Browsing by Browse by SEO 2020 "100501 Browse crops"
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Publication Open AccessJournal ArticleAcceptance of novel food by horses: The influence of food cues and nutrient composition(Elsevier BV, 2016); ; ; Compared to ruminants little is known about how horses modulate food intake and learn about flavour-to-post-ingestive consequences. While it has been suggested that due to hindgut fermentation horse's foraging preferences may be largely influenced by sensory input (e.g. volatiles), it has been established that horses are able to differentiate and select familiar foods (e.g. concentrates and hay) based on nutritional content. Yet it remains unclear how this translates to the acceptance of nutritious novel foods (NF). Therefore, the influence of food cues and nutrient composition on NF acceptance were examined in two experiments using 11 adult mares. In experiment 1, we investigated the influence of a familiar odour (FO) on the acceptance of a nutritious NF and in experiment 2, we determined if horses have the ability to select nutritious NF based on the nutritional content, regardless of sensory preferences. In experiment 1 horses received identical NF in a two-choice test with one of the choices being masked with a FO over a 9-day period. In experiment 2 horses were offered a high or low protein option of an otherwise identical NF in a two-choice test in which the NFs were paired with two unfamiliar flavours (odours). The two-choice test lasted for 14 days and the flavour-protein pairing was switched after 7 days. NF intakes were recorded over a 10 min test period on each test day and analysed using Bayesian hierarchical models. The results of experiment 1 indicate that a FO had a strong positive influence on the NF intake for the first 5 days (90-100% of total consumption and strong evidence for non-zero temporal effects (Bayes factor B12= 110)). This was followed by a more even distribution of intake for the remaining period. In experiment 2 horses had a greater intake of high protein NF regardless of the flavour on days 4, 6 and 7 (80-87% of total consumption) and this continued after the switch over (Day 9-14; 57-81% of total consumption). However, 4 out of 11 horses showed neophobia throughout the testing period, which could have been associated with the novel odours as horses scanned the buckets with little to no sampling. The results suggest that pre-ingestive cues (e.g. smell, taste) of foods play an important role in diet selection and that a FO can increase the acceptance of NF. This new knowledge could be applied by the horse industry to encourage the consumption of new food or forages by horses.2239 388 - Some of the metrics are blocked by yourconsent settings
Publication Open AccessThesis DoctoralBehavioural mechanisms of diet selection by horses(2016); ; Compared to ruminants little is known about how horses modulate food intake and link the sensory properties (e.g. smell, taste) of foods with its post-ingestive consequences (negative and positive). While it has been suggested that horse’s foraging preference may be largely influenced by sensory input (e.g. volatiles, taste), because of hindgut fermentation, it has been established that horses are able to differentiate and select familiar foods (e.g. concentrates and hay) based on the nutritional content. However, there is a lack of knowledge of behavioural mechanisms related to olfaction, gustation and somatic sensory perception and their effects on diet selection by horses. In particular little is known of how these mechanisms may operate in pastured environments where horses are often exposed to a variety of plant patches, including familiar and novel species that may differ in flavour, nutrient concentrations and plant toxins throughout the year. The aim of this thesis was to further develop an understanding of behavioural mechanisms influencing diet selection by horses and in particular to determine how they identify and select amongst a variety of foods (familiar and/or novel) using sensory perception and post-ingestive feedback. A series of experiments examined: (1) The selection of familiar and novel forages using a checkerboard design to simulate patch foraging conditions. As changes in dietary preferences are largely influenced by the nutritional requirements of the animal and palatability of a food, it was of interest to investigate the effect of the nutritional status (energy intake) on novel forage selection by horses; (2) The influence of orosensory (smell) stimuli and post-ingestive feedback in the recognition of novel foods by horses. This was achieved by assessing the acceptance of a novel food with a familiar odour or with contrasting crude protein levels; and (3) The influence of different food characteristics i.e. nutrients, odour and taste, on the voluntary intake and preferences of horses exhibited when a number of foods were offered simultaneously (i.e. Smörgåsbord). In each experiment between 11 and 16 horses of Thoroughbred, Standardbred or Australian Stock Horse breeds were used. The findings of this thesis suggest that horses can respond to the nutritional content of foods, even if these are novel. There was a greater acceptance and intake of novel foods that contained a higher level of