New Zealand veterinary journal最新文献

Aims: To develop a structured process for a transparent, efficient, high-level review of a low-resource biosecurity system (limited by physical infrastructure, financial, and human resources), in order to identify and prioritise key areas for future focus which could then lead to interventions, tailored by country, to improve the system. A key requirement was that the approach developed was culturally sensitive and respectful to Pasifika people within the country.

Methods: Animal health and biosecurity systems need to be urgently strengthened by Pacific Island countries and territories (PICTs) if they are to respond to current and future threats. Understanding where additional resources should be allocated to maximise benefit and ensuring buy-in from PICT stakeholders are critical for uptake of any recommendations made. However, there is little available literature on reviewing biosecurity systems, particularly where there is a need for efficiency, simplicity, and cultural sensitivity. A framework was developed through initial in-person consultation between four New Zealand experts who had experience working in international animal health development and support programmes. This was followed by input from informal discussions with selected heads of agriculture in PICTs and included their experiences with previous system reviews, as well as general advice from experts in Pasifika culture. Foundational objectives included simplicity, local inclusivity, and a structured approach, which could be undertaken over a relatively short period of time.A rapid evidence assessment methodology was used to search the available literature (published and grey, search terms biosecurity, system, Pacific, animal, framework, and review used in AND/OR combinations), to establish an evidence base for other methods of biosecurity system review. The developed framework for review of biosecurity systems in low-resource PICTs was based on elements from expert elicitation frameworks, the SurF surveillance evaluation framework and the Performance of Veterinary Services tool from The World Organisation for Animal Health.

Results: The developed framework involved bringing stakeholders together in a workshop environment and comprised up to 10 steps including mapping the PICT biosecurity system and exploring attributes of component activities. Understanding the system at a high level enables stakeholders to make informed recommendations on improvements to address future needs. Using the Delphi method, recommendations were then prioritised by stakeholders.

Conclusions and clinical relevance: A distinctive difference flowing from the use of the needs analysis described in this process was the empowerment of PICT stakeholders to determine their own needs and priorities, rather than have these developed by external parties.

Aims: To investigate the association between gastrointestinal parasites (GIP) and animal behaviour in dairy calves under New Zealand pastoral conditions, using animal-mounted, accelerometer-based sensors.

Methods: Thirty-six, 5-6-month-old, Friesian-Jersey, heifer calves fitted with animal activity sensors to track behaviour were randomly allocated to one of two treatment groups. Half the animals were challenged with an oral dose of 20,000 larvae of Ostertagia ostertagi and Cooperia oncophera once a week for 3 weeks and half were unchallenged. Five weeks after the last dose, seven infected and nine uninfected animals were treated with an oral anthelmintic (AHC) and data collected for a further week. Accelerometer data were classified into minutes per day eating, ruminating, in moderate-high activity or in low activity. Live weight and faecal egg counts (FEC) were recorded weekly over the study period. All animals co-grazed a newly sown pasture not previously grazed by ruminants and were moved every week to fresh grazing. Treatment status was blinded to those managing the animals which were otherwise treated identically.

Results: Complete behavioural records were available from 30/36 calves, (13 challenged and 17 unchallenged). Before treatment with AHC, FEC increased in infected and un-treated calves over the study, while uninfected animals maintained a near zero FEC. There was no difference in live weight gain between the two groups over the study period. Bayesian, multinomial regression predicted differences in animal behaviour between infected and uninfected animals that were not treated with AHC over the 7 weeks following initial infection. Parasitised calves not treated with AHC were less active and spent up to 6 (95% highest density interval (HDI) = 1-11) minutes/day less in low level activity and up to 15 (95% HDI = 7-20) minutes/day less in moderate to high level activity. They ruminated up to 9 (95% HDI = 2-15) minutes/day more and ate up to 10 (95% HDI = 2-19) minutes/day more than control calves that were not treated with AHC. The effect of AHC on time spent in each behaviour differed between infected and uninfected calves and increased the coefficient of dispersion of the behavioural data.

Conclusions and clinical relevance: Small differences in animal behaviour can be measured in calves with GIP. However, to use this to target treatment, further validation studies are required to confirm the accuracy of behavioural classification and understand the complex drivers of animal behaviour in a dynamic and variable pasture-parasite-host environment.

