Journal articles on the topic 'Rhinoceroses New South Wales Reproduction'
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1
Rasko, John E. J. "Bill to ban reproduction of inmates with cancer proposed in New South Wales." Medical Journal of Australia 185, no. 10 (November 2006): 575–76. http://dx.doi.org/10.5694/j.1326-5377.2006.tb00699.x.
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Laegdsgaard, P., M. Byrne, and D. T. Anderson. "Reproduction of sympatric populations ofHeliocidaris erythrogramma andH. tuberculata (Echinoidea) in New South Wales." Marine Biology 110, no. 3 (October 1991): 359–74. http://dx.doi.org/10.1007/bf01344355.
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Falkner, I., and M. Byrne. "Reproduction of Ophiactis resiliens (Echinodermata: Ophiuroidea) in New South Wales with observations on recruitment." Marine Biology 143, no. 3 (September 1, 2003): 459–66. http://dx.doi.org/10.1007/s00227-003-1066-z.
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Dickman, CR, DH King, M. Adams, and PR Baverstock. "Electrophoretic Identification of a New Species of Antechinus (Marsupialia, Dasyuridae) in Southeastern Australia." Australian Journal of Zoology 36, no. 4 (1988): 455. http://dx.doi.org/10.1071/zo9880455.
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Two electrophoretically distinct but morphologically cryptic forms of Antechinus 'stuartii', designated 'northern' and 'southern', occur together at Kioloa on the southern coast of New South Wales. These forms are distinguished by fixed allele differences in three proteins (albumin, glycollate oxidase and mannosephosphate isomerase) and by differences in allele frequencies for transferrin, and are separated by a Nei D of 0.11. The two forms are reproductively isolated in sympatry at Kioloa by asynchrony in the timing of reproduction, and may be considered separate biological species. Northern form populations were identified by screening for albumin and transferrin in seven localities on the central coast of New South Wales north of Kioloa. Southern form populations were identified similarly in 13 localities south of Kioloa and inland along the Great Dividing Range, and at a further locality in southern Victoria. Ovulation occurs at different rates of change of photoperiod in the two species, and may ensure that reproductive isolation is maintained in all potential areas of sympatry. The northern form represents A. stuartii sensu stricto and ranges from Kioloa north into south-eastern Queensland. The southern form is an undescribed species of Antechinus that appears to be widely distributed throughout southern New South Wales and Victoria.
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Ward, D. W., and A. R. Davis. "Reproduction of the turban shell Turbo torquatus Gmelin 1791 (Mollusca : Gastropoda), in New South Wales, Australia." Marine and Freshwater Research 53, no. 1 (2002): 85. http://dx.doi.org/10.1071/mf00066.
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The Sydney turban shell Turbo torquatus is the focus of a small-scale commercial fishery in New South Wales. Effective management requires knowledge of the reproductive biology, yet this is lacking for NSW waters. The reproductive cycle was investigated at three localities on the southern New South Wales coast. Samples of T. torquatus were collected monthly at Wollongong, Ulladulla and Eden from February 1996 until August or December 1997. The reproductive cycle was investigated by three methods: monthly determination of a gonadosomatic index, estimation of oocyte size-frequency distributions and classification of female gonads into developmental stages following histological sectioning. Males and females within a population underwent synchronous gonad development and spawning. Spawning events were often protracted over a period of several months with females in various stages of gonadal development. Two spawning events occurred each year, with a spawning event in autumn–winter and another in spring–summer. These events were asynchronous among the three localities, and partial spawning appeared to be a common occurrence. Owing to variation in the timing of spawning between populations separated by a distance as small as 15 km, seasonal closures to protect spawning stocks are unlikely to be effective.
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Parer, I., and JA Libke. "Biology of the Wild Rabbit, Oryctolagus cuniculus (L.), in the Southern Tablelands of New South Wales." Wildlife Research 18, no. 3 (1991): 327. http://dx.doi.org/10.1071/wr9910327.
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Shot samples of rabbits were taken every eight weeks for two years at four sites in the Southern Tablelands of New South Wales. Age structure differed between sites. The two sites at which rabbits were controlled by poisoning had the youngest age structures; the site where rabbits were not controlled had the the oldest age structure, the lowest density, the least myxomatosis and the highest production of young per female. The seasonal percentages of males in the samples were inversely proportional to the percentages of lactating females. Rabbits that were recovering from myxomatosis had higher infestations of Graphidium strigosum than rabbits that had active myxomatosis or no symptoms. At one of the sites, rabbits with myxomatosis were shot on every sampling occasion. Differences between sites, in duration and timing of reproduction, were very small compared with differences between rabbit populations from climatically different regions of Australasia; annual production of young per female older than six months varied between sites from 23.7 to 26.5 compared with the range of 15-53 for Australasia. The percentage of pregnant females and fertile males was highest in late spring and fell to zero for 1-2 months in summer. This seasonal pattern of reproduction is intermediate between the pattern found in some high-rainfall Australasian environments, where more than 30% of the females are pregnant in all months, and the patterns in arid, semi-arid and subalpine environments, where no females are pregnant for 3-6 months of the year.
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Glen, A. S. "Population attributes of the spotted-tailed quoll (Dasyurus maculatus) in north-eastern New South Wales." Australian Journal of Zoology 56, no. 2 (2008): 137. http://dx.doi.org/10.1071/zo08025.
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The spotted-tailed quoll (Dasyurus maculatus) is an endangered marsupial carnivore endemic to eastern Australia. A paucity of information on the dynamics of wild populations has hindered conservation of the species. The population dynamics of spotted-tailed quolls were investigated in an area of unusually high abundance in north-eastern New South Wales, where density is conservatively estimated at 0.3 km−2. Sixty individual quolls were captured on 331 occasions over 22 months. Apparent survival, timing and rate of reproduction, and morphometric data were compared with those of quolls from other areas. Population models were employed to investigate patterns in the behaviour and apparent survival of quolls in the study area. The high abundance of D. maculatus identifies the study area as vital to the conservation of quolls on mainland Australia, and to the future study of the species.
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Graham, Ken J. "Distribution, population structure and biological aspects of Squalus spp. (Chondrichthyes:Squaliformes) from New South Wales and adjacent Australian waters." Marine and Freshwater Research 56, no. 4 (2005): 405. http://dx.doi.org/10.1071/mf04275.
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Four species of Squalus dogsharks, S. megalops, S. cf. mitsukurii, Squalus sp. B and Squalus sp. F inhabit shelf and upper-slope depths off New South Wales and adjacent Australian states. During fishery surveys between 1976 and 2001, distributional, size composition and reproductive data were collected for these species. Adult size classes dominated catches and, for S. megalops, heavily biased sex ratios were observed. Although no female data were available for the rarely caught Squalus sp. B, reproduction in the other three species was found to be continuous with no evidence of seasonality. Fecundity was 1–3 embryos for S. megalops, 1–5 for Squalus sp. F and 4–10 for S. cf. mitsukurii. All species are commercially exploited, contributing to the mixed species demersal trawl fishery off New South Wales. Stocks of some species are greatly depleted on the main trawling grounds, but the overall distributions of all species include large areas of lightly exploited habitat.
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Stewart, John, and Julian M. Hughes. "Longevity, growth, reproduction and a description of the fishery for silver sweepScorpis lineolatusoff New South Wales, Australia." New Zealand Journal of Marine and Freshwater Research 39, no. 4 (June 2005): 827–38. http://dx.doi.org/10.1080/00288330.2005.9517355.
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O’Reilly, Chiara. "Collecting French art in the late 1800s at the Art Gallery of New South Wales." Journal of the History of Collections 32, no. 2 (March 18, 2019): 313–25. http://dx.doi.org/10.1093/jhc/fhz006.
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Abstract From the nineteenth century, Sydney’s Art Gallery of New South Wales has been a marker of cultural ambition in Australia. This paper critically considers five large French paintings purchased at the end of the nineteenth century at significant expense by the gallery. Feted by contemporaries as examples of the French academic style, they formed part of plans to develop a representative collection to further understanding of art in the colony and, over time, they have taken on a rich role in the collective cultural memory. Through close examination of these paintings, their historical reception, criticism, reproduction and traces in the gallery’s archives this article reveals a history of taste, class and the formation of the cultural value of art. Using an object-based approach, it positions these works as evidence of changing cultural ideas within the context of a state collection to offer new insight into their status, the gallery itself, and the multiple roles of public art collections.
