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Manduca sexta, known as the tobacco hornworm or Carolina sphinx moth, is a lepidopteran insect that is used extensively as a model system for research in insect biochemistry, physiology, neurobiology, development, and immunity. One important benefit of this species as an experimental model is its extremely large size, reaching more than 10 g in the larval stage. M. sexta larvae feed on solanaceous plants and thus must tolerate a substantial challenge from plant allelochemicals, including nicotine. We report the sequence and annotation of the M. sexta genome, and a survey of gene expression in various tissues and developmental stages. The Msex_1.0 genome assembly resulted in a total genome size of 419.4 Mbp. Repetitive sequences accounted for 25.8% of the assembled genome. The official gene set is comprised of 15,451 protein-coding genes, of which 2498 were manually curated. Extensive RNA-seq data from many tissues and developmental stages were used to improve gene models and for insights into gene expression patterns. Genome wide synteny analysis indicated a high level of macrosynteny in the Lepidoptera. Annotation and analyses were carried out for gene families involved in a wide spectrum of biological processes, including apoptosis, vacuole sorting, growth and development, structures of exoskeleton, egg shells, and muscle, vision, chemosensation, ion channels, signal transduction, neuropeptide signaling, neurotransmitter synthesis and transport, nicotine tolerance, lipid metabolism, and immunity. This genome sequence, annotation, and analysis provide an important new resource from a well-studied model insect species and will facilitate further biochemical and mechanistic experimental studies of many biological systems in insects.

A gene that is negatively controlled by ecdysteroids was isolated and partially characterized from the trachea of Manduca sexta. A 20-kda protein is encoded by the Ecdysteroid Regulated 20 gene. Sites implicated in the four proteins examined exhibit protein-protein interactions.

Judgments about animal suffering are of central importance in evaluating scientific protocols. To make such judgments we must confront a set of problematic practical questions: How are we to predict [...]

Background: Veterinarians are faced with significant conflicts of interest when issuing certificates for the transport and slaughter of acutely injured and casualty livestock. In a recent Policy Delphi study, emergency and casualty slaughter certification was a key concern identified by veterinary professionals in Ireland. In this case study (the third in a series of three resulting from a research workshop exploring challenges facing the veterinary profession in Ireland; the other two case studies investigate clinical veterinary services and the on-farm use of veterinary antimicrobials), we aim to provide a value-based reflection on the constraints and opportunities for best practice in emergency and casualty slaughter certification in Ireland. Results: Using a qualitative focus group approach, this study gathered evidence from relevant stakeholders, namely a representative from the regulatory body, local authority veterinarians with research experience in emergency slaughter, an animal welfare research scientist, official veterinarians from the competent authority, a private veterinary practitioner, and a member of a farming organisation. Results revealed a conflict between the responsibility of private veterinary practitioners (PVPs) to safeguard the welfare of acutely injured bovines on-farm and the client’s commercial concerns. As a consequence, some PVPs may feel under pressure to certify, for example, an acutely injured animal for casualty slaughter instead of recommending either on-farm emergency slaughter or disposal by the knackery service. Among Official Veterinarians, there are concerns about the pressure within processing plants to accept acutely injured livestock as casualty animals. Confusion pertaining to legislation and definition of fitness to travel also contribute to these dilemmas. Conclusions: Conflicts of interest arise due to the gap between governance and provision to facilitate on-farm emergency slaughter of livestock. Increased availability and acceptance of on-farm emergency slaughter by Food Business Operators (FBOs) would mitigate the need to certify acutely injured animals fit for transport and slaughter and thereby safeguard animal welfare. In the absence of nationwide availability and acceptance of on-farm emergency slaughter by FBOs, consideration should be given to methods to encourage all those involved in the food chain to prioritise animal welfare when in conflict with the commercial value of the animal. Training and guidelines for PVPs on the regulatory landscape and ethical decision-making should become available. The reintroduction of the fallen animal scheme should be considered to support farm animal welfare. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance has emerged in recent years as a significant public health threat, which requires both an ethical and a scientific approach. In a recent Policy Delphi study, on-farm use of antimicrobials was a key concern identified by veterinary professionals in Ireland. In this case study (the second in a series of three resulting from a research workshop exploring the challenges facing the veterinary profession in Ireland; the other two case studies investigate clinical veterinary services and emergency/casualty slaughter certification) we aim to provide a value-based reflection on the constraints and possible opportunities for responsible use of veterinary antimicrobials in Ireland. Results: Using a qualitative focus group approach, this study gathered evidence from relevant stakeholders, namely veterinarians working in public and private organisations, a representative from the veterinary regulatory body, a dairy farmer and a general medical practitioner. Three overarching constraints to prudent on-farm use of veterinary antimicrobials emerged from the thematic analysis: ‘Defective regulations’, ‘Lack of knowledge and values’ regarding farmers and vets and ‘Farm-centred concerns’, including economic and husbandry concerns. Conversely, three main themes which reflect possible opportunities to the barriers were identified: ‘Improved regulations’, ‘Education’ and ‘Herd health management’. Conclusions: Five main recommendations arose from this study based on the perspectives of the study participants including: a) the potential for regulatory change to facilitate an increase in the number of yearly visits of veterinarians to farms and to implement electronic prescribing and shorter validity of prescriptions; b) a ‘One Health’ education plan; c) improved professional guidance on responsible use of veterinary antimicrobials; d) improved on-farm herd health management practices; and e) the promotion of a ‘One Farm-One Vet’ policy. These findings may assist Veterinary Council of Ireland and other competent authorities when revising recommendations concerning the prudent use of veterinary antimicrobials in farmed animals. [ABSTRACT FROM AUTHOR]

