Validation of ultrasonography in detecting structural disease of the urogenital tract of the koala,Phascolarctos cinereus

A retrospective review of case records of ultrasonography and necropsy outcomes of 62 koalas was used to investigate the accuracy of ultrasonography in assessing koala urogenital tract structural disease at the Port Macquarie Koala Hospital. The results showed high concordance, supporting ultrasonography as an effective tool for evaluating structural disease of the koala urogenital tract, most commonly seen with chlamydiosis. The study also illustrates the advances benefiting animal welfare that can be made by wildlife carer groups through using a scientific, evidence‐based approach.     

Neural angiostrongylosis in three captive rufous bettongs (Aepyprymnus rufescens)

Neurological disease attributed to migration of the rat lungworm ( Angiostrongylus cantonensis ), is described in three captive rufous bettongs ( Aepyprymnus rufescens ). Clinical signs, including ascending paralysis and multifocal neurological deficits, were similar to those seen in other species. Histologically, the severity of meningoencephalomyelitis ranged from mild to moderate. In one animal cerebrospinal fluid contained a high percentage of eosinophils but peripheral blood cell counts were within normal limits. Treatment with dexamethasone, diazepam and vitamin E was unsuccessful. The prognosis for bettongs with this disease is poor. The susceptibility of this species to this disease has implications for enclosure design.     

Acceptance by stoats (Mustela erminea) of 1080 (sodium monofluoroacetate) in small-volume baits and its effect on behaviour and time to death

AIMS: To assess whether stoats (Mustela erminea) would eat small baits containing 0.1% sodium monofluoroacetate (1080); whether they would die from it; how long it would take to kill them; and to document the behaviour of 1080-intoxicated stoats.

METHODS: Stoats were offered 1-g baits of two semi-fluid formulations containing 0.1% 1080, presented in open dishes, and their subsequent behaviour was monitored by video and direct observation. Muscle samples from stoats that died were analysed for 1080 residues.

RESULTS: There was no significant difference between two types of bait with regard to acceptance, mortality, and time to death, and behavioural effects were similar; consequently, results from the two types of bait were combined. Twelve of 14 stoats offered the baits ate them voluntarily, and a 13th licked bait off its fur; all 13 died between 1 h 15 min and 4 h 7 min (mean 2 h 38 min) later. At first (range 29 min — 2 h 7 min, mean 1 h 1 min), their behaviour appeared to be normal. Ataxia and hyperactivity were the first behavioural signs of poisoning, and lasted 2 min — 1 h 40 min (mean 26 min). This was followed by recumbency with convulsions and rapid breathing (range 16 min to 2 h, mean 58 min), then recumbency with limited activity and progressively shallow breathing prior to death (range 1–51 min, mean 33 min). Stoats became non-responsive to a light being turned on, or to touch once recumbency became sustained.

Residues of 1080 were found in muscle tissue of all 13 dead stoats, at concentrations ranging from 0.075 μg/g in a 287-g male that died 4 h 7 min after eating only 0.74 g of bait, to 2.5 μg/g in a 254-g female that died 2 h 42 min after taking a whole 1-g bait.

CONCLUSION: Stoats will voluntarily take small (1-g) baits containing a lethal dose of 1080 at 0.1%, and die from it comparatively rapidly for a mammalian carnivore.     

Bat activity affected by sewage effluent in Irish rivers

Bat activity and benthic macroinvertebrates were sampled at nine paired sites, upstream and downstream from sewage effluent discharges into Irish rivers. Bat activity was measured using broadband acoustic detectors and macroinvertebrates by three 30-s standard benthic kick samples per site. Biological indices of water quality were significantly lower downstream from sewage outfalls, relative to upstream. The soprano pipistrelle (Pipistrellus pygmaeus) was significantly more active (as measured by bat passes per unit time) at downstream sites, while Daubenton’s bat (Myotis daubentonii) was less active. These results contrast with those of a similar study in England, where P. pygmaeus were less active, and Myotis spp. were more active downstream from sewage outfalls. We suggest that P. pygmaeus were more active downstream in our study because of a preference for preying on small orthocladiinid Chironomidae (non-biting midges), which were significantly more abundant downstream. M. daubentonii may prefer Trichoptera (caddis fly), which were significantly more abundant upstream. Organic pollution may then affect bats, but its effect appears to be more complex than previously implied. Implications of changing nutrient levels in freshwaters for populations of M. daubentonii and P. pygmaeus may be different from what is currently suggested in the literature.     

Wild fallow deer (Dama dama) as definitive hosts of Fasciola hepatica (liver fluke) in alpine New South Wales

To determine the extent to which wild deer are contributing in the transmission of Fasciola hepatica (liver fluke) livers from deer shot by hunters, farmers undertaking population control on their farms and vertebrate pest controllers were collected and frozen. The livers were later thawed, sliced and examined for the presence of adult flukes or evidence of past infection. Livers from 19 deer were examined (18 fallow [Dama dama] and one sambar [Rusa unicolor]). Seventeen of the fallow deer were animals collected on farms near Jindabyne, New South Wales. The remaining fallow deer was collected in the Australian Capital Territory and one sambar deer was collected in north-eastern Victoria. Nine of the 17 deer (53%) from the Jindabyne area were either infected with Fasciola hepatica (liver fluke) or had thickened bile ducts indicating past infection. Infection levels in the infected animals varied widely from 3 liver fluke to over 50 per liver. No sign of infection was present in the deer from the Australian Capital Territory or Victoria. Fallow deer are wide-spread in the Jindabyne area and their population is increasing. It is likely their contribution to the maintenance and distribution of F. hepatica to livestock in the Jindabyne area, and in other livestock rearing areas of south-eastern Australia, is important and increasing.