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Richards, J. S., M. A. Sladek, and G. J. Lee. "Cumulative reproductive performance effect on overall lifetime productivity in Merino sheep." Animal Production Science 58, no. 8 (2018): 1470. http://dx.doi.org/10.1071/an17794.
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Reproduction is an important driver of profitability in commercial sheep flocks. Historically, Merino flocks have been run with a fixed age structure, ignoring individual merit and casting for age at a specific age. More recently, research has focussed on utilising the variation within age groups by keeping productive older ewes longer and culling less productive ewes earlier. Previous studies have also examined the effect of age on reproduction and the impact of reproduction status on productivity, but little research has been conducted on cumulative effects of reproductive performance on later productivity, reproduction and health. The present study examined the impact of higher lifetime reproduction on other key production and fitness traits in older ewes run under commercial conditions. Data were collected from two commercial wool-producing properties in the South West Slopes and the Central West Plains of New South Wales during 2009–2011. Reproduction, fleece measurements, bodyweight and condition and dental health were recorded during the study. The results showed that age had a bigger effect on productivity and dental health than did cumulative lifetime reproduction. Environment and genetics determined the level of impact, with minimal loss in productivity from increased age of animals occurring in the South West Slopes flock, whereas the Central West Plains flock would appear to require closer monitoring of productivity as ewes aged. The data collected did not allow separation of the genetic and environmental influences within the study. Retaining animals with a higher reproductive performance past normal culling age does not necessarily result in reduction of productivity or ewe health, but this must be monitored.
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Byrne, M., N. L. Andrew, D. G. Worthington, and P. A. Brett. "Reproduction in the diadematoid sea urchin Centrostephanus rodgersii in contrasting habitats along the coast of New South Wales, Australia." Marine Biology 132, no. 2 (September 29, 1998): 305–18. http://dx.doi.org/10.1007/s002270050396.
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Daly, Garry. "The distribution and status of the Giant Burrowing Frog Heleioporus australiacus in the Shoalhaven region of south-eastern New South Wales." Australian Zoologist 40, no. 2 (December 2019): 256–71. http://dx.doi.org/10.7882/az.2018.011.
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Surveys were conducted for the Giant Burrowing Frog Heleioporus australiacus within 50 km of Nowra, on the south coast of New South Wales using a variety of methods. Thirty-eight 250 m transects were surveyed at night for 30 min each and 0–12 adult frogs were detected during these searches. Additional diurnal searches for tadpoles proved to be the most efficient method to detect the species and locate breeding sites. Of 102 sites surveyed, fragmented populations were found at 27 by the presence of tadpoles and adult frogs. The vegetation at these sites was woodland and open forest with a dense shrublayer of heath, but was often ecotonal. Forty-six percent of the sites were within 100 m of cliff edges/waterfalls. The lithology of sites where the frog was found varied from Hawkesbury, Nowra and Snapper Point sandstones. The exception was a population south of Ulladulla that occurs on undifferentiated sediments, but at that site exposed sandstone and a sandy overlay was present. The location of tadpoles indicated that adults were highly selective of the section of drainage line used for breeding. Often these sites consisted of a few small pools in non-perennial creeks. Breeding behaviour was associated with late summer and autumn rain, but in some sites reproduction did not occur annually. Based on distribution and habitat preference, the region has five discrete populations. Urban development has fragmented populations.
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Lee, G. J., M. A. Sladek, S. Hatcher, and J. S. Richards. "Using partial records to identify productive older ewes to retain in the breeding flock to increase the flock net reproduction rate." Animal Production Science 54, no. 10 (2014): 1631. http://dx.doi.org/10.1071/an14435.
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The reproductive performance of 7286 ewes from three Merino genetic resource flocks maintained in the central-western region of New South Wales was used to compare the use of fertility and fecundity information and net reproduction information whether recorded early (at 2 and 3 years of age) or later in life (at 4 and 5 years of age) with lifetime performance (at 2–6 years of age) as alternative selection criteria to identify productive older ewes to retain in the breeding flock. While the lifetime net reproduction rate is the best indicator of a ewe’s reproductive performance in later life, producers basing their selection decisions on pregnancy scanning data, which provides information on both fertility and fecundity, can improve the net reproduction rate of their flock by 2% regardless of the base reproduction rate. Despite little difference in likely flock reproduction rates between using early or later life scanning information as the selection criteria, early life performance is the best choice for commercial producers because it provides scope for eliminating twice-dry ewes from the breeding flock early in life, especially when combined with udder examination at marking.
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Sharp, A., M. Norton, and A. Marks. "Demography of a yellow-footed rock-wallaby Petrogale xanthopus colony in the threatened New South Wales sub-population." Australian Mammalogy 28, no. 2 (2006): 215. http://dx.doi.org/10.1071/am06030.
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The remnant New South Wales (NSW) yellow-footed rock-wallaby (Petrogale xanthopus) population underwent a substantial decline between 1985 and 1992 and remained at dangerously low levels until 1995. To determine the processes underlying this decline, a population study was conducted at one colony, between winter 1995 and winter 1998. The colony was observed to remain relatively constant in size, consisting of between 12 or 13 individuals throughout the study. Reproductive rates were found to be relatively high. Both reproduction and pouch young survival were comparable with those reported for other P. xanthopus colonies, while adult survival rates were higher than those noted in other studies. Because population size remained constant during the study and adult survivorship was consistently high, this suggested that juvenile recruitment into the colony was low. Such low levels of recruitment may have had a substantive role in the slow decline of the entire NSW P. xanthopus population. The results of this study suggest that any management actions undertaken in the NSW P. xanthopus population should focus on increasing juvenile survival rates. Further research is required to determine whether juvenile survival is constrained by predation or competition with other herbivores.
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Semeniuk, M., F. Lemckert, and R. Shine. "Breeding-site selection by cane toads (Bufo marinus) and native frogs in northern New South Wales, Australia." Wildlife Research 34, no. 1 (2007): 59. http://dx.doi.org/10.1071/wr06112.
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Previous research on cane toads (Bufo marinus) has documented non-random selection of breeding sites by this invasive species. In the wet–dry tropics of the Northern Territory, toads selected spawning sites in open areas with gently sloping banks and shallow water. If consistent, such biases may present opportunities for toad control via waterbody manipulation – but first we need to know whether such criteria for spawning-site selection (1) are consistent across other parts of the toad’s extensive Australian range, and (2) differ from those of native anurans breeding at the same waterbodies. We quantified the attributes of potential and actual spawning-sites in north-eastern New South Wales, in temperate-zone habitat where cane toads have been present for many decades; our study area thus differs in many ways from the previously studied tropical site. We compared habitat and water chemistry variables between 23 cane toad breeding sites and 23 nearby unused sites. To examine habitat use at an even finer scale, we conducted nocturnal surveys of microhabitat use by calling male toads and native anurans. Our results revealed that cane toads in this region were highly selective in their choice of breeding sites, and that the criteria they used in this respect were similar to those used by toads in the Northern Territory. Calling male cane toads also used microhabitats non-randomly within each pond, apparently based on similar criteria to those used when selecting among ponds. Toads differed significantly from native anurans in these respects, suggesting that it may be feasible to manipulate waterbody attributes to impact on invasive toads without disrupting reproduction by native anurans.
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Lee, G. J., K. D. Atkins, and M. A. Sladek. "Heterogeneity of lifetime reproductive performance, its components and associations with wool production and liveweight of Merino ewes." Animal Production Science 49, no. 7 (2009): 624. http://dx.doi.org/10.1071/an09013.
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The heterogeneity in lifetime (2–6 years of age) reproductive performance within three research flocks maintained at the Agricultural Research Centre, Trangie, in central-western New South Wales, was used to establish the potential to improve flock reproductive performance by identifying performance segments for either selection or for differential management. The data comprised a total of 32 716 records from 7322 ewes, collected over the period from 1977 to 2003. Within each of the flocks, there were large differences (P < 0.001) in lifetime net reproduction rate, and each of its components (fertility, fecundity and lamb survival), between each of the net reproduction rate quartiles. The difference in net reproduction between the ewes in the top quartile and those in the bottom quartile was equivalent to an additional lamb per ewe annually. These differences in reproduction rate between the quartiles were not related to pre-joining liveweight or condition score. Higher reproductive rates were associated with a cost to clean fleece weight, although the estimated effects on fibre diameter were small. Opportunities to use this variation to improve reproduction rates are discussed and include retaining high-performing ewes longer in the breeding flock, removing poor performers and targeting management interventions towards ewes that will yield the largest responses.
