New Zealand veterinary journal最新文献

Case history: A gland of a cow with a high somatic cell count (385,000 cells/mL at 116 days in milk) was enrolled in a therapeutic subclinical mastitis study following a positive pre-enrolment culture. One week later, the quarter was treated with 1 g of procaine penicillin on three occasions, 12 hours apart (Day 0 and 1). A further milk sample was obtained from the quarter on Days 6, 14, and 21 after initiation of treatment.

Clinical findings: Milk samples were submitted for routine bacteriological culture and matrix-assisted laser desorption/ionised time-of-flight mass spectrometry (MALDI-TOF) analysis. A Gram-negative motile rod was isolated from all samples which could not be speciated using the laboratory's standard panel of biochemical tests. The isolates were identified by MALDI-TOF as Bordetella bronchiseptica. Whole genome sequencing and comparison with publicly available genomic sequences showed that the bovine isolate did not cluster with any previously published B. bronchiseptica sequences.

Diagnosis: Subclinical mastitis caused by infection with Bordetella bronchiseptica.

Clinical relevance: Only one other case report could be found of this organism being identified in milk samples. Greater use of advanced identification systems will likely increase the number of organisms identified from mastitic milk samples. Appropriate identification is important to aid decision-making as, given the response to therapy and laboratory findings, there is a poor likelihood of bacteriological cure with beta-lactam therapy for this organism.

Case history: Three human leptospirosis cases from a case-control study were recruited for in-contact animal and environment sampling and Leptospira testing between October 2020 and December 2021. These cases were selected because of regular exposure to livestock, pets, and/or wildlife, and sampling was carried out on their farms or lifestyle blocks (sites A-C), with veterinarians overseeing the process for livestock, and cases collecting environmental and wildlife samples.

Laboratory findings: Across the three sites, a total of 137 cattle, > 40 sheep, 28 possums, six dogs, six rats, three pigs and three rabbits were tested. Herd serology results on Site A, a dairy farm, showed infection with Tarassovi and Pomona; urinary shedding showed Leptospira borgpetersenii str. Pacifica. Animals were vaccinated against Hardjo, Pomona and Copenhageni. The farmer was diagnosed with Ballum. On Site B, a beef and sheep farm, serology showed infection with Pomona; animals were not vaccinated, and the farmer was diagnosed with Hardjo. On Site C, cattle were shedding L. borgpetersenii; animals were not vaccinated, and the case's serovar was indeterminate. Six wild animals associated with Sites A and C and one environmental sample from Site A were positive for pathogenic Leptospira by PCR.

Conclusion: These findings highlight the complexity of potential exposures and the difficulty in identifying infection sources for human cases. This reinforces the need for multiple preventive measures such as animal vaccination, the use of personal protective equipment, pest control, and general awareness of leptospirosis to reduce infection risk in agricultural settings.

Clinical relevance: Farms with unvaccinated livestock had Leptospira infections, highlighting the importance of animal vaccination. Infections amongst stock that were vaccinated emphasise the importance of best practice vaccination recommendations and pest control.

Aims: To use a narrative inquiry approach to explore animal owner experiences and feelings during engagement with veterinary services with the goal of understanding what a "good experience" looks and feels like from a client perspective.

Methods: Semi-structured interviews were conducted with 30 animal owners, primarily companion animal owners of New Zealand European ethnicity, via video call or telephone. Interviews were transcribed and analysed using inductive thematic analysis.

Results: The participants narrated both positive and negative experiences with veterinary professionals, the impacts of those experiences and subsequent actions by the client. Four main themes emerged. The first identified features of the practice, beyond the standard provision of veterinary services, that had attracted participants, e.g. specific services offered. The next theme concerned the overall experience for the participants, where clients felt welcomed and cared for at all stages of the interaction. The third theme focused on building and maintaining quality relationships. We found that the principles of relationship-centred care apply and that when these factors were absent, conflict appeared more likely. The fourth theme considered factors that impacted the client-veterinary professional relationship. Our findings suggest that clients were more forgiving of poor outcomes if there was a good match and a strong existing relationship between the veterinary clinic and the client, and if the poor outcome was managed well by the veterinary practice. Managing poor outcomes well was strongly aligned with having honesty and integrity.

Conclusions: The narratives provided insights into client experiences and what is important to them when seeking animal healthcare in terms of the features that a specific veterinary practice offered them and the connections with the personnel at the veterinary practice. Relationship-centred care was key but required a good client fit to the practice to begin with.

