Seasonal oestrous cycle activity of captive female koalas in south-east Queensland

2015 ◽  
Vol 37 (2) ◽  
pp. 245 ◽  
Author(s):  
K. Ballantyne ◽  
A. Lisle ◽  
A. Mucci ◽  
S. D. Johnston
Keyword(s):  
Resource Availability ◽  
Food Resource ◽  
Reproductive Function ◽  
Genetic Management ◽  
Confounding Effect ◽  
Influence Of Temperature ◽  
Reproductive Management ◽  
Captive Populations ◽  
Autumn And Winter ◽  
Sexually Mature

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.

scholarly journals Pre-Columbian soil fertilization and current management maintain food resource availability in old-growth Amazonian forests

2020 ◽  
Vol 450 (1-2) ◽  
pp. 29-48 ◽  
Author(s):  
Carolina Levis ◽  
Marielos Peña-Claros ◽  
Charles R. Clement ◽  
Flavia R. C. Costa ◽  
Rubana Palhares Alves ◽  
...  
Keyword(s):  
Resource Availability ◽  
Food Resource ◽  
Old Growth ◽  
Current Management ◽  
Soil Fertilization ◽  
Amazonian Forests

Preface to the proceedings of the workshop on genetic management of captive populations

Zoo Biology ◽  
1986 ◽  
Vol 5 (2) ◽  
pp. 81-86 ◽  
Author(s):  
Katherine Ralls ◽  
Jonathan D. Ballou
Keyword(s):  
Genetic Management ◽  
Captive Populations

scholarly journals Cattle adapted to tropical and subtropical environments: genetic and reproductive considerations

2020 ◽  
Vol 98 (2) ◽  
Author(s):  
Reinaldo F Cooke ◽  
Rodolfo C Cardoso ◽  
Ronaldo L A Cerri ◽  
G Cliff Lamb ◽  
Ky G Pohler ◽  
...  
Keyword(s):  
United States ◽  
Bos Indicus ◽  
Reproductive Function ◽  
Fixed Time ◽  
The United States ◽  
Beef Industry ◽  
Tropical Regions ◽  
Reproductive Management ◽  
Adaptation Response ◽  
Equine Chorionic Gonadotropin

Abstract Efforts to understand biological functions and develop management schemes specific to Bos indicus-influenced cattle raised in tropical and subtropical environments are critical to meet the increasing global demand for protein. In the United States, B. indicus breeds are mostly used to generate B. indicus × B. taurus crosses with increased thermal and parasite tolerance, while retaining some productive characteristics of B. taurus cattle. Although crossbreeding represents a proven strategy to improve cattle adaptation almost immediately, research has also attempted to identify B. taurus genetics that can withstand subtropical and tropical climates. Reduced milk production and delayed reproductive maturation appear to be related with tropical adaptation of B. taurus breeds, as a means to conserve energy under stressful conditions and limited nutrition. Moreover, longevity may be the ultimate adaptation response to unfavorable environments, and retention of bulls and heifers from proven cows is the recommended strategy to improve longevity in B. indicus-influenced herds. Besides selection for longevity, other aspects should be considered when planning reproductive management in tropical and subtropical regions. Bos indicus and B. taurus breeds have multiple differences pertaining to reproductive function, including age at puberty, ovarian dynamics, and pregnancy development. Nutritional strategies such as the stair-step regimen, and use of exogenous progesterone (P4) inserts are options to hasten puberty attainment of late-maturing B. indicus-influenced heifers. Yet, limited pharmacological alternatives are available for reproductive management of B. indicus-influenced females in the United States, which rely on GnRH-based protocols not specifically designed to the reproductive function of B. indicus breeds. In contrast, hormonal protocols based on exogenous P4, estradiol esters, and equine chorionic gonadotropin are available for use in B. indicus females in South America. These include protocols tailored to prepubertal heifers, anestrous cows, and cycling nulliparous or parous females, which often yield pregnancy rates of 50% to fixed-time artificial insemination. The global dairy industry also faces similar challenges in increasing demand and production as the beef industry. Selection of cows capable of sustaining optimal milk yield, reproductive success, and health status in hot and humid conditions is essential for optimal dairy production in subtropical and tropical regions.

Food resource availability for American black ducks wintering in southern New Jersey

2011 ◽  
Vol 76 (1) ◽  
pp. 214-219 ◽  
Author(s):  
Dane M. Cramer ◽  
Paul M. Castelli ◽  
Tina Yerkes ◽  
Christopher K. Williams
Keyword(s):  
New Jersey ◽  
Resource Availability ◽  
Food Resource ◽  
American Black

Genetic management of captive populations: the advantages of circular mating

2010 ◽  
Vol 11 (6) ◽  
pp. 2289-2297 ◽  
Author(s):  
Konstantinos Theodorou ◽  
Denis Couvet
Keyword(s):  
Genetic Management ◽  
Captive Populations

Patterns of grassland productivity, composition and seed abundance, and the diet of the flock bronzewing pigeon Phaps histrionica at one site in northern Australia over a period of marked seasonal change

2014 ◽  
Vol 41 (4) ◽  
pp. 343 ◽  
Author(s):  
P. L. Dostine ◽  
J. C. Z. Woinarski ◽  
B. Mackey ◽  
H. Nix
Keyword(s):  
Remote Sensing ◽  
Community Structure ◽  
Plant Species ◽  
Dietary Patterns ◽  
Resource Availability ◽  
Conservation Management ◽  
Food Resource ◽  
Food Plant ◽  
Seed Density ◽  
Grassland Community

Context Multiple scales of research are needed to understand the ecology and conservation requirements of species whose ecology is characterised by marked spatial and temporal dynamism. The flock bronzewing pigeon may provide a model for the conservation management of species with similar dispersive ecologies. Aims This study aimed to document the species composition and its variability in seeds consumed by flock bronzewing pigeons across a period of contrasting seasonal conditions, and to relate this diet to variation in food resource availability. Methods The diet of the flock bronzewing pigeon was described by analysis of the crop contents of samples collected over the period from June 2006 to September 2007 at one pastoral property on the Barkly Tablelands, Northern Territory. Variation in food resource availability was assessed using data from remote sensing, grassland community structure, and direct measurement of soil seed density. Multivariate statistical methods were used to test variation in plant community structure between years and among land units; generalised linear modelling was used to examine inter-annual variation in the abundance of key food plant species and seasonal variation in seed abundance. Key results Across the period of this study, the diet of flock bronzewing pigeons on the Barkly Tableland was largely restricted to seeds of a small number of plant species within Mitchell grasslands. Dietary patterns varied between years; evidence from remote sensing, grassland community structure, and seed density was consistent with these dietary patterns. Conclusions Flock bronzewing pigeons appear to be adapted to exploiting rare, episodic events, leading to high seed production by the ephemeral or annual component of perennial tussock grasslands. Key food plant species include the forbs Wedelia asperrima, Trichodesma zeylanicum and Phyllanthus lacerosus and the large-seeded annual grass Chionachne hubbardiana. These species may not be those that provide critical resources during unfavourable periods. Implications Conservation management of flock bronzewing pigeons will entail strategies to maintain key food species in grazed landscapes, and to ensure replenishment of seed reserves of annual and ephemeral plant species. Management practices to achieve these goals may include rotational wet season spelling of paddocks. More information is required on the focal areas for persistence within these black-soil grassland landscapes.

Sign in / Sign up

Export Citation Format

Share Document