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Byrne, M. "Reproduction of sympatric populations of Patiriella gunnii, P. calcar and P. exigua in New South Wales, asterinid seastars with direct development." Marine Biology 114, no. 2 (1992): 297–316. http://dx.doi.org/10.1007/bf00349533.
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Cameron, M. "The influence of climate on Glossy Black-cockatoo reproduction." Pacific Conservation Biology 15, no. 1 (2009): 65. http://dx.doi.org/10.1071/pc090065.
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Glossy Black-cockatoos Calyptorhynchus lathami are dietary specialists, feeding almost exclusively on the seeds of Allocasuarina and Casuarina species. Their specialized diet makes them vulnerable to alterations in their food supply, and populations inhabiting variable environments are good candidates for identifying reproductive strategies that match output to the available food supply. I studied reproduction in a population of Glossy Black-cockatoos in central New South Wales, a region where rainfall varies substantially between years and which is subject to periodic drought. Seed production in the principal Glossy Black-cockatoo feed species in the region tracks rainfall, and as a consequence, the Glossy Black-cockatoo food resource fluctuates between years. I monitored nest success and population structure between 1997 and 2004, a period that included wet and dry years. There was a strong relationship between cockatoo productivity and rainfall in the preceding year. The principal determinant of annual productivity was the number of pairs attempting to breed. Increased aridity as a result of climate change will have negative consequences for inland populations of Glossy Black-cockatoos. Careful management of their habitat will be required if Glossy Black-cockatoo populations are to persist in the long term.
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Griffith, S. J., C. Bale, and P. Adam. "The influence of fire and rainfall upon seedling recruitment in sand-mass (wallum) heathland of north-eastern New South Wales." Australian Journal of Botany 52, no. 1 (2004): 93. http://dx.doi.org/10.1071/bt03108.
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Wallum heathland is extensive on coastal sand masses in north-eastern New South Wales and south-eastern Queensland. Here the climate is subtropical, although monthly rainfall is highly variable and unreliable. We examined the influence of fire and rainfall on seedling recruitment in bradysporous dry-heathland [Banksia aemula R.Br., Melaleuca nodosa (Sol. ex Gaertn.) Sm.] and wet-heathland [Banksia oblongifolia Cav., B.�ericifolia L.f. subsp. macrantha (A.S.George) A.S.George, Leptospermum liversidgei R.T.Baker and H.G. Sm.] species. Two specific questions were addressed: (1) do elevated levels of soil moisture facilitate seedling recruitment; (2) is the post-fire environment superior for seedling recruitment? Field experiments demonstrated that heathland species studied here are capable of successful recruitment in atypical habitat, and this proceeds irrespective of fire and unreliable rainfall. Conditions for growth and reproduction were found to be adequate if not more favourable in dry heathland, and this outcome included species usually associated with wet heathland. Spatial and temporal trends in seedling emergence and survival were examined in relation to post-fire predation and plant resource availability. Existing ideas about wallum management and conservation are evaluated, in particular the role of fire.
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Wright, Jan. "A Feminist Poststructuralist Methodology for the Study of Gender Construction in Physical Education: Description of a Study." Journal of Teaching in Physical Education 15, no. 1 (October 1995): 1–24. http://dx.doi.org/10.1123/jtpe.15.1.1.
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This paper describes the theoretical underpinnings and methodology of a study investigating the production and reproduction of gender in physical education lessons in three schools in New South Wales, Australia. The intention of the paper is to demonstrate how questions raised within a feminist examination of the construction of gender in physical education can be explored using both the methodology provided by a poststructuralist approach informed by Michel Foucault and the analytical tools provided by semiotics and systemic functional linguistics. Although some results of the analysis are provided, these serve more as examples of the potential of such an approach rather than as an exhaustive report of outcomes.
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Taylor, Jennifer E. "Reproduction in sympatric lizards: comparison of two species of Ctenotus (Scincidae) in south-eastern Australia." Australian Journal of Zoology 52, no. 6 (2004): 649. http://dx.doi.org/10.1071/zo04017.
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The scincid lizards Ctenotus robustus and C. taeniolatus occur sympatrically in regenerating, sand-mined areas in the Port Stephens–Myall Lakes region, coastal New South Wales, Australia. They are absent from the unmined open forest of the area. The reproductive characteristics of these two species were compared. Males reached sexual maturity at a smaller snout–vent length (SVL) than females in C. robustus (72 mm v. 78 mm) and C. taeniolatus (49 mm v. 52 mm). Males were reproductive from August to December and maximum testis volume in both species occurred in early spring; minimum testis volume was recorded in early autumn. Females of both species contained yolking follicles or eggs from October to January (spring–summer). Clutch size in C. robustus (4–9) did not differ significantly from that in C. taeniolatus (2–7) when SVL was accounted for. Both species laid eggs in nests dug 4–5 cm deep in open sandy areas with sparse vegetation, and nesting requirements might explain their absence from open forest. At hatching, C. robustus averaged 35.9 mm SVL and C. taeniolatus averaged 29.9 mm SVL. Hatchlings of both species were at field sites from mid-January to early April. Overall, reproductive characteristics of C. robustus and C. taeniolatus were generally similar.
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Winstanley, Roy K. "Morphological change and fat accumulation in juvenile red foxes (Vulpes vulpes) in the Central Tablelands of New South Wales." Wildlife Research 27, no. 5 (2000): 525. http://dx.doi.org/10.1071/wr99072.
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Juvenile red foxes (Vulpes vulpes) reach sexual maturation within 10 months of parturition. During this time juveniles need to manage their energy reserves to fuel maintenance metabolism, growth and reproduction. To determine juvenile growth rates and body energy reserves, I measured body mass, morphology, and estimated body fat, in free-living red foxes from approximately 8 weeks of age through to 1 year old. Foxes (n = 163) were sampled monthly from August 1995 to July 1996 in the Central Tablelands of New South Wales. Mean body mass of male and female juvenile foxes was indistinguishable from adult body mass by February, at 16 weeks of age (males 4500 g, females 4200 g). Skeletal measurements of body and forelimb length in both sexes also attained adult proportions by February. Further changes in morphology were minimal in first-year foxes. Total body fat was estimated indirectly using a kidney fat index. Estimated juvenile body fat remained low and stable (6%) in both sexes from December through March. Male body fat peaked in August (11%) but was low in July during mating and also September and October whilst females were denning. Estimated body fat of females peaked in August–September (13%) but declined sharply in October after parturition. In addition, 73% of first-year females sampled during August–October were either pregnant or had recently given birth.
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Higgisson, William, Linda Broadhurst, Foyez Shams, Bernd Gruber, and Fiona Dyer. "Reproductive Strategies and Population Genetic Structure in Two Dryland River Floodplain Plants, Marsilea drummondii and Eleocharis acuta." Genes 13, no. 9 (August 23, 2022): 1506. http://dx.doi.org/10.3390/genes13091506.
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Aquatic plants share a range of convergent reproductive strategies, such as the ability to reproduce both sexually and asexually through vegetative growth. In dryland river systems, floodplain inundation is infrequent and irregular, and wetlands consist of discrete and unstable habitat patches. In these systems, life history strategies such as long-distance dispersal, seed longevity, self-fertilisation, and reproduction from vegetative propagules are important strategies that allow plants to persist. Using two aquatic plants, Marsilea drummondii and Eleocharis acuta, we investigated the proportions of sexual and asexual reproduction and self-fertilisation by employing next-generation sequencing approaches, and we used this information to understand the population genetic structure of a large inland floodplain in western New South Wales (NSW), Australia. Asexual vegetative reproduction and self-fertilisation were more common in M. drummondii, but both species used sexual reproduction as the main mode of reproduction. This resulted in a highly differentiated genetic structure between wetlands and a similar genetic structure within wetlands. The similarity in genetic structure was influenced by the wetland in the two species, highlighting the influence of the floodplain landscape and hydrology on structuring population genetic structure. The high levels of genetic variation among wetlands and the low variation within wetlands suggests that dispersal and pollination occur within close proximity and that gene flow is restricted. This suggests a reliance on locally sourced (persistent) seed, rather than asexual (clonal) reproduction or recolonisation via dispersal, for the population maintenance of plants in dryland rivers. This highlights the importance of floodplain inundation to promote seed germination, establishment, and reproduction in dryland regions.
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Bomford, M. "Food and reproduction of wild house mice. 1. Diet and breeding seasons in various habitats on irrigated cereal farms in New South Wales." Wildlife Research 14, no. 2 (1987): 183. http://dx.doi.org/10.1071/wr9870183.
