, while it contributes as a sensitizer of allergy in atypical host human.

International audience; Ticks can survive in harsh and fluctuating vegetated environments for long durations between blood feedings with highly developed osmoregulatory mechanisms. Like the unique life history of hematophagous ticks, osmoregulatory organs and their regulatory mechanisms are significantly different from those in the closely related insect taxa. Over the last ten years, research has uncovered several neuropeptidergic innervations of the primary osmoregulatory organ, the salivary glands: myoinhibitory peptide (MIP), SIFamide, and elevenin. These neuropeptides are thought to be modulators of dopamine's autocrine or paracrine actions controlling the salivary glands, including the activation of fluid transport into the lumen of salivary acini and the pumping and gating action of salivary acini for expelling fluids out into salivary ducts. These actions are through two different dopamine receptors, D1 receptor and invertebrate D1-like dopamine receptor, respectively. Interestingly, MIP and SIFamide are also involved in the control of another important excretory/osmoregulatory organ, the hindgut, where SIFamide is myostimulatory, with MIP having antagonistic effects. FGLamide related allatostatin is also found to have axonal projections located on the surface of the rectum. Investigations of the osmoregulatory mechanisms of these critical vector species will potentially lead to the development of a measure to control tick species.

The lone star tick, Amblyomma americanum, is an obligatory ectoparasite of many vertebrates and the primary vector of Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis. This study aimed to investigate the comparative transcriptomes of A. americanum underlying the processes of pathogen acquisition and of immunity towards the pathogen. Differential expression of the whole body transcripts in six different treatments were compared: females and males that were E. chaffeensis non-exposed, E. chaffeensis-exposed/uninfected, and E. chaffeensis-exposed/infected. The Trinity assembly pipeline produced 140,574 transcripts from trimmed and filtered total raw sequence reads (approximately 117M reads). The gold transcript set of the transcriptome data was established to minimize noise by retaining only transcripts homologous to official peptide sets of Ixodes scapularis and A. americanum ESTs and transcripts covered with high enough frequency from the raw data. Comparison of the gene ontology term enrichment analyses for the six groups tested here revealed an up-regulation of genes for defense responses against the pathogen and for the supply of intracellular Ca(++) for pathogen proliferation in the pathogen-exposed ticks. Analyses of differential expression, focused on functional subcategories including immune, sialome, neuropeptides, and G protein-coupled receptor, revealed that E. chaffeensis-exposed ticks exhibited an upregulation of transcripts involved in the immune deficiency (IMD) pathway, antimicrobial peptides, Kunitz, an insulin-like peptide, and bursicon receptor over unexposed ones, while transcripts for metalloprotease were down-regulated in general. This study found that ticks exhibit enhanced expression of genes responsible for defense against E. chaffeensis.

Tick salivary glands play critical roles in maintaining water balance for survival, as they eliminate excess water and ions during blood feeding on hosts. In the long duration of fasting in the off-host period, ticks secrete hygroscopic saliva into the mouth cavity to uptake atmospheric water vapor. Type I acini of tick salivary glands are speculated to be involved in secretion of hygroscopic saliva based on ultrastructure studies. However, we recently proposed that type I acini play a role in resorption of water/ions from the primary saliva produced by other salivary acini (i.e., types II and III) during the tick blood feeding phase. In this study, we tested the function of type I acini in unfed femaleIxodes scapularis. The route of ingested water was tracked after forced feeding of water with fluorescent dye rhodamine123. We found that type-I acini of the salivary glands, but not type II and III, are responsible for water uptake. In addition, the ingestion of water through the midgut was also observed. Injection or feeding of ouabain, a Na/K-ATPase inhibitor, suppressed water absorption in type I acini. WhenI. scapulariswas offered a droplet of water, ticks rarely imbibed water directly (5%), while some approached the water droplet to use the high humidity formed in the vicinity of the droplet (23%). We conclude that during both on- and off-host stages, type I acini in salivary glands of femaleIxodes scapularisabsorb water and ions.

