http://espace.library.uq.edu.au/ The University of Queensland en Fez http://blogs.law.harvard.edu/tech/rss http://espace.library.uq.edu.au/view/UQ:231561 2011-03-07T00:00:00Z Turni, C. og Blackall, P. J. http://espace.library.uq.edu.au/view/UQ:231747 2011-03-07T00:00:00Z Desmarchelier, P. og Lew, A. og Caique, W. og Knight, S. og Toodayan, W. og Isa, A. R. og Barnes, A. http://espace.library.uq.edu.au/view/UQ:231687 2011-03-07T00:00:00Z Fordyce, G. og Cooper, N. J. http://espace.library.uq.edu.au/view/UQ:231714 Gooseberry vein banding disease (GVBD) affects Ribes species and cultivars worldwide. It is the second most important virus-like disease in these crops after black currant reversion disease. In this paper, we describe a bacilliform virus, Gooseberry vein banding associated virus (GVBAV), which is associated closely with GVBD, and provide evidence that GVBAV is a distinct species within the genus Badnavirus. Purified GVBAV particles were ca. 120 × 30 nm in size and contained dsDNA. The sequence of a 1.5-kb DNA fragment amplified from viral genomic DNA was similar to those of a wide range of badnaviruses and contained motifs characteristic of the RNase H domain of the badnavirus open reading frame (ORF) III polyprotein. Phylogenetic analyses suggest that GVBAV is most closely related to Spiraea yellow leaf spot virus. Using sequence derived from the polymerase chain reaction (PCR)-amplified DNA fragment, virus-specific primers were designed. These primers were used in PCR to assay for GVBAV in a range of Ribes germplasm affected with GVBD, with other unrelated virus-like diseases and viruses found in Ribes, and in healthy plants. GVBAV was detected in all of 58 GVBD-affected plants from diverse sources, but not from healthy Ribes plants nor from plants infected with other viruses. 2011-03-07T00:00:00Z Jones, A. T. og McGavin, W. J. og Geering, A. D. W. og Lockhart, B. E. L. http://espace.library.uq.edu.au/view/UQ:245217 Because of their role in causing schistosomiasis, flukes of the genus Schistosoma are the best known of all digeneans. The genus has traditionally been divided into four familiar species groups. Here we report on three poorly known species of Schistosoma, one of which, Schistosoma hippopotami, is known from the hippopotamus, one of which is provisionally identified as Schistosoma edwardiense, another hippo parasite, and a third that has not previously been described. All were collected from freshwater snails obtained from Lake Edward, western Uganda, the type locality for both known hippo schistosomes. The three different kinds of schistosome cercariae differ from one another in size, and all are readily differentiated by their long tail stems from the cercariae of human-infecting species. Furthermore, each was recovered from a different genus of snail host, Biomphalaria sudanica, Bulinus truncatus or Ceratophallus natalensis. Molecular analysis, based on 8350 bases of combined nuclear and mitochondrial DNA, groups these three long tail-stem cercariae into a well supported clade that does not associate with any of the recognised species groups. The placement of this clade, basal to all African species plus several Asian species, suggests that there has been an ancient association between Schistosoma and hippos. This new African Schistosoma clade advocates the need for further modification of the traditional species group-based classification. Two of the four species groups are paraphyletic. It also suggests that Schistosoma has been remarkably plastic with respect to adapting to snail hosts - three distantly related genera of planorbid snails have been exploited by worms within a single clade. Finally, it adds a new layer of complexity to deciphering the origins of Schistosoma, often considered to be African but recently challenged as being Asian. In the late Cenozoic the distribution of hippo species straddled both Africa and Asia and they may have provided a means for the introduction of blood flukes to Africa. 