scholarly journals EFFECT OF TOOTH WEAR ON THE RUMINATION-LIKE BEHAVIOR, OR MERYCISM, OF FREE-RANGING KOALAS (PHASCOLARCTOS CINEREUS)

2003 ◽  
Vol 84 (3) ◽  
pp. 897-902 ◽  
Author(s):  
M. Logan
Keyword(s):  
Tooth Wear ◽  
Phascolarctos Cinereus ◽  
Free Ranging

The association of tooth wear with sociality of free-ranging male koalas (Phascolarctos cinereus Goldfuss)

2002 ◽  
Vol 50 (6) ◽  
pp. 621 ◽  
Author(s):  
Murray Logan ◽  
Gordon D. Sanson
Keyword(s):  
Life History ◽  
Adult Male ◽  
Reproductive Effort ◽  
Radio Telemetry ◽  
Tooth Wear ◽  
Phascolarctos Cinereus ◽  
Free Ranging

The sociality (as measured by the degree of bellowing and amount of tree use) of five adult male koalas and one sub-adult male koala (Phascolarctos cinereus), with varying degrees of tooth wear, were investigated using acoustically sensitive radio-telemetry. Initial increases in tooth wear that coincide with an increase in age to maturity were associated with an increase in reproductive effort. Advanced tooth wear was found to be associated with a decrease in reproductive effort. This trend in reproductive effort is consistent with life-history predictions, and suggests that tooth wear has the potential to impose limitations on the reproductive longevity and fecundity of free-ranging male koalas.

Loss of tooth-supporting bone in the koala (Phascolarctos cinereus) with age

2011 ◽  
Vol 59 (1) ◽  
pp. 49 ◽  
Author(s):  
Elizabeth F. Lee ◽  
Srinivas Varanasi ◽  
Lyndall M. Pettett ◽  
Philip S. Bird ◽  
Anne L. Symons
Keyword(s):  
Bone Loss ◽  
Alveolar Bone ◽  
Age Groups ◽  
Tooth Wear ◽  
Bone Defects ◽  
Third Molars ◽  
Phascolarctos Cinereus ◽  
Severe Bone Loss ◽  
Free Ranging ◽  
Bone Height

This study investigated changes in alveolar bone height in free-ranging koalas of different age groups. Twenty-seven free-ranging Queensland koalas (15 female, 12 male), admitted to the Moggill Koala Hospital, Brisbane, were used in this study. Koalas were divided into three groups (young, adult, old) on the basis of tooth wear, each group containing nine animals. Defleshed jaws were examined for the presence of alveolar bone defects. The distance from the cemento-enamel junction and the interproximal crestal alveolar bone height was measured on the buccal aspects of the second and third molars. Jaws were photographed and radiographed. Bone defects (dehiscences and fenestrations) were observed in both jaws and were predominantly located on the buccal aspect of the alveolar process. The loss of height of crestal alveolar bone, relative to the cemento-enamel junction, increased with age, with 25 koalas showing moderate to severe bone loss and only two koalas having none/mild loss levels at all measurement sites. Female koalas had higher frequency of ‘none/mild’ cases of bone loss than did males. There was no variation in levels of alveolar bone loss between the upper and lower jaws or the corresponding right and left arches.

The effects of lactation on the feeding behaviour and activity patterns of free-ranging female koalas (Phascolarctos cinereus Goldfuss)

2003 ◽  
Vol 51 (4) ◽  
pp. 415 ◽  
Author(s):  
M. Logan ◽  
G. D. Sanson
Keyword(s):  
Feeding Behaviour ◽  
Radio Telemetry ◽  
Activity Patterns ◽  
Tooth Wear ◽  
Phascolarctos Cinereus ◽  
Active Time ◽  
Compensation Mechanisms ◽  
Lactating Females ◽  
Time Spent Feeding ◽  
Free Ranging