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The diet and breeding seasons of house mice, Mus musculus L., were monitored for 16 months in six habitats on two cereal farms: fields of barley, wheat, sorghum and rice stubble, and contour banks in rice fields, and channel banks. In all habitats mice were mainly granivorous. Because of rotational cropping and irrigation, seeds were available in different habitats in each season and this was reflected in the diets. Cereal grains spilt at harvest and other stale seeds were the main food in the nonbreeding season. It is proposed that the low quality of this food limited breeding. When milk-ripe grass seeds became available, mice switched to this fresh food, and started breeding about 1 month later. The onset of breeding was asynchronous between different habitats; this suggests that time of onset of breeding was determined by availability of food.
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Jin, Shihui, Borame Lee Dickens, Jue Tao Lim, and Alex R. Cook. "EpiRegress: A Method to Estimate and Predict the Time-Varying Effective Reproduction Number." Viruses 14, no. 7 (July 20, 2022): 1576. http://dx.doi.org/10.3390/v14071576.
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The time-varying reproduction (Rt) provides a real-time estimate of pathogen transmissibility and may be influenced by exogenous factors such as mobility and mitigation measures which are not directly related to epidemiology parameters and observations. Meanwhile, evaluating the impacts of these factors is vital for policy makers to propose and adjust containment strategies. Here, we developed a Bayesian regression framework, EpiRegress, to provide Rt estimates and assess impacts of diverse factors on virus transmission, utilising daily case counts, mobility, and policy data. To demonstrate the method’s utility, we used simulations as well as data in four regions from the Western Pacific with periods of low COVID-19 incidence, namely: New South Wales, Australia; New Zealand; Singapore; and Taiwan, China. We found that imported cases had a limited contribution on the overall epidemic dynamics but may degrade the quality of the Rt estimate if not explicitly accounted for. We additionally demonstrated EpiRegress’s capability in nowcasting disease transmissibility before contemporaneous cases diagnosis. The approach was proved flexible enough to respond to periods of atypical local transmission during epidemic lulls and to periods of mass community transmission. Furthermore, in epidemics where travel restrictions are present, it is able to distinguish the influence of imported cases.
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Clarke, PJ. "Base-Line Studies of Temperate Mangrove Growth and Reproduction; Demographic and Litterfall Measures of Leafing and Flowering." Australian Journal of Botany 42, no. 1 (1994): 37. http://dx.doi.org/10.1071/bt9940037.
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Growth and reproduction in two species of mangrove, Avicennia marina and Aegiceras corniculatum, were measured over three years in Jervis Bay, New South Wales, by demographic censuses of leaf and floral components supplemented by litterfall collections. Sampling was designed to assess spatial and temporal variability for purpose of a baseline against which future variation can be compared. In terms of annual litterfall Avicennia produces about 310 g/m2 whereas Aegiceras produces 210 g/m2 with 9.2 and 32.2 % of litterfall respectively devoted to reproductive parts. Both mangrove species showed much spatial and temporal variation in growth and reproduction and, in general, leafing and litterfall declined from 1989 through to 1990. This decline may be related to regional climatic phenomena but longer-term data are required to confirm this relationship. Over the period of a year, Avicennia and Aegiceras each has a single peak of leafing and reproduction, although the timing of this differs between them. Phenologically, in both species, reproductive events and leaf demography were correlated. It is suggested that demands of precocious embryos for assimilates affects the timing of leafing. The relatively high resource demand of the reproductive pool may also be a factor that contributes to low productivity and stature at high latitudes.
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Murray, MD. "The Seasonal Abundance of Female Biting-Midges, Culicoides-Brevitarsis Kieffer (Diptera, Ceratopogonidae), in Coastal South-Eastern Australia." Australian Journal of Zoology 39, no. 3 (1991): 333. http://dx.doi.org/10.1071/zo9910333.
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Daily light-trap collections of female C. brevitarsis were made at three localities along the northern coastal plains of New South Wales. Numbers increased during spring, were maximal in summer, declined during autumn and were minimal in winter. The generation time was about 3-4 weeks in the summer and several cohorts of nulliparous midges, probably representing different generations, were detected from spring to autumn. Some breeding continued throughout the winter. Summer abundance appeared to be associated with high rates of reproduction in late spring or early summer, and this occurred when rainfall was adequate for good pasture growth. Midge survival was better in the summer than in other seasons of the year, and numbers of parous females increased rapidly whenever it rained, probably due to their increased survival and longevity. At each locality, numbers fluctuated throughout spring, summer and autumn, with peaks and troughs of abundance which were often not obviously associated with concurrent climatic conditions or cattle movements.
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Goldingay, RL, and RP Kavanagh. "Socioecology of the Yellow-Bellied Glider, Petaurus-Australis, at Waratah-Creek, Nsw." Australian Journal of Zoology 38, no. 3 (1990): 327. http://dx.doi.org/10.1071/zo9900327.
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Aspects of the socioecology of the yellow-bellied glider were examined at Waratah Creek near Bombala in south-eastern New South Wales. Gliders lived in family groups consisting of an adult monogamous pair plus offspring. Mean group size was 2.6 individuals. Females gave birth to a single young, often in successive years. Young were only born between June and December with a pronounced peak between July and September. A food availability model was constructed and used to account for the pattern of reproduction among gliders. The onset of breeding usually occurred when exudates were abundant. Late lactation and the weaning of young (periods when the protein requirements of mother and young are likely to be greatest) coincided with summer. This was a time when the highly predictable bark shed of Eucalyptus viminalis occurred, which presumably provided an abundant arthropod (i.e. protein) resource. This breeding pattern ensured that young were foraging independently before the ensuing winter.
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Attard, S. M., and S. C. Mckillup. "Reproduction and Growth of The Bandicoot Isoodon macrourus At Four Sites in Rockhampton, Queensland." Australian Mammalogy 20, no. 3 (1998): 411. http://dx.doi.org/10.1071/am98411.
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Within Australia the northern short-nosed bandicoot, Isoodon macrourus, occurs in coastal areas from the Kimberleys to the monsoonal tropics of the Northern Territory and from Cape York Peninsula to the Hawkesbury River, New South Wales (Gordon 1983). The reproductive ecology of I. macrourus has been studied in two captive (Hall 1983; Gemmell 1988) and five natural populations (Gordon 1971, 1974; Gemmell 1982; Hall 1983; Friend 1990; Kem- per et al. 1990; Budiawan 1993). Three of the latter (Darwin, the Mitchell Plateau and Townsville) were in the tropics; breeding at these sites occurred dur- ing the wetter months of the year but not during the summer of 1982/3 in Darwin when the monsoon failed (Friend 1990) or during the relatively dry winter/spring of 1991 in Townsville (Budiawan 1993), suggesting a dependence on rainfall (Friend 1990; Budiawan 1993). We report on differences in the reproduction, growth and development of I. macrourus in Rockhampton, Queensland, from March - October 1993 at four adjacent sites which received different amounts of artificial watering.
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Boonstra, R., and TD Redhead. "Population dynamics of an outbreak population of house mice (Mus domesticus) in the irrigated rice-growing area of Australia." Wildlife Research 21, no. 5 (1994): 583. http://dx.doi.org/10.1071/wr9940583.
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Conditions appear ideal for annual plagues of house mice in irrigated rice-growing areas of Australia, yet plagues in these areas usually coincide with those in the dry farms. In an irrigated rice crop near Jerilderie, New South Wales, we examined in detail the demography of an incipient plague population of Mus domesticus. Breeding occurred from winter 1983 to autumn 1984 and the population increased from low levels to plague levels (2500 ha-1) by May. We found no evidence for a rigid territorial social organisation. Dispersal of tagged animals was low throughout the breeding season, yet between 60% and 76% of the trappable population was new each trapping session. Testosterone levels increased when the average male body weight was low, suggesting that social suppression of reproduction was not occurring. We conclude that plagues in these areas can develop within approximately 12 months from the onset of drought-breaking rains.
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Ross, PM. "Differences in morphology and reproduction of the barnacles Elminius covertus and Hexaminius spp. from mangrove forests in the Sydney region of New South Wales." Marine and Freshwater Research 47, no. 5 (1996): 715. http://dx.doi.org/10.1071/mf9960715.