2011-08-10T00:00:00Z Morgan, Jess A. T. og DeJong, Randall J. og Kazibwe, Francis og Mkoji, Gerald M. og Loker, Eric S. http://espace.library.uq.edu.au/view/UQ:266623 2012-02-02T00:00:00Z Fordyce, G. og Allingham, A. og Candy, B. og Bettridge, S. og Lynch, E. og Bertram, J. http://espace.library.uq.edu.au/view/UQ:231442 The animal welfare issues faced by the northern Australian beef cattle industry are similar to those faced by extensive livestock production industries in other countries. However, northern Australia is characterised by climatic extremes and large areas/distances and these factors, together with low management inputs, mean that the industry faces significant challenges to assure high standards of animal welfare. In this review, the following issues are discussed: behavioural restriction; ‘natural disasters’; nutrition; health; a number of aspects relating to human–animal interactions, particularly mustering (gathering/rounding up) andmovingcattle,andtheconsequences for welfareof the timingandfrequency of handling; ‘surgical’ procedures; identification; transportation, including live export; and predation. The use of cattle adapted to the northern Australian environment alleviates many potential welfare problems. In addition, significant improvements to animal welfare could be made very quickly with a few straightforward management changes, such as improved planning for extended dry periods and drought; wider use of conservative stocking rates and supplementary feeding; broader implementation of vaccination programs; and greater implementation of weaner training programs. Further, a dramatic improvement for very large numbers of cattle could be made through the selection and use of polled genotypes to eliminate horned cattle. Research from Europe suggests that current Australian recommendations for the duration of land transportation journeys may be excessive and could compromise welfare, but further research under northern Australian conditions is required. Research and development is also needed in non-invasive alternatives to castration and spaying, but in the meantime the welfare of males could be improved by castrating earlier in the animals’ lives. However, it is acknowledged that this would require major changes to current cattle management practices. 2011-03-07T00:00:00Z Petherick, J. Carol http://espace.library.uq.edu.au/view/UQ:231443 The land-based livestock industries in Australia face particular challenges in assuring high animal welfare standards due to large land areas and stock numbers, climatic extremes and relatively low inputs in terms of manpower and infrastructure. These factors make a major contribution to welfare issues associated with nutrition, health, mustering and handling, and transportation. In addition, welfare is seriously compromised by the invasive procedures that are conducted on livestock, such as castration, dehorning, mulesing and tail-docking. At least partial solutions to welfare issues associated with nutrition, health, mustering and handling are available now and should be universally adopted. There are potential solutions available for castration and dehorning, which require some further research and development. Genetic technologies can also provide a solution for dehorning, mulesing and tail-docking. Inevitably, all livestock experience transportation, and research and development is required to determine optimal practices for Australian conditions in order to minimise the negative impacts on animal welfare. 2011-03-07T00:00:00Z Petherick, J. C. http://espace.library.uq.edu.au/view/UQ:228535 2011-02-09T00:00:00Z Harris, Philip J. og Henry, Robert J. og Blakeney, Anthony B. og Stone, Bruce A. http://espace.library.uq.edu.au/view/UQ:234595 2011-03-10T00:00:00Z Samosir, Y. M. S. og Godwin, I. D. og Adkins, S. W. http://espace.library.uq.edu.au/view/UQ:250734 2011-09-11T00:00:00Z Sultanbawa, Y. og Cusack, A. og Currie, M. og Davis, C. http://espace.library.uq.edu.au/view/UQ:231917 A novel nuclear magnetic resonance (NMR) assay has been developed to monitor lipase-catalyzed esterification reactions without the need to extract and purify the individual components. The technique measures ratios of ester:alcohol signals and has been shown to be both efficient and reproducible. The assay has proven useful as a quick screen for the effect of varying conditions on the extent of esterification in various biphasic solvent systems and can be applied to both saturated and unsaturated long-chain fatty acid and alcohol substrates. The NMR ratio technique has been used to quantitate the extent of reaction in the Candida cylindracea lipase-catalyzed synthesis of oleyl palmitate, stearyl palmitate, oleyl oleate, oleyl gamma-linolenate and oleyl linoleate. The identity of these products was confirmed by high-resolution mass spectrometry. 