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Kavitha Kongara, John Paul Chambers Animal Welfare Science and Bioethics Centre, School of Veterinary Science, Massey University, Palmerston North, New Zealand Abstract: Robenacoxib is a novel nonsteroidal anti-inflammatory drug (NSAID) of coxib class developed for the control of inflammation and pain in dogs and cats. It shows high selectivity for the cyclooxygenase-2 (COX-2) enzyme in rats, cats, and dogs. Robenacoxib is available in both injectable and tablet formulations. This review initially focuses on the preclinical pharmacology of robenacoxib in rats that includes its high affinity for COX-2 enzyme and weaker and rapidly reversible binding for COX-1 enzyme in in vitro and ex vivo models of inflammation and its pharmacokinetics in the blood and inflammatory exudate, selective tissue distribution, and safety. These basic pharmacological profiles highlight the suitability of robenacoxib for use in target species, such as cats and dogs. Since the level of expression and activity of COX enzymes is species specific, COX-2-selective inhibition and the resultant effects of coxibs must be studied in target species. The pharmacological and toxicological profiles of robenacoxib in cats and dogs have been discussed prior to reviewing its clinical efficacy and safety. Large, multicenter field trials conducted in cats and dogs demonstrated the noninferior efficacy and safety of robenacoxib compared with noncoxib NSAIDs used in dogs and cats. These trials investigated the efficacy of robenacoxib against various acute and chronic painful conditions. Robenacoxib produced superior efficacy to placebo and COX-2 preferential inhibitors in postsurgical cats. The tissue-selective anti-inflammatory activity of robenacoxib has been demonstrated in dogs with osteoarthritis. Robenacoxib has also been shown to be safe in healthy dogs and cats receiving antihypertensive drugs and loop diuretics that could cause renal injury. The developmental objective of coxibs, comparable efficacy but superior safety to less selective/nonselective NSAIDs, is well established with robenacoxib in preclinical studies. More studies need to be conducted to fully explore the benefits of robenacoxib in clinical subjects. Keywords: robenacoxib, preclinical pharmacology, clinical studies, analgesia, tolerability

AIMS: To survey current anaesthesia practices for dogs and cats in small and mixed animal practices in New Zealand in order to improve anaesthesia education. METHODS: A questionnaire was sent to 440 small and mixed animal practices, including questions regarding the type of practice, preanaesthetic examination, anaesthetic drugs and management, anaesthetic machines, monitoring and topics of interest for continuing professional development. RESULTS: Responses were obtained from 113/440 (26%) practices, with 78 (69%) respondents from small and 35 (31%) from mixed animal practices. A preanaesthetic physical examination was carried out by >95% of respondents and premedication was usually given to dogs (112/113; 99%) and cats (95/113; 85%). Acepromazine was the preferred sedative for dogs and cats, with morphine or buprenorphine. Propofol and alfaxalone were the preferred induction agents, and isoflurane was preferred for maintenance in both dogs and cats. A venous catheter was usually placed for anaesthesia in dogs (59/113; 52%), but less so in cats (39/113; 35%). Perioperative fluid was administered at 10 mL/kg/hour by 62/110 (56%) respondents. Intubation was usually used for anaesthesia in dogs (111/112; 99%), and cats (87/112; 78%). Almost 40% of respondents usually administered supplementary oxygen if patients were not intubated. Local analgesia was used by 69/111 (88%) respondents sometimes or always if applicable. Morphine or buprenorphine, and meloxicam were common choices for post-operative analgesia after neuter surgery in dogs and cats. A semiclosed (non-rebreathing) system was used in animals weighing <10 kg, and a Mapleson E or F non-rebreathing circuit was used by 66/109 (61%) practices. Only 15/111 (14%) practices had a ventilator in their practice. A dedicated anaesthetist was usually used by 104/113 (92%) practices, and apnoea alarms, pulse oximeters, thermometers and oesophageal stethoscopes were the main monitoring devices available in practices. Loco-regional block, pain management, and anaesthetic drugs were the main topics of interest for continuing education. CONCLUSIONS AND CLINICAL RELEVANCE: Responses by the veterinarians taking part in this survey indicated that they had a reasonably good standard of anaesthetic practice. A physical examination was carried out preanaesthesia, and premedication including analgesia was routinely administered to most patients. A dedicated anaesthetist usually monitored patients and most respondents reported they had access to basic anaesthetic monitoring equipment. Areas where changes could lead to improved anaesthetic practice were increased use of I/V catheterisation, endotracheal intubation, and supplementary oxygen, and reduced I/V fluid rates. [ABSTRACT FROM PUBLISHER]

