Donkeys have contributed to the development and livelihoods of humans for almost 7,000 years. They have been used for traction and transportation, kept as pets, utilized in animal-assisted therapies, or farmed as food-producing animals. Over the past two decades, significant progress has been made in bridging the knowledge gap in veterinary medicine between donkeys and horses. Veterinary practitioners are now more aware that donkeys have important behavioral, anatomical, and physiological characteristics that distinguish them from horses. These peculiarities should be considered when treating donkeys. For instance, donkeys are highly efficient in compartmentalizing and conserving water and metabolizing xenobiotics via cytochrome P450 enzymes. This affects the selection of drugs and their dosages. Estimating live weight and recognising and assessing pain accurately are also important factors when instituting pharmacological treatments for donkeys. Therapeutic regimens have been established for some drugs in donkeys, but many are still directly extrapolated from horses. Because donkeys are classified as a minor species, there are relatively few medications approved for their use. In addition, some cultures also consider donkeys as to have lower economic value than horses, which may preclude donkeys from receiving appropriate veterinary care. Veterinary education on donkey-specific topics would improve the health and ultimately the welfare of these animals. This review explores the characteristics of donkeys and offers guidance on their care and treatment, aiming to enhance their overall quality of life.

Case historyIn mid-summer (February), 42 of a flock of 68 ram hoggets (approximately 5 months of age) and two of a group of 14 alpacas on a farm in the Manawatu region of New Zealand were found recumbent or dead following a period of persistent rain, strong winds and relatively low temperatures. The hoggets and alpacas had been shorn 4 and 53 days previously, respectively, and were in adequate to good body condition with access to ad libitum pasture. Post-mortem and histological examinations were undertaken on four hoggets and two alpacas.Clinical findingsApart from hypothermic body temperatures from four recumbent hoggets, nothing of significance was identified on clinical or gross pathological examination. Histological changes of vacuolar hepatopathy, renal tubular degeneration and pulmonary congestion were present in all animals examined.DiagnosisBased on the history and clinical and pathological findings, hypothermia was highly probable to have been the cause of the deaths.Clinical relevanceThese cases emphasise the importance of shelter for recently shorn sheep and alpacas regardless of the season.

AIMS:To examine and assess causes of mortality of kiwi (Apteryx spp.) submitted to Massey University between 2010 and 2020 across the five recognised species according to location, age group and captivity status in New Zealand. METHODS:Post-mortem reports were obtained from the Massey University/Te Kunenga ki Pūrehuroa School of Veterinary Science/Wildbase Pathology Register. Inclusion criteria were all species of kiwi with a date of post-mortem examination between August 2010 and August 2020. Data from each report was exported, categorised and compared using Microsoft Excel. RESULTS:Of a total of 1,005 post-mortem reports, there were 766 North Island brown kiwi (NIBK; A. mantelli), 83 tokoeka (A. australis), 73 rowi (A. rowi), 49 great spotted kiwi (A. haastii), and 34 little spotted kiwi (A. owenii). This comprised 19 eggs/embryos, 125 neonatal, 473 juvenile, 153 subadult, and 235 adult kiwi. There were 615 kiwi from wild populations, 148 from sanctuary populations, 238 from captivity, and four from unspecified locations. The leading cause of death was trauma, affecting 322 (32.0 (95% CI = 29.2-35.0)%) kiwi including 289 (37.3 (95% CI = 26.0-31.7)%) NIBK. Nearly half of these died from predation by mustelids, with losses recorded from neonates to adults and clustered in the central to southern North Island. Predation by dogs was the second most common cause of death, killing 84 (8.4 (95% CI = 6.7-10.2)%) kiwi, of which 65.5% came from the northern districts of the North Island. Non-infectious disease killed 214 (21 (95% CI = 18.8-24.0)%) kiwi, and included developmental deformities, gastrointestinal foreign bodies and predator trap injuries. Infectious disease killed 181 (18.0 (95% CI = 15.7-20.5)%) kiwi and the proportion decreased with age, with common diagnoses including coccidiosis, bacterial septicaemia, avian malaria, and fungal respiratory disease. Starvation affected 42 (4.2 (95% CI = 3.0-5.6)%) kiwi, comprised of mainly neonatal or juvenile individuals from wild or sanctuary populations, with a higher percentage seen in tokoeka (11/83; 13.3%) compared to other species (min 0%, max 5.9%). The cause of death was undetermined in 246 (24.5 (95% CI = 21.8-27.3)%) cases, which was most often due to poor preservation of remains. This included 33/73 (46%) rowi and 32/83 (39%) tokoeka, and affected mainly birds from sanctuary and wild populations. CONCLUSIONS:This study enhances our understanding of causes of mortality in captive, wild and sanctuary populations of all kiwi species and age groups within contemporary New Zealand.