2011-03-07T00:00:00Z O'Connor, C. J. og Petricevic, S. F. og Coddington, J. M. og Stanley, R. A. http://espace.library.uq.edu.au/view/UQ:232751 2011-03-07T00:00:00Z Cordeiro, Giovanni og Eliott, Frances G. og Henry, Robert J. http://espace.library.uq.edu.au/view/UQ:258308 2011-10-21T00:00:00Z Henry, R. J. http://espace.library.uq.edu.au/view/UQ:231540 2011-03-07T00:00:00Z Miflin, Jeanette K. og Templeton, Jillian M. og Blackall, P. J. http://espace.library.uq.edu.au/view/UQ:266786 2012-02-03T00:00:00Z Brossier, Morgan og Cusack, Andrew og Edwards, David og Kelly, Michael og Sultanbawa, Yasmina http://espace.library.uq.edu.au/view/UQ:231950 2011-03-07T00:00:00Z Zhang, J.L. og Melton, L.D. og Stanley, R. http://espace.library.uq.edu.au/view/UQ:292620 Glucosinolates are a group of sulphur-containing glycosides found in the plant order Brassicales which includes the Brassica vegetables such as broccoli, cabbage and cauliflower. When brought into contact with the plant enzymes, myrosinases, the glucosinolates break down releasing glucose and other products which serve principally in plant defence against herbivores. The most important of the products from a human nutritional viewpoint, are the isothiocyanates. These potent inducers of detoxifying enzymes bestow the distinct anti-cancer properties on these plants. Unique among tropical fruits, papaya is known to contain an abundance of one particular glucosinolate, glucotropaeolin. Other compounds that play a pivotal role in the chemical defence system of many plants are the cyanogenic glycosides. Cyanogenic glycosides are activated by plant enzymes in the event of pest attack, releasing the deterrent: toxic hydrogen cyanide. Papaya, in addition to glucosinolates, also contains low levels of cyanogenic glycosides, an unusual occurrence because it was assumed that the two classes of metabolites were mutually exclusive. Studies measuring the levels of both in the edible parts of the papaya fruit and other utilised tissues are discussed and considered in the context of potential human health ramifications. 2013-03-03T00:53:05Z Williams, David J. og Pun, Sharon og Chaliha, Mridusmita og Scheelings, Pieter og O'Hare, Timothy http://espace.library.uq.edu.au/view/UQ:232026 2011-03-07T00:00:00Z Meinke, H. og Hammer, G. L. http://espace.library.uq.edu.au/view/UQ:231997 2011-03-07T00:00:00Z Hammer, Graeme L. og Sinclair, Thomas R. og Boote, Kenneth J. og Wright, Graeme C. og Meinke, Holger og Bell, Mike J. http://espace.library.uq.edu.au/view/UQ:228491 2011-02-09T00:00:00Z Bradbury, Louis M. T. og Henry, Robert J. og Jin, Qingsheng og Reinke, Russell F. og Waters, Daniel L. E. http://espace.library.uq.edu.au/view/UQ:245219 The Planorbidae represent one of the most important families of freshwater snails. They have a wide distribution and are significant both medically and economically as intermediate hosts for trematode worms. Digenetic trematodes of the genus Schistosoma cause schistosomiasis, a disease that infects 200 million people, and domestic animals throughout the tropics. Three of the four recognized species groups of Schistosoma rely on snails of the family Planorbidae to complete their life cycles. Each species group requires a specific planorbid genus - Bulinus, Biomphalaria, or Indoplanorbis. Our understanding of the relationships among the genera within the Planorbidae is rudimentary and based solely on internal anatomy and shell morphology. Two molecular markers, ribosomal 28S and actin exon 2, were sequenced and a phylogeny constructed for 38 taxa representing 16 planorbid genera. The phylogeny supports the division of the Planorbidae into two subfamilies, the Bulininae and Planorbinae. Interestingly, two representatives of the family Ancylidae fall within the Planorbidae highlighting the need for further analysis and possible reclassification of this group. A molecular based phylogeny of the genus Schistosoma was then mapped against the snail tree. The trees indicate that planorbid-transmitted Schistosoma appear not to be co-speciating with their current snail host lineages. Rather, host switching was prominent, including a switch involving two distantly related planorbid genera, Biomphalaria and Bulinus. Our study of the Planorbidae poses fundamental questions regarding how and when Schistosoma acquired new snail hosts, including how switches to relatively distant hosts are accomplished and why some available planorbids were not colonized. 