AIM: To develop and validate a simple and sensitive method using liquid chromatography-mass spectrometry (LC-MS) for quantification of articaine, and its major metabolite articainic acid, in plasma of red deer (Cervus elaphus), and to investigate the pharmacokinetics of articaine hydrochloride and articainic acid in red deer following S/C administration of articaine hydrochloride as a complete ring block around the antler pedicle. METHODS: The LC-MS method was validated by determining linearity, sensitivity, recovery, carry-over and repeatability. Articaine hydrochloride (40 mg/mL) was administered S/C to six healthy male red deer, at a dose of 1 mL/cm of pedicle circumference, as a complete ring block around the base of each antler. Blood samples were collected at various times over the following 12 hours. Concentrations in plasma of articaine and articainic acid were quantified using the validated LC-MS method. Pharmacokinetic parameters of articaine and articainic acid were estimated using non-compartmental analysis. RESULTS: Calibration curves were linear for both articaine and articainic acid. The limits of quantifications for articaine and articainic acid were 5 and 10 ng/mL, respectively. Extraction recoveries were >72% for articaine and >68% for articainic acid. After S/C administration as a ring block around the base of each antler, mean maximum concentrations in plasma (Cmax) of articaine were 1,013.9 (SD 510.1) ng/mL, detected at 0.17 (SD 0.00) hours, and theCmaxfor articainic acid was 762.6 (SD 95.4) ng/mL at 0.50 (SD 0.00) hours. The elimination half-lives of articaine hydrochloride and articainic acid were 1.12 (SD 0.17) and 0.90 (SD 0.07) hours, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The LC-MS method used for the quantification of articaine and its metabolite articainic acid in the plasma of red deer was simple, accurate and sensitive. Articaine hydrochloride was rapidly absorbed, hydrolysed to its inactive metabolite articainic acid, and eliminated following S/C administration as a ring block in red deer. These favourable pharmacokinetic properties suggest that articaine hydrochloride should be tested for efficacy as a local anaesthetic in red deer for removal of velvet antlers. Further studies to evaluate the safety and residues of articaine hydrochloride and articainic acid are required before articaine can be recommended for use as a local anaesthetic for this purpose. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the prevalence of disseminated Mycobacterium avium subspecies paratuberculosis (Map) infection in healthy ewes in a flock with a history of clinical Johne's disease in New Zealand. Histological tests were performed to determine the pathological lesions characteristic of Johne's disease. The detection of Map infection in ewes by enzyme-linked immunosorbent assay (ELISA) serology is highlighted.

There is a significant need to develop new environmentally friendly, extraction-free sample collection mediums that can effectively preserve and protect genetic material for point-of-care and/or self-collection, home-collection, and mail-back testing. Systematic evolution of ligands by exponential enrichment (SELEX) was used to create anti-ribonuclease (RNase) deoxyribonucleic acid (DNA) aptamers against purified RNase A conjugated to paramagnetic carboxylated beads. Following eight rounds of SELEX carried out under various stringency conditions, e.g., selection using Xtract-Free™ (XF) specimen collection medium and elevated ambient temperature of 28 °C, a panel of five aptamers was chosen following bioinformatic analysis using next-generation sequencing. The efficacy of aptamer inactivation of RNase was assessed by monitoring ribonucleic acid (RNA) integrity via fluorometric and real-time RT-PCR analysis. Inclusion of aptamers in reaction incubations resulted in an 8800- to 11,200-fold reduction in RNase activity, i.e., digestion of viral RNA compared to control. Thus, anti-RNase aptamers integrated into XF collection medium as well as other commercial reagents and kits have great potential for ensuring quality intact RNA for subsequent genomic analyses.