The objective of this study was to investigate the physico-chemical and sensory properties of loin (m. longissimus dorsi) and top round (m. semimembranosus) beef from 3-, 6-, 9-, and 12 mon-old Holstein calves. For both loin and top round muscles, the moisture contents were decreased, whereas the protein and fat contents were increased, as the slaughtering age increased. In terms of meat color, for both muscle types, CIE L* values were decreased, whereas CIE a* values and myoglobin content increased as the slaughtering age increased. pH values were significantly higher in the 3 mon-old group than in the other groups. The Warner-Bratzler shear force (WBSF) values were lowest for loin muscles from the 12 mon-old group; however, there was no significant difference for top round muscle among the 4 age groups. Cooking loss for both loin and top round muscles were significantly higher for the 3 mon-old group than for the other groups. The water holding capacity (WHC) of both muscles were highest for the 12 mon-old groups (p

Control of salivary secretion in ticks involves autocrine dopamine activating two dopamine receptors: D1 and Invertebrate-specific D1-like dopamine receptors. In this study, we investigated Na/K-ATPase as an important component of the secretory process. Immunoreactivity for Na/K-ATPase revealed basal infolding of lamellate cells in type-I, abluminal interstitial (epithelial) cells in type-II and labyrinth-like infolding structures opening towards the lumen in type-III acini. Ouabain (10 μmol l−1), a specific inhibitor of Na/K-ATPase, abolished dopamine-induced salivary secretion by suppressing fluid transport in type III acini. At 1 μmol l−1, ouabain, the secreted saliva was hyperosmotic. This suggests that ouabain also inhibits an ion resorptive function of Na/K-ATPase in the type I acini. Dopamine/ouabain were not involved in activation of protein secretion, while dopamine-induced saliva contained constitutively basal level of protein. We hypothesize that the dopamine-dependent primary saliva formation, mediated by Na/K-ATPase in type III and type II acini, is followed by a dopamine-independent resorptive function of Na/K-ATPase in type I acini located in the proximal end of the salivary duct.

The varroa mite, Varroa destructor, is a devastating ectoparasite of the honey bees Apis mellifera and A. cerana. Control of these mites in beehives is a challenge in part due to the lack of toxic agents that are specific to mites and not to the host honey bee. In searching for a specific toxic target of varroa mites, we investigated two closely related neuropeptidergic systems, tachykinin-related peptide (TRP) and natalisin (NTL) and their respective receptors. Honey bees lack both NTL and the NTL receptor in their genome sequences, providing the rationale for investigating these receptors to understand their specificities to various ligands. We characterized the receptors for NTL and TRP of V. destructor (VdNTL-R and VdTRP-R, respectively) and for TRP of A. mellifera (AmTRP-R) in a heterologous reporter assay system to determine the activities of various ligands including TRP/NTL peptides and peptidomimetics. Although we found that AmTRP-R is highly promiscuous, activated by various ligands including two VdNTL peptides when a total of 36 ligands were tested, we serendipitously found that peptides carrying the C-terminal motif -FWxxRamide are highly specific to VdTRP-R. This motif can serve as a seed sequence for designing a VdTRP-R-specific agonist.

Ticks transmit more pathogens to humans and animals than any other arthropod. We describe the 2.1 Gbp nuclear genome of the tick, Ixodes scapularis (Say), which vectors pathogens that cause Lyme disease, human granulocytic anaplasmosis, babesiosis and other diseases. The large genome reflects accumulation of repetitive DNA, new lineages of retro-transposons, and gene architecture patterns resembling ancient metazoans rather than pancrustaceans. Annotation of scaffolds representing ∼57% of the genome, reveals 20,486 protein-coding genes and expansions of gene families associated with tick–host interactions. We report insights from genome analyses into parasitic processes unique to ticks, including host ‘questing’, prolonged feeding, cuticle synthesis, blood meal concentration, novel methods of haemoglobin digestion, haem detoxification, vitellogenesis and prolonged off-host survival. We identify proteins associated with the agent of human granulocytic anaplasmosis, an emerging disease, and the encephalitis-causing Langat virus, and a population structure correlated to life-history traits and transmission of the Lyme disease agent., This project has been funded in part with federal funds from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, Department of Health and Human Services (NIAID, NIH, DHHS) under contract numbers N01-AI30071, HHSN272200900007C, HHSN266200400001C and 5R01GM77117-5. Its contents are solely the responsibility of the authors and do not represent the official views of the NIH. Additional grants and contracts supporting work described in this manuscript were from the NIH-NIAID (HHSN266200400039C and HHSN272200900039C) to F.H.C., and a subcontract under HHSN272200900039C to C.A.H. and J.M.M., the Australian Research Council Discovery Project (DP120100240) to S.C.B. and R.S., the Ministerio de Ciencia e Innovación of Spain (BFU2007–6292; BFU2010–15484) to J.R., BIO2009–07990 and BIO2012–37926 to J.V. NIH-1R01AI090062 to Y.P., L.S., and J.K., NIH 1R21AI096268 and NSF IOS-0949194 to R.M.R., the Xunta de Galicia of Spain (10PXIB918057PR) to J.M.C.T. and M.T., BFU2011–23896 and EU FP7 ANTIGONE (278976) to J.F., the USDA-NRI/CREES (2008-35302-18820) and Texas AgriLife Research Vector Biology grant to P.V.P. and European Research Council Starting Independent Researcher Grant (205202) to R.B., J.M.R was supported by the intramural program of the NIAID, R.M.W. by a Marie Curie International Outgoing Fellowship PIOF-GA-2011–303312, E.M.Z. by Swiss National Science Foundation awards 31003A-125350 and 31003A-143936, J.M.G. by an NIH-NCATS award TL1 TR000162 and NSF Graduate Research Fellowship (DGE 1333468), V.C. by a Boehringer Ingelheim Ph.D. Fellowship, F.G.V. by a Fundação para a Ciência e a Tecnologia, Portugal fellowship (SFRH/BD/22360/2005), C.J.P.G. and F.H. by The Lundbeck Foundation (Denmark), and J.J.G. by NIH awards HHSN272200900040C, R01AI017828 and R01AI043006. Support from the Broad Genomics Platform is gratefully acknowledged.

