Hydroureteronephrosis and fetal mummification secondary to uterine torsion in a Merino ewe

A 6 year old pluriparous Merino ewe was presented for investigation of a large intra-abdominal mass. Post-mortem examination revealed a 360° clockwise uterine torsion was present with a mummifying fetus. The torsion involved the left ureter resulting in a severe hydroureteronephrosis. Uterine torsion is uncommon in the ewe, occurring in less than 0.1% of pregnancies in one report (Mahmoud et al. Livest Res Rural Dev 2018;30), but cases are likely to be undiagnosed, particularly under the extensive management conditions typical of Australia. The chronicity of the condition in this ewe would support this statement. To the authors' knowledge this is the first reported case of hydroureteronephrosis secondary to uterine torsion in any species.     

Isolation and genotyping of Campylobacter species from kiwi (Apteryx spp.) in captivity: implications for transmission to and from humans

Aims: To investigate the presence of Campylobacter spp. in captive kiwi (Apteryx spp.) and compare their genotypic profiles with those of human and animal origin, in order to assess their potential for zoonotic or zooanthroponotic transmission.

Methods: Conventional selective enrichment and filter-based isolation methods were applied to isolate Campylobacter spp. from fresh faecal samples from 12 North Island brown kiwi (Apteryx mantelli) and one great spotted kiwi (A. haastii), housed in one of five different areas in a kiwi sanctuary in Christchurch, New Zealand. Isolates were identified using multiplex PCR and 16S rRNA gene sequencing. High-resolution rapid genotyping using multiplex ligation-dependant probe amplification-based binary typing (MBiT) was applied and profiles compared with similar results from 2,165 Campylobacter spp. isolates contained in a database derived from human clinical, veterinary and environmental samples.

Results: One isolate of C. jejuni, and one belonging to the C. lari phylogenetic group were recovered from faeces from two kiwi. High-resolution rapid genotyping by MBiT demonstrated these to be indistinguishable from isolates obtained previously from human cases of diarrhoea, and others from chicken, cattle, sheep and water.

Conclusions: These data provide evidence for potential zoonotic or zooanthroponotic transmission of Campylobacter spp. in kiwi with implications for management of birds kept in captivity. We believe this is the first formal report of C. jejuni and a C. lari-like organism in kiwi.

Abbreviations: MBiT: Multiplex ligation-dependant probe amplification-based binary typing     

Persistent isolated hypocortisolism following brief treatment with trilostane

A 12‐year‐old male neutered Miniature Poodle with confirmed pituitary‐dependent hyperadrenocorticism was treated with trilostane. After three doses, it developed clinical and laboratory changes suggestive of isolated hypocortisolism (‘atypical hypoadrenocorticism’), which persisted and progressed for more than 3 months despite immediate withdrawal of the trilostane. The clinical signs of hyperadrenocorticism resolved without further trilostane. After 3 months, prednisolone treatment was started and the clinical signs of hypocortisolism resolved. Prednisolone therapy was required for more than 1 year. Ultrasonography initially demonstrated large hypoechoic adrenal cortices, typical of dogs with hyperadrenocorticism, which then became small and heteroechoic, consistent with the development of adrenal necrosis. Persistent isolated hypocortisolism has not been reported previously as a complication of trilostane therapy. The case is also remarkable for the very short duration of trilostane therapy that elicited this complication. Clinicians should be aware that trilostane therapy may result in adrenal necrosis, even in the very earliest stages of therapy, but prompt action can prevent a life‐threatening situation.     

Prospective evaluation of pancarpal arthrodesis for carpal injuries in working dogs in New Zealand,using dorsal hybrid plating

Abstract

AIM: To determine whether working dogs in New Zealand with carpal injuries and treated with unilateral pancarpal arthrodesis (PCA), using a dorsal hybrid-plating method, are able to return to satisfactory working ability.

METHODS: Fourteen working dogs presented to the Veterinary Specialist Group (VSG) and the Massey University Veterinary Teaching Hospital (MUVTH) with carpal injuries were prospectively treated using dorsal hybrid plating. Dogs were eligible if actively involved in farm, hunting or police work. Dogs had a standardised PCA surgical procedure performed, and similar instructions for post-operative care were provided. Dogs were re-evaluated clinically and radiographically at 6 weeks, 6 months, and 12 months after surgery. A questionnaire was completed by 12 owners, to assess each dog's working ability.

RESULTS: Twelve months following arthrodesis, 10/12 (83%) dogs could perform most or all duties normally. Eleven owners (92%) reported that the result of the surgery met their expectations, and nine owners (75%) were very satisfied with the outcome of the surgery. No owners were disappointed or very disappointed with the surgical outcome. Post-operative complications requiring surgical removal of the implant occurred in three (25%) dogs.

CONCLUSIONS: Unilateral PCA using a standardised surgical procedure and dorsal hybrid plating of carpal injuries has a good prognosis for working dogs in New Zealand to return to work.