TAR DNA-binding protein 43 (TDP-43) is an RNA-binding protein that regulates transcription, translation and alternative splicing of mRNA. We have shown previously that null mutations of the Drosophila ortholog, Tar DNA-binding homolog (tbph), causes severe locomotion defects in larvae that are mediated by a reduction in the expression of a type II voltage-gated calcium channel, cacophony (cac). We also showed that TDP-43 regulates the inclusion of alternatively spliced exons of cacophony; tbph mutants showed significantly increased expression of cacophony isoforms lacking exon 7, a particularly notable finding as only one out of the 15 predicted isoforms lacks exon 7. To investigate the function of exon 7, we generated Drosophila mutant lines with a deletion that eliminates exon 7. This deletion phenocopies many defects in tbph mutants: a reduction in cacophony protein (Dmca1A) expression, locomotion defects in male and female third instar larvae, disrupted larval motor output, and also reduced activity levels in adult male flies. All these defects were rescued by expression of cacophony transcripts containing exon 7. By contrast, expression of a cacophony cDNA lacking exon 7 resulted in reduced cacophony protein levels and failed to rescue larval locomotion. [ABSTRACT FROM AUTHOR]

That Science should have chosen Adrian R. Morrison to review the book The Human Use of Animals: Case Studies in Ethical Choice (1) (Science's Compass, 8 Jan., p. 181), of [...]

Background: The provision of veterinary clinical services is known to elicit a range of challenges which require an ethical appraisal. In a recent Policy Delphi study, referrals/second opinions and 24 h emergency care were identified as matters of key concern by veterinary professionals in Ireland. In this case study (the first in a series of three resulting from a research workshop exploring challenges facing the veterinary profession in Ireland; the other two case studies investigate the on-farm use of veterinary antimicrobials and emergency/casualty slaughter certification) we aim to provide a value-based reflection on the constraints and possible opportunities for two prominent veterinary clinical services in Ireland: referrals/second opinions and 24 h emergency care. Results: Using a qualitative focus group approach, this study gathered evidence from relevant stakeholders, namely referral and referring veterinarians, clients, animal charities, and the regulatory body. Six overarching, interrelated constraints emerged from the thematic analysis: the need to improve current guidance, managing clients’ expectations, concerns with veterinarian well-being, financial issues, timeliness of referral, and conflicts between veterinary practices. Conclusions: Possible solutions to improve veterinary referral and out-of-hours clinical services included clarifying the terms used in current norms and regulations (namely ‘referral’, ‘second opinion’, ‘24 h emergency care’ and ‘24 h cover’), improved communication (making the client aware of the different levels of veterinary care that are being offered, and transparent and full disclosure of clinical records), and the promotion of Continuing Veterinary Education in communication, business management and ethical decision-making. These findings may help inform the Veterinary Council of Ireland about future recommendations and regulatory measures. [ABSTRACT FROM AUTHOR]

Defects in the RNA-binding protein, TDP-43, are known to cause a variety of neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal lobar dementia. A variety of experimental systems have shown that neurons are sensitive to TDP-43 expression levels, yet the specific functional defects resulting from TDP-43 dysregulation have not been well described. Using the Drosophila TDP-43 ortholog TBPH, we previously showed that TBPH-null animals display locomotion defects as third instar larvae. Furthermore, loss of TBPH caused a reduction in cacophony, a Type II voltage-gated calcium channel, expression and that genetically restoring cacophony in motor neurons in TBPH mutant animals was sufficient to rescue the locomotion defects. In the present study, we examined the relative contributions of neuromuscular junction physiology and the motor program to the locomotion defects and identified subsets of neurons that require cacophony expression to rescue the defects. At the neuromuscular junction, we showed mEPP amplitudes and frequency require TBPH. Cacophony expression in motor neurons rescued mEPP frequency but not mEPP amplitude. We also showed that TBPH mutants displayed reduced motor neuron bursting and coordination during crawling and restoring cacophony selectively in two pairs of cells located in the brain, the AVM001b2b neurons, also rescued the locomotion and motor defects, but not the defects in neuromuscular junction physiology. These results suggest that the behavioral defects associated with loss of TBPH throughout the nervous system can be associated with defects in a small number of genes in a limited number of central neurons, rather than peripheral defects. [ABSTRACT FROM AUTHOR]