The aim of this study was to screen lactic acid bacteria for the fermentation of garlic and to assess the increase in inhibitory activity of garlic fermented against antibiotic-resistant pathogens for use as an animal feed supplement. We screened 45 strains of lactobacillus for the fermentation of garlic. Of these strains, 23 showed similar growth rates with or without allicin. Cultures of the 23 strains were mixed with an equivalent amount of garlic juice and incubated overnight at 37°C. The three strains with the lowest pH values were Lactobacillus paracasei KCTC 3169, L5 strain, and L. reuteri SW. Garlic juice fermented by the L5 strain more strongly inhibited antibiotic-resistant pathogenic bacteria than L. paracasei KCTC 3169, L. reuteri SW, or garlic juice itself. By examining carbohydrate utilization, morphologic properties and 16S rRNA gene sequences, we identified the L5 strain as Pediococcus pentosaceus and deposited it in the name of P pentosaceus KACC 91419 into the Korea Agricultural Culture Collection. To identify the antimicrobial compound from the garlic filtrate fermented by P pentosaceus KACC 91419, we fractionated P. pentosaceus KACC 91419 culture on a C 18 column and checked the antimicrobial activity of fractions A6 to A10. Only fraction A9 showed inhibitory activity on Staphylococcus aureus. Comparing the mass spectra of the fractions with and without antimicrobial activity, we observed a single dominant product ion (m/z 157.99) from the fraction showing antimicrobial activity. Its molecular mass (157.99) was 2 atomic mass units less than that of allicin (162.02). This suggests that allicin might be converted to its derivative, which has antimicrobial activity, during fermentation by P pentosaceus KACC 91419.

The aim of this study was to develop a new starter for fermented milk. The approach started with 103 acid-producing isolates from Kimchi, a type of spiced, fermented cabbage and then PCR screening was used to identify 72 Lactobacillus strains. The ability to inhibit the growth of food-borne human pathogens (Escherichia coli, Salmonella enteritidis, Staphylococcus aureus) of these strains were measured, using the paper disk method. Among them, one bacterium (LHB55) that showed a strong antibacterial activity against food-borne human pathogens was identified and further characterized, using 16S rDNA sequencing and API 50CHL system. Because this isolate was identified as L. plantarum, it was named as L. plantarum LHB55. The yogurt produced using commercial LAB with L. plantarum LHB55 did not display properties that are microbially or physico-chemically different from the control group, which suggests that L. plantarum LHB55 can be used as a useful starter for yogurt containing high antibacterial activity. We think that identifying effective starter strains enabling further development of fermented milk that can deliver better health benefits such as antimicrobial properties is of high significance, and thus our effort in this type of approach will continue. (Key words : Kimchi, Lactic acid bacteria, Lactobacillus plantarum, Antibacterial activity, Yogurt)

The aim of our study was to develop a new starter culture for fermented milk. Polymerase chain reaction screening of 103 acid-producing isolates from Kimchi identified 72 Lactobacillus strains. The ability of the strains to inhibit the growth of the food-borne human pathogens (Escherichia coli, Salmonella Enteritidis, Staphylococcus aureus) was measured, using a conventional paper disk method. Among the 72 strains, strain LHC52 displayed potent antagonistic activity. Use of 16S rDNA sequencing and the API 50CHL system identified the strain as Lactobacillus plantarum and it was designated L. plantarum LHC52. Biochemical analyses revealed especially high antibacterial activity against E. coli. Yogurt produced using L. plantarum LHC52 did not show different microbiological and physicochemical properties compared to conventionally-prepared yogurt, implicating L. plantarum LHC52 as a useful, potently antibacterial starter culture for yogurt preparation.