Case histories: Medical records of four dogs diagnosed with protothecosis in New Zealand were reviewed. The dogs were aged between 4 and 9 years and three of the four dogs were female. Breeds were one Labrador, one Miniature Schnauzer and two crossbreeds. The reasons for initial veterinary evaluation were a cough and opaque appearance of the right eye (Case 1), diarrhoea (Cases 2 and 3), and cutaneous disease (Case 4).Clinical findings: The ocular signs were characterised by panuveitis, retinal detachment and secondary glaucoma. Gastrointestinal signs included chronic haemorrhagic diarrhoea due to colitis. Three cases had disseminated infection and developed both bilateral, blinding, ocular disease and chronic gastrointestinal disease. Cutaneous signs consisted of draining fistulae over the olecranon, multifocal cutaneous nodules, and ulceration and tracts of the foot pads. Disseminated protothecosis was confirmed by histopathology of biopsied ocular tissues in Cases 1 and 2 and by gastrointestinal biopsies in Case 3. Prototheca spp. were also identified in cytological specimens from Cases 1 and 4 and recovered by culture in Cases 2 and 4. Cutaneous protothecosis was diagnosed in Case 4 initially by cytology and histopathology of skin lesions, and Prototheca zopfii was confirmed by PCR of cultured organisms.Treatment and outcome: Prior to diagnosis of protothecosis, a variety of treatments were prescribed to treat the gastrointestinal and ocular signs. After diagnosis, only Cases 2 and 4 received medication aimed at treating the protothecal infection, which was itraconazole in both cases. Following the progression of clinical signs and concerns about quality of life, all four dogs were euthanised.Diagnosis: Disseminated protothecosis in three dogs, cutaneous protothecosis in one dog.Clinical relevance: Canine protothecosis is rarely reported, despite the ubiquity of the causal algae, and the disease usually carries an extremely grave prognosis when infection is generalised. In New Zealand, protothecosis should be considered as a differential diagnosis in dogs with panuveitis, chorioretinitis or retinal detachment, colitis, or nodular, ulcerative or fistulating cutaneous lesions.

Avian malaria caused by Plasmodium species is a known cause of mortality in avifauna worldwide, however reports within New Zealand kiwi (Apteryx spp.) are scant. Postmortem reports from kiwi were obtained from the Massey University/Te Kunenga ki Pūrehuroa School of Veterinary Science Pathology Register from August 2010–August 2020. Gross lesions were described from postmortem reports, and archived H.E.-stained slides used for histological assessment. Nested PCR testing was performed on formalin-fixed paraffin-embedded tissue samples to assess the presence of Plasmodium spp. and Toxoplasma gondii DNA and cases with a PCR-positive result were sequenced to determine the lineage involved. Of 1005 postmortem reports, 23 cases of confirmed or suspected avian malaria were included in this study. The most consistent gross lesions included splenomegaly, hepatomegaly, and interstitial pneumonia with oedema. Histological lesions were characterised by severe interstitial pneumonia, pulmonary oedema, interstitial myocarditis, hepatic sinusoidal congestion and hypercellularity, and splenic macrophage hyperplasia and hyperaemia/congestion with numerous haemosiderophages. Cytoplasmic meronts were consistently found within endothelial cells of a variety of tissues, and within tissue macrophages of the liver, lung and spleen. A diagnosis of avian malaria was confirmed via PCR testing in 13 cases, with sequencing revealing P. matutinum (LINN1) and P. elongatum (GRW6) as the species involved. This is the largest case series describing the pathology of avian malaria as a cause of mortality in endemic New Zealand avifauna.