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E. covertus is found on bark and leaves of the grey mangrove Avicennia marina, H. foliorum is found on leaves and H. popeiana is found on bark. 7655 barnacles were collected from two sites at Woolooware Bay from winter 1987 to summer 1989. Reproductive and external features in E. covertus differed depending on the substratum on which it lived; reproductive output was greater on leaves than on bark. The genus Hexaminius has been classified elsewhere as two species on the basis of external features and reproductive differences of adults, larval development and larval setation; however, the adults were living on different substrata. A detailed study of larval and juvenile stages of Hexaminius in the field showed no differences in external features until juveniles were one month old and no differences in the time taken to rear cyprid larvae. This suggests that Hexaminius should not continue to be divided into two species.
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Bomford, M. "Food and reproduction of wild house mice. 2. A field experiment to examine the effect of food availability and food quality on breeding in spring." Wildlife Research 14, no. 2 (1987): 197. http://dx.doi.org/10.1071/wr9870197.
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Free-ranging populations of house mice, Mus musculus L., on contour banks in a rice field in New South Wales were provided with three types of supplementary food of differing nutritional quality for 10 weeks in spring. Four live-trapping sessions were conducted 3-10 weeks after supplementary feeding started. The percentage of females breeding averaged 47% on banks with supplementary food, and 0% on control banks with no supplementary food. The quality of the supplementary food did not affect breeding performance. It is concluded that breeding in rice fields in spring is limited by the food supply, and it is probably the supply of energy, rather than that of specific nutrients, that is limiting.
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Dwyer, John M. "Reproductive size thresholds and seedling survival in Acacia harpophylla (Mimosaceae)." Australian Journal of Botany 65, no. 5 (2017): 438. http://dx.doi.org/10.1071/bt17051.
Full textAbstract:
Acacia harpophylla F.Muell. ex Benth. (brigalow) forests and woodlands formerly occupied at least 8.7 M ha of Queensland and New South Wales, but less than 10% persists in isolated fragments and linear strips within a matrix of exotic beef pasture and dryland cropping. Given the relatively rapid and widespread clearing of brigalow forests, recent research has focussed on restoration via naturally resprouting vegetation. However, our understanding of A. harpophylla sexual reproduction and seedling recruitment remains poor. This study, undertaken following a widespread masting event in late 2007, aimed to (1) quantify initial densities of A. harpophylla germinants; (2) estimate subsequent seedling survival during the first year; and (3) determine minimum size thresholds for sexual reproduction in A. harpophylla. Initial densities averaged >46 000 seedlings ha–1, but only 438 seedlings ha–1 (<1%) were estimated to remain after a year. Although mortality was high, seedling recruitment is probably still sufficient to replace senescing stems and augment population genetic diversity to some extent. A reproductive size threshold of 10 cm diameter was identified, providing useful information to predict when naturally resprouting stands will begin to participate in masting events.
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Serena, M., and T. R. Grant. "Effect of flow on platypus (Ornithorhynchus anatinus) reproduction and related population processes in the upper Shoalhaven River." Australian Journal of Zoology 65, no. 2 (2017): 130. http://dx.doi.org/10.1071/zo17025.
Full textAbstract:
The platypus (Ornithorhynchus anatinus) occupies a wide range of aquatic habitats, feeding mainly on benthic macroinvertebrates. In this study, we investigated how flow affects platypus reproduction in the unregulated upper Shoalhaven River in rural New South Wales. In a mainly dry period, the population occurred at relatively high density (12.4 animals km–1) and was strongly female-biased (84% of resident animals); mean annual loss and recruitment of resident females were respectively estimated to be 12% and 14%. Percentage lactation was 17–71% (n = 23 years), and annual reproductive success (defined as the mean number of juveniles captured per adult/subadult female from February to April) varied from 0 to 1.5 juveniles female–1 (n = 21 years). A significant positive linear relationship was evident between percentage lactation and antecedent discharge in the five months before breeding (March–July) and a positive curvilinear relationship was evident between percentage lactation and mean litter size. Conversely, reproductive success was compromised by high poststorm discharge in the period when juveniles are confined to a nesting burrow, especially from late November to early January. The relationships identified in our study between flow and reproduction also appear to apply to platypus populations occupying urban streams in Victoria, suggesting that they may be widely relevant to this species.
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Prasannath, Galea, and Akinsanmi. "Air Temperature an Influential Climatic Factor for Growth and Reproduction of Dry Flower Pathogens of Macadamia." Proceedings 36, no. 1 (January 3, 2020): 33. http://dx.doi.org/10.3390/proceedings2019036033.
Full textAbstract:
In order to assess the influence of climatic factors on abundance of conidia of dry flower pathogens, Pestalotiopsis macadamiae and Neopestalotiopsis macadamiae, a Burkard spore trap was used to determine daily aerial conidia concentration at Alstonville (28.852° S, 153.456° E), New South Wales, Australia. Weather data including minimum and maximum air temperatures, rainfall, wind speed and relative humidity were obtained from an automated weather station at the same location. The effect of each, and the combined climatic parameters on conidia abundance was analysed using the GLM procedure for the all-subset regression link functions. A model containing weekly maximum temperature and weekly rainfall produced the best significant effect on conidia abundance (R2 = 72.7%, P = 0.003) compared with the model containing daily data of both climatic parameters (R2 = 35.4%, P = 0.000). In vitro assays were established to examine the effect of different temperatures (12, 19, 22, 25, 29, 33, 37 and 41 °C) on growth and reproduction of the pathogens. The results showed that maximal mycelial growth, conidia production and germination occurred at 25 °C and declined significantly (P < 0.05) at cooler and warmer temperatures. Temperatures above 40 °C were lethal for growth and functioning of the pathogens. The results confirmed that air temperature significantly influenced growth and reproduction of both dry flower pathogens. These findings will underpin development of a disease prediction model for dry flower in macadamia.
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Henderson, Linda, Mai-Anh Ly, Katie Robinson, Frank H. Gleason, and Osu Lilje. "Maximum temperature for growth and reproduction is similar in two soil isolates of Gaertneriomyces semiglobifer (Spizellomycetales, Chytridiomycetes) from different soil environments in north eastern New South Wales, Australia." Nova Hedwigia 106, no. 3 (May 1, 2018): 485–97. http://dx.doi.org/10.1127/nova_hedwigia/2017/0448.
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Zahid, Mohammad, Michael Hodda, Geoff Gurr, William Fulkerson, Jackie Nobbs, Alexander Nikandrow, and Helen Nicol. "Effect of the clover root-knot nematode (Meloidogyne trifoliophila) on growth of white clover." Nematology 3, no. 5 (2001): 437–46. http://dx.doi.org/10.1163/156854101753250764.
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AbstractRoot-infecting nematodes are common on white clover (Trifolium repens) in dairy pastures on the north coast of New South Wales and southeastern Queensland, Australia, where they are thought to contribute to poor growth and persistence. The nematode responsible for causing root-knot symptoms on white clover was identified as Meloidogyne trifoliophila, a species not previously recorded from Australia. M. trifoliophila failed to reproduce on any of the standard North Carolina hosts used to identify M. javanica, M. hapla, M. arenaria and M. incognita , but caused severe galling and exhibited a high rate of reproduction on white clover. PCR primers for these Meloidogyne species also failed to amplify DNA of M. trifoliophila. Identity was confirmed by morphological measurements and plant symptoms. In a glasshouse test, increasing initial nematode density within the range 0 to 10 000 per 500 ml pot led to reduced shoot and root growth, fewer nodules and more severe root-knot symptoms. A second pot test screened weed species as potential alternative hosts of M. trifoliophila. None of the eight grass species was galled but M. trifoliophila reproduced on two of the eight dicotyledon weeds, spear thistle (Cirsium vulgare) and pigweed (Portulaca oleraceae).
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Molloy, David, Mary Louise Doody, and Terrence Breen. "Second time around: a study of patients seeking second assisted reproduction pregnancies**Presented at the Fertility Society of Australia Conference, Sydney, New South Wales, Australia, November 2 to 6, 1993." Fertility and Sterility 64, no. 3 (September 1995): 546–51. http://dx.doi.org/10.1016/s0015-0282(16)57790-5.
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Humphries, A. W., S. S. Robinson, D. Hawkey, D. M. Peck, T. D. Rowe, C. T. de Koning, and A. Newman. "Diversity for resistance to a moderately virulent bluegreen aphid (Acyrthosiphon kondoi Shinji) population in Trifolium species." Crop and Pasture Science 67, no. 9 (2016): 1009. http://dx.doi.org/10.1071/cp15102.