crude protein, and energy intake seemed to have a lesser impact on the intake of novel foods. It was also observed that the acceptance and intake of a novel food was largely influenced by the orosensory characteristics (smell, taste, texture), and possibly an individual’s experience. The thesis also shows that horses display patch foraging behaviour sampling from all foods on offer. When familiarised with diets horses clearly rank these based on nutrients, followed by taste and then odour. Further studies should assess the adoption of multiple-choice tests and nutritional geometric models to enhance our understanding of diet selection patterns by horses in different environments. In particular how individual animals may regulate the intake of multiple nutrients to meet dietary requirements. Whilst macronutrients may be the main driver for diet selection - the impact of the sensory perception on diet choice cannot be disregarded. This thesis highlights that familiar odour and taste cues could be applied in equine feeding management to increase food acceptance when forages/foods are scarce, during introduction of new foods or forage batches or when horses are moved to different environments.4156 1183 - Some of the metrics are blocked by yourconsent settings
Publication Best practice weed detection on Australian farmsAgricultural weeds impose a significant cost on Australian farmers and consumers. The first step in controlling weeds on-farm is successful detection. The sooner new weed invasions are detected, the more effective management strategies will be. This research sought to collate 'best practice' principles for weed detection by surveying those individuals who play a part in weed detection and control on Australian farms - landholders and weeds officers. We found that landholders regularly checked their property for weeds, but were often reluctant to report new weed outbreaks. Weeds officers had an important role in improving weed detection on-farm, by providing advice and information to landholders, and encouraging more landholders to report weed outbreaks. While there were many similarities in the best practice approaches used by landholders and weeds officers to inspect land for weeds, weeds officers had access to a range of resources that made it considerably easier to identify a new weed species. It was also found that there were particular segments within the broad landholder group (such as non-professional landholders), who were considered relatively poor weed managers. Extension work in this area therefore needs to encourage close cooperation with weeds officers, targeting specific landholder groups for extension and access to expert advice, while continuing to educate all landholders in the areas of weed identification, and the best practice detection and control techniques used by weeds officers.1374 1 - Some of the metrics are blocked by yourconsent settings
Publication Browse-related behaviors of pastured horses in Australia: A surveyThis study investigated the husbandry and management practices of Australian horses at pasture and observed browsing behavior (i.e., the consumption of nonpasture plant species). Horse owners were contacted via horse magazines, social media Web sites, and horse industry councils and invited to complete an online survey. Information was collected on location, husbandry, and feeding management of their horse(s), pasture conditions, the observation of specified behaviors and forage selection by their horse(s) at pasture. The survey had 497 respondents across Australia who owned a total of 3,082 horses. Most horses (85%) had access to grazing areas 16-24 hours per day. Owners commonly (90%) observed ≥1 pasture problems on their property, and the mean number of problems was similar across grazing areas of <2, 2-10, and >10 ha. Although the horses had access to pasture, there was a heavy reliance on supplementary feeding. Approximately 95% of the horses were fed concentrates and/or supplements on a daily basis, and 86% of the horses were offered conserved forage. Surveyed behaviors were reported by 75% of the respondents, with bark chewing and licking or eating dirt being the most prevalent behaviors. Almost three-quarters of the horse owners indicated that their horses browse on parts of trees, shrubs, or other nonpasture species. This study verifies that Australian horses consume a range of nonpasture species and frequently demonstrate bark-chewing behavior while at pasture. It is currently unclear if the selections of browse and bark stripping observed in this study are a function of reduced pasture availability or vegetation diversity and diet choices.2205 - Some of the metrics are blocked by yourconsent settings
Publication Open AccessJournal ArticleChanges in botanical composition on three farmlets subjected to different pasture and grazing management strategies(CSIRO Publishing, 2013); ; ; 1236 - Some of the metrics are blocked by yourconsent settings