Clinical relevance: The themes outlined in this article offer a framework for veterinary practices to assess their current performance against client priorities. By identifying areas for improvement, practices can develop plans to enhance both client satisfaction, and staff and overall practice well-being.

This review summarises up-to-date research on the diagnosis of gastrointestinal nematode (GIN) infection in livestock and anthelmintic resistance in GIN. It was commissioned to assist funding bodies to prioritise and guide research and extension efforts to improve the health, welfare and productivity of grazing ruminants in the face of challenge with GIN. A comprehensive review of published articles from journals, books and websites was undertaken, with a focus on peer-reviewed articles published between 2000 and 2024 involving genera of GIN in grazing sheep and cattle with economic importance to New Zealand. Suggestions for articles to include were received from 14 experts in GIN diagnostics. This review is a summary of a longer report submitted to the sponsoring organisation. Clinical signs of GIN infection in grazing ruminants in temperate grazing systems are inadequate as triggers for management interventions including anthelmintic treatment as they are visible only after economically significant pathological changes have occurred. Livestock producers benefit from monitoring GIN burdens using faecal egg counts (FEC) or associated signals such as weight gain. In future, they may use remote monitoring devices for activity in animals, as well as estimating pasture larval contamination. Methods of diagnosing GIN infections using automated FEC devices have improved the convenience of monitoring parasite burdens compared with traditional laboratory methods. However, a lack of quality control measures and a gap in training of skilled technicians for larval differentiation may lead to a shortage of diagnostic capability. Current methods of diagnosing anthelmintic resistance, particularly FEC reduction tests, are not likely to be replaced by laboratory assays in the near future and attention should be focused on facilitating application of new FEC technologies for both animal monitoring and resistance diagnosis. Extension and application of currently available methods and technology will improve animal health and productivity in ruminant grazing systems in the short term. Adoption of novel technologies for remote animal monitoring, practical tools for estimating pasture larval contamination and promoting genetic selection for immunity and resilience to GIN in both sheep and cattle will further enhance productivity in the long term.

Case history: In early summer, a wild fledgling kererū (Hemiphaga novaeseelandiae) was admitted to a wildlife hospital in Dunedin after falling from its nest and being found on the ground.

Clinical findings: The bird was underweight, weighing only 391 g (expected weight > 450 g), and determined to be in poor body condition based on palpation of pectoral muscle mass. There was bilateral periorbital swelling and ocular discharge with caseous material blocking the choana. Samples of the ocular and choanal discharge were collected and submitted for molecular testing. General anaesthesia was required for further radiographic assessment, and the bird was stabilised for 48 hours with oral electrolytes and antimicrobial and analgesic therapy with doxycycline, meloxicam, and tramadol administered orally twice daily via crop tube and voriconazole administered once daily. Chloramphenicol was applied topically to the eyes twice daily. Subsequently, due to the severity of the gross and radiographic lesions, the likelihood of the need for an extended period of treatment, the age of the chick, its weakened and underweight condition and the risk of imprinting, the bird was euthanased while under general anaesthesia.

Laboratory and pathological findings: PCR testing ruled out Chlamydia psittaci as a cause of morbidity and instead identified Mycoplasma columborale. On gross post-mortem examination, there was caseous material in the periorbital tissues, sinuses and choana. Samples of the choanal discharge grew a moderate mixed growth of Escherichia coli and Enterococcus faecalis.

Diagnosis: Severe pyogranulomatous sinusitis associated with infection with M. columborale.

Clinical relevance: This report describes the first isolation of M. columborale in any species in New Zealand and the first diagnosis of mycoplasmosis in a native kererū. The significance of this finding has not yet been determined.

Aims: To describe progress in the reduction of the consumption of antimicrobial drugs by food-producing animals in New Zealand to 2022 and to identify the animal production sectors where progress has been greatest, and those where opportunities remain.

Methods: Data were sourced from official government and industry reports to update previous estimates of consumption (as sales) of antimicrobial products applied to food-producing animals in New Zealand, European countries and the USA. Antimicrobial consumption (AMC) was estimated based on the amount of active ingredient sold, per kg of animal biomass standardised to the probable weight at time of treatment or lifetime mean weight but not slaughter weight (population correction unit; PCU). This methodology is widely used for international comparisons.

Results: The estimated gross consumption of antimicrobials in food-producing animals in New Zealand increased steadily from 2005 to 2013 (from 7.54 to 11.28 mg/PCU). From 2014 to 2018 the estimate flattened to a 5-year rolling mean of 10.40 mg/PCU. In 2019-2021 the consumption dropped. The NZ consumption in 2022 was substantially lower, estimated at 5.84 mg/PCU, 29% less than in 2005 and 45% less than the peak that occurred in 2017.