2011-08-10T00:00:00Z Morgan, J. A. T. og DeJong, R. J. og Jung, Y. H. og Khallaayoune, K. og Kock, S. og Mkoji, G. M. og Loker, E. S. http://espace.library.uq.edu.au/view/UQ:231905 Drying behavior at 60°C was studied in uniform rings of apple fruit parenchyma after vacuum infiltration of fluids with different osmolality and surface tension. All infiltrations gave a halved final porosity. Both reduced surface tension and reduced osmolality caused tissue destruction shown as darker visual color. Addition of surfactant resulted in a high drying rate on a surface area basis corresponding to 15% more water lost after 2 h. The results indicate that biological mechanisms related to function and structure of living tissue are important for drying behavior. The apple ring model is suitable for further studies of biological and other types of drying behavior in relation to the tissue organization. 2011-03-07T00:00:00Z Bengtsson, G. B. og Rahman, M. S. og Stanley, R. A. og Perera, C. O. http://espace.library.uq.edu.au/view/UQ:282575 2012-09-28T13:33:27Z Henry, Robert J. og Edwards, Mark og Waters, Daniel L. E. og Krishnan, S. Gopala og Bundock, Peter og Sexton, Timothy R. og Masouleh, Ardashir K. og Nock, Catherine J. og Pattemore, Julie http://espace.library.uq.edu.au/view/UQ:231508 2011-03-07T00:00:00Z Blackall, P. og Pahoff, J. og Fegan, N. og Marr, G. http://espace.library.uq.edu.au/view/UQ:297310 2013-04-12T17:09:53Z McLennan, S. og Poppi, D. http://espace.library.uq.edu.au/view/UQ:231745 2011-03-07T00:00:00Z Bock, R. E. og Lew, A. E. og Minchin, C. M. og Jeston, P. J. og Jorgensen, W. K. http://espace.library.uq.edu.au/view/UQ:228582 PCR primers based upon sequences from barley alpha-amylase genes were investigated for use in cereal species and variety identification. Eight primers were designed to explore regions of possible polymorphism in this gene family in maize, barley, sorghum, rice, oat and wheat. Some primers gave products characteristic of the species allowing distinctions between oat and wheat and between barley and wheat. However, in general these primers were not useful for species identification because of intra-species polymorphism. The primer combination BAS1/BASZ was the most useful combination for distinctions within species, showing high levels of polymorphism for sorghum and maize varieties, while the primer combination BSW3/BAS2 appeared useful for variety discrimination in rice and maize. PCR with these primers should prove valuable for variety identification in sorghum, maize and rice. In other cases however, individual pairs of Q-amylase primers did not express sufficiently high levels of intra-species polymorphism to be considered for variety fingerprinting or were only useful for identification within small sets of samples. 2011-02-09T00:00:00Z Ko, H. L. og Weining, S. og Henry, R. J. http://espace.library.uq.edu.au/view/UQ:296688 2013-04-10T14:15:12Z Haque, Ahsanul og Galea, Victor og Goulter, Ken og Bissett, Andrew og van Klinken, Rieks D. http://espace.library.uq.edu.au/view/UQ:232020 2011-03-07T00:00:00Z McCown, R. L. og Hammer, G. L. og Hargreaves, J. N. G. og Holzworth, D. og Huth, N. I. http://espace.library.uq.edu.au/view/UQ:232022 2011-03-07T00:00:00Z McCown, R.L. og Hammer, G.L. og Hargreaves, J.N.G. og Holzworth, D.P. og Freebairn, D.M. http://espace.library.uq.edu.au/view/UQ:266749 2012-02-03T11:01:57Z Chauhan, Yashvir S. og Wright, Graeme C. og Holzworth, Dean og Rachaputi, Rao C. N. og Payero, José O. http://espace.library.uq.edu.au/view/UQ:228496 Wild white lupins have high levels of alkaloids, which cause a bitter taste, whereas domesticated white lupin varieties have a very low content of alkaloids in seeds. Genes for bitterness from wild white lupins are a contamination threat to domesticated white lupin via cross-pollination. The gene(s) for alkaloid