Publication Dietary energy intake does not influence diet selection of familiar and novel forages by horses(University of Leipzig, 2014); ; ; Equine studies have been able to show that horses have the ability to discriminate nutrient deficit diets or "balance" macronutrients (e.g. protein or carbohydrates) by increasing their intake or changing food preference (Laut et al., 1985; Cairns et al., 2002; Redgate et al., 2014). These studies used either familiar concentrates or forages alone, but in grazing systems horses are likely to exploit familiar foods in combination with novel foods on a continuous basis. The acceptance of nutritious novel foods and the influence of the animal's nutritional status on diet selection (e.g. partial preferences) warrant further research. Therefore this study aimed to investigate the effect of energy intake on foraging behaviour patterns in horses and the selection of familiar (FF) and novel (NF) forages. It was hypothesised that horses would have a preference for FF, but horses on a low energy diet would show a greater acceptance of the nutritious NF.1733 - Some of the metrics are blocked by yourconsent settings
Publication Estimating the value of genetic gain in perennial pastures with emphasis on temperate species(CSIRO Publishing, 2014); 2190 - Some of the metrics are blocked by yourconsent settings
Publication Farming the Web of Things(Institute of Electrical and Electronics Engineers (IEEE), 2013); ; Primary industry in Australia has a proud record of both remarkable productivity and investment in innovation. The combine harvester, for example, revolutionized broad-acre crop production after its first commercial production in Australia in 1885. Today, there are new economic pressures driving a new round of information-based innovation, this time aligned with the technology push called the 'Web of Things'. Since 1999, it has been mandatory for all Australian farmer to affix passive RFID ear tags to their cattle and to report movements between farms to a national database. Now, the first commercial systems for on-farm livestock location tracking are emerging; the Taggle system, for example, triangulates wireless signals from active ear tags as they are received at base station antennae. A national broadband network is being developed to deliver telephony and high-speed broadband to all Australian homes, schools, and businesses, including rural farms. Farming "things" are becoming electronically identifiable and measureable, but the "Web" that connects and adds value is largely unexplored.2775 - Some of the metrics are blocked by yourconsent settings
Publication Open AccessThesis DoctoralImpacts of forage legumes on smallholder crop-livestock systems in West Timor, Indonesia(2018-04-14); Smallholder crop-livestock systems are critical to future food security and meeting rapidly rising demand for livestock products. Yet, increasing competition for resources and high levels of soil degradation means farmers must produce more agricultural outputs without using more land, water or other inputs. Herbaceous forage legumes are one strategy for intensifying crop-livestock systems. However, current adoption levels are low and there is great uncertainty over the benefits, trade-offs and constraints of integrating forage legumes into farming systems at a farm and household level. Forage legume research has largely focused on agronomic performance and, consequently, the socio-cultural and economic factors which define the potential role of forage legumes in smallholder farming systems are poorly understood. Critically, little consideration has been given to the impact of gender roles on forage legume adoption and the distribution of impacts within a household. This thesis identifies potential opportunities for integrating forage legumes into smallholder crop-livestock systems in West Timor, Indonesia, and the benefits and trade-offs at a farm and household level.
The impact of forage legumes on farm production depends on the allocation of legume nitrogen (N) to crop and livestock enterprises. In Chapters 2 and 3, the impact of forage legume biomass management (retained vs. cut and removed) on inputs of fixed N, soil N and subsequent maize yield was assessed for an irrigated field experiment. While retaining shoot biomass contributed equivalent to 100-150 kg urea-N/ha and increased maize yield by 6-8 t/ha, there was little or no yield benefit when legume biomass was removed. The N fixation efficiencies (9-27 kg fixed-N/t shoot DM) and maize yield responses (5.8-7.9 t/ha higher yield compared to a maize control) were also double what is commonly achieved under dryland systems, indicating effective soil N and water management and sufficient yield potential are required to realise meaningful production benefits. As large trade-offs exist between allocating legume N to crop or livestock enterprises, alternative management options, such as grazing or partial biomass removal, may be required to achieve dual soil N-fodder benefits. Good agronomic practice is required to maximise the yield benefits of forage legumes. In Chapter 4, simulations for six case study sites in West Timor indicated that increases in maize yield of up 3.5 t/ha could be achieved if legume shoot biomass was retained, maize was planted at high densities (4-6 plants/m2) and weed control was effective. Critically, in West Timor, plant available water rather than soil N constrained crop production in poor years. Thus, the largest and most consistent yield responses from forage legume production are likely to be achieved for years and sites with low soil N fertility and high rainfall.