산양유의 체세포수는 측정방법에 따라 많은 차이가 보고되고 있으나 국제적인 표준방법으로 pyronin Y-methyl green stain에 의한 직접현미경법이 사용되고 있다. 8개 목장 총 48개 시료를 pyronin Y-methyl green stain에 의한 직접검경법, 국립축산과학원에서 보유중인 ADAM-SCC, 충청북도 축산위생연구소에서 보유중인 Somacount 500으로 측정하여 결과를 비교하였다. Pyronin Y-methyl green stain 측정시 전체 평균은 $7.3{\times}10^5$ cells/mL인 반면 ADAMSCC와 Somacaount 500은 각각 $4.9{\times}10^5$ 과 $11.6{\times}10^5$ cells/mL로 나타나 과소 또는 과대평가되는 결과를 보였다. 직접현미경법과 ADAM-SCC또는 Somacaount 500과의 상관계수는 각각 0.0332 또는 0.2285로 매우 낮으며 장비간의 상관계수도 0.1552로 매우 낮게 나타났다. 산양유의 체세 포수 저감을 위해서는 측정장비의 개발이 필요하며 장비를 표준화하기 위한 표준측정법으로 pyronin Y-methyl green stain의 채택이 필요하다. 【The standard method for somatic cell counts in goat milk is the direct microscopic method after a pyronin Y-methyl stain. It has been reported, however, that are found to differ by measuring methods, but. A total of forty eight goat milk samples from eight farms were compared by pyronin Y-methyl stain, ADAM-SCC in National Institute of Animal Science, and Somacount 500 in Chungbuk Veterinary Service. The average SCC of the samples was $7.3{\times}10^5$ cells/mL by pyronin Y-methyl stain, $4.9{\times}10^5$ cells/mL by ADAM-SCC, and $11.6{\times}10^5$ cells/mL by Somacount 500. The correlations between the methods were not significant. SCC measuring equipment should be developed for reducing the SCC in goat milk, and pyronin Y-methyl green stain for estimating SCC in goat milk should be included in NVRQS Notice for livestock products processing and composition standards.】

In this study, the quality of chicken breasts from organically reared chickens was compared with that of chicken breastsfrom conventionally reared chickens. Broilers were raised in an indoor pen with conventional and organic production sys-tem, respectively. The diet formulation for the organically reared chickens and the production density were in accordancewith the guidelines for organic chicken products. Twenty birds from each group were slaughtered and their breasts wereobtained for analysis. The organic chicken breasts had a higher cooking loss, and waterholding capacity, and a lower shearforce ( p

The characteristics of Holstein colostrum according to the methods that were employed in processing it were analyzed in this study to improve its industrial utilization. Colostrum samples were collected from the dairy farm of the National Institute of Animal Science (NIAS). The milk fat, protein, lactose, and SNF contents of colostrum were 4.34, 6.99, 3.37, and 11.10%, respectively. The effects of spray drying, freeze drying, freezing, acidification, and inoculation of lactic-acid bacteria on the characteristics of colostrum were then compared. The freezing of colostrum was found to be proper for long-term storage in a farm. Freeze-dried colostrum powder could not meet the processing requirements and the component standards for animal products in terms of the total bacterial and coliform bacteria counts, but spray-dried colostrum powder could meet the microbiological requirements because of its bactericidal effect during the spray-dry treatment. The inoculation of lactic-acid bacteria showed a better inhibitory effect on coliform than the acidification treatment, but protein precipitation appeared because of the low pH and the high acidity. To estimate the effects of the processing methods employed on the IgG of colostrum, the IgG contents of the milk treated by long temperature long time (LTLT) (65 o C, 30 min), by inoculating the lactic acid bacteria starter, by spray drying, and by freeze drying were measured. The IgG contents of the colostrum were changed significantly by the processing treatment employed, from 53.98 mg/mLto 33.28, 34.82, 21.98, and 36.89 mg/mL, respectively.