There is a large population of donkeys in Saint Kitts; however, hematological and biochemical reference intervals (RIs) are lacking. This study addressed this deficiency by following the American Society for Veterinary Clinical Pathology RI guidelines. Sixty-six healthy, gelding standard donkeys with a median and interquartile range age of 5 years (3.5 - 8 years) and a mean ± standard deviation body weighed of 156 ± 16.7 kg were used to produce a five-part differential complete blood count using an impedance-based analyzer. Clinical chemistry analytes were quantified using a photometric-based analyzer utilizing two reagent rotors that determined 14 and 11 analytes, respectively. An electrochemical-based analyzer quantified chloride, sodium and potassium. Reference intervals were computed using Reference Value Advisor. Results of analytes determined using different rotors/analyzers were assessed using Passing-Bablok regression and Bland-Altman plot analyses. Reference intervals for 43 hematological and biochemical analytes were generated. Reference intervals for hematocrit, red blood cells, white blood cells, total protein, glucose, blood urea nitrogen, and creatinine were 23.67% - 38.08%, 4.08 - 6.42 1012/L, 4.7 - 12.34 109/L, 5.84 - 6.93 g/dL, 64.7 - 130.9 mg/dL, 11.1 - 13.4 mg/dL, and 0.67 - 1.36 mg/dL, respectively. There was good agreement between detection system for albumin, aspartate aminotransferase, gamma glutamyl transferase, total protein, globulin, and potassium, but not for blood urea nitrogen, calcium, creatinine kinase, and sodium. This study is the first to establish hematological and biochemical RIs in donkeys in Saint Kitts. These values will be useful for clinical decision-making.

Five of 95 rats in an oral safety study developed uroliths, with two of these rats also developing pyelonephritis. Histology of the urinary tract revealed squamous metaplasia suggestive of vitamin A deficiency. Analysis of the diet showed around half the expected concentration of vitamin A, although the concentrations were close to the published nutritional requirements for rats. Due to the presence of squamous metaplasia of the transitional epithelium and the low vitamin A concentration in the diet, a presumptive diagnosis of vitamin A deficiency was made, although an interaction between the low vitamin A concentrations and other dietary components appears possible. Although the uroliths did not cause clinical signs of disease, the lesions observed during this study could have been misinterpreted as being due to the test substance. Observations from this study highlight the need for high-quality food to ensure background lesions do not develop when performing safety studies in rats.

Inter-pathologist variation is widely recognized across human and veterinary pathology and is often compounded by missing animal or clinical information on pathology submission forms. Variation in pathologist threshold levels of resident inflammatory cells in the tissue of interest can further decrease inter-pathologist agreement. This study applied a predictive modeling tool to bladder histology slides that were assessed by four pathologists: first without animal and clinical information, then with this information, and finally using the predictive tool. All three assessments were performed twice, using digital whole-slide images (WSI) and then glass slides. Results showed marked variation in pathologists’ interpretation of bladder slides, with kappa agreement values of 7–37% without any animal or clinical information, 23–37% with animal signalment and history, and 31–42% when our predictive tool was applied, for digital WSI and glass slides. The concurrence of test pathologists to the reference diagnosis was 60% overall. This study provides a starting point for the use of predictive modeling in standardizing pathologist agreement in veterinary pathology. It also highlights the importance of high-quality whole-slide imaging to limit the effect of digitization on inter-pathologist agreement and the benefit of continued standardization of tissue assessment in veterinary pathology.

