New Zealand veterinary journal最新文献

Aims: To describe the morphology and prevalence of teat and udder pathology of New Zealand dairy ewes.

Methods: A repeated cross-sectional study was conducted on 20 commercial New Zealand dairy sheep farms over the 2022-2023 season. Approximately 15 randomly selected ewes were examined on each farm in early, mid, and late lactation. Four udder morphology measures were scored on a 5-point scale: depth (1 = pendulous, 5 = compact udder), suspension (ratio of width at abdominal attachment to height, 1 = low, 5 = high), gland separation (1 = zero, 5 = maximum separation), and teat placement (1 = distally located, vertically oriented, 5 = laterally located, horizontally oriented teats). Teat length and width were measured, and the presence of supernumerary teats, asymmetry, visible teat/udder inflammation, and lesions were recorded. Teats and glands were palpated for consistency, gland-nodules, teat canal thickening, and patency, and teat ends scored for hyperkeratosis. Teat and gland-level pathological variables were converted to ewe-level scores. The presence of involuted, non- or minimally lactating glands was recorded. Data were analysed using descriptive statistics.

Results: Across the three visits, 893 observations were made on 882 unique ewes. Mean teat length and width were 27.5 (95% CI = 27.2-27.7) and 15.8 (95% CI = 15.7-15.9) mm. Udder depth, separation, suspension, and teat placement had modal scores of 4, 3, 3, and 3 respectively, and varied across visits and age groups. Asymmetrical udder prevalence was 39% (95% CI = 35.5-42%) overall and increased with age (27% for 1-year-olds, 38% for two-year-olds, 43% for mixed age ewes). Supernumerary teats were observed in 15% (95% CI = 13-17.9%) of ewes. There was between-farm variation in all udder morphology variables. Ewe-level prevalences of teat end hyperkeratosis (any degree of severity), gland/teat inflammation, lesions, palpable defects, and involuted glands were all < 6%.

Conclusions: Morphological observations resembled those from overseas dairy sheep. Teat dimensions, udder depth, separation, suspension, teat placement, and presence of supernumerary teats varied between farms. Udder depth, separation, and suspension scores decreased with age, while teat placement score and the prevalence of asymmetry increased with age. Teat and udder pathology were rare.

Clinical relevance: This is the first systematic study of teat and udder morphology and pathology in New Zealand dairy ewes. The data will be useful for farmers and industry partners, providing a comparison with their own flocks, identifying areas for improvement, and informing and contrasting with future studies.

Aims: To assess whether herd-level lameness prevalence can be estimated on New Zealand dairy farms, by scoring the first, middle, or last 100 cows in the milking order. In pasture-based herds, whole herd locomotion scoring requires an assessor outside the milking parlour throughout milking. If sufficiently predictive, sampling a proportion of the herd based on milking order, could reduce the costs and time of welfare assessments.

Methods: Six pasture-based, spring-calving, dairy farms in the Manawatū region of New Zealand were conveniently selected. Visits occurred at approximately 6-week intervals between October 2021 and May 2022. Cows were scored using the DairyNZ lameness score (0-3). The assessor tallied cows as they left the parlour and recorded the milking order of those with a lameness score ≥ 2. Data were analysed to determine the association between farm, visit and the proportion of lame cows in the first, middle, and last 100 cows, and the agreement between the prevalence of lame cows in those groups and from whole herd scoring.

Results: Across all visits, 263 lame cows were recorded. Of these, 40.7% were in the last 100, 25.9% in the middle 100, and 14.4% in the first 100. Farm, visit and their interactions with group were all statistically significant (p < 0.001). While, overall, the last 100 cows had the highest proportion of lame cows, this pattern varied across farms and visits, Limits-of-agreement plots showed that as herd prevalence increased, agreement between the prevalence in each sample group and herd prevalence worsened. When herd prevalence exceeded 5%, only the middle 100 sampling group had a limits-of-agreement < 5%.

Conclusions: Variations across farms and seasons in the proportion of lame cows in each part of the milking order lead to variations in the accuracy of predicting overall lameness from such samples. Based on limits-of-agreement, observing the middle 100 cows is likely to be the most accurate sample, but is still likely to be of limited value on New Zealand dairy farms, especially as a single, one-off measurement.

Clinical relevance: On New Zealand dairy farms, locomotion scoring the middle 100 cows in the milking order as part of a welfare assessment would reduce costs and time but would not produce an accurate estimate of whole-herd lameness prevalence. However, it may be useful as a screening tool in herds routinely locomotion scoring throughout the year.

Case history: This report details investigations into nine cases of neurological disease and/or sudden death in 8-13-week-old puppies between 2021 and 2024. Aside from two pairs of littermates, cases were unrelated. The puppies had an onset of clinical signs 9-23 days following at least one "on-label" dose of a commercially available quadrivalent vaccine containing live attenuated canine distemper virus (CDV).