Multi-drug-resistant (MDR) Acinetobacter baumannii is an opportunistic pathogen associated with hospital-acquired infections. Due to its environmental persistence, virulence, and limited treatment options, this organism causes both increased patient mortality and incurred healthcare costs. Thus, prophylactic vaccination could be ideal for intervention against MDR Acinetobacter infection in susceptible populations. In this study, we employed immunoinformatics to identify peptides containing both putative B- and T-cell epitopes from proteins associated with A. baumannii pathogenesis. A novel Acinetobacter Multi-Epitope Vaccine (AMEV2) was constructed using an A. baumannii thioredoxin A (TrxA) leading protein sequence followed by five identified peptide antigens. Antisera from A. baumannii infected mice demonstrated reactivity to rAMEV2, and subcutaneous immunization of mice with rAMEV2 produced high antibody titer against the construct as well as peptide components. Immunization results in increased frequency of IL-4-secreting splenocytes indicative of a Th2 response. AMEV2-immunized mice were protected against intranasal challenge with a hypervirulent strain of A. baumannii and demonstrated reduced bacterial burden at 48 h. In contrast, all mock vaccinated mice succumbed to infection within 3 days. Results presented here provide insight into the effectiveness of immunoinformatic-based vaccine design and its potential as an effective strategy to combat the rise of MDR pathogens.

Farm animals are routinely subjected to painful husbandry procedures for various purposes. Goat kids are disbudded to improve goat welfare and to ensure safety of other livestock, farm personnel, attending veterinarians and for various other production and managemental procedures. Disbudding is commonly performed on dairy goat farms, in kids under 3 weeks of age. Many scientific studies reported physiological and behavioural changes indicating pain and distress following disbudding, and this can be a significant cause of welfare compromise in goat kids. Recognition and measurement of pain is important to treat and/or manage pain and distress following painful procedures. This review focuses on pain assessment in goat kids following disbudding, using both physiological and behavioural measures. As only a limited information is available on the topic of interest, relevant studies in other young farm animals have also been discussed to compare the status quo in goat kids.

Background: The rapid detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is vital for patient care. The LumiraDx™ SARS-CoV-2 RNA Star Complete (RSC) is an Emergency Use Authorization -recognized molecular test using nasal/nasopharyngeal swabs immersed in a viral/universal transport medium (VTM/UTM). However, there is a critical need for an alternative medium for point-of-care testing (POCT). This study aimed to investigate Xtract-Free (XF), a novel collection medium for transport and direct (extraction-free) use with nucleic acid tests. Methods: Using serially diluted SARS-CoV-2 viral RNA (vRNA) in a routine UTM and XF, a limit of detection (LOD) was established via an RSC test and a quantitative reverse transcription PCR (RT-qPCR). Additionally, the results obtained from a panel of 108 clinical "car-side" nasal swabs collected in XF during the coronavirus pandemic and assessed using the "gold-standard" RT-qPCR assay were compared to Lumira's RSC assay. Results: The average replicate RT-qPCR cycle threshold (C T ) values for vRNA in XF and UTM were observed to be equivalent. An LOD for which five out of five replicates were detected using XF or VTM was approximately 2000 copies/mL. The nasal swabs collected in XF exhibited 93.9% positive percent agreement (sensitivity) and 100% negative percent agreement (specificity) compared to the RT-qPCR. Three specimens tested positive via an RT-qPCR were negative when tested via RSC; however, all three samples had C T values ≥ 36.4. Conclusions: XF is equivalent to VTM/UTM and is compatible for use with the RSC test. Furthermore, XF can be used directly with RT-qPCRs and rapid antigen testing without the requirement for separate nucleic acid extraction (an extraction-free process), making it ideal for cost-effective high-throughput and decentralized respiratory testing. Impact Statement: This study is the first to evaluate LumiraDx's SARS-CoV-2 RNA Star Complete assay in concert with Xtract-Free (XF), a novel collection medium containing a proprietary RNase-inactivating technology for the rapid, "extraction-free" detection of SARS-CoV-2 RNA from clinical nasal swabs. Specimens collected in XF combined with rapid LumiraDx detection provide a safe and sensitive alternative to VTM/UTM, and Molecular Transport medium (MTM) for high throughput, "extraction-free" molecular detection.

Acinetobacter baumannii is a nosocomic opportunistic Gram-negative bacteria known for its extensive drug-resistant phenotype. A. baumannii hospital-acquired infections are major contributors to increased costs and mortality observed during the COVID-19 pandemic. With few effective antimicrobials available for treatment of this pathogen, immune-based therapy becomes an attractive strategy to combat multi-drug resistant Acinetobacter infection. Immunotherapeutics is a field of growing interest with advances in vaccines and monoclonal antibodies providing insight into the protective immune response required to successfully combat this pathogen. This review focuses on current knowledge describing the adaptive immune response to A. baumannii , the importance of antibody-mediated protection, developments in cell-mediated protection, and their respective therapeutic application going forward. With A. baumannii 's increasing resistance to most current antimicrobials, elucidating an effective host adaptive immune response is paramount in the guidance of future immunotherapeutic development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jeffreys, Chambers, Yu, Hung, Forsthuber and Arulanandam.)

