Academic literature on the topic 'Black rhinoceros Breeding New South Wales'

AbstractColour change is a well-known phenomenon in many amphibians. Most of these changes involve transient darkening, lightening, or attainment of breeding colours. Nuptial calosities may become lighter outside the main breeding season. Depigmentation as an extreme form of lightening has been documented also for keratinized structures of tadpole mouths. Here I report a hitherto overlooked type of colour change: darkening of metatarsal tubercles from white to almost black. At Kinchega National Park in New South Wales, individuals of the Australian borrowing frog Neobatrachus pictus emerging from their aestivation burrows after rains had white outer metatarsal tubercles. Within a few hours to two days the metatarsal tubercles had turned completely black. This indicates that the extent of black colouration of the outer metatarsal tubercle hitherto used to discriminate the species N. centralis from N. pictus and N. sudelli is unreliable.

The Parma Wallaby Macropus parma, native only to Australia, exemplifies a number of issues currently under discussion regarding the conservation of Australian marsupials. Thought to be extinct in the earlier part of this century, an expatriate population was identified on Kawau Island, New Zealand in 1967. These animals were used to supply zoos and captive breeding colonies throughout the world. Subsequently, parma populations were rediscovered in the Great Dividing Range of New South Wales, Australia. The Australian populations are small and inhabit severely restricted localities where they are highly vulnerable to predation and further habitat loss. Strategies for the preservation of parmas in Australia include the reintroduction of parmas either directly from Kawau Island or from established captive colonies. However, the founder number of Parma Wallabies on Kawau Island is unknown, hence it is possible the New Zealand derived parmas have a restricted genetic base compromising their suitability for reintroduction programmes. Additionally, there is a possibility that introgression has occurred between parmas and Black-striped Wallabies Macropus dorsalis on the island. Here we report that the level of genetic variation in New Zealand derived Parma Wallabies is not markedly reduced, and that no detectable introgression has taken place between Parma and Black-striped Wallabies. Indeed, re-examination of records casts doubt upon the suggestion that Black-stripes were introduced to Kawau Island.

The present paper addresses turning knowledge into practical benefit; acknowledging a critical emphasis of the career of John L. Black. Average efficiency of pasture use by beef enterprises in southern Australia is historically ~35%. Two projects established in 2002 showed that the efficiency of pasture use could approach 90% and the conservative rates observed were due to a low adoption of existing knowledge and the perceived risks from intensification. A risk-control management system, ‘More Beef from Pastures’, was developed from these projects, to identify management practices that had the largest impacts on productivity and profitability, the variables that needed to be measured and the upper and lower limits for those measurements to optimise enterprise performance. The principles from that system were incorporated into a productivity and economic spreadsheet model for a beef enterprise near Blayney on the Central Tablelands of New South Wales. The present paper reports the effects on productivity and profitability of several management scenarios, including current practice with 180 breeding cows and progeny sold in the second year after birth; buying and selling steers; making silage; or combinations of steers and silage, to maintain pasture availability between 1200 and 2600 kg DM/ha. Simulations were conducted for rainfall and growth of a phalaris–subterranean clover pasture predicted for the Blayney climate by the Sustainable Grazing Systems model for the Years 2000–2011. The simulations covered eight consecutive years from 2002 to 2009, when mean pasture growth was only 70% of the average. Results from the simulations for current practice were similar to those observed for the enterprise. The simulations showed the importance on profitability of utilising excess pasture in years of high pasture growth. The highest average profitability across years resulted from the scenario involving purchase and sale of steers, but year-to-year fluctuations were large and significant capital was required. The silage and steer-silage scenarios were intermediate in profitability, and depended on initial silage reserves and numbers of breeding cows. The exercise demonstrated that a simple spreadsheet model based on principles of animal nutrition, pasture management and economics was needed to fully evaluate alternative management strategies for practical benefit on existing beef enterprises.