synthesis have not been clearly identified, and the associated molecular background among wild white lupin, domesticated and contaminated domesticated plant materials is unknown. So far, only tigloyl-CoA:(−)-13alpha-hydroxymultiflorine/(+)-13alpha-hydroxylupanine O-tigloyltransferase (HMT/HLTase) cDNA has been cloned based on protein analysis, which was suggested as encoding a quinolizidine alkaloid transferase regulating quinolizidine alkaloid biosynthesis. This gene has not yet been well characterised in important white lupin genotypes. In this study, we found that the majority of the intron sequence of the HMT/HLTase gene differed between wild white lupin accessions P25758 and P27593, and between the commercial varieties. The expression pattern as well as the expression level of the HMT/HLTase gene showed no difference between the P25758 and the low-alkaloid variety Kiev mutant, suggesting the expression of the HMT/HLTase gene has no correlation with bitterness. However, the intron sequence is useful as a DNA marker in the identification of the contamination source of bitter seeds in commercial lupin seed lots. 2011-02-09T00:00:00Z Chen, Y. og Lee, L. S. og Luckett, D. J. og Henry, R. og Hill, H. og Edwards, M. http://espace.library.uq.edu.au/view/UQ:286581 2012-12-02T00:00:00Z Klieve, A. V. og Ouwerkerk, D. og Maguire, A. J. http://espace.library.uq.edu.au/view/UQ:231441 This paper examines some of the factors that affect the expression of libido in beef cattle, focusing on the male and the free-ranging situation. The ways in which bull libido is assessed and the relationship between libido test results and fertility are discussed. Genetics play a role in determining libido, but there are many environmental factors affecting its expression, and a number of these factors influence sexual activity in both tests of libido and paddock mating. Herd fertility is multi-factorial and, consequently, it is difficult to draw definitive conclusions about the relationship between libido and fertility. Multiple males increase the expression of libido, but it is uncertain whether this translates into improvements in herd fertility. However, there are consequences for individual bull fertility, as there is ample evidence of inherent differences between bulls. Male:female ratios appear to have minor effects on libido and fertility. Anecdotal evidence indicates that multiple matings with the same or different bulls may reduce the duration of oestrus. Social relationships between bulls can affect the expression of libido, with subordinate bulls being inhibited by the presence of dominant bulls. There is evidence that dominant bulls may achieve more matings at pasture, but this is not necessarily shown in their fertility. Older bulls show greater expression of libido in tests and appear more efficient in serving, although these changes may reflect greater sexual experience. Provided bulls are sexually mature and physically able to mate, age per se appears not to affect fertility, but age interacts with dominance, which can influence fertility. There is evidence of breed differences in expression of libido, but this appears not to be demonstrated in fertility. There is anecdotal evidence that bulls and females prefer to mate with similar genotypes/phenotypes with implications for fertility. Limited research on thermal and nutritional effects indicate some adverse consequences for libido of climatic extremes for unadapted bulls and of over-feeding, but not under-feeding. Limited research has investigated the effects on libido and fertility of multiple stressors associated with relocation; relocation to dramatically different environments has long-lasting detrimental consequences for fertility. Too few studies have been conducted to draw conclusions about the effects of topography and herd dispersion on libido and fertility. Temperament is likely to affect the expression of libido when animals are put into new situations, but this has not been critically researched. In the light of this review, the implications for managing cattle to optimise fertility are discussed and suggestions made as to areas where further research is needed. 