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The resistance of a diverse range of Trifolium species (clovers) to a highly virulent bluegreen aphid (BGA, Acyrthosiphon kondoi Shinji) population (Urrbrae 2011) collected in South Australia was assessed in greenhouse and field experiments, with the aims of determining the potential impact of this insect pest on biomass and identifying resistant genotypes for future plant-breeding activities. Resistance to BGA was found in populations of clovers that show some level of outcrossing—white clover (T. repens L.), rose clover (T. hirtum All.), crimson clover (T. incarnatum L.) and red clover (T. pratense L.)—and in one entry of the inbreeding subspecies of subterranean clover, T. subterraneum L. subsp. subterraneum (Katzn. and Morley). Resistance was not found in T. s. brachycalycinum (Katzn. and Morley) or T. s. yanninicum (Katzn. and Morley). In a greenhouse experiment, damage from BGA resulted in forage yield penalties of 72–100% when aphids were inoculated at 14 days after sowing and 13−74% when inoculated at 42 days after sowing, showing that in optimum conditions BGA can be a serious pest of clovers. Observations of severe damage caused by BGA in two regenerating field trials in southern New South Wales confirmed that field damage could occur in seasons favourable to aphid growth and reproduction. The severe damage that BGA can cause to clovers, and the sources of resistance we found, suggest that breeding for BGA resistance in clovers is warranted and feasible.
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Walkom, S. F., F. D. Brien, M. L. Hebart, and W. S. Pitchford. "The impact of selecting for increased ewe fat level on reproduction and its potential to reduce supplementary feeding in a commercial composite flock." Animal Production Science 56, no. 4 (2016): 698. http://dx.doi.org/10.1071/an14579.
Full textAbstract:
In southern Australian grazing systems, energy availability typically exceeds energy requirements. Grazing systems are likely to have higher profitability if ewes can utilise this relatively cheap feed by gaining more condition (muscle and fat) and then mobilising it when feed is expensive. The present paper focusses on the importance of genetic merit for fat on the lifetime productivity of the ewe within a commercial operation. The analysis was carried out on a maternal composite stud flock in Holbrook, New South Wales. Ultrasound fat and muscle depth were measured on 2796 ewes as lambs at post-weaning and as adult ewes, to determine the genetic relationship between young and adult body composition. The hypothesis of the paper is that selection for increased fat at young age will improve body condition of adult ewes, which will lead to improved reproduction and potentially reduced requirements for supplementary feeding. Given that the difference in feed cost between times of abundance and shortage is likely to be larger, the system may become more profitable despite being less efficient (owing to increased feed intake). Our results indicated that selection for scanned post-weaning fat and muscle depth in lambs should lead to increased fat muscle and body condition in the breeding ewe because of strong genetic correlation estimates between the post-weaning and adult traits of 0.68–0.99. The influence of body composition traits on reproduction (number of lambs weaned) within the stud flock was weak. However, it is hypothesised that by genetically increasing post-weaning fat depth in ewes, producers could improve profitability by reducing the demands for supplementary feeding.
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Stevens, Leonie, and Lynette Russell. "The Dutch East India Company (VOC) Tasman Map and Australia: Competing Interests, Myth Making, and an Australian Icon." Thematic Issue: The Social Lives of Maps, Volume 1 92-93 (August 10, 2022): 72–91. http://dx.doi.org/10.7202/1091245ar.
Full textAbstract:
The floor of the entrance to the Mitchell Library vestibule, which is part of the State Library of New South Wales, displays a stunning mosaic 1939-1941 reproduction of a seventeenth century map recording Abel Tasman’s two journeys of 1642 and 1644. It charts the west, north and southern coasts of the Australian continent, but is incomplete, thus representing the historical moment between an imagined Terra Australis Incognita, and the final survey of the east coast which presaged British colonisation. The original Tasman map, also held by the Mitchell library and currently undergoing restoration, has a strange and chequered biography. This paper explores the myths associated with what is known colloquially as the Bonaparte Tasman map, in honour of its last owner Prince Roland Bonaparte, a nephew of Napoleon. We examine its contested origins and role as an agent of Dutch East India Company imperial ambitions, relegation to forgotten cast-off when that empire collapsed, Bonaparte’s desire to gift it to the nascent Australian Commonwealth as a symbol of new nationhood, and the international subterfuge involved in its acquisition by not by the nation, but the State Library of NSW. Analysis of what was known of the map in the decades prior to its arrival in Australia challenges the conventional narratives, and we propose the biography of the Tasman map (and its embodiment in the Mitchell Library vestibule mosaic) is a study in imperialism, colonialism, federation, and power.
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Hennessy, DW, and PJ Williamson. "Effects of protein meal supplements on the growth and reproduction of Hereford heifers and cows grazing a native grass pasture in the subtropics." Australian Journal of Experimental Agriculture 28, no. 4 (1988): 439. http://dx.doi.org/10.1071/ea9880439.
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In the coastal subtropics of New South Wales, pasture growth occurs mainly in summer, when 500-600 mm of rain is expected. During winter, pasture quality declines, with digestible organic matter content as low as 374 g/kg DM in August and nitrogen down to 6.5 g/kg DM. Growth and reproduction of British breed cattle is also low so that, in an attempt to increase these attributes, protein meal supplements were offered to Hereford heifers and cows over 5 years. Heifers without supplements lost liveweight during their first winter and none calved after being mated at 15 months of age to Hereford bulls during a 9-week joining period. During their second winter, 58% of the heifers calved and, over 5 mating seasons, their mean annual calving rate was 48%. Supplemented heifers gained liveweight during their first winter and 95% of them calved, after first-joining at 15 months of age. Over 5 years their mean calving rate was 85%. Delaying first-joining to 27 months of age, as determined by a second group also supplemented with protein meal, did not increase production or mean calving rate (81%) over 5 years. The 230-day adjusted liveweight of calves weaned from non-supplemented heifers was 138 kg, significantly (P< 0.01) less than the 179 �10 kg (mean � s.e.d.) for calves weaned from the supplemented early-calving group, or 198 kg for the supplemented late-calving group. The results highlight the limitation to cattle production imposed by the low levels of nitrogen and poorly digestible pasture, and emphasise the important role of protein meal supplements with added minerals in increasing production of breeding herds grazing unimproved pastures in the subtropics.
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O'Brien, Eleanor K., Lucia A. Aguilar, David J. Ayre, and Robert J. Whelan. "Genetic tests of the isolation of rare coastal dwarf populations of Banksia spinulosa." Australian Journal of Botany 58, no. 8 (2010): 637. http://dx.doi.org/10.1071/bt10112.
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In southern New South Wales, a suite of widespread plant species exhibit short-statured ‘dwarf’ growth forms on coastal headlands. It is unclear whether such populations are genetically distinct or whether dwarfism is a plastic response to the environment. We used four microsatellite markers to assess genetic differentiation among populations from coastal and inland sites for Banksia spinulosa var. spinulosa. We sampled plants from six locations, including from three ‘dwarf’ and three ‘normal’ populations. Mean levels of genetic diversity were slightly higher in the forest (Na = 7.07 ± 0.25; He = 0.80 ± 0.09) than on the coast (Na = 5.92 ± 0.70; He = 0.72 ± 0.10). In general, populations displayed genotypic diversity expected for outcrossed sexual reproduction, with 161 of 172 individuals displaying unique genotypes and mean values of FIS close to zero. However, we found evidence of at least limited clonal replication in each of four populations and, within one coastal population, 11 of 27 individuals displayed one of three replicated genotypes, implying that the effective population size may be considerably smaller than would be inferred from the number of plants at this site. Relative to studies with other Proteaceae, this set of populations showed low, although significant, levels of differentiation (global FST = 0.061; P < 0.001), with extremely low, although significant, divergence of forest and coastal populations (FRT = 0.009; P < 0.001). There was no evidence of isolation by distance. These data imply that coastal dwarf populations are genetically similar to more extensive inland populations but in at least one case, may be at a greater risk of extinction because of low effective population size.
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Hinch, G. N., M. Lollback, S. Hatcher, J. Hoad, R. Marchant, D. F. Mackay, and J. M. Scott. "Effects of three whole-farmlet management systems on Merino ewe fat scores and reproduction." Animal Production Science 53, no. 8 (2013): 740. http://dx.doi.org/10.1071/an12440.