Understanding the immune response to SARS-CoV-2 is important for development of effective diagnostics and vaccines. We report here a broad antibody response to SARS-CoV-2 spike protein receptor binding domain (RBD) in 100 convalescent patient plasma samples. Antibody isotypes IgA, IgM, and IgG exhibited significantly higher anti-RBD titers when compared to SARS-CoV-2 negative controls. IgG subtyping indicated IgG1 and IgG3 to be most abundant. Greater than 90 % of SARS-CoV-2 positive plasma samples tested exhibited significant neutralization capacity using a surrogate virus neutralization assay. Of the IgG subclasses, IgG1 and IgG3 exhibited the highest viral neutralization capacity; whereas, IgG2 and IgG4 viral neutralization was not observed. Comparison of SARS-CoV-2 elicited total IgG binding to emerging variant (alpha, beta, and delta) RBDs indicated decreased binding. Furthermore, neutralization by SARS-CoV-2 convalescent plasma of delta and omicron variant RBDs was significantly decreased suggesting that neutralizing antibodies in convalescent plasma are less effective in inhibiting variants currently in circulation.

Fetuin-A is an acute phase glycoprotein shown to counter in a regulatory manner proinflammatory cytokine production to maintain homeostasis during inflammation. We report here that in wild-type mice 12 days after Chlamydia muridarum (Cm) intranasal challenge, fetuin-A content in the lungs decreased 46%, while INF- γ increased 44%, consistent with a negative regulatory role of fetuin-A in inflammation. Importantly, the observed increased IFN- γ production was abrogated in fetuin-A-deficient AHSG mice suggesting that IFN- γ induction following Cm infection is fetuin-A dependent. Assessment of expression of genes associated with inflammation revealed fetuin-A-dependent upregulation of TBX21 (a Th1 cell-specific transcription factor) in the lungs of Cm-infected WT mice that correlated with IFN- γ induction. Additionally, the effect of fetuin-A deficiency in mounting an adaptive immune response to Cm infection was demonstrated using a splenocyte recall assay. Although preliminary in nature, these findings are suggestive of fetuin-A involvement following Cm pulmonary infection and underscores the need to investigate further the role of fetuin-A in the immune response and the consequences of its gene deletion., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2022 Faria Mahjabeen et al.)

Acinetobacter baumannii is a Gram-negative bacterium responsible for many hospital-acquired infections including ventilator-associated pneumonia and sepsis. We have previously identified A. baumannii thioredoxin A protein (TrxA) as a virulence factor with a multitude of functions including reduction of protein disulfides. TrxA plays an important role in resistance to oxidative stress facilitating host immune evasion in part by alteration of type IV pili and cell surface hydrophobicity. Other virulence factors such as outer membrane vesicles (OMV) shed by bacteria have been shown to mediate bacterial intercellular communication and modulate host immune response. To investigate whether OMVs can be modulated by TrxA, we isolated OMVs from wild type (WT) and TrxA-deficient (ΔtrxA) A. baumannii clinical isolate Ci79 and carried out a functional and proteomic comparison. Despite attenuation of ΔtrxA in a mouse challenge model, pulmonary inoculation of ΔtrxA OMVs resulted in increased lung permeability compared to WT OMVs. Furthermore, ΔtrxA OMVs induced more J774 macrophage-like cell death than WT OMVs. This ΔtrxA OMV-mediated cell death was abrogated when cells were incubated with protease-K-treated OMVs suggesting OMV proteins were responsible for cytotoxicity. We therefore compared WT and mutant OMV proteins using proteomic analysis. We observed that up-regulated and unique ΔtrxA OMV proteins consisted of many membrane bound proteins involved in small molecule transport as well as proteolytic activity. Bacterial OmpA, metalloprotease, and fimbrial protein have been shown to enhance mammalian cell apoptosis through various mechanisms. Differential packaging of these proteins in ΔtrxA OMVs may contribute to the increased cytotoxicity observed in this study.