Conclusions: The use of antimicrobials in food-producing animals in New Zealand is at the lowest rate for nearly 20 years, at 5.8 mg/PCU. Key progress has been made particularly by the poultry industry. Clear future areas to be targeted include prophylactic use of intramammary products applied when drying off dairy cows and a more widespread strategic use in treatment of clinical mastitis.

Clinical relevance: Veterinarians in New Zealand should leverage the significant reduction achieved in AMC by food-producing animals by continuing to improve strategies for antimicrobial use to further reduce the risk of antimicrobial resistance.

Case history: A 9-year-old, spayed, female Golden Retriever presented with an 18-month history of small spots of opacification on the left cornea, a 3-4-month history of a raised spot on the left cornea, and a watery left eye. As a puppy, the dog had sustained an injury to the left cornea. Self-limiting, presumed papillomaviral warts were diagnosed on the face when the dog was 8 months old.

Clinical findings and initial treatment: A full ophthalmic examination revealed a well-circumscribed, pigmented, raised mass immediately adjacent to three smaller pink masses on the left cornea. The corneal tumour was resected by superficial keratectomy. The cornea was treated with topical peginterferon alfa-2a drops post-operatively.

Pathological and molecular findings: The mass was histologically diagnosed as an incompletely excised corneal pigmented squamous cell carcinoma (pSCC) displaying both exophytic growth and superficial stromal invasive characteristics and fine granular brown melanin pigment within the cytoplasm of neoplastic cells. Superficial cells showed evidence of papillomavirus-induced cell changes including enlarged cells with blue-grey cytoplasm and darkly basophilic keratohyalin granules. Canine papillomavirus type 17 (CPV17) DNA sequences were amplified from the carcinoma by PCR using consensus papillomavirus primers.

Diagnosis: Primary corneal pigmented squamous cell carcinoma with concurrent canine papillomavirus type 17 infection.

Outcome: Tumour recurrence was observed 2 years 9 months after surgery. Topical peginterferon alfa-2a drops were recommenced and superficial keratectomy surgery was repeated with concurrent adjunctive strontium 90 plesiotherapy. At the time of writing, the left cornea has healed well with mild fibrosis and vascularisation continuing to reduce.

Clinical relevance: This is the first report of a pSCC of the cornea in any veterinary species. Prominent papillomaviral cytopathology was visible in the corneal pSCC, and PCR confirmed the presence of CPV17.This report expands the differential diagnoses for pigmented corneal masses in dogs. It highlights the importance of obtaining a histopathological diagnosis for pigmented corneal lesions, as the clinical disease course, prognosis and treatment options vary between lesions of different aetiologies. Corneal SCC is locally invasive and can recur without complete excision. Early surgical intervention with clean margins can be curative and restore corneal clarity, vision and patient comfort.

Aims: To determine the genetic makeup of carnivore parvoviruses currently circulating in New Zealand; to investigate their evolutionary patterns; and to compare these viruses with those detected during the previous New Zealand-based survey (2009-2010).

Methods: Faecal samples from dogs (n = 40) with a clinical diagnosis of parvovirus enteritis were voluntarily submitted by veterinarians from throughout New Zealand. In addition, one sample was collected from a cat with comparable clinical presentation. The samples were used for DNA extraction and PCR amplification of viral protein 2 (VP2) of canine parvovirus type 2 (CPV-2). All samples produced amplicons of the expected sizes, which were then sequenced. The viruses were subtyped based on the presence of specific amino acids at defined locations. In addition, VP2 sequences were analysed using phylogeny and molecular network analysis.

Results: The majority (30/40; 75%) of CPV-2-infected dogs were younger than 6 months and 8/40 (20%) were aged between 9 months and 1 year. Most (39/41; 95%) parvoviruses were subtyped as CPV-2c, and one as the original CPV-2. The faecal sample from a cat was positive for feline panleukopenia virus. The majority (37/39; 95%) of New Zealand CPV-2c viruses were monophyletic. The remaining two New Zealand CPV-2c viruses clustered with Chinese and Sri Lankan CPV-2c viruses, separately from the main New Zealand clade.

Conclusions: There has been an apparent replacement of the CPV-2a viruses with CPV-2c viruses in New Zealand between 2011 and 2019. The source of the current CPV-2c viruses remains undetermined. The monophyletic nature of the majority of viruses detected most likely reflects a country-wide spread of the most successful genotype. However, an occasional introduction of CPV-2 from overseas cannot be excluded.