This pilot study aimed to assess the welfare impacts of different causes of pre-weaning deaths in piglets. Piglets that died between 0–7 days after birth (n = 106) were collected from two commercial pig farms and subject to post-mortem examination to confirm their cause of death as well as any contributing factors. Using the Five Domains Model, the most likely affective experiences associated with the pathological findings were carefully inferred to better understand affective experience as it related to known causes of liveborn piglet mortality. The most common causes of liveborn piglet mortality were starvation (23%), crushing (23%) and non-viable (21%). Thirty one piglets had evidence of starvation, but it was only considered the primary cause of death in 15 piglets, as cofactors such as poor viability (n = 13) were also present in many piglets with evidence of starvation. All 15 piglets that were crushed died within 24 h after birth and most had evidence of thoracic and/or abdominal internal bleeding. This study found that common causes of liveborn piglet death were associated with compromises in Domains 1 (Nutrition/hydration), 3 (Health/function), and4 (Behavioural interactions), with the most likely resulting affective states described in Domain 5 (Mental state). This highlights the interaction between physical/functional and situation-related (behavioural) aspects that influence an animals’ welfare status.

Foot-and-mouth disease virus (FMDV) is widespread throughout much of the world, including parts of South East Asia. Surveillance is often limited in endemic areas, relying predominantly on passive outbreak reporting. As part of the World Organisation for Animal Health (OIE)'s South East Asia and China Foot-and-Mouth Disease Project (SEACFMD), field sampling was performed to help understand evidence of widespread virus exposure observed in previous studies. Serum and dry mucosal swabs were collected to evaluate the presence of FMDV RNA on the nasal, oral, and dorsal nasopharyngeal mucosal surfaces of 262 healthy cattle (n = 84 in Laos; n = 125 in Myanmar) and buffalo (n = 48 in Laos; n = 5 in Myanmar) immediately following slaughter in three slaughterhouses. Swabs and serum were tested by the OIE/FAO World Reference Laboratory for foot-and-mouth disease (WRLFMD) using pan-serotypic real-time reverse transcription-PCR (rRT-PCR) and serum was evaluated using the FMD PrioCHECK non-structural protein (NSP) ELISA. In total, 7.3% of animals had detectable FMDV RNA in one or more of the three sites including 5.3% of nasopharyngeal swabs, 2.3% of oral swabs, and 1.5% of nasal swabs. No FMDV RNA was detected in serum. Overall, 37.8% of animals were positive for NSP antibodies, indicating likely past natural exposure to FMDV. Results were comparable for Laos and Myanmar, and for both cattle and buffalo, and were not significantly different between age groups. Detectable FMDV RNA present on the oral and nasal mucosa of clinically-healthy large ruminants in Laos and Myanmar demonstrates the importance of sampling asymptomatic animals as part of surveillance, and may indicate that subclinical infection plays a role in the epidemiology of FMD in these countries.