The present experiment, ‘Regional Combinations’, examined growth, and carcass- and meat-quality traits in the progeny of sires genetically diverse for fatness and meat yield when grown at different rates from weaning to feedlot entry. The present paper is the first of several papers describing results from the New South Wales site, one of four in the project. It reports the effects on growth and body composition of steers during backgrounding and feedlot finishing phases. A total of 43 sires within three carcass-class categories, defined as high potential for meat yield, for marbling or for both traits, was used, based on estimated breeding values for retail beef yield and intramuscular fat. Sires were drawn from Angus, Charolais, Limousin, Black Wagyu and Red Wagyu breeds, providing a range of carcass sire types across the three carcass classes. Matings were by artificial insemination to Hereford dams from a single herd. Steer progeny were grown at conventional (slow: ~0.5 kg/day) or accelerated (fast: ~0.7 kg/day) rates from weaning to feedlot entry weight, targeting group means of 400 kg. Accelerated and conventionally grown groups from successive calvings entered the feedlot at similar entry liveweights at the same time, then having identical management during the 100-day finishing phase before slaughter. Within finishing cohorts, fast backgrounding growth resulted in increased subcutaneous fatness at feedlot entry in steers of all carcass types. Slow growth during backgrounding resulted in faster (compensatory) growth in the feedlot in all classes and sire types. This increased the deposition of fat in slow-backgrounded steers compared with that in fast-backgrounded steers during feedlotting, and thus reduced the difference between the groups in P8 and rib fat at feedlot exit. However, there did appear to be an advantage in the level of compensation in the feedlot in favour of those sire types with a genetic propensity for faster growth. Backgrounding growth rate affected body composition and the rate of weight gain during finishing. Faster growth produced more subcutaneous fat during both backgrounding and finishing. Steer progeny groups clearly showed the expected responses in growth and body composition, on the basis of the genetic potential of their sires.

Canola (Brassica napus L.) is a significant oilseed break crop in Western Australia. In late October 2012, canola plants (cv. Jackpot) showing typical symptoms of stem rot with bleached appearance and fluffy white fungal growth on the infected tissues were observed in an experimental plot at Katanning, Western Australia. Severely affected plants were lodged with partially filled pods and shriveled seeds. Small, irregular sclerotia (<2 mm) were found inside the plants and were more concentrated in the root and basal stem than in the upper stem regions. Ten sclerotia from three symptomatic plants were surface sterilized with 1.25% NaOCl for 1 minute, rinsed twice in sterile distilled water and plated on potato dextrose agar (PDA) supplemented with 10 mg liter–1 Aureomycin. Plates were incubated under a black light at 22 ± 2°C. Sclerotinia minor Jagger was consistently isolated as identified by colony morphology, abundant sclerotia on PDA, and size of sclerotia <2 mm (3). A pathogenicity test was conducted on six 7-week-old canola plants cv. Tawriffic. Mycelial plugs (5 mm diameter) were excised from the margins of actively growing 3-day-old cultures and attached on to the 2nd and the 4th internodes of the main stem with Parafilm. Three plants inoculated with agar plugs without mycelium served as controls. Following inoculation, the plants were kept in a misting chamber for 48 h and then transferred to a growth room at 18 ± 2°C with a 12-h photoperiod. Typical lesions of stem rot similar to those observed in the field were noticed 3 days after inoculation. Within a week, all the inoculated plants were completely girdled by the lesions with stems breaking off and collapsing at the point of inoculation. Small sclerotia formed within lesions on the outside of the diseased stems. S. minor was reisolated from the stems of symptomatic plants, fulfilling Koch's postulates. No symptoms developed on the control plants. S. minor has previously been reported on host plants other than canola in Western Australia (4), canola petals in New South Wales, Australia (2), and also on canola stems in Argentina (1). To our knowledge, this is the first report of occurrence of S. minor on canola in Western Australia. Although S. sclerotiorum is the predominant species causing stem rot in canola in Western Australia, S. minor has the potential to cause significant yield losses under favorable environmental conditions. Correct identification and monitoring a shift in pathogens is essential for implementing effective management strategies and breeding resistant varieties. References: (1) S. A. Gaetán et al. Plant Dis. 92:172, 2008. (2) T. Hind-Lanoiselet et al. Aust Plant Pathol. 30:289, 2001. (3) L. M. Kohn. Phytopathology 69:881, 1979. (4) R. Shivas. J. Royal. Soc. Western Australia 72:1, 1989.

Selected Papers from the Rhinoceros Conservation Workshop, Skukuza, Kruger National Park,31 August – 4 September 1988 The conservation plan for the black rhinoceros presents specific aims and management guidelines for the conservation of the African black rhinoceros Diceros bicomis in the Republic of South Africa, the TBVC states and Namibia. The adoption of this plan, and the application of the strategies described therein (managing existing populations, establishing new populations and aspects of captive breeding) by the relevant conservation authorities should enhance the survival prospects of this species, both in the region and globally.