Veterinary Record Open最新文献

Background: Canine peripheral nodal T-cell lymphoma is considered chemotherapy resistant and carries a relatively poor prognosis. Prospective evaluations reporting the impact of chemotherapy on progression-free survival (PFS) and overall survival time for dogs with T-cell lymphoma are lacking. This study examined the impact of L-CHOP (L-asparaginase, doxorubicin, cyclophosphamide, vincristine, prednisone) chemotherapy or L-CHOP in combination with AT-005, a US Department of Agriculture-licensed caninised monoclonal antibody, on PFS and response rates in dogs with clinical intermediate- and high-grade peripheral nodal T-cell lymphoma.

Methods: A prospective, randomised, placebo-controlled, investigator- and owner-blinded, multicentre study was completed. All dogs received a 19-week L-CHOP chemotherapy protocol with randomisation (1:1) into placebo or AT-005 groups. Response was evaluated via the Veterinary Cooperative Oncology Group criteria for canine lymphoma.

Results: Forty-nine dogs were enrolled (25 received placebo and 24 received AT-005). Most demographic factors were similar between the two groups, with the exception that more dogs with stage IV and V disease were treated with AT-005 (34% vs. 8%; p = 0.03). Median PFS was 103 days (95% confidence interval [CI], 56-118) in the placebo group versus 64 days (95% CI, 36-118) in the AT-005 group. The overall response rate (ORR) for all dogs was 98% (48 of 49); complete response rate in the placebo group (64%) was not different from the AT-005 group (67%).

Conclusions: To the best of the authors' knowledge, this is the first prospective study to document that treatment with L-CHOP chemotherapy, with or without AT-005, may result in a high ORR, but relatively brief PFS in dogs with clinical intermediate- and high-grade T-cell lymphoma.

Background: Burden transfer, when veterinary client caregiver burden underlies stressful encounters with providers, elevates risk for occupational distress in veterinary medicine. To date, burden transfer has been primarily examined in veterinarians working in general practice, using methods that are time consuming. The current work validates an abbreviated Burden Transfer Inventory (BTI-A) and explores burden transfer across positions of employment and veterinary settings.

Methods: Participants completed online measures of burden transfer, stress and burnout. A BTI-A with items representing each BTI domain was created with an initial validation sample (n = 1151 veterinarians). Confirmatory psychometric analyses were conducted in a cross-validation sample (n = 440 veterinarians and support staff), followed by exploration of the BTI and BTI-A across veterinary settings and position of employment.

Results: The BTI-A correlated with the full-length BTI (r = 0.89-0.96) shows good internal consistency (α = 0.72-0.88) and 1-month test-retest reliability (r = 0.69-0.74). The BTI-A correlated significantly (p < 0.001) with stress and burnout. Exploratory comparisons suggested group differences including greater reactivity in general compared to specialty referral/emergency practice (p = 0.02).

Conclusion: The BTI-A can be used in place of the original measure when brevity is important. Use of the BTI-A may help guide allied mental health professionals in providing support for wellbeing in veterinary healthcare team members.

Background: Hormonal replacement therapy is widely used to treat conditions in humans, the most well-known indication being the relief of menopausal symptoms in women. Many of the hormone-containing products (HCP) are applied to the skin. This transdermal delivery poses a risk to animals and humans through secondary exposure, especially when product information is not strictly followed. The aim of this article is to raise awareness among veterinarians and human healthcare providers of this risk; based on evidence from spontaneous reporting of suspected adverse events (AEs) in animals and humans. Interventions are also explored to mitigate the risk of secondary exposure to transdermal HCP (THCP).

Review of spontaneously reported suspected aes: The Swedish Medical Products Agency has received several, mainly serious, AE reports in animals and children following secondary exposure to THCPs. The AE reports were reviewed together with worldwide data from the EudraVigilance Veterinary database and human EudraVigilance Data Analysis System. The clinical signs reported in animals included persistent signs of oestrus, poor growth rate and birth defects. In humans, reported clinical signs included precocious puberty, unresolved virilisation, accelerated growth rate and female infertility.

Conclusions: It is important that THCP are used according to manufacturer's instructions and users are made aware of risks and mitigating measures. This review of AEs in animals and children provides evidence to show that the use of THCP poses a risk for secondary exposure. Efficient communication strategies that stretch across veterinary and human medicinal disciplines are required to raise mutual awareness and minimise the risk of AEs in animals and humans.