Reports of congenital oral tumours in New Zealand cattle are extremely rare. In a review of 372 bovine neoplasms referred to Ruakura Veterinary Diagnostic Station from 1955 to 1968 only one congenital oral tumour was described (Shortridge and Cordes 1971). This was a mastocytoma of the tongue, reported as an incidental finding in a 2-week-old calf (Dodd 1964). Worldwide, reports of congenital oral tumours are equally sporadic. A literature search in Web of Science, on 3 June 2020 using the search terms “congenital AND gingiva OR mouth OR oral OR tongue AND tumour OR growth OR hamartoma AND calf OR calves” retrieved only seven peer-reviewed papers. However, when reported, the majority of these tumours tended to be vascular in origin, and were often diagnosed as vascular hamartomas, with a predilection for the rostral mandibular gingiva (Nourani et al. 2007; Doğan et al. 2013; Hashida et al. 2017). Haemangiosarcomas have also been reported, but are much rarer (Azizi et al., 2017). This case study describes the occurrence of a congenital gingival vascular hamartoma in a calf, and to the authors’ knowledge is the first report of this type of tumour in a calf in New Zealand. A female Jersey x Holstein Friesian calf, weighing approximately 50 kg, born 22 July 2019, from a 900cow commercial dairy farm in the Waikato region, was presented for veterinary examination 4 days later. At 3 days of age, the calf was observed having difficulty suckling and a gingival mass was noted by farm staff. Gross examination of the oral cavity revealed a 3 × 1.5 cm, dark pink, lobulated mass located on the left rostral side of both the buccal and lingual aspects of the mandibular gingiva (Figure 1a). Three incisor teeth were affected, with the second incisor being markedly displaced cranio-medially. Although there was no ulceration present, the mass was friable and minimal trauma resulted in copious bleeding. The calf was sedated with 0.4 mg/kg xylazine I/M (Phoenix Xylazine 2% Injection; Phoenix Pharm Distributors Ltd, Auckland, NZ) and the gingiva desensitised by local infiltration of 0.6 mg/kg lignocaine (EALopaine 2%; Ethical Agents Veterinary Marketing Ltd, Auckland, NZ). A single circumferential nylon (Supramid USP 3 + 4; Serag-Wiessner KG, Naila, Germany) ligature was placed around the base of the mass. Sedation was reversed using I/V 0.3 mg/kg tolazoline (Akorn Tolazine Injection; Caledonian Holdings Ltd, Auckland, NZ) and postoperative analgesia provided with S/C 0.5 mg/kg meloxicam (Metacam 20 mg/mL for Injection; Boehringer Ingelheim Animal Health NZ, Auckland, NZ). After the placement of the ligature, the calf recovered the ability to suckle and appeared to grow at a similar rate to its peers, as assessed visually. However, when the calf was re-visited 2 weeks later, the mass was still present, and the ligature had loosened. The calf was again sedated with xylazine and local infiltration performed as before and an attempt was made to remove the mass using portable cryotherapy (Histofreezer; OraSure Technologies Inc, Bethlehem, PA, USA), combined with surgical resection. Unfortunately, the cryotherapy proved ineffective for haemostasis and the surgery was curtailed. Instead, a decision was made to pursue the intensive use of nylon ligatures, using two ligatures instead of one, in order to decrease vascularity and size of the mass. As described previously, sedation was reversed with tolazoline, and meloxicam was given for analgesia. The two ligatures were regularly replaced every 5–7 days by a veterinarian, using the method described, to ensure that they remained tight enough to restrict blood supply. After 1 month of treatment, when the calf was 7 weeks old, it was considered that the mass had decreased sufficiently in size to attempt surgery again. Although smaller, the mass was still highly vascular and was now associated with severe lip distortion. The calf was again sedated with xylazine as described above, and a left mental nerve block performed using 0.3 mg/kg 2% lignocaine. The bulk of the tissue mass was resected using a number 22 scalpel blade and a portable thermocautery unit (Statham Instruments Inc., Oxnard, CA, USA), which provided excellent haemostasis. Sedation was reversed using tolazine, as above. Post-operatively the calf was given a single I/M dose of 2.5 mg/kg flunixin (Flunixin Injection; Norbrook NZ Ltd, Canterbury, NZ) and 24,000 IU/kg long-acting penicillin (Intracillin LA; Virbac, Hamilton, NZ) was also administered I/M which was repeated 3 days later. In addition, the calf was given I/M 3.75 mg/kg ketoprofen (KetoMax 15%; Agrihealth NZ Ltd, Auckland, NZ), daily for 4 days, commencing 24 hours after the surgery. The calf made a full recovery and no significant postoperative bleeding was observed. Over the

Foot-and-mouth disease virus (FMDV) is widespread throughout much of the world, including parts of South East Asia. As part of the World Organisation for Animal Health (OIE)’s South East Asia and China Foot‐and‐Mouth Disease Project (SEACFMD), field sampling was performed to help understand evidence of widespread virus exposure observed previously. Serum and dry mucosal swabs were collected to evaluate the presence of FMDV RNA on the nasal, oral, and dorsal nasopharyngeal mucosal surfaces of 262 healthy cattle (n=38 in Laos; n=47 in Myanmar) and buffalo (n=12 in Laos; n=2 in Myanmar) immediately following slaughter in three slaughterhouses. Swabs and serum were tested by the OIE FMD world reference laboratory using pan‐serotypic real‐time reverse transcription‐PCR (RT‐PCR) and serum was evaluated using the FMD PrioCHECK non-structural protein (NSP) ELISA. In total, 7.3% of animals had detectable FMDV RNA in one or more of the three sites including 5.3% of nasopharyngeal swabs, 2.3% of oral swabs, and 1.5% of nasal swabs. In all animals, serum was found not to contain detectable FMDV RNA, and 37.8% of animals were positive for NSP antibodies, indicating likely past exposure to FMDV. Results were comparable for Laos and Myanmar, and were similar for both cattle and buffalo. The current study demonstrates the utility of detection by swabbing the nasopharynx in the post-mortem context, in situations such as post-mortem where probang samples are not feasible. Additionally, FMDV present on the oral and nasal mucosa of clinically-healthy large ruminants in Laos and Myanmar, if viable, may potentially play a role in the epidemiology of FMD in these countries, and perhaps more widely within Southeast Asia.