The free-ranging feeding behaviour and activity patterns of three lactating and two non-lactating female koalas (Phascolarctos cinereus) were investigated using acoustically sensitive radio-telemetry. Lactating females were found to consume more leaf material, masticate more per leaf and at a greater rate, and perform more ingestive and mercyism mastications per 24 h than non-lactating females. Results suggest than female koalas are 'income breeders' that compensate for the higher energetic demands of lactation by increasing intake and, to a lesser degree, investing more in each mouthful so as to produce a shift in digesta particle size distribution in favour of more finer particles. Compared with non-lactating females, lactating female koalas were also found to spend more time moving within trees, feeding per 24 h and per bout, and less time resting and sleeping per 24 h, although the proportion of active time spent feeding was similar (~80%). This implies that female koalas adopt a 'time minimizing strategy whereby activity budgets respond to current requirements. Lactation-compensation mechanisms are compared with those reported for koalas with high tooth wear, and the capacity of aging female koalas to compensate for lactation are discussed.

The effects of tooth wear on the activity patterns of free-ranging koalas (Phascolarctos cinereus Goldfuss)

2002 ◽  
Vol 50 (3) ◽  
pp. 281 ◽  
Author(s):  
M. Logan ◽  
G. D. Sanson
Keyword(s):  
Radio Telemetry ◽  
Activity Patterns ◽  
Tooth Wear ◽  
Home Ranges ◽  
Adult Males ◽  
Large Area ◽  
Phascolarctos Cinereus ◽  
Order Of Magnitude ◽  
Low Degrees ◽  
Free Ranging

The free-ranging activity patterns of five adult males and one sub-adult male koala (Phascolarctos cinereus) with varying degrees of tooth wear were investigated using acoustically sensitive radio-telemetry. Increased tooth wear was found to be associated with a significant decrease in the amount of time spent sleeping and being inactive. Furthermore, compared with individuals with low degrees of tooth wear, individuals with high tooth wear were found to spend considerably less time moving within and between trees, and had home ranges an order of magnitude smaller. Hence, feeding compensations were found to come at the expense of other activities such as sociality and therefore have important consequences for reproductive output. Individuals with high tooth wear also spent longer feeding per bout, and spaced feeding bouts out more evenly throughout a 24-h period, thereby exhibiting reduced degrees of nocturnality. The sub-adult was found to range over a disproportionately large area and spend a relatively large amount of time moving between trees, indicative of a dispersing individual. Moreover, the activity patterns of this individual were found to differ slightly from the adult trends and were perhaps affected by the extra energetic demands associated with dispersal.

scholarly journals Prevalence of cryptococcal antigenemia and nasal colonization in a free-ranging koala population

2019 ◽  
Vol 57 (7) ◽  
pp. 848-857 ◽  
Author(s):  
Laura J Schmertmann ◽  
Alex Kan ◽  
Valentina S A Mella ◽  
Cristina M Fernandez ◽  
Mathew S Crowther ◽  
...  
Keyword(s):  
Eucalyptus Camaldulensis ◽  
Polymorphism Analysis ◽  
Nasal Colonization ◽  
Agar Culture ◽  
Phascolarctos Cinereus ◽  
South Wales ◽  
Species Complexes ◽  
Cryptococcus Spp ◽  
Free Ranging ◽  
The Relationship

AbstractCryptococcosis, caused by environmental fungi in the Cryptococcus neoformans and Cryptococcus gattii species complexes, affects a variety of hosts, including koalas (Phascolarctos cinereus). Cryptococcal antigenemia and nasal colonization are well characterized in captive koalas, but free-ranging populations have not been studied systematically. Free-ranging koalas (181) from the Liverpool Plains region of New South Wales, Australia, were tested for cryptococcal antigenemia (lateral flow immunoassay) and nasal colonization (bird seed agar culture). Results were related to environmental and individual koala characteristics. Eucalypt trees (14) were also randomly tested for the presence of Cryptococcus spp. by bird seed agar culture. In sum, 5.5% (10/181) and 6.6% (12/181) of koalas were positive for antigenemia and nasal colonization, respectively, on at least one occasion. And 64.3% (9/14) of eucalypts were culture-positive for Cryptococcus spp. URA5 restriction fragment length polymorphism analysis identified most isolates as C. gattii VGI, while C. neoformans VNI was only found in one koala and one tree. Colonized koalas were significantly more likely to test positive for antigenemia. No associations between antigenemia or colonization, and external environmental characteristics (the relative abundance of Eucalyptus camaldulensis and season), or individual koala characteristics (body condition, sex, and age), could be established, suggesting that antigenemia and colonization are random outcomes of host-pathogen-environment interactions. The relationship between positive antigenemia status and a relatively high abundance of E. camaldulensis requires further investigation. This study characterizes cryptococcosis in a free-ranging koala population, expands the ecological niche of the C. gattii/C. neoformans species complexes and highlights free-ranging koalas as important sentinels for this disease.