The objective of this research was to evaluate the chemico-physical and sensory traits of Hanwoo beef quality grade (), grade (), grade 1 (HW1), and Australian Wagyu (AUW) beef. The Longissimus Lumborum (LL) of beef had the lowest (p (25.58%), (16.39%), HW1 (11.29%), and AUW (11.87%) beef. Warner-Bratzler shear force (WBSF) values were the lowest in the beef from AUW (2.81 kg) beef. Cooking loss of AUW beef had the highest value (23.77%) among the beef groups. Quality grade affected sensory traits, with receiving highest (p, there were significant increases in fat content (from 11.29% to 25.58%), CIE L value (37.56 to 43.15), WHC (55.97% to 60.05%), tenderness (4.63 to 5.28), and decreases in moisture contents (66.84% to 54.07%), protein contents (20.35 to 19.76%), and WBSF value (5.43 kg to 2.93 kg) value. In sensory evaluation, overall acceptability score for Hanwoo grade beef was significantly higher than for Australian Wagyu beef. However, there were no significant differences in sensory properties between Hanwoo 1, grade and Australian Wagyu beef.

Three heat shock protein (HSP) genes (hsp70, hsc70, hsp90) were partially cloned from the brown planthopper Nilaparvata lugens and the small brown planthopper Laodelphax striatellus (Homoptera: Delphacidae), which are serious pests of the rice plant. Sequence comparisons at the deduced amino acid level showed that the three HSPs of planthoppers were most homologous to corresponding HSPs of dipteran and lepi- dopteran species. Identities of both heat shock cognate 70 and HSP90 were higher than HSP70 in both species. Identity of the HSP70 between the two planthopper species was only 81%, a value much lower than seen among fly and moth groups. Effects of heat and cold shocks were demonstrated on expression of the three hsp genes in the two planthopper species. Heat shock (40 o C) upregulated the hsp90 level but did not change the hsc70 level in either the nymph and adult stages of either species. On the other hand, the hsp70 level was only upregulated in L. striatellus. This heat shock response was prompt and lasted only for 1 h after treatment. In contrast, cold shock at 4 o C did not change the expression levels of any hsp in either species.

The objective of this study was to evaluate the effect of dietary lycopene supplementation on meat quality in Longissimus Muscle of Korean native pigs. Meat samples were obtained from pigs which had been fed with finishing pig diets containing basal diets (C), 200 ppm lycopene (T1), 400 ppm lycopene (T2), and 800 ppm lycopene (T3). Longissimus muslce pH was not influenced by feeding lycopene. Total microbial counts of treatments were significantly lower than those of control at 0 day of storage (p

Effects of wood vinegar on the activity of various insecticides were determined by measuring the mortality of two species of rice planthoppers, Nilaparvata lugens and Laodelphax striatellus. Wood vinegar itself did not show insecticidal activity on planthoppers. When the planthoppers were treated with wood vinegar mixed with one of insecticides such as BPMC, dinotefuran, imidacloprid, carbosulfan or insect growth regulators, the planthopper mortality induced by carbosulfan was greatly increased by the wood vinegar in comparison with a single carbosulfan treatment. Wood vinegar showed no effect on other insecticides. In addition, the wood vinegar‐carbosulfan mixture significantly reduced AChE activity of planthoppers, which is a target molecule of carbosulfan. This result suggests that wood vinegar has a synergistic effect on the insecticidal activity of carbosulfan. Our study provides information on a potential role of wood vinegar in facilitation of activity of specific insecticides.

Salivary secretion is crucial for successful tick feeding, and it is the mediator of pathogen transmission. Salivation functions to inhibit various components of the host immune system and remove excess water and ions during the ingestion of large blood meals. Control of salivary glands involves autocrine/paracrine dopamine, which is the most potent inducer of tick salivation. Previously, we reported the presence of two dopamine receptors in the salivary glands of the blacklegged tick (Ixodes scapularis): dopamine receptor (D1) and invertebrate specific D1-like dopamine receptor (InvD1L). Here, we investigated the different physiological roles of the dopamine receptors in tick salivary glands by using pharmacological tools that discriminate between the two distinct receptors. Heterologous expressions followed by reporter assays of the dopamine receptors identified receptor-specific antagonists and agonists. These pharmacological tools were further used to discriminate the physiological role of each receptor by using in vitro assays: measuring salivary secretions of isolated salivary glands and monitoring dynamic changes in the size of individual salivary gland acini. We propose that the D1 receptor acts on salivary gland acini epithelial cells for inward fluid transport. InvD1L controls (or modulates) each acinus for expelling saliva from the acini to the salivary ducts, presumably through the actions of myoepithelial cells and valves for pumping/gating. We conclude that dopamine acts on the D1 and the InvD1L receptors and leads different physiological actions to orchestrate tick salivary secretion.