Aims:To compare detection by real-time PCR of DNA fromMycoplasma bovison mucosal swabs taken from the palatine tonsillar crypt and the mainstem bronchi of clinically asymptomatic calves after slaughter. Methods:We compared the sensitivity of mucosal swabs taken from two sites: the palatine tonsillar crypt and the mainstem bronchi. Paired samples were taken post-mortem at slaughter from 55 clinically well calves from an infected herd and were tested by real-time PCR for the presence ofM. bovis-specific DNA. Results:Mycoplasma bovisDNA was detected in 51 palatine tonsillar crypt swabs (92.7 (95% CI = 82.4-98.0)%) and seven mainstem bronchial swabs (12.7 (95% CI = 5.3-24.5)%). All seven calves with positive mainstem bronchial swabs also had positive palatine tonsillar crypt swabs. Conclusions:When compared to mucosal swabs of the mainstem bronchi, mucosal swabs of the palatine tonsillar crypt were seven times more sensitive for the post-mortem detection ofM. bovisDNA. The viability of detectedM. boviswas not assessed, because any cattle carrying viable or non-viableM. bovisDNA were determined to be a potential risk to eradication. Palatine tonsillar crypt mucosa may be a useful anatomical site for real-time PCR detection ofM. bovisDNA in naturally infected calves. More work is needed to define the persistence and viability ofM. bovisat this anatomical site.

In 2013 there was an outbreak of crusting ventral dermatitis among a group of juvenile rowi (Apteryx rowi), a species of the endangered New Zealand kiwi, that were being raised on an off-shore island sanctuary. Biopsies taken at the time found nematodes migrating within the epidermis of affected skin but the specific identity and origin of the organisms was not established, and sporadic cases of similar skin disease continue to occur on the island. On examination of additional sections from the original skin biopsies, adult nematodes and eggs were identified, the histomorphology of which was consistent with Capillaria sensu lato. PCR was performed on DNA extracted from archived formalin-fixed, paraffin-embedded tissue blocks of skin from eight affected rowi, using primers targeting the 18S region of nuclear ribosomal DNA and the COI gene of mitochondrial DNA of capillarid nematodes. The 18S sequences from all rowi samples were identical and matched sequences from members of the genus Eucoleus. In contrast, two distinct capillarid COI sequences were obtained, in one case both from the same rowi skin biopsy. While there were no close matches, both COI sequences also aligned nearest to sequences identified as Eucoleus spp. It is considered unlikely that two different nematode species are involved in the rowi skin lesions and the possible amplification of a COI pseudogene or “numt” is discussed. A species-level identification of the capillarid nematodes causing skin disease in rowi was not obtained, however based on histological evaluation the infections include reproductively-active adult nematodes. This finding indicates the possibility of perpetuation of the skin disease in the absence of the original source, as well as raising potential for the transfer of infection from the island when the juvenile rowi are translocated to their new habitats.