Objective: The Gram-negative bacterium Actinobacillus suis is an agent of global importance to the swine industry and the cause of lethal respiratory or septicaemic disease in pigs of different ages. Between 2018 and 2019, seven commercial farms in western Canada experienced episodes of increased mortality due to A. suis infection in grower pigs. The goal of this work was to profile, with molecular methods, A. suis isolated from diseased pigs and to compare them to other isolates.

Design: This inferential observational study used nine western Canadian strains obtained from diseased lungs (n = 6), heart (n = 2) and brain (n = 1) and whole genome sequencing was performed. Comparative genomic analyses were performed to characterise the genetic variability, antimicrobial resistance and the virulence genes present.

Results: Compared to the reference strain (ATCC 33415), an increased number of RTX (repeats in the structural toxin) gene copies were identified in strains isolated from organs without a mucosal surface, thus theoretically harder to invade. Western Canadian strains did not harbour genes associated with resistance to antimicrobial agents used in swine production. Novel regions were also identified in the genomes of five of nine strains demonstrating recombination and emergence of novel strains.

Conclusions: The results obtained in this study were associated with the emergence of new lineages. An increased number of RTX toxin gene copies is suggested to be associated with increased virulence. This study will contribute to improve our understanding regarding A. suis and may help guide vaccine development and agent control measures.

Background: Thoroughbred breeders aim to have foals born early in the season, but scientific evidence on the advantages for race performance is scarce and contradictory.

Methods: The association between date of birth and purchase price as foal/yearling, with race performance by the end of the second and third years of life of Thoroughbreds racing in flat races in the United Kingdom (UK) and Ireland (IRE) was assessed using negative binomial and zero-inflated negative binomial models on the entire 2014-2015 UK/IRE foal crops (n = 28,282).

Results: In total, 6666 and 9456 horses raced in UK/IRE flat racing by the end of their second and third years of life. Prize money and prize money per start decreased with each additional day beyond 1 January that the foal was born. Purchase price as foal and yearling was negatively associated with the number of races run, while it was positively associated with prize money and prize money per start by the end of the third year of life.

Conclusions: Foals born early in the season had higher earnings by the end of their second and third years of life than foals born later. Differences were more marked among males than females. The most expensive horses sold as foals or yearlings ran fewer races but earned more prize money and prize money per start than less expensive horses. Results from this population-based analyses may inform strategies and management practices aiming to maximise horses' racing performance potential and increase financial returns.

Background: Reducing the age at first calving (AFC) in dairy heifers may decrease replacement costs, while the acceleration of body growth could affect milk productivity. A lower bodyweight (BW) at first calving may increase calving problems and compromise the subsequent reproductive performance.

Materials and methods: This retrospective study aimed to investigate the effect of AFC and BW prior to calving on milk productivity, the incidence of calving problems (difficult calving and stillbirth) and reproductive performance during the first lactation. Multivariate analysis was conducted using a total of 203 calving records from 1999 to 2012 for one herd of Holstein heifers. The AFC was categorised as young, moderate, old and very old (<22.5, 22.5 to <24.0, 24.0 to <25.5, ≥25.5 months) and the heifer BW before first calving was grouped into low, moderate, high and very high (≤625, 626-654, 655-683, ≥684 kg), respectively.

Results: The incidence of difficult calving and the prevalence of stillbirth were significantly higher in the animals with low BW compared with the heifers with moderate and high BW. Even so, there was no adverse impact on reproductive performance. There was a significant association between the lifetime daily milk yield and AFC; the highest mean value for yield was recorded for the heifers in the young AFC group, which was significantly different from heifers in the moderate and old age groups.

Conclusions: In this experimental herd, a reduction in AFC could increase the profitability during the first lactation.

Introduction: Hyperbilirubinaemia is an important clinicopathological finding in canine medicine. The objectives of this study were to describe the clinical presentation and outcome of dogs with hyperbilirubinaemia; also to identify factors associated with survival.

Materials and methods: Retrospective study of dogs with hyperbilirubinaemia from two referral centres in South Australia (2015-2020). Signalment, clinical signs, clinicopathological data, diagnosis and outcome were obtained from searching clinical records. Univariable analysis and logistic regression modelling were used to compare outcomes and overall survival.

Results: A total of 115 cases were included. The most common clinical signs were vomiting (63.5%), anorexia (62.6%), lethargy (55.7%) and pyrexia (18.3%). Pre-hepatic icterus was diagnosed in 18 cases (15.7%), hepatic icterus in 51 cases (44.3%) and post-hepatic icterus in 42 cases (36.5%). The median survival time across all cases was 40 days (95% confidence interval [CI]: 9-126 days). There was an increased risk of death in dogs with serum bilirubin greater than 60 μmol/L at diagnosis (odds ratio [OR] = 3.55; 95% CI: 1.53-8.22; p-value = 0.003) and in dogs with pre-hepatic icterus compared to hepatic (OR = 4.35; 95% CI: 1.18-16.0; p-value = 0.027) and post-hepatic icterus (OR = 6.52; 95% CI: 1.67-25.5; p-value = 0.007).