scholarly journals Tooth wear in captive rhinoceroses (Diceros, Rhinoceros, Ceratotherium: Perissodactyla) differs from that of free-ranging conspecifics

2014 ◽  
Vol 83 (2) ◽  
pp. 107-S1 ◽  
Author(s):  
Lucy A. Taylor ◽  
Dennis W.H. Müller ◽  
Christoph Schwitzer ◽  
Thomas M. Kaiser ◽  
Daryl Codron ◽  
...  
Keyword(s):  
Life Expectancy ◽  
Dental Health ◽  
Tooth Wear ◽  
Museum Specimens ◽  
Second Molar ◽  
Rhinoceros Unicornis ◽  
Processing Ability ◽  
Posterior Cusp ◽  
Morphological Differences ◽  
Free Ranging

Tooth wear can affect body condition, reproductive success and life expectancy. Poor dental health is frequently reported in the zoo literature, and abrasion-dominated tooth wear, which is typical for grazers, has been reported in captive browsing ruminants. The aim of this study was to test if a similar effect is evident in captive rhinoceros species. Dental casts of maxillary cheek teeth of museum specimens of captive black (Diceros bicornis; browser), greater one-horned (Rhinoceros unicornis; intermediate feeder) and white rhinoceroses (Ceratotherium simum; grazer) were analysed using the recently developed extended mesowear method for rhinoceroses. Captive D. bicornis exhibited significantly more abrasion-dominated tooth wear than their free-ranging conspecifics (p<0.001), whereas captive C. simum exhibited significantly less abrasion-dominated tooth wear, particularly in the posterior cusp of the second molar (p=0.005). In R. unicornis, fewer differences were exhibited between free-ranging and captive animals, but tooth wear was highly variable in this species. In both free-ranging and captive D. bicornis, anterior cusps were significantly more abrasiondominated than posterior cusps (p<0.05), which indicates morphological differences between cusps that may represent functional adaptations. By contrast, tooth wear gradients between free-ranging and captive animals differed, which indicates ingesta- specific influences responsible for inter-tooth wear differences. Captive D. bicornis exhibited more homogenous tooth wear than their free-ranging conspecifics, which may be caused by an increase in the absolute dietary abrasiveness and a decrease in relative environmental abrasiveness compared to their freeranging conspecifics. The opposite occurred in C. simum. The results of this study suggest that diets fed to captive browsers are too abrasive, which could result in the premature loss of tooth functionality, leading to reduced food acquisition and processing ability and, consequently, malnourishment.

Production of Milk and Nutrition of the Dependent Young of Free‐Ranging Koalas (Phascolarctos cinereus)

1998 ◽  
Vol 71 (1) ◽  
pp. 45-56 ◽  
Author(s):  
Andrew K. Krockenberger ◽  
Ian D. Hume ◽  
Steven J. Cork
Keyword(s):  
Phascolarctos Cinereus ◽  
Free Ranging

Detection of Chlamydia psittaci in free-ranging koalas (Phascolarctos cinereus): DNA hybridization and immuno-slot blot analyses

1989 ◽  
Vol 21 (1) ◽  
pp. 21-30 ◽  
Author(s):  
A.A. Girjes ◽  
B.J. Weigler ◽  
A.F. Hugall ◽  
F.N. Carrick ◽  
M.F. Lavin
Keyword(s):  
Dna Hybridization ◽  
Chlamydia Psittaci ◽  
Slot Blot ◽  
Phascolarctos Cinereus ◽  
Free Ranging
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