Clinical findings: Eight of the nine cases displayed signs typical of "classic distemper," including seizures, circling, tremors, hypersalivation, progressive neurological deficits, pyrexia, and/or respiratory and gastrointestinal signs. Pathological and molecular investigations were undertaken in eight cases. Mononuclear/lymphohistiocytic encephalitis or meningoencephalitis with or without neuronal intranuclear inclusion bodies was present in seven cases. Five cases had bronchopneumonia. Other lesions included poliomyelitis, necrotising enteritis and myocardial necrosis or myocarditis. PCR for CDV was positive on tissues from seven cases, and immunohistochemistry for CDV was positive on neural tissues in six cases. Whole genome sequencing of PCR amplicons demonstrated a Rockborn-like strain with 99.9% homogeneity between samples from four cases and a vial of vaccine.

Diagnosis: Based on the combination of case history, pathological findings, molecular test results and/or whole genome sequencing, a diagnosis of post-vaccinal canine distemper was confirmed in six cases and presumed in two.

Clinical relevance: Outbreaks of canine distemper have been stemmed by widespread vaccination starting in the mid-twentieth century. Consequently, confirmed cases of natural CDV have not been reported in New Zealand since an outbreak in the 1980s, and CDV is considered a "notifiable organism" as per the Biosecurity Act 1993. This is the first case series to report genomic investigation of post-vaccinal canine distemper in New Zealand puppies and highlights a rare adverse event associated with routine vaccination. Our results suggest that puppies with neurological, respiratory and/or gastrointestinal disease with an onset within 6 weeks of vaccination with live attenuated CDV should be reported and investigated accordingly.

Aims: To describe the current capacity, resource limitations and challenges of cat and kitten rescue organisations (CKR) in New Zealand; to document the source and destination of the animals cared for; and to explore the role of foster programmes in cat rescue and rehoming in New Zealand.

Methods: A national cross-sectional survey was administered to companion animal rescue organisations in New Zealand in May 2022. For those engaged in CKR, the survey included questions about types and numbers of cats cared for, facilities, locations, origins and outcomes of cats in care, reasons for owner surrender, whether the CKR had a foster programme, and foster programme capacity. Descriptive statistics were provided for all quantitative study variables and free-text comments were analysed for common themes.

Results: Of the 64 organisations that indicated they cared for cats on the broader companion animal rescue survey, 50 (78%) completed the questions on CKR. At the time of the survey, these 50 organisations cared for an estimated total of 6,206 cats (median 39 (IQR 17-96) cats per CKR). The highest reported source of animals was strays (median of the CKR's reported percentage: 72%; IQR 50-93%), followed by surrendered animals (median 14.5%; IQR 5-31%). The most common reasons for owners surrendering animals were unplanned litters, lack of pet-friendly accommodation, and inability to afford to care for the animal's daily needs. An estimated median of 66% (IQR 60-80%) of cats under care in the previous year were subsequently rehomed. Most CKR were "usually" (26/50; 52%) or "always" (11/50; 22%) full to capacity. The majority of CKR that responded operated a fostering programme (40/50; 80%), with an estimated 59% (3,619/6,206) of all cats currently in the care of CKR located in foster homes. The availability of fosterers was identified by CKR as the most important factor affecting their ability to accept animals.

Conclusions and clinical relevance: These findings highlight that CKR in New Zealand currently handle a large volume of animals each year. Initiatives that focus on preventing unplanned litters, ensuring owned free-roaming cats have permanent identification through microchipping, and initiatives to prevent unnecessary owner relinquishment may help to reduce the number of animals entering care. With the majority of CKR relying on foster programmes, there is a need for further research to better understand how these operate and whether there may be opportunities to expand their capacity.

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.

Case history: Medical records of cases with pleural effusion managed with the PleuralPort device (PPD) were reviewed retrospectively at two veterinary hospitals in Italy. Cases with PPD placement at initial or second surgery and with a minimum follow-up of 4 weeks were included. Data retrieved from the records included signalment, fluid analysis, duration of implantation, duration of function, and complications. The PPD was placed subcutaneously in the dorsal thorax and connected to a drainage tube inserted in the pleural space. Complications were divided into intra-operative, short-term (≤ 12 weeks) and long-term (> 12 weeks). Owners were contacted by telephone for follow-up information, using a non-standardised questionnaire.

Clinical findings: A total of 30 animals were included in the study: 26 dogs and four cats. Pleural fluid was compatible with chylothorax (22/30), neoplastic pleural effusion (5/30) and inflammatory pleural effusion (3/30).No intra-operative complications were reported. Overall, post-operative complications occurred in 9/30 (30%) patients. Major complications developed in six (20%) cases, including infection, tube kinking, pneumothorax and obstruction. Minor complications in four cases (13.3%) included skin inflammation, discomfort and dislocation of the device. Short-term complications developed in 7/30 (23.3%) cases and long-term complications in 3/22 (13.6%) cases that survived longer than 12 weeks after surgery. Owner satisfaction was very good in 28/30 (93.3%) cases.

Conclusions and clinical relevance: The PPD was well tolerated by the animals and was a feasible alternative to thoracostomy tubes for the management of chronic pleural effusion in dogs and cats. Although complications were relatively common, they were easily treated in most patients.