Conclusions: Pre-hepatic icterus was associated with a significantly higher risk of death than hepatic and post-hepatic icterus. Serum bilirubin >60 μmol/L at diagnosis was associated with a significantly shorter median survival time. This cut-off may be useful in discussions with owners regarding pursuing further diagnostic investigation and treatment. Further prospective studies are needed to prove the validity of this cut-off.

Background: Meticillin-resistant Staphylococcus pseudintermedius (MRSP) infections in companion animals are increasing and are difficult to treat. Environmental contamination with MRSP in small animal primary care hospitals may pose an exposure risk to animal patients.

Methods: This longitudinal study assessed the genotypic relationships of MRSP isolated from 39 environmental samples collected from six private small animal primary care hospitals, in the north-eastern United States, between August 2018 and April 2019.

Results: Of the 39 bacterial isolates, 18 unique pulsotypes were identified based on pulsed-field gel electrophoresis, including six clusters of two or more indistinguishable isolates. Single pulsotypes were frequently detected from multiple hand-contact and animal-contact surfaces within a hospital during a single sampling event, but detection of a single pulsotype within the same hospital on subsequent visits was infrequent. However, one pulsotype was recovered from three separate hospitals, which suggests that either MRSP transmission between hospitals may have occurred via people, animals, or fomites or that there was a dominant community strain.

Conclusions: Single strains of MRSP were isolated from various hand-contact and animal-contact surfaces within hospitals, indicating the important role of humans, animals and the environment in MRSP transmission. Additionally, the detection of a single strain between hospitals and over time suggests that either MRSP transmission between hospitals may have occurred via people, animals or fomites or that there was a dominant community strain.

Background: Nonesterified fatty acids (NEFAs) are an important energy substrate in mammals. Measurement of the NEFA concentration in blood serum is common practice and enables reliable detection of a negative energy balance in several species. This parameter can be used to detect subclinical metabolic diseases or to optimise feeding to prevent severe negative energy balance. Since no reference values for dogs have been published, the aim of this study was to establish such values.

Methods: Blood serum from 85 healthy dogs was examined with a multiparameter clinical chemistry analyser. Given that NEFA values are not usually normally distributed, reference intervals (RIs) were calculated nonparametrically using bootstrapping (5000 replicates) for the 90% confidence intervals.

Results: The examined cohort had a median age of 62.16 months (2-180 months) and a median weight of 19.2 kg (3.0-55.0 kg) and comprised 27 (31.8%) males and 58 (68.2%) females, with 32 (37.6%) neutered or spayed. The fasting time was 5.9 h (range 0-23 h). The tested confounders age, sex, neuter status, bodyweight and body condition score did not significantly affect the NEFA concentrations.

Conclusions: The NEFA RI for dogs in this study was 0.2-1.47 mmol/L. The results may be used to adjust food composition and amount in healthy dogs or to detect metabolic disorders. Further research on NEFA metabolism in dogs maintained in standardised conditions and in specific nutritional situations or with particular diseases is warranted.

Background: Schmallenberg virus (SBV) is a midge-borne arbovirus that first emerged in the European ruminant population in 2011 and has since settled to an endemic pattern of disease outbreaks on an approximately 4-year cycle when herd immunity from the previous circulation drops to a point allowing renewed widescale virus circulation. The impacts of trade restrictions on genetic products (semen, embryos) from affected areas were severe, particularly after the discovery that the virus is intermittently shed in the semen of a small number of bulls. The trade in small ruminant (ram and goat) semen is less than that of bulls; nonetheless, there has been no study into the shedding rate of SBV in ram semen.

Methods: Semen samples (n = 65) were collected as part of UK ram trials and artificial insemination studies around the period of the 2016-2018 SBV recirculation. Semen was preserved in RNAlater for shipping, and RNA extraction with RNeasy and S gene RT-quantitative PCR performed for SBV nucleic acid detection.

Results: No SBV RNA was detected in any samples.

Conclusions: While larger numbers of animals would be needed to completely exclude the possibility of SBV shedding in ram semen, this trial nonetheless highlights that this is likely a rare event if it occurs at all and is unlikely to play a role in disease transmission.