Sporadic cases of visceral and neural nematode larva migrans have been diagnosed at necropsy in the endangered New Zealand kiwi (Apteryx spp.), but the causative organisms have not yet been definitively identified. From an initial group of five affected kiwi, PCR was performed on DNA extracted from archival formalin-fixed paraffin-embedded tissue sections in which larval nematodes had been histologically identified. Sequencing of positive results from four out of the five kiwi aligned with sequences from Toxocara cati, a nematode parasite whose definitive host is the domestic cat. PCR was then performed on a second group of 12 kiwi that had histologic inflammatory lesions consistent with larva migrans, but variable larval presence. Repeatable positive PCR results were only achieved in one tissue, in which larval organisms were histologically confirmed. This study supports the use of PCR as an alternative or adjunct to the morphological identification of nematode larvae in formalin-fixed histopathological samples, as well as showing that in investigation of larva migrans, PCR has greatest chance of success from sections where nematode larvae are evident histologically. The identification of Toxocara cati from lesions of larva migrans in kiwi reflects an indirect, parasite-mediated effect of an invasive mammalian species on a native species.

Case History: A group of 39, 19-22-month-old Friesian bulls were administered an ivermectin/closantel anthelmintic via intended S/C injection in the ischiorectal fossa on 15 June 2017 (Day 0). Over the next 50 days, 22 affected bulls presented various degrees of anorexia, abdominal pain and urine dribbling. Seventeen bulls were examined by transrectal ultrasonography which revealed urinary bladder distension in all 17, and peritoneal fluid accumulation in some. Overall, eight bulls died or were subjected to euthanasia. On-farm postmortem examination of three bulls revealed urinary bladder rupture. Clinical Findings: On Day 50 one affected live bull was admitted to Massey University for further investigation. This bull continuously dribbled urine and had an overtly distended urinary bladder as determined by rectal palpation and ultrasonography. Pathological Findings: Postmortem examination of this bull revealed a markedly distended urinary bladder, massive subcapsular and pericapsular renal oedema with retroperitoneal fluid accumulation, minimal hydronephrosis and no evidence of mechanical urinary outflow obstruction. The right ischiorectal fossa contained multifocal areas of tissue fibrosis that extended into areas innervated by the distal cutaneous branch of the pudendal nerve and the pelvic nerve. Histopathological changes consisted of extensive fibrosis, myonecrosis and neurodegeneration, and evidence of granulation tissue and inflammation at the putative injection site and in surrounding tissues. Diagnosis: A local inflammatory reaction at the presumed injection site together with localised peripheral neurodegeneration and myelopathy may have led to detrusor-sphincter dyssynergia causing urine retention.

Background: The ACTH stimulation has low sensitivity for the diagnosis of hypercortisolism possibly as a result of biological and analytical variability.Hypothesis/Objectives: To report the components of biological and analytical variability in serum cortisol concentration post-ACTH stimulation ([cortisol]) in healthy dogs.Animals: Fourteen healthy harrier hound dogs.Methods: The data were extracted from a separate, prospective, randomized, double-blinded, controlled discovery study in which dogs treated with vehicle control and 4 different doses of cortisone acetate (CA) for 7 days had an ACTH stimulation test performed to confirm the dose-dependent effect of CA. The index of individuality (IoI), the critical difference between sequential measurements (CD), and the number of measurements required to assess the homeostatic set point (HSP) of [cortisol] with confidence intervals (CI) of 90 and 95% were estimated.Results: The IoI was equal to 1.1 and the CD was 3.3 mu g/dL (92 nmol/L). The number of measurements required to assess the HSP of [cortisol] with CI of 90 and 95% were 3 and 15, respectively. Additionally, mean [cortisol] was higher in males than in females (13.3 +/- 4 mu g/dL [366 +/- 114 nmol/L] vs. 11.5 +/- 2.5 mu g/dL [318 +/- 65 nmol/L], respectively; P =.046). As expected, treatment with CA resulted in a dose-dependent suppression of [cortisol].Conclusions and Clinical Importance: False-negative test results in hypercortisolism could occur when [cortisol] is outside of the individual's HSP and within the reference interval. The large CD emphasizes the importance of assessing clinically relevant parameters in the diagnosis and monitoring of HC.