CLINICAL RELEVANCE: These results may allow veterinarians to provide a more accurate prognosis to owners of working dogs that have debilitating carpal injury     

Dominant expression of interleukin-8 vs interleukin-1β and tumour necrosis factor alpha in lungs of lambs experimentally infected with Mannheimia haemolytica

Abstract

AIMS: To quantify the number of cells infected with Mannheimia haemolytica and expressing interleukin (IL)-1β, tumour necrosis factor alpha (TNFα) and IL-8 using immunohistochemistry, and to measure the immunoreactivity of cytokines in pulmonary tissue extracts using ELISA, in the lung of lambs experimentally infected with M. haemolytica, and to compare the patterns of expression of cytokines in airways at different times post-infection (p.i.).

METHODS: Twenty 3-month-old lambs of both sexes were randomly assigned to two groups, viz infected (n=15), and uninfected controls (n=5). Each lamb in the infected group was inoculated with 1.5 x 10⁹ cfu M. haemolytica in 5 mL sterile nutrient broth, control lambs were inoculated with 5 mL sterile nutrient broth and clinical signs were monitored. Infected and control animals were killed at 1, 3, 5, 7, and 15 days p.i. Histopathology and immunohistochemistry were conducted to determine the number of immunolabelled cells in pneumonic lungs, and study the pattern of expression of IL-1β, TNFα and IL-8 in lung extracts using ELISA.

RESULTS: Lesions in bronchi and bronchioles ranged from epithelial desquamation to bronchiolitis obliterans and necrosis. The alveoli had areas of seroproteinaceous fluid, fibrin and bacterial aggregates that evolved to foci of pyogranulomatous inflammation with clustered inflammatory cells, referred to as ‘oat cells’. M. haemolytica antigen was observed in the cytoplasm of inflammatory cells. Labelling of IL-1β, TNFα and IL-8 was observed in bronchial and bronchiolar epithelial cells, alveolar exudate, and in interstitial inflammatory infiltrate, with increased expression on 1 and 3 days p.i. for IL-1β and TNFα, and 1, 3, and 5 days p.i. for IL-8. In lung tissue extracts, peak concentrations of IL-1β (55 (SD 5) ng/mL), TNFα (92 (SD 6) pg/mL) and IL-8 (8 [SD 2] μg/mL) occurred at 3 days p.i.

CONCLUSIONS: The results of this study suggested that the inflammatory cytokines IL-1β, TNFα and IL-8 may play an important role in enhancing the biological response to M. haemolytica, and contribute to the development of lesions in the lung in pulmonary pasteurellosis in sheep. Given that the expression of IL-8 in lung was much greater than that of IL-1β and TNFα, anti-cytokine agents directed at this mediator could be useful in the prevention and treatment of this disease.     

Exertional heat illness: a review of the syndrome affecting racing Thoroughbreds in hot and humid climates

Metabolic heat produced by Thoroughbred racehorses during racing can rapidly elevate core body temperature (1°C/min). When environmental conditions are hot and humid, the normal physiological cooling mechanisms become ineffective. The heat accumulated may exceed a critical thermal maximum (estimated to be 42°C), which may trigger a complex pathophysiological cascade with potentially lethal consequences. This syndrome has been labelled exertional heat illness (EHI). EHI is described in humans, but has not been well documented in Thoroughbred racehorses. The clinical signs described in racehorses would suggest that the pathophysiological events affecting the central nervous (CNS) and gastrointestinal systems are similar to those described in humans. Clinical signs are progressive and include signs of endotoxaemia and increasing levels of CNS dysfunction. Initially, horses that may be mildly irritable (agitated, randomly kicking out) may progress to unmanageable (disorientation, severe ataxia, falling) and ultimately convulsions, coma and death. Currently, the approach to treatment is largely empirical and involves rapid and effective cooling, administration of drugs to provide sedation, administration of non‐steroidal anti‐inflammatory drugs to ameliorate the effects of endotoxaemia and glucocorticoids to stabilise cell membranes and reduce the effects of inflammation on the CNS. This review provides an overview of the current knowledge about EHI in Thoroughbred racehorses, suggests a likely pathophysiology of the syndrome in horses based on the current literature on heat illness in humans and horses, and outlines current treatment strategies being used to treat racehorses with clinical signs of EHI.     

Anti‐Müllerian Hormone in the Domestic Dog during the Anestrus to Oestrous Transition

The reproductive cycle of the domestic dog features a long period of relative ovarian inactivity or anestrus. The mechanism of anestrous termination/oestrous resumption is not yet fully understood, which presents a challenge to the development of oestrous induction protocols. In this study, we assess the possibility that anti‐Müllerian hormone (AMH) might play a role in this transition by characterizing its patterns of expression in the circulation during the transition from anestrus to oestrous and in all stages of ovarian follicular growth. Serum samples from five beagles (2.0–4.5 years) were collected three times per week at least 30 days prior to the onset of oestrous and assessed for AMH concentrations. Serum AMH concentration increased significantly during the transition from anestrus to proestrus and then declined back to the anestrous baseline beginning on day ?4 before the luteinizing hormone surge, which was determined by changes in serum progesterone concentrations. Cortical sections of ovaries from females undergoing routine ovariohysterectomy (aged 8 months–5 years, n = 4) were evaluated for AMH by immunohistochemistry. Pre‐antral and small antral follicles were most strongly immunoreactive for AMH. These data suggest that the increase in the number of antral follicles is associated with the rise in serum AMH as the anestrous period comes to an end. The rise in AMH might be useful in predicting the onset of oestrus and therefore assist with the optimization of oestrous induction protocols and possibly other assisted reproductive technologies.