Despite the yield benefits of green manuring legume biomass, farmers often favour allocating biomass to increasing livestock production, as it provides more substantial economic benefits. In Chapter 5, whole farm and participatory modelling quantified the production and economic impacts of forage legumes for six case study farms. When used as fodder, forage legumes can more than double farm income, although they must be integrated with staple crops or planted on unutilised land to achieve such substantial benefits. The marginal value of feed increased with herd size from 0.9-1.0 M Rp/t TLU-1 for smaller herds (≤2 TLU) to 1.8-3.1 M Rp/t TLU-1 for larger herds (>2 TLU), indicating there were larger economic benefits for larger herds (TLU; Tropical Livestock Unit). Participatory scenario analysis indicated that livestock focused farmers favoured larger areas of legumes than other farm types. This indicates that farmers with sufficient incentive, land, labour and capacity to invest are likely to benefit most from forage legumes.
While forage legumes can provide large economic benefits, the impacts of technologies are often unevenly distributed between men and women. In Chapter 6, participatory onfarm evaluation assessed the potential benefits and constraints of forage legume production for male and female farmers. Preferences reflected gender roles; women favoured integrating forage legumes with food crops to increase soil fertility and crop yield, while men favoured permanent stands as they provided the largest economic benefit. Labour was identified as the key constraint to adoption, with unequal distribution of household labour suggesting that forage legumes may increase women's labour requirements but maintain or decrease men's labour requirements. Thus, forage legume adoption requires labour saving options and more equitable distribution of benefits and labour inputs between men and women.
This research demonstrated that integrating forage legumes into smallholder croplivestock farming systems can provide significant production and economic benefits. Yet, there are also large trade-offs associated with legume management, labour, land use and the inequitable distribution of household impacts. Further research is required to validate these potential impacts and how they may differ for a broader range of farmers and farming systems.
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Publication Open AccessJournal ArticleThe influence of odour, taste and nutrients on feeding behaviour and food preferences in horses(Elsevier BV, 2016); ; ; 2260 98 - Some of the metrics are blocked by yourconsent settings
Publication Open AccessJournal ArticleMultilevel innovation platforms for development of smallholder livestock systems: How effective are they?(Elsevier BV, 2021-04); ; ; ; Duncan, Alan JContext: There is growing recognition that sustainable development of smallholder agriculture in Sub-Saharan Africa requires a systems approach. One response to this has been applying the agricultural innovation systems concept and the use of Innovation Platforms (IP) as tools for agricultural development. By providing social space and facilitating interactions among farmers, researchers and other stakeholders, IPs can promote collective action and foster innovation.
Objective: The question is, how effective are these IPs in stimulating innovation that can be sustained beyond their lifetime, and can they be used to link issues across multiple scales? The case study reported here examined the effect of a multilevel IP structure in achieving smallholder livestock innovation outcomes in the Ethiopian Highlands.
Methods: Two years after the multilevel IPs were phased out, focus group discussions and key informant interviews with multiple stakeholders from all levels of the IP were undertaken to collect qualitative data on the innovation processes and analysed using thematic analysis.
Results and Conclusions: Our findings indicate that a series of IPs inter-linked across scales facilitated researcher-led technical innovations that enhanced farmers and livestock experts' capacity around feed technologies. The multilevel IPs also improved linkages and strengthened partnerships between actors within and across levels to effectively implement farm-level technologies. However, sustained innovation requires creating a shared understanding among actors on the complex nature of the various value chain issues that need to be addressed to achieve meaningful change. Specifically, we found that farmers lack access to affordable services. This requires integrating value chain concepts within multilevel IPs at the early stages of formation to engage relevant actors across levels to stimulate multiple interventions beyond the farm-level.