Prenatal alcohol exposure (PAE) can result in neurobehavioral anomalies, that may be exacerbated by co-occurring metabolic and immune system deficits. To test the hypothesis that the peripheral inflammation in adult PAE offspring is linked to poor glucose metabolism and neurocognitive deficits, pregnant Sprague-Dawley rats were exposed to ethanol vapor or ambient air during the latter half of gestation. We assessed, in adult offspring of both sexes, performance on a battery of neurocognitive behaviors, glucose tolerance, circulating and splenic immune cells by flow-cytometry, and circulating and tissue (liver, mesenteric adipose, and spleen) cytokines by multiplexed assays. PAE reduced both the ratio of spleen to body weight and splenic regulatory T-cell (Treg) numbers. PAE males, but not females exhibited an increase in circulating monocytes. Overall, PAE males exhibited a suppression of cytokine levels, while PAE females exhibited elevated cytokines in mesenteric adipose tissue (IL-6 and IL1α) and liver (IFN-γ, IL-1β, IL-13, IL-18, IL-12p70, and MCP-1), along with increased glucose intolerance. Behavioral analysis also showed sex-dependent PAE effects. PAE-males exhibited increased anxiety-like behavior while PAE-females showed decreased social interaction. PAE offspring of both sexes exhibited impaired recognition of novel objects. Multilinear regression modeling to predict the association between peripheral immune status, glucose intolerance and behavioral outcomes, showed that in PAE offspring, higher levels of adipose leptin and liver TNF- α predicted higher circulating glucose levels. Lower liver IL-1 α and higher plasma fractalkine predicted more time spent in the center of an open-field with sex being an additional predictor. Higher circulating and splenic Tregs predicted better social interaction in the PAE-offspring. Collectively, our data show that peripheral immune status is a persistent, sex-dependent predictor of glucose intolerance and neurobehavioral function in adult PAE offspring., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Genomic sequence analysis of Acinetobacter baumannii revealed the presence of a putative Acid Phosphatase (AcpA; EC 3.1.3.2). A plasmid construct was made, and recombinant protein (rAcpA) was expressed in E. coli. PAGE analysis (carried out under denaturing/reducing conditions) of nickel-affinity purified protein revealed the presence of a near-homogeneous band of approximately 37 kDa. The identity of the 37 kDa species was verified as rAcpA by proteomic analysis with a molecular mass of 34.6 kDa from the deduced sequence. The dependence of substrate hydrolysis on pH was broad with an optimum observed at 6.0. Kinetic analysis revealed relatively high affinity for PNPP (Km = 90 μM) with Vmax, kcat, and Kcat/Km values of 19.2 pmoles s-1, 4.80 s-1(calculated on the basis of 37 kDa), and 5.30 x 104 M-1s-1, respectively. Sensitivity to a variety of reagents, i.e., detergents, reducing, and chelating agents as well as classic acid phosphatase inhibitors was examined in addition to assessment of hydrolysis of a number of phosphorylated compounds. Removal of phosphate from different phosphorylated compounds is supportive of broad, i.e., 'nonspecific' substrate specificity; although, the enzyme appears to prefer phosphotyrosine and/or peptides containing phosphotyrosine in comparison to serine and threonine. Examination of the primary sequence indicated the absence of signature sequences characteristic of Type A, B, and C nonspecific bacterial acid phosphatases., Competing Interests: The authors have declared that no competing interests exist.