Horses are exquisitely sensitive to tetanus neurotoxin and are exposed to the risk of infection with Clostridium tetani throughout life. The vaccine against tetanus is highly effective at preventing disease, whereas tetanus in unvaccinated populations is associated with high mortality rates. Current guidelines in New Zealand and Australia for the available vaccine contain contradictions and limitations surrounding the optimal tetanus immunisation protocols for both adult horses and foals. This review critically evaluates the scientific literature on tetanus prophylaxis in horses within the context of equine practice and available products in New Zealand and Australia. The review was conducted by a panel of industry and specialist veterinarians to obtain agreement on nine equine tetanus prophylaxis guidelines for practising veterinarians. The primary protocol for tetanus toxoid (TT) immunisation consists of a three-dose series IM for all horses ≥ 6 months of age, and a four-dose series IM is proposed if commencing vaccination in foals between 3 and 6 months of age. Tetanus prophylaxis in foals < 3 months of age relies on passive immunity strategies. Following the completion of the primary protocol, a TT booster dose IM should be administered within 5 years, and every 5 years thereafter. When followed, these protocols should provide adequate protection against tetanus in horses. Additional tetanus prophylaxis guidelines are provided for veterinarians attending a horse experiencing a known "risk event" (e.g. wound, hoof abscess, surgery, umbilical infection). When a correctly vaccinated horse experiences a risk event, pre-existing immunity provides protection against tetanus. When an unvaccinated horse or one with unknown vaccination status, or a foal born to an unvaccinated dam, experiences a risk event, TT IM and tetanus antitoxin (TAT) 1,500 IU SC should be administered simultaneously at separate sites, and the TT primary immunisation protocol should subsequently be completed for the horse's respective age. In previously immunised pregnant broodmares, a TT booster dose administered 4-8 weeks prior to parturition optimises the transfer of passive immunity against tetanus to the newborn foal via colostrum; provided that post-natal IgG concentration in serum is > 800 mg/dL (8 g/L), such foals should be passively protected against tetanus up to 6 months of age. Survivors of clinical tetanus must still receive the primary protocol for vaccination against tetanus. In summary, all horses in New Zealand and Australia should be vaccinated against tetanus with protection maintained throughout life via TT booster doses, facilitated by accurate medical record keeping and client education.

Aims: To compare the recovery of lambs, goats, and calves from head-only (HO) or high-frequency head-to-body stunning and evaluate the complementary use of behaviour and electroencephalography (EEG) to assess return to consciousness after electrical stunning in these species.

Methods: Six-month-old lambs, adult goats and calves (< 7 days old) were subjected to reversible head-only stunning (50 Hz, 1 A, 2 seconds) or reversible high-frequency head-to-body stunning (RHTB: HO followed by 2,000 Hz, 2 A, 4-second stun to body). Following stunning, behavioural recovery was assessed in 21 lambs, 22 goats, and 20 calves. Latencies to first perform behaviours (end of convulsions, head lift, attempt to right, successful righting, attempt to stand, successful standing) after stunning were scored from video recordings. Recovery of electrical brain activity indicative of consciousness was assessed using EEG in a separate cohort of minimally-anaesthetised lambs, goats and calves (n = 20 per species). EEG traces collected before and after stunning were classified as normal, epileptiform, isoelectric, or transitional activity. Following stunning, the duration of epileptiform and isoelectric activity combined (states of brain activity incompatible with conscious awareness) was calculated, as was latency to return of normal (pre-stun) EEG.

Results: The RHTB stun was reversible in all three species, although one sheep failed to recover and was euthanised. Both methods caused tonic and clonic convulsions in all species. Behavioural recovery of sheep and calves was similar for both methods while goats took longer to recover from RHTB than HO stunning. There was no evidence of differences between methods in the duration of EEG incompatible with consciousness or the latency to recovery of normal EEG.

Conclusions: Head-to-body stunning as applied here produced a reversible electrical stun in lambs, adult goats and young calves, although the benefits in terms of meat quality and operator safety are uncertain. Goats took longer to recover behaviourally from head-to-body stunning, possibly due to disrupted motor function, but there was no indication that post-stun unconsciousness lasted longer than following head-only stunning in any species. The normal behaviour for the animals' developmental age should be considered when deciding on behavioural indicators of recovery. The minimal anaesthesia model provided excellent quality EEG data that was valuable for interpretation of the behavioural responses.