2011-03-07T00:00:00Z Petherick, J. C. http://espace.library.uq.edu.au/view/UQ:273963 Since the first investigation 25 years ago, the application of genetic tools to address ecological and evolutionary questions in elasmobranch studies has greatly expanded. Major developments in genetic theory as well as in the availability, cost effectiveness and resolution of genetic markers were instrumental for particularly rapid progress over the last 10 years. Genetic studies of elasmobranchs are of direct importance and have application to fisheries management and conservation issues such as the definition of management units and identification of species from fins. In the future, increased application of the most recent and emerging technologies will enable accelerated genetic data production and the development of new markers at reduced costs, paving the way for a paradigm shift from gene to genome-scale research, and more focus on adaptive rather than just neutral variation. Current literature is reviewed in six fields of elasmobranch molecular genetics relevant to fisheries and conservation management (species identification, phylogeography, philopatry, genetic effective population size, molecular evolutionary rate and emerging methods). Where possible, examples from the Indo-Pacific region, which has been underrepresented in previous reviews, are emphasized within a global perspective. 2012-05-14T21:28:29Z Dudgeon, C. L. og Blower, D. C. og Broderick, D. og Giles, J. L. og Holmes, B. J. og Kashiwagi, T. og Kruck, N. C. og Morgan, J. A. T. og Tillett, B. J. og Ovenden, J. R. http://espace.library.uq.edu.au/view/UQ:292222 The fungal genera Ustilago, Sporisorium and Macalpinomyces represent an unresolved complex. Taxa within the complex often possess characters that occur in more than one genus, creating uncertainty for species placement. Previous studies have indicated that the genera cannot be separated based on morphology alone. Here we chronologically review the history of the Ustilago-Sporisorium-Macalpinomyces complex, argue for its resolution and suggest methods to accomplish a stable taxonomy. A combined molecular and morphological approach is required to identify synapomorphic characters that underpin a new classification. Ustilago, Sporisorium and Macalpinomyces require explicit re-description and new genera, based on monophyletic groups, are needed to accommodate taxa that no longer fit the emended descriptions. A resolved classification will end the taxonomic confusion that surrounds generic placement of these smut fungi. 2013-02-24T01:07:33Z McTaggart, A. R. og Shivas, R. G. og Geering, A. D. W. og Vanky, K. og Scharaschkin, T. http://espace.library.uq.edu.au/view/UQ:250763 2011-09-11T00:00:00Z McGoverin, Cushla M. og Snyders, Franci og Muller, Nina og Botes, Willem og Fox, Glen og Manley, Marena http://espace.library.uq.edu.au/view/UQ:231966 2011-03-07T00:00:00Z Fukai, S og Hammer, G. L. http://espace.library.uq.edu.au/view/UQ:240256 2011-04-19T00:00:00Z Fortes, M. R. S. og Reverter, A. og Nagaraj, S. H. og Zhang, Y. og Jonsson, N. N. og Barris, W. og Lehnert, S. og Boe-Hansen, G. B. og Hawken, R. J. http://espace.library.uq.edu.au/view/UQ:254265 2011-10-06T00:00:00Z Chen, Y. og Piper, E. og Zhang, Y. og Tier, B. og Graser, H. U. og Luxford, B.G. og Moran, C. http://espace.library.uq.edu.au/view/UQ:286949 2012-12-09T00:30:56Z Debaeke, P. og van Oosterom, E. J. og Justes, E. og Champolivier, L. og Merrien, A. og Aguirrezabal, L. A. N. og Gonzalez-Dugo, V. og Massignam, A. M. og Montemurro, F. http://espace.library.uq.edu.au/view/UQ:231993 2011-03-07T00:00:00Z Hammer, G.L. og Muchow, R C http://espace.library.uq.edu.au/view/UQ:232036 Rainfed crop production in the subtropics is a risky enterprise due to high rainfall variability. When planting opportunities occur, farmers face risky choices because the consequences of decisions made at planting are uncertain. This paper presents a general approach to generating the information required to assistt in making planting decisions in climatically variable subtropical environments. The approach involved coupling a sorghum growth simulation model to long-term sequences of climatic data to provide probabilistic estimates of yield for the range of decision options, such as planting time and cultivar maturity, for a range of soil conditions. The likely change in the amount of stored soil water