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Upper Coomera, Australia

Hogan L.A.,University of Queensland | Johnston S.D.,University of Queensland | Lisle A.T.,University of Queensland | Keeley T.,Taronga Western Plains Zoo | And 4 more authors.
Applied Animal Behaviour Science | Year: 2011

The response of animals to handling by humans has been extensively evaluated in domesticated livestock, but rarely examined in wildlife species. Twelve captive wombats (Lasiorhinus latifrons) were subjected to two treatments in a replicated design: (1) daily handling, involving 15 min of tactile contact 5 d/wk for 12 wk and (2) no-handling, involving no contact apart from that received during routine husbandry. The effect of handling was assessed via overt responses to human approach and touch, a stressor, and a novel stimulus. Daily handling reduced the wombat's flight distance in response to human approach; more in the first handling replicate (-0.16 ± 0.02 m/wk) than in the second (-0.06 ± 0.02 m/wk). A behavioural reactivity score also declined faster in the first than second handling replicate. Synthetic ACTH was used to validate the measurement of faecal cortisol metabolites in L. latifrons by EIA. Faecal cortisol metabolite secretion consistently increased in reaction to a handling procedure involving forced human contact (indicating a lack of habituation) but the magnitude of this response was not reduced by regular handling. Regular handling therefore changed the human-wombat relationship by lowering reactivity to and avoidance of the human handler, but did reduce the stress response, suggesting that the wombats entered into a state of learned helplessness. © 2011 Elsevier B.V. Source

Ballantyne K.,University of Queensland | Lisle A.,University of Queensland | Mucci A.,Dreamworld | Johnston S.D.,University of Queensland
Australian Mammalogy | Year: 2015

This study investigated the seasonality of behavioural oestrus in a captive koala population in south-east Queensland. A total of 33 sexually mature koalas were examined over a 4-year period (2009-12) to determine the possible influence of temperature, photoperiod and rainfall on the incidence of expression of behavioural oestrus without the confounding effect of lactation or limiting food resource availability. Although signs of behavioural oestrus were detected throughout the year, an obvious seasonality was apparent, with significantly fewer females displaying behavioural oestrus in late autumn and winter (May-August) than September to April (P<0.0001). While average monthly photoperiod (P<0.0001) and average monthly temperature (P<0.0001) were significantly related to oestrous behaviour, rainfall was not (P>0.05). A better understanding of the seasonality of reproductive function in the female koala will facilitate the use of reproductive management-assisted breeding technology to enable improved genetic management in captive populations. © Australian Mammal Society 2015. Source

Johnston S.D.,University of Queensland | Rumph C.,University of Queensland | Lucht M.,University of Queensland | Stenrel D.,Queensland University of Technology | And 3 more authors.
Australian Zoologist | Year: 2010

Despite its vulnerable conservation status there is scant information on male Greater Bilby Macrotis lagotis reproduction. Observations of gross anatomy revealed a testis to body weight ratio of 0.08 - 0.17% (n = 4), the presence of a carrot shaped prostate with an oblique coronal segmentation of ventral and dorsal orientated prostatic tissue, an elongated membranous urethra, two bulbourethral glands and a bifurcated urethra in the glans penis (n = I).The testis contained a high proportion of Leydig tissue (37.5 ± 2.7%) and a seminiferous epithelial cell cycle (8 stages identified) with a predominance of pre-meiotic stages (61.4%) and Sertoli cells with unusually large nuclei. A GnRH stimulation test conducted on four different intact sexually mature Bilbies using 2μg Buserelin resulted in maximal plasma androgen secretion 30 to 60 mins after injection. While steps of M. lagotis spermiogenesis were similar to those described in peramelid marsupials, the morphology of the Bilby spermatozoan at spermiation,was radically different to that of the bandicoot sperm cell. Similar to the bandicoot, M. lagotis spermatozoa in the corpus epididymidis dislocated their neck insertion from the primary implantation fossa, so that by the time the sperm cell had reached the cauda epididymidis, the acetabulum had migrated cranially Into a secondary implantation fossa and the nucleus had become streamlined with respect to the flagellum.This study reports the first description of large crystalloid inclusions in the principal cells of the caput epididymidal epithelium, the significance of which remains unknown. Male Bilby reproduction reported in this study supports the present taxonomic position of the Thylacomyidae. Source

Seddon J.M.,University of Queensland | Lee K.E.,University of Queensland | Johnston S.D.,University of Queensland | Nicolson V.N.,Dreamworld | And 3 more authors.
Wildlife Research | Year: 2014

Context Captive breeding for release back to the wild is an important component of ex situ conservation but requires genetic diversity that is representative of the wild population and has the ultimate goal of producing ecologically sustainable and resilient populations. However, defining and testing for representativeness of captive populations is difficult. Koalas (Phascolarctos cinereus) are bred for educational and tourism purposes in zoos and wildlife parks in South-East Queensland, but there are drastic declines evident in some wild koala populations in this region.Aim We compared genetic diversity at microsatellite loci and mitochondrial DNA in two captive koala populations with that of the local, wild koalas of South-East Queensland, determining the degree to which genetic diversity of neutral loci had been preserved and was represented in the captive populations.Key results The expected heterozygosity and the allelic richness was significantly greater in one captive colony than one wild South-East Queensland population. There was low but significant differentiation of the captive from wild populations using FST, with greater differentiation described by Jost's Dest. In contrast, a newly introduced Kullback-Leibler divergence measure, which assesses similarity of allele frequencies, showed no significant divergence of colony and wild populations. The captive koalas lacked many of the mitochondrial haplotypes identified from South-East Queensland koalas and possessed seven other haplotypes.Conclusions Captive colonies of koalas have maintained levels of overall neutral genetic diversity similar to wild populations at microsatellite loci and low but significant differentiation likely resulted from drift and founder effects in small captive colonies or declining wild populations. Mitochondrial DNA suggests that captive founders were from a wider geographic source or that haplotypes have been lost locally.Implications Overall, tested captive koalas maintain sufficient microsatellite diversity to act as an in situ reservoir for neutral genetic diversity of regional populations. © CSIRO 2014. Source

Allen C.D.,University of Queensland | De Villiers D.L.,U.S. Environmental Protection Agency | Manning B.D.,U.S. Environmental Protection Agency | Dique D.S.,U.S. Environmental Protection Agency | And 14 more authors.
Reproduction, Fertility and Development | Year: 2010

The effects of breeding season (late spring to early autumn) on south-east Queensland male koala fertility were examined to improve the efficacy of the AI procedure and to determine the practicality of using free-range animals as semen donors for a genome resource bank. Seasonal changes in male koala reproductive function were assessed in a wild free-range population (n = 14; obtained every 6 weeks from January to November 2005), a necropsied healthy wild population (n = 84; obtained monthly from September 2004 to August 2005) and a captive population (n = 7; obtained monthly from October 2005 to October 2006). Reproductive parameters investigated included bodyweight, coat score, sternal gland area and activity, testosterone secretion, reproductive anatomy volume and semen quality (before and after cryopreservation). Collectively, these findings show that reproduction in male koalas from south-east Queensland changes seasonally and that winter appears to be the optimal season in which to collect semen samples by electroejaculation. While it was possible to repeatedly collect semen from free-range koalas for future genetic management via potential storage in a genome resource bank, the survival of these spermatozoa after cryopreservation was poor and will require further improvement. © 2010 CSIRO. Source

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