Clinical relevance: For the purposes of pre-slaughter stunning of sheep, goats and young calves, recovery appears comparable between the two methods, with all but 1/63 animals in the behaviour study recovering normal function.

Aims: To generate a taxonomy of potentially morally injurious events (PMIE) encountered in veterinary care and develop an instrument to measure moral distress and posttraumatic growth following exposure to PMIE in the veterinary population.

Methods: Development and preliminary evaluation of the Moral Distress-Posttraumatic Growth Scale for Veterinary Professionals (MD-PTG-VP) employed data from veterinary professionals (veterinarians, veterinary nurses, veterinary technicians) from Australia and New Zealand across three phases: (1) item generation, (2) content validation, and (3) construct validation. In Phase 1 respondents (n = 46) were asked whether they had experienced any of six PMIE and to identify any PMIE not listed that they had experienced. In Phase 2 a different group of respondents (n = 11) assessed a list of 10 PMIE for relevance, clarity and appropriateness. In Phase 3 the final instrument was tested with a third group of respondents (n = 104) who also completed the Short Post-Traumatic Stress Disorder Rating Interview (SPRINT), a measure of posttraumatic stress, and the Stress-Related Growth Scale-Short Form (SRGS-SF) a measure of perceived posttraumatic growth. Spearman's correlation coefficients were calculated between respondent scores on each of the MD-PTG-VP subscales, the SPRINT, and the SRGS-SF to assess construct validity.

Results: A 10-item taxonomy of PMIE encountered in veterinary care was generated in Phase 1. Items were deemed relevant, clear and appropriate by veterinary professionals in Phase 2. These were included in the developed instrument which measures frequency and impact of exposure to 10 PMIE, yielding three subscale scores (exposure frequency, moral distress, and posttraumatic growth). Assessment of construct validity by measuring correlation with SPRINT and SRGS-SF indicated satisfactory validity.

Conclusions: The MD-PTG-VP provides an informative tool that can be employed to examine professionals' mental health and wellbeing following exposure to PMIE frequently encountered in animal care. Further evaluation is required to ascertain population norms and confirm score cut-offs that reflect clinical presentation.

Clinical relevance: Once fully validated this instrument may be useful to quantify the frequency and intensity of positive and negative aspects of PMIE exposure on veterinary professionals so that accurate population comparisons can be made and changes measured over time.

Aims: To describe the incidence, aetiology, treatment, and outcomes of farmer-reported clinical mastitis on New Zealand dairy sheep farms.

Methods: A prospective cohort study was conducted on 20 spring-lambing New Zealand sheep milking farms over the 2022-2023 season. Clinical mastitis was defined as a change in the appearance of milk and/or signs of inflammation in the gland. Farmers were required to report all cases of clinical mastitis and collect information on affected ewes' demographics, clinical features, treatments (where applicable), and outcomes. Milk samples from mastitic glands were submitted for microbiological culture and identification by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF).

Results: Partial or complete clinical mastitis data were available for 236 cases from 221 ewes on 18/20 study farms. Clinical mastitis was diagnosed in 0-6% of ewes at the farm level, with an overall incidence of 1.8 (95% CI = 1.0-3.2)% using the study data, or 2.3 (95% CI = 1.6-3.3)% using the study data and farmer estimates that included unreported cases. Cases occurred mostly in early lactation, with 59% detected during the lambing period (August-October), at a median of 7 (IQR 3, 40) days in milk. The majority of cases featured clots in the milk (59%), swelling (55%), and unevenness (71%) of the glands. Pyrexia (rectal temperature $\ge$ 40.0°C) was diagnosed in 25% of cases and depression (lethargy, inappetence, or inability to stand) in 26% of cases. Treatment was given to 46% of cases, with tylosin being the most commonly used treatment (50% of treated cases). The most common outcome was immediate drying off to be culled without treatment (32%), followed by still milking and recovered but with lasting problems (25%). Nearly half of all the milk samples submitted were culture negative. Streptococcus uberis (14%), non-aureus staphylococci (12%), and Staphylococcus aureus (11%) were the most common isolates, found on 12, 8 and 8 of the 16 farms with microbiological data, respectively.