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As part of the Cicerone Project’s whole-farmlet experiment on the Northern Tablelands of New South Wales, Australia, the fat scores and reproductive performance of ewes were measured to assess the effect of different management systems on these important production parameters over time. The three farmlets (each of 53 ha) included one (farmlet B) subjected to ‘typical’ district management consisting of moderate levels of inputs and a target stocking rate of 7.5 dse/ha, with flexible grazing management across eight paddocks. A second farmlet (A) was managed in a similar fashion to farmlet B with respect to number of paddocks and grazing management, but modified by high rates of pasture renovation and higher levels of soil fertility, with a target stocking rate of 15 dse/ha. The third farmlet (C) was managed at the same level of moderate inputs as farmlet B but employed intensive rotational grazing over 37 paddocks and also had a high target stocking rate of 15 dse/ha. The experiment was conducted over 6.5 years from July 2000 to December 2006. In spite of the fact that target levels of stocking rate were chosen at the beginning of the experiment, stocking rate, together with fat scores and reproduction were treated as emergent properties of each farmlet system. Joining took place in April–May and lambing occurred in September–October of each year. Over the first 2 years of the experiment, there were few differences among farmlets in ewe fat scores or reproductive performance. From 2003 onwards, while the percentage of ewes pregnant was similar between farmlets, the average proportion of multiple births (ewes scanned in late July, with twins) was 30%, 16% and 12%, respectively, on farmlets A–C. However, lamb losses were greater on farmlet A, with average lamb mortalities recorded on farmlets A–C of 29%, 10% and 19%, respectively. Over the duration of the experiment, ewes on farmlets A and B were more often above a fat score level of 3, and less often below 2.5, than were ewes from farmlet C. Differences among farmlet ewes in fat score were found to be significant in 7 of the total of 13 assessments over the duration of the experiment. A generalised additive model applied to whole-farmlet data showed that green digestible herbage, legume herbage, stocking rate, the amount of supplement fed and especially the proportion of each farmlet grazed at any one time all influenced fat scores of ewes. While fat scores and conception rates tended to be highest on farmlet A, farmlet B had slightly better reproductive outcomes due to less lambing losses, whereas ewes on farmlet C tended to have somewhat lower fat scores and levels of reproduction. These farmlet-scale findings highlighted the importance for livestock managers to focus not only on grazing management, stocking rate and stock density during lambing, but also on the availability of sufficient green, and especially legume herbage, and the difficulty of overcoming a deficit in quality herbage with supplementation.
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Otieno, Beryn, Helen Nahrung, and Martin Steinbauer. "Where Did You Come From? Where Did You Go? Investigating the Origin of Invasive Leptocybe Species Using Distribution Modelling." Forests 10, no. 2 (February 1, 2019): 115. http://dx.doi.org/10.3390/f10020115.
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Research Highlights: We present the first attempts to model the distributions of the two cryptic and globally invasive species of Leptocybe invasa sensu lato (Fisher & LaSalle) (Hymenoptera: Eulophidae) in its purported country of origin, namely Australia. Background and Objectives: Leptocybe invasa is an invasive eucalypt-galling wasp that spread quickly all over the world in the early to mid-2000’s, achieving significant pest status through its severe impacts on the growth and productivity of extra-limital eucalypt plantations. Until its discovery in Europe and the Middle East, the genus was undescribed, and its native range remains unclear. Molecular studies indicate the globally invasive population comprises two cryptic species with variable modes of reproduction. Collection records from Australia, the purported origin, represent only one of the invasive lineages, restricted to subtropical and tropical Queensland and northern New South Wales. To date, the original invasive lineage has not been found in Australia, despite searches over the seventeen years that it has been spreading overseas. Materials and Methods: To understand the distributions of the invasive populations, and to infer Leptocybe spp. native ranges within Australia, we used correlative niche modelling in Maximum Entropy (MaxEnt) and multivariate analysis, and created a CLIMEX model based on development rates of an invasive population. Results: We used the environmental conditions in the extra-limital range to infer possible origins, with our findings supporting the possibility that the invasive populations may have originated from different populations in Australia. Conclusions: We highlight the need for better understanding of the distribution, genetic diversity, and reproductive mode of the species within Australia. The variety of climatic niches occupied by invasive lineages of the wasp potentially present new threats to eucalypts in previously uninfested habitats.
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Denham, Andrew J., and Robert J. Whelan. "Reproductive ecology and breeding system of Lomatia silaifolia (Proteaceae) following a fire." Australian Journal of Botany 48, no. 2 (2000): 261. http://dx.doi.org/10.1071/bt98039.
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Lomatia silaifolia (Smith) R.Br. (Proteaceae) is a common shrub in southeastern Australian bushland that generally flowers only once after each fire. However, little is known of the details of this post-fire flowering. Lomatia silaifolia has flowers well-spaced along its conflorescence axis, unlike many other Proteaceae species, thus allowing close examination of the influence of flower position, mate choice and flowering sequence on fruit production. We examined breeding system, flowering phenology and spatial patterns of fruit set in the species, after a fire in September 1992 at Bulli Tops, New South Wales. Flowering occurred in December–January, but only in the first and second summers after the fire. The species is partially self-compatible: only 25% of self-pollinated conflorescences initiated fruits compared with 100% of cross-pollinated conflorescences. Fewer flowers initiated fruits after hand self-pollination (3.0%) than after cross-pollination (35.4%). Self-pollinated flowers produced fewer viable seeds (22.2% viable) than cross-pollinated flowers (62.9% viable). Pollen tubes were found in 72% of the self-pollinated flowers examined, suggesting that there is no early stylar self-incompatibility in the species. There was a high level of herbivory on flowering and fruiting branches, with 69% of unbagged branches completely destroyed. This may significantly affect recruitment in the species, given the limited opportunities for reproduction in the post-fire environment. In this study, fruits were evenly distributed along the conflorescence axis unlike some other species in the Proteaceae with more compressed, spike-like flowering structures where fruits are typically concentrated in some parts of the conflorescence axis (e.g. Telopea and some Banksia spp.). No bird visitors to flowers were observed, but a variety of insect visitors were identified.
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Bradley, F. H., R. N. Oram, and K. W. Malafant. "Inheritance of partial resistance to the brown spot disease in Lupinus angustifolius L." Australian Journal of Agricultural Research 53, no. 8 (2002): 919. http://dx.doi.org/10.1071/ar01155.
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Brown spot (BS) is a damaging disease of narrow-leafed lupins (Lupinus angustifolius L.), particularly in Western Australia. Breeding for resistance to the causal agent [Pleiochaeta setosa (Kirchn.) Hughes] has had some success. Here, earlier data on the extent and inheritance of resistance to BS are presented as a possible guide for future breeding programs. In 1980, 236 Mediterranean wild accessions from the Australian germplasm collection, and 17 cultivars and 20 breeding lines of L. angustifolius and L. albus L., were tested by natural infection in replicated short rows at 2 sites in southern New South Wales. The area of lower leaves covered by lesions was up to 70% lower on partially resistant lines than on commercial cultivars. Twelve wild accessions were consistently more resistant than 5 cultivars at Wagga Wagga in 1980 and in 2 subsequent years, in which 66 wild lines and 6 cultivars were tested. However, the rankings at Wagga Wagga differed from those in coastal Western Australia, suggesting that spatial differences occur in the pathotype composition of the fungus. The absence of sexual reproduction in the fungus suggests that its pathotype spectrum would change only slowly at each location. Unimodal distributions of BS scores for individual plants were found in the F2 of Illyarrie (susceptible) � CPI 67877 (resistant) and in the backcross to Illyarrie. The F2 mean was intermediate between the 2 parental means, and only a few plants had a score as low as the resistant parent. The regression of the mean scores for 15 F2 families from crosses among 7 wild lines, and between these and 2 susceptible cultivars, on the respective mid-parent values gave a narrow-sense heritability estimate of 0.94 ± 0.17 on a family mean basis. Thus, resistance was controlled by many loci with co-dominant alleles and should be robust. There was no linkage of resistance genes to the low alkaloid or white flower/green plant loci. Assuming the absence of dominance, the upper limit of narrow-sense heritability on a single plant basis was 0.50 ± 0.13. Several rounds of selection of partially resistant individuals in F2 families and intercrossing among F3 plants from many different wild � domesticated crosses are likely to produce cultivars with much more resistance than those now available. The applicability of the results at Wagga Wagga to the eastern wheatbelt of Western Australia, where BS is acute, and optimum field selection procedures are discussed.
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Fulkerson, W. J., J. Wilkins, R. C. Dobos, G. M. Hough, M. E. Goddard, and T. Davison. "Reproductive performance in Holstein-Friesian cows in relation to genetic merit and level of feeding when grazing pasture." Animal Science 73, no. 3 (December 2001): 397–406. http://dx.doi.org/10.1017/s1357729800058367.