Clinical relevance: Current vaccines appear to be protective against disease caused by the CPV-2c viruses currently circulating in New Zealand. Vaccination and protection from environmental sources of CPV-2 until the development of vaccine-induced immunity remains the cornerstone of protection in young dogs against parvovirus enteritis. Ongoing monitoring of the genetic changes in CPV-2 is important, as it would allow early detection of variants that may be more likely to escape vaccine-induced immunity.

Case history: In April and June of 2024, two outbreaks of photosensitisation occurred in a herd of 354 beef cows and calves in Buenos Aires province, Argentina. Both outbreaks occurred in the same paddock, where red clover (Trifolium pratense) was the dominant pasture species, combined with tall fescue (Schedonorus arundinaceus, previously Festuca arundinacea), white clover (T. repens), bird's foot trefoil (Lotus corniculatus), and perennial ryegrass (Lolium perenne).

Clinical findings: Signs of head tilt, restlessness, tail swishing, and searching behaviour for shade and water were first observed 15-19 days after grazing, with skin necrosis and eyelid inflammation visible on closer examination. A cumulative incidence of 5.6% and 10.7% was recorded in each outbreak with all animals recovering 5-10 days after removal to a paddock composed of wheatgrass (Triticum aestivum) and Festuca spp.

Laboratory and pathological: Following the second outbreak, nine serum samples and seven ear skin biopsies were collected from affected animals for assessment of hepatic enzyme activities and histopathology, along with a pasture sample to assess the spore count for Pithomyces chartarum. Serum activity levels of glutamic oxaloacetic transaminase (GOT) and gamma-glutamyl transferase (GGT) were normal in nine and four affected cows, with slightly elevated GGT activities in the remaining five cows. Activities of all other liver enzymes were within normal limits and there was no sign of icterus. Histological examination of the ear skin biopsies revealed necrotising dermatitis and epidermal hyperplasia compatible with photosensitisation. The spore count for P. chartarum was low (11,250 spores/g fresh pasture).

Diagnosis: The epidemiological data, clinical presentation and clinical-pathology findings suggest that these cows were affected by primary photosensitisation most probably due to the ingestion of T. pratense.

Clinical relevance: Identifying a plant species as a cause of primary photosensitisation is difficult, and the aetiological agent often remains unidentified. The association between consumption of a sward containing T. pratense and the photosensitisation reported in this study suggests that this plant species may be acting as a primary cause of photosensitisation in cattle. This study highlights the need for further research to identify toxic elements in T. pratense and their effects on livestock.

Objectives: This systematic review aims to describe and understand the evidence available for commonly recommended management strategies for feline idiopathic cystitis (FIC) to provide guidance for clinicians in their treatment of this condition. A subsequent objective was to identify gaps in the literature and areas where future research may be directed.

Methods: A computerised search of three electronic databases (Discover, Scopus and PubMed) was performed. Results were imported into a single EndNote library and duplicates were removed. Remaining records underwent a two-stage screening process with the aim to identify peer-reviewed primary literature on therapeutic strategies for FIC. Studies were categorised according to one of seven management strategies: environmental modification, dietary manipulation, anti-inflammatory drugs, amitriptyline, glycosaminoglycans, prazosin, and intravesical lidocaine.

Results: Twenty-two studies were included in the final review, with one study providing evidence in two categories. Two studies assessed environmental manipulation, with results showing encouraging evidence for multimodal environmental modification but little evidence to support the use of feline facial pheromone. Five papers examined dietary manipulation, with good evidence for the use of therapeutic urinary diets, and for increasing the moisture content of a cat's diet. Anti-inflammatory drugs were the focus of four studies, with none providing evidence to support their use. Four papers indicated that the evidence to support glycosaminoglycans is lacking. The antispasmodic drug prazosin was purported to be useful in one retrospective paper, while three papers comparing it to a placebo showed no evidence for its use. Three studies assessed amitriptyline, with two indicating that short-term use is not supported, and one long-term study suggesting it may be useful in some refractory cases. One study on intravesical instillation of lidocaine concluded that it was not a useful treatment strategy.

Conclusions: Multimodal environmental modification to reduce stress/conflict and therapeutic urinary foods (particularly if combined with an increase in moisture content of the diet) currently have the strongest evidence to support their use in managing FIC, and should, together, be considered the primary treatment approach. The evidence for other modalities, is currently insufficient to support their use. The overall lack of high quality studies emphasises the need for clinicians to be critical in their evaluation of the published literature on the management of this perplexing condition.