Conclusions: Clinical mastitis affected up to 6% of ewes at the farm level. Systemic signs were observed in one quarter of affected ewes, suggesting a role for supportive treatment. Clinical mastitis can be severe and challenging to fully resolve in New Zealand dairy sheep.

Clinical relevance: This is the first systematic study of clinical mastitis in New Zealand dairy ewes. It provides baseline information specific to New Zealand conditions for farmers, veterinarians, and other advisors to guide the management of mastitis for the relatively new dairy sheep industry in New Zealand.

Case history: A line of 25 cull cows were all found to have ulcerative lesions of the tongue at post-mortem inspection in a New Zealand slaughter plant. A further 9 of 10 cows inspected at the farm of origin had similar oral lesions. There were no other clinical signs or indicators of ill-health observed at ante-mortem inspection in the abattoir or on the farm. The cows had been fed baleage for 3 weeks prior to slaughter, made from pasture in paddocks heavily contaminated with yellow bristle grass (Setaria pumila).

Clinical findings: There was extensive and deep transverse linear ulceration in the lingual fossa immediately rostral to the torus linguae. At histological examination, full-thickness ulceration of the stratified squamous epithelium was observed with a bed of disorganised collagenous tissue and extensive mixed inflammatory infiltrate extending into the sub-epithelial connective tissue and skeletal muscle. Barbed plant fragments were embedded in both the superficial and deeper areas of inflammation. Detailed examination of the baleage also found that yellow bristle grass seedheads were present.

Diagnosis: Based on the presence of barbed plant material in the tongue and yellow bristle grass seeds in the baleage, a diagnosis of ulcerative stomatitis associated with yellow bristle grass was made.

Clinical relevance: Clinicians should be aware of the potential for hay or baleage contaminated with yellow bristle grass to cause oral lesions in cattle.

Aims: To describe the characteristics of companion animal rescue organisations (CARO) in New Zealand; to describe current capacity, resource limitations and challenges of CARO with a particular focus on cats and dogs; and to explore support for creating a national database of CARO in New Zealand.

Methods: A cross-sectional survey was administered to CARO in New Zealand in May 2022. The survey asked about organisational characteristics, types and numbers of animals cared for, services provided, policies, staffing, funding sources, challenges, and attitudes towards a national database for rescue organisations. Descriptive statistics were provided for all quantitative study variables and free-text comments were analysed for common themes.

Results: The survey was completed by 106/208 (51%) known CARO distributed across the country. These CARO provided services to an estimated 59,874 homeless animals annually with 86/106 (81%) providing services to cats and/or dogs. Primary services provided by CARO who cared for cats or dogs included rehoming (72/86; 84%) and housing (70/86; 81%) animals. Intake was managed through a combination of strategies. Donations (72/86; 82%) were the main funding source. The 62 registered charities were more likely to report being funded by grants than the 23 non-charities (39/62 (63%) vs. 1/23 (4%); p < 0.001), and non-charities were more likely to self-fund (18/23 (78%) vs. 20/62 (32%); p < 0.001). Nearly half of the CARO that provided workforce information (35/72; 49%) had a workforce of 10 or fewer including volunteers. A total of 5,699 people worked for 86 CARO that care for cats or dogs of whom 4,847 (85%) were part-time volunteers. Of the 72 cat and dog CARO who provided workforce information, 57/72 (79%) relied solely on volunteers.The majority of all 106 CARO respondents (78/106; 73%) indicated they were likely to register on a national database of CARO, subject to addressing concerns about time required and information security.CARO respondents described challenges of insufficient funding, access to veterinary services, and a shortage of volunteers and foster homes, with additional concerns including a lack of public awareness, supportive legislation, and resources. Financial support (90/106; 85%) and policy change (76/106; 72%) were preferred support options.

Conclusions: This study highlights the significant role played by CARO in New Zealand and the challenges they face, emphasising the need for financial support, legislation, and initiatives extending beyond the rescue sector to reduce the number of animals being surrendered. The findings also suggest a willingness among CARO to participate in a national database.