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AbstractOne hundred and eight Holstein-Friesian cows in six herds were run on six separate farmlets over a 5-year period from 1995 to 1999 at Wollongbar Agricultural Institute, on the subtropical north coast of New South Wales, Australia. Three of the herds comprised high genetic merit (HGM) cows — Australian breeding value (ABV) of +49·1 kg for milk fat (F) plus protein (Pr) and three herds comprised low genetic merit (LGM) cows-ABV of 2·3 kg. Within genetic merit groupings, one herd was given 0·34 t (l), one herd was given 0·84 t (m) and one herd 1·71 t (h), of concentrate per cow per lactation. Within each genetic merit group, cows were matched for milk yield and live weight, and over all groups for time of calving and age at the commencement of the study. The 30 paddocks within each farmlet were matched between farmlets for pasture type and pasture growth rate and soil fertility. Half the cows within each herd calved over a 3-month period in spring and the other half in autumn. Strict management criteria ensured that there was no bias towards particular treatment groups.HGM cows were ‘open’ (days from calving to conception) for 8 days longer than the LGM cows (99 v. 91 days). The lHGM cows took 11 days longer to commence luteal phase activity and 21 days longer to first observed oestrus post calving than hLGM cows (P < 0·001), with the other groups being intermediate.After 24 days of mating, 22% of lHGM cows were pregnant, and this was less than half of the rate of the best herd-mLGM. After 9 weeks of mating, the chances of an LGM cow being pregnant was 87% greater than an HGM cow. After 12 weeks of mating, 70% of lHGM cows were pregnant compared with a mean pregnancy rate of 87% for the LGM cows.The number of cows treated for abnormal ovarian activity (anoestrus, cystic) was highest (P < 0·001) in the HGM herds given ‘l’ and ‘m’ levels of concentrate compared with the remaining herds (0·24 v. 0·12 treatments per cow mated, respectively).There was a significant positive relationship between live-weight change from 4 weeks before, to the start of, the mating period and the chances of a cow being pregnant at 24 days (P < 0·05) and at 6 and 9 weeks after the commencement of mating.There was a significant negative relationship (P < 0·001) between the change in daily F plus Pr yield, from the start to 4 weeks after mating began, and pregnancy rate at 9 weeks. The change in F plus Pr yield was +63 g/day for cows pregnant at nine weeks as opposed to +154 g/day for cows not pregnant.The results of the present study indicate that the reproductive performance of HGM cows, with a mean of 61% North American (NA) genes, is lower than LGM cows (22% NA genes) under a predominantly pasture-based system of farming. The influence on reproduction was possibly due to genes favouring partitioning of energy to milk yield rather than body-condition maintenance in the HGM cows and when food intake was inadequate, then being more willing to use body reserves.These reproductive problems may be reduced by more intensive reproductive management. However, such practices are costly and time consuming. Another approach may be to ensure that live-weight loss over the mating period is minimized by strategic supplementary feeding.
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Law, Yin Jun, Ning Zhang, Christos A. Venetis, Georgina M. Chambers, and Katie Harris. "The number of oocytes associated with maximum cumulative live birth rates per aspiration depends on female age: a population study of 221 221 treatment cycles." Human Reproduction 34, no. 9 (August 9, 2019): 1778–87. http://dx.doi.org/10.1093/humrep/dez100.
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Abstract STUDY QUESTION What is the number of oocytes where the maximum cumulative live birth rate per aspiration (CLBR) is observed during ART in women of different ages? SUMMARY ANSWER The maximum CLBR was observed when around 25 oocytes were retrieved in women between 18–35 years of age, around 9 oocytes in women more than 45 years of age and continued to increase beyond 30 oocytes in women between 36–44 years of age. WHAT IS KNOWN ALREADY The live birth rate per fresh or frozen/thaw embryo transfer (FET) procedure has traditionally been the main measure of ART success. However, with the introduction of highly efficient embryo cryopreservation methods, CLBR encompassing live delivery outcomes from the fresh and all subsequent FET following a single ovarian stimulation and oocyte collection is increasingly viewed as a more meaningful measure of treatment success. There is evidence suggesting that larger oocyte yields are associated with increased likelihood of cumulative live birth per aspiration. Whether this association is the same across female ages has not yet been properly investigated. STUDY DESIGN, SIZE, DURATION This is a large retrospective population-based cohort study using data from the Australian and New Zealand Assisted Reproduction Database (ANZARD). ANZARD contains information from all ART treatment cycles carried out in all fertility centres in Australia and New Zealand. Overall, 221 221 autologous oocyte aspiration cycles carried out between January 2009 to December 2015 were included in the analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS Cumulative live birth per aspiration was defined as at least one liveborn baby at ≥20 weeks gestation resulting from an ART aspiration cycle, including all fresh and FET resulting from the associated ovarian stimulation, until one live birth occurred or all embryos were used. Cycles where no oocytes were retrieved were excluded from analysis as there is no possibility of live birth. Analyses of data were performed using generalized estimating equations to account for the clustered nature of data (multiple cycles undertaken by a woman). Univariate and multivariable regression analysis was performed to identify and adjust for factors known to independently affect cumulative live birth per aspiration. An interaction term between female age and the number of oocytes retrieved was included to assess whether the age of the women was associated with a different optimal number of oocytes to achieve at least one live birth from an aspiration cycle (i.e. the effect-modifying role of female age). The likelihood of cumulative live birth per aspiration was calculated as odds ratios (ORs) with 95% CI. MAIN RESULTS AND THE ROLE OF CHANCE The median number of oocytes retrieved was 7 (interquartile range, 4–12) and median age of patients was 36 (interquartile range, 33–40). The overall CLBR was 32.2%. The results from the multivariable regression analysis showed that the number of oocytes retrieved remained a significant predictor (P < 0.001) of cumulative live birth per aspiration after adjusting for female age, parity and cycle count. Compared to the reference group of 10–14 oocytes retrieved, the adjusted odds for cumulative live birth per aspiration increased with the number of oocytes retrieved: 1–3 oocytes, 0.21 (95% CI, 0.20–0.22); 4–9 oocytes, 0.56 (95% CI, 0.55–0.58); 15–19 oocytes, 1.38 (95% CI, 1.34–1.43); 20–24 oocytes, 1.75 (95% CI, 1.67–1.84); and 2.10 (95% CI, 1.96–2.25) with more than 25 oocytes. After stratifying by female age group, the rate of increase in CLBR per additional oocyte retrieved was lower in the older age groups, indicating that higher oocyte yields were more beneficial in younger women. CLBR of patients in the <30 years and 30–34 years age groups appeared to reach a plateau (with only minimal increase in CLBR per additional oocyte retrieved) after retrieval of 25 oocytes at 73% and 72%, respectively, while CLBR of patients in the 35–39 years and 40–44 years age groups continued to increase with higher oocyte yields, reaching 68% and 40%, respectively, when 30 or more oocytes were retrieved. CLBR of patients aged 45 years and above remained consistently below 5%. Findings suggest that the number of oocytes retrieved where CLBR appears to be maximized is around 25 in women between 18–35 years, more than 30 in women between 36–44 years and around 9 in women 45 years and older. However, results for women aged 45 years and older may not be as robust due to the relatively small sample size available in this age group. LIMITATIONS, REASONS FOR CAUTION As with all large retrospective database studies, there are potential confounders that cannot be accounted for. Despite the current study being based on complete ascertainment of ART cycles across two countries, ovarian stimulation protocols, oocyte quality parameters and a number of important patient characteristics are not collected by ANZARD. Additionally, a small number of cycles were available for women over 45 years yielding more than 15 oocytes, making these estimates unreliable. WIDER IMPLICATIONS OF THE FINDINGS The results from this study demonstrate that the number of oocytes retrieved where the maximum CLBR is observed during ART is dependent on female age. This provides information for clinicians and patients to understand the modifying effect of age on the number of oocytes retrieved and the likelihood of success with ART. STUDY FUNDING/COMPETING INTEREST(S) No external funding was used for this study. The Fertility Society of Australia funds the National Perinatal Epidemiology and Statistics Unit to manage ANZARD and conduct national reporting of ART in Australia and New Zealand. Associate Professor Georgina Chambers (G.C.) is employed by the University of New South Wales (UNSW) and is director of the National Perinatal Epidemiology and Statistics Unit at UNSW. G.C. was also a paid member of the Australian governments Medicare Benefits Scheme taskforce on assisted reproductive technologies in 2017.