Objective: To evaluate thermal nociceptive thresholds (TNTs) before and after inducing a standardized radiocarpal bone osteochondral fracture (OCF) in horses., Study Design: Prospective, controlled, randomized, masked study., Animals: A group of 10 Thoroughbred fillies aged 2 years., Methods: Skin temperature and TNTs were measured on the skin over the triceps brachii muscle in both the thoracic limbs before (week 0) and weekly (weeks 1-8) after unilateral arthroscopic induction of a radiocarpal OCF (n = 4) or sham surgery (n = 6) followed by a standardized exercise programme. The contralateral, non-operated thoracic limb was used as a control within each horse. Percentage thermal excursion (%TE) defined as %TE = 100 ∗ (TNT - skin temperature)/(cut-off temperature - skin temperature) was calculated. Data were analysed with a mixed-effects model followed by Dunnett's and Tukey's tests for within and between-limbs comparisons, respectively; p < 0.05 was considered significant., Results: Skin temperature in the control limb of OCF horses was significantly higher at week 7 than at week 0 (p = 0.0125). At week 1, TNTs and %TE values in operated limbs of OCF horses were significantly reduced compared with their baseline values at week 0 (p ≤ 0.0153) and their values in contralateral control limbs (p ≤ 0.0024) and operated limbs of sham-operated horses (p ≤ 0.0162). At week 2, TNTs and %TE values in operated limbs of OCF horses remained significantly reduced compared with values in operated limbs of sham-operated horses (p ≤ 0.0248)., Conclusions and Clinical Relevance: Creation of an OCF in a radiocarpal bone induced transitory (<2 weeks) ipsilateral heat hypersensitivity proximal to the surgery site (skin over the triceps brachii muscle) in horses. Surgically induced OCF may cause somatosensory abnormalities consistent with secondary thermal hyperalgesia., (Copyright © 2021 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Previously, our laboratory established the role of small, noncoding RNA species , i.e. , microRNA (miRNA) including miR-135a in anti-chlamydial immunity in infected hosts. We report here chlamydial infection results in decreased miR-135a expression in mouse genital tissue and a fibroblast cell line. Several chemokine and chemokine receptor genes (including CXCL10, CCR5) associated with chlamydial pathogenesis were identified in silico to contain putative miR-135a binding sequence(s) in the 3' untranslated region. The role of miR-135a in the host immune response was investigated using exogenous miR-135a mimic to restore the immune phenotype associated with decreased miR-135a following Chlamydia muridarum (Cm) infection. We observed miR-135a regulation of Cm-primed bone marrow derived dendritic cells (BMDC) via activation of Cm-immune CD4 + T cells for clonal expansion and CCR5 expression. Using a transwell cell migration assay, we explore the role of miR-135a in regulation of genital tract CXCL10 expression and recruitment of CXCR3 + CD4 + T cells via the CXCL10/CXCR3 axis. Collectively, data reported here support miR-135a affecting multiple cellular processes in response to chlamydial infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Keck, Chambers, Yu, Cheng, Christenson, Guentzel, Gupta and Arulanandam.)

Objective: To investigate the pharmacokinetics, efficacy and convulsive dose of articaine hydrochloride in goat kids., Study Design: Experimental prospective study., Animals: A total of 18 (n = 6 animals per experiment) male Saanen goat kids (2-4 weeks old)., Methods: The study consisted of three experiments. The first determined the pharmacokinetics of articaine following intravenous administration of articaine hydrochloride (8 mg kg -1 ). The second experiment investigated the anaesthetic efficacy and pharmacokinetics following cornual nerve block using 1.5% articaine hydrochloride. Anaesthesia of horn buds was evaluated using the response to pinprick test. Non-compartmental analysis was used. The final experiment determined the convulsive dose of articaine and its corresponding plasma concentration following intravenous infusion of articaine hydrochloride (4 mg kg -1 minute -1 ). Data are shown as mean ± standard deviation., Results: The mean terminal half-life (t 1/2λz ), mean volume of distribution at steady state (Vd ss ) and mean plasma clearance (CL) of articaine following intravenous administration were 0.66 hour, 3.81 L kg -1 and 5.33 L hour -1 kg -1 , respectively. After cornual nerve block, the mean maximum plasma concentration of articaine was 587 ng mL -1 at 0.22 hour and its mean t 1/2λz was 1.26 hours. Anaesthesia of horn buds was observed within 4 minutes following cornual nerve block. The mean dose required to produce convulsions was 16.24 mg kg -1 and mean convulsive plasma concentrations of articaine and articainic acid were 9905 and 1517 ng mL -1 , respectively., Conclusions: Intravenous administration of 8 mg kg -1 of articaine hydrochloride did not cause any adverse effects. Pharmacokinetic data suggest that articaine was rapidly eliminated and cleared. Cornual nerve block using 1.5% articaine hydrochloride alleviated the response to the acute nociceptive stimulus during disbudding., Clinical Relevance: Articaine hydrochloride appears to be a safe and effective local anaesthetic for disbudding in goat kids., (Copyright © 2021 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Our objective was to identify practical indicators of calf dehydration that could be used in an industry context. Eleven healthy 4-d-old commercial dairy calves were fed 2 L of mixed colostrum, then deprived of food and water for 24 h. Total body water was determined in the fed state using the deuterium dilution method. Body weight, along with a range of behavioral and physiological variables, was recorded 1 h after feeding, then at 90-min intervals through to 24 h. Blood samples were collected at every second sampling to assess changes in plasma hemoglobin, hematocrit, and osmolality. Linear mixed-effects models were used to explore associations between hydration status (% body water) and outcome variables. All calves remained bright and alert with good suckling reflexes throughout the 24-h period. After 24 h, total body water had decreased by an average of 8.4% (standard error 1.18), consistent with mild to moderate dehydration. Skin tent return time, capillary refill time, and detectable enophthalmos were associated with hydration status. Calves with skin tent return times of 3 s or longer were 4.4 percentage points less hydrated than those with return times of less than 3 s. Similarly, a capillary refill time of 3 s or longer was associated with a 4.3 percentage point reduction in hydration compared with refill times of less than 3 s. Calves with detectable enophthalmos (≥1 mm) were 3.5 percentage points less hydrated than those without enophthalmos. The skin tent, capillary refill, and enophthalmos tests are all relatively simple to perform and, although requiring the calf to be briefly restrained, can easily be performed by a single operator. The outcome of these tests was relatively consistent, in that calves above the threshold in any test were 3.5 to 4.5% less hydrated than calves below the threshold. As such, these tests may be of practical utility to identify calves with mild to moderate dehydration in an industry setting., (© 2020, The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).)