with delay in planting was also simulated to account for the decision option of waiting for a subsequent planting opportunity. The approach was applied to three locations (Emerald, Dalby and Roma) in subtropical Australia. Production risk varied with location, time of planning, soil water storage, and cultivar phenology. Yield responses to these factors were associated closely with differences in leaf area development and degree of depletion of the water resource. The probabilistic estimates of yield and change in stored soil water provided in this paper can assist decision-makers with risky choices at planting in subtropical environments. Such information can be used in decision analysis or in computerized decision support, where decision-makers, and their risk preferences, can interact directly with the information. 2011-03-07T00:00:00Z Muchow, R.C. og Hammer, G.L. og Vanderlip, R.L. http://espace.library.uq.edu.au/view/UQ:232788 Grain samples from a combined intermediate and advanced stage barley breeding trial series, grown at two sites in two consecutive years were assessed for detailed grain quality and ruminant feed quality. The results indicated that there were significant genetic and environmental effects for "feed" traits as measured using grain hardness, acid detergent fibre (ADF), starch and in-sacco dry matter digestibility (ISDMD) assays. In addition, there was strong genotypic discrimination for the regressed feed performance traits, namely Net Energy (NE) and Average Daily Gain (ADG). There was considerable variation in genetic correlations for all traits based on variance from the cultivars used, sites or laboratory processing effects. There was a high level of heritability ranging from 89% to 88% for retention, 60% to 80% for protein and 56% to 68% for ADF. However, there were only low to moderate levels of heritability for the feed traits, with starch 30-39%, ISDMD 55-63%, ADF 56-68%, particle size 47-73%, 31-48% NE and ADG 44-51%. These results suggest that there were real differences in the feed performance of barleys and that selection for cattle feed quality is potentially a viable option for breeding programs. 2011-03-07T00:00:00Z Fox, Glen P. og Bowman, Jan og Kelly, Alison og Inkerman, Andy og Poulsen, David og Henry, Robert http://espace.library.uq.edu.au/view/UQ:232059 High rainfall variability in the subtropics makes rainfed crop production a risky enterprise. Planting opportunities are limited by the amount and timing of rainfall. Farmers face a decision of whether or not to plant when an opportunity occurs. This decision depends on the likely yield from different crops and cultivars, the probability of obtaining another planting opportunity, and the yield expectation from that later planting. In this paper, long-term climatic data for six locations in subtropical Australia were used to (i) compare criteria for identifying planting opportunities; and (ii) determine the frequency of occurrence of planting opportunities and the duration between opportunities. Although the occurrence of planting opportunities varied among months and locations depending on the criterion used, very few planting opportunities occur in these environments and the duration between opportunities is relatively long. The mean number of planting opportunities was never greater than one for any month at any location, and frequently (30-70% of years) no planting opportunities occurred in a given month. The highest probability of another planting opportunity occurring in the 30 days following an opportunity was 60%; in most cases the probability was much less. While the results are specific to the locations analyzed, the approach developed is generally applicable where quantifying the risk of planting opportunities is important to decisionmakers. 2011-03-07T00:00:00Z Vanderlip, R.L. og Hammer, G.L. og Muchow, R.C. http://espace.library.uq.edu.au/view/UQ:270996 2012-03-21T00:00:00Z Aitken, Elizabeth http://espace.library.uq.edu.au/view/UQ:265715 2012-01-22T00:00:00Z Werth, Jeff og Thornby, David og Walker, Steve http://espace.library.uq.edu.au/view/UQ:228595 2011-02-09T00:00:00Z Osborne, B. G. og Henry, R. J. og Southan, M. D. http://espace.library.uq.edu.au/view/UQ:254268 2011-10-06T00:00:00Z Piper, E. og Chen, Y. og Moran, C.