Objective To assess and compare the sedative and antinociceptive effects of four dosages of dexme-detomidine in donkeys. Study design Randomized, controlled, crossover, Latin-square, blinded study. Animals Six healthy, castrated, adult, standard donkeys. Methods Dexmedetomidine (2, 3, 4 and 5 mu g kg(-1); D2, D3, D4 and D5), acepromazine (0.1 mg kg(-1)) and saline were administered intravenously to each donkey and a 1 week interval was allowed between successive trials on each animal. Sedation scores (SS) and head heights above ground (HHAG) were used to assess sedation and mechanical nociceptive threshold (MNT) testing to assess antinociception over 120 minutes post-treatment. Areas under the curve (AUC) for 0-30, 30-60 and 60-120 minutes were computed to compare the effect of treatments. Results SS-AUC(0-30) values were larger for D4 and D5, and SS-AUC(30-60) values were larger for D5 than for saline. All dexmedetomidine treatments produced lower HHAG-AUC(0-30) and HHAG-AUC(30-60) values, and acepromazine produced lower HHAG AUC(60-120) values than did saline. For MNT, D3, D4 and D5 increased AUC(0-30) and AUC(30-60) values compared with saline and also AUC(0-30) values compared with D2 and acepromazine. Smaller MNT-AUC(30-60) values were obtained with D2 than with D4 and D5, with D3 than with D5, and with acepromazine than with D4 and D5. Conclusions and clinical relevance Dexmedetomidine induced sedation and dosage-dependent mechanical antinociception. Larger dexmedetomidine dose rates were required to induce antinociception than sedation. Furthermore, the antinociception induced by dexmedetomidine was of shorter duration than its sedation. For minor painful procedures on standing donkeys, D5 may be clinically useful to provide sedation and analgesia.

Although romifidine is commonly used to provide sedation and analgesia for the facilitation of clinical procedures in donkeys, limited scientific information is available for this drug in this species. This randomized, controlled, crossover, Latin-square, blinded study compared the sedative and antinociceptive effects of four dosages of romifidine (40, 60, 80, and 100 μg/kg IV; R40, R60, R80, and R100, respectively), acepromazine (0.1 mg/kg IV; ACE) and saline (0.9%, 5 mL IV) by assigning sedation scores (SS) and measuring head heights above ground (HHAG) and mechanical nociceptive thresholds (MNT) in donkeys. Areas under the curve (AUC) from 0 to 30, 30–60, 60–120, and 120–180 min after administration were computed for SS, HHAG, and MNT and compared among treatments. Romifidine and ACE, but not saline, induced clinical signs of sedation. SS-AUC0–30 for R60, R80 and R100, and SS-AUC30–60 for R100 were higher than corresponding values for saline. HHAG-AUC30–60 for R40 and R80, and HHAG-AUC60–120 for R40, R60, R80 and R100 were smaller than for saline. HHAG-AUC60–120 for R100 were also smaller than those for ACE. Romifidine, but not saline or ACE, increased MNT. MNT-AUC0–30 and MNT-AUC30–60 for R40, R60, R80 and R100, and MNT-AUC60–120 for R80 and R100 were higher than corresponding values for saline and ACE. MNT-AUC60–120 for R100 were higher than for all other romifidine treatments. In donkeys, the degree of sedation was similar for the four dosages of romifidine, but antinociception was dose-dependent.

Pheochromocytoma, a rarely reported adrenal gland neoplasm in Old World primates, was diagnosed in 5 rhesus macaques (Macaca mulatta) and 2 African green monkeys (Chlorocebus aethiops) from 3 research institutions. Age and sex were available for 6 primates. Two males and 4 females were affected, ranging in age from 9 to 31 years. All neoplasms were unilateral and, in the cases reporting the affected gland, 4 involved the right adrenal gland and 2 involved the left. Diagnosis was established by characteristic histologic features. Immunohistochemically, neoplastic cells in all cases expressed chromogranin A and met-enkephalin and were negative for melan-A and inhibin. Six of 7 tumors were positive for β-endorphin. Pulmonary metastases were present in 2 rhesus macaques and portal vein invasion in 1 African green monkey. To the authors’ knowledge, this is the first report of malignant pheochromocytoma in Old World primates.