Viruses are obligate intracellular parasites, and host cell entry is the first step in the viral life cycle. The SARS-CoV-2 (COVID-19) entry process into susceptible host tissue cells is complex requiring (1) attachment of the virus via the conserved spike (S) protein receptor-binding motif (RBM) to the host cell angiotensin-converting-enzyme 2 (ACE2) receptor, (2) S protein proteolytic processing, and (3) membrane fusion. Spike protein processing occurs at two cleavage sites, i.e., S 1 /S 2 and S 2 '. Cleavage at the S 1 /S 2 and S 2 ' sites ultimately gives rise to generation of competent fusion elements important in the merging of the host cell and viral membranes. Following cleavage, shedding of the S 1 crown results in significant conformational changes and fusion peptide repositioning for target membrane insertion and fusion. Identification of specific protease involvement has been difficult due to the many cell types used and studied. However, it appears that S protein proteolytic cleavage is dependent on (1) furin and (2) serine protease transmembrane protease serine 2 proteases acting in tandem. Although at present not clear, increased SARS-CoV-2 S receptor-binding motif binding affinity and replication efficiency may in part account for observed differences in infectivity. Cleavage of the ACE2 receptor appears to be yet another layer of complexity in addition to forfeiture and/or alteration of ACE2 function which plays an important role in cardiovascular and immune function., Competing Interests: The authors declare that there exist no relevant interests perceived or otherwise that conflict with the submission of this work., (Copyright © 2020 James P. Chambers et al.)

New Zealand deer farming centres on the production of meat and velvet antler. Velvet antler removal is a painful procedure and currently, New Zealand Animal Welfare regulations dictate surgical removal of velvet antlers under lignocaine anaesthesia. To improve our knowledge on the efficacy and duration of other local anaesthetics to mitigate pain after antler removal, it is important to accurately assess and quantify pain arising from antler removal. Therefore, the current study was designed to validate mechanical nociceptive threshold (MNT) testing using a Wagner hand-held algometer, and to apply this methodology to assess the efficacy and duration of action of articaine for antler removal in deer. Baseline force (N) required to elicit the nociceptive response was recorded in 40 yearling male red deer on three alternate days. Ten of the 40 animals were selected for antler removal after administration of 4% articaine hydrochloride as a ring block. The duration of analgesic efficacy of articaine was assessed by algometry across 5 time points. There was a significant difference in MNTs among the three days (day 3 versus day 1 ( p < 0.0001), day 2 versus day 1 ( p < 0.0001), and day 1 versus day 2 ( p < 0.01)). Positive correlations were observed between weight, antler length and thresholds. The MNT values remained above 20N for 6 h after removal of velvet antlers under the articaine ring block. This study provides valuable information about the use of MNT in red deer. These findings lay a foundation for future studies in the topics of peri-operative and postoperative pain management in deer antler removal, and a possible alternative use for articaine.

Our laboratory has investigated the role of an evolutionarily conserved RNA species called microRNAs (miRs) in regulation of anti-chlamydial protective immunity. MiRs including miR-155 expressed in specific immune effector cells are critical for antigen specific protective immunity and IFN-γ production. Using miR-155 deficient mice, and a murine pulmonary model for chlamydial infection, we report here 1) the effect of host miR-155 on bacterial burden, and 2) identify probable immune genes regulated by miR-155., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2020 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Acinetobacter baumannii , a Gram-negative coccobacillus, has become a prevalent nosocomial health threat affecting the majority of hospitals both in the U.S. and around the globe. Microbial cell surface hydrophobicity (CSH) has previously been correlated with virulence, uptake by immune cells, and attachment to epithelial cells. A mutant strain of A. baumannii (ΔtrxA) lacking the redox protein thioredoxin A was found to be more hydrophobic than its wild type (WT) and complemented counterparts, as measured by both Microbial Adhesion to Hydrocarbon (MATH) and salt aggregation. The hydrophobicity of the mutant could be abrogated through treatment with sodium cyanoborohydride (SCBH). This modulation correlated with reduction of disulfide bonds, as SCBH was able to reduce 5,5'-dithio-bis-[2-nitrobenzoic acid] and treatment with the known disulfide reducer, β-mercaptoethanol, also decreased ΔtrxA CSH. Additionally, the ΔtrxA mutant was more readily taken up than WT by J774 macrophages and this differential uptake could be abrogated though SCBH treatment. When partitioned into aqueous and hydrophobic phases, ΔtrxA recovered from the hydrophobic partition was phagocytosed more readily than from the aqueous phase further supporting the contribution of CSH to A. baumannii uptake by phagocytes. A second Gram-negative bacterium, Francisella novicida , also showed the association of TrxA deficiency (FnΔtrxA) with increased hydrophobicity and uptake by J774 cells. We previously have demonstrated that modification of the type IV pilus system (T4P) was associated with the A. baumannii ΔtrxA phenotype, and the Francisella FnΔtrxA mutant also was found to have a marked T4P deficiency. Interestingly, a F. novicida mutant lacking pilT also showed increased hydrophobicity over FnWT. Collective evidence presented in this study suggests that Gram-negative bacterial thioredoxin mediates CSH through multiple mechanisms including disulfide-bond reduction and T4P modulation., (Copyright © 2019 May, Yu, Shrihari, Seshu, Klose, Cap, Chambers, Guentzel and Arulanandam.)

Spontaneous and oxytocin induced contractile activity was quantified in the bicornuate uteri of pregnant rabbits maintained in situ , using data from two- and uni- dimensional video spatiotemporal maps (VSTM) of linear and area strain rate and compared statistically. Spontaneous contractions occurred over a range of frequencies between 0.1 and 10 cpm, in gravid animals at 18-21 and at 28 days of gestation, and propagated both radially and longitudinally over the uterine wall overlying each fetus. Patches of contractions were randomly distributed over the entire surface of the cornua and were pleomorphic in shape. No spatial coordination was evident between longitudinal and circular muscle layers nor temporal coordination that could indicate the activity of a localized pacemaker. The density and duration of contractions decreased, and their frequency increased with the length of gestation in the non-laboring uterus. Increasing intravenous doses of oxytocin had no effect on the mean frequencies, or the mean durations of contractions in rabbits of 18-21 days gestation, but caused frequencies to decrease and durations to increase in rabbits of 28 days gestation, from greater spatial and temporal clustering of individual contractions. This was accompanied by an increase in the distance of propagation, the mean size of the patches of contraction, the area of the largest patch of contraction and the overall density of patches. Together these results suggest that progressive smooth muscle hypertrophy and displacement with increasing gestation is accompanied by a decrease in smooth muscle connectivity causing an increase in wall compliance and that oxytocin restores connectivity and decreases compliance, promoting volumetric expulsion rather than direct propulsion of the fetus by peristalsis. The latter effects were reversed by the β2 adrenergic receptor agonist salbutamol thus reducing area of contraction, and the duration and distance of propagation., (Copyright © 2019 Hulls, Lentle, Chua, Suisted, King, Chagas, Chambers and Stewart.)

Although manual enumeration of Chlamydia inclusion forming units is the most widely accepted means of quantification in the field, it is both time consuming and subject to inherent investigator bias. We report here a rapid, i.e ., minutes vs . hours, modified automated Fluorospot means of assessment that is linear (<1200 dots per well). Because the Fluorospot enumerated tissue culture plate/well can also be quantified using traditional manual counting, newly derived Fluorospot data can easily be compared to previously established manual enumeration data requiring no new reference norms. •Concurrent enumeration of chlamydial IFU using automated and manual methods of counting on same tissue culture plate.•Rapid method of counting chlamydial IFU reducing time from hours to minutes., Competing Interests: Authors declare that they have no competing interests.