Significance: Changes are needed at the organisational level to facilitate reconfiguration of resources and devolution of responsibilities to support the innovation process. The existence of power dynamics and an institutional context favouring the status quo are key issues that need to be considered when building and evaluating effective multilevel IPs to achieve inclusive value chain innovations.1278 5 - Some of the metrics are blocked by yourconsent settings
Publication Relative occurrence of stereotypic type behaviours in pastured horses in Australia(Australasian Equine Science, 2014); ; ; Anecdotally, Australian horses are typically managed on small acreage pastures (paddocks) all year round and may be confined to stables or yards for certain periods. Even where horses have considerable access to pasture, they remain largely dependant upon humans for pasture management and the timing, selection and delivery of supplementary feeds. Horses are usually fed in ways that involve minimal foraging; and typically comprise homogenous hay, and/or energy-dense, low fibre foods. In situations where roughage or pasture is limited, opportunity to forage is also reduced and it has been suggested that this could make horses more susceptible to digestive and behavioural problems (Nicol, 1999). Stereotypic behaviours are repetitive, purposeless behaviours, which are indicative of welfare issues. Some examples in horses include crib-biting, weaving and chewing of stable bedding. Occurrences of stereotypies in horses have been predominantly reported in stable environments, but have also been observed at pasture. An Australian study by Pell and McGreevy (1999) indicated that the prevalence of such behaviours at pasture was not lower than the prevalence reported in a UK study (McGreevy et al., 1995). It is unclear what factors may play a role in to this observation. Therefore, as part of a survey-based study, the relative occurrence of stereotypic type behaviours of Australian horses at pasture was examined and key aspects of husbandry, feeding management and pasture conditions assessed.1846 - Some of the metrics are blocked by yourconsent settings
Publication Surviving the data deluge: geostatistical and signal processing methodologies for smart farm sensor networks(University of New England, 2013); ; ; ; ; There is a trend towards the deployment of more and more soil, plant, animal, asset, and machinery performance sensors on the farm. More sensors mean more data, especially if it is generated in live streams and it remains a significant challenge for it to be distilled to a manageable size and rendered in a useable form. Seemingly simple and intuitive 'front-ends' require specialised and complex algorithms and software working behind the scenes. The SMART FARM sensor network is an example of a future farm technology which can generate very large data sets. This network monitors meteorological and soil conditions over an area of approximately 500 acres. There are 100 nodes equipped with multiple sensors all transmitting data back to a central server at 5 minute intervals, 24 hours a day, 7 days a week. In this paper we will survey the range of statistical and computing tools being developed by the SMART FARM team to render this information rich data field into management-relevant information including visualisation, detection and understanding of trends, and generating critical state alarms.1849 - Some of the metrics are blocked by yourconsent settings
Publication Use of plant water relations to assess forage quality and growth for two cultivars of Napier grass ('Pennisetum purpureum') subjected to different levels of soil water supply and temperature regimes(CSIRO Publishing, 2013); ; ; 1183 - Some of the metrics are blocked by yourconsent settings
Publication Utilisation of Leucaena leucocephala foliage, toxicity risk and management in ruminant breeding production systems(University of New England, 2023-09-04); ; Leucaena has been shown to provide good nutritional value for ruminant fattening systems all over the world. However, there is still some debate concerning its suitability and safety for ruminant breeding stock despite the new paradigm regarding the detoxification mechanisms of leucaena toxicity that has been revealed recently. Therefore, the objectives of this thesis were to: 1) examine the application of this novel theory of detoxification in leucaena production systems, with special attention to breeding stock" 2) To clarify how breeding ruminants are susceptible to the effects of leucaena toxins" 3) to determine whether leucaena toxin effects on fertility could be mitigated by up-regulating detoxification processes, and 4) to identify methods for supporting or up-regulating detoxification mechanisms. One literature study, a survey and two controlled experiments were conducted to address these objectives.
A literature review (Chapter 2) identified the effects of leucaena feeding, and also the possible mechanisms involved to obstruct the reproductive function of breeding ruminants. A survey (Chapter 3) clarified the role and the utilisation of leucaena in breeding enterprises as well as the impact of leucaena toxicity in breeders. Next, a trial with rams (Chapter 4) investigated the impact of leucaena toxins, mimosine and DHP on male fertility. Meanwhile, the cassava trial (Chapter 5) was conducted to test a potential strategy to deal with DHP toxicity and also to support the current paradigm of leucaena detoxification.
The key findings of this thesis are:
Leucaena is crucial to provide cattle in the tropics, particularly in eastern Indonesia, with a high-quality feed in order to improve performance and promote more intensive, productive, and profitable cattle enterprises. Leucaena was mostly used by farmers for breeding cattle as a strategic feed resource during the dry season and at particular periods of pregnancy, whereas the majority of their focus was on fattening cattle solely.
Leucaena toxins can temporarily impair male fertility by adversely affecting sperm motility and proximal cytoplasmic droplet abnormalities for 5 - 7 weeks after exposure in leucaena-naive ruminants, but the mechanism is not 2,3-DHP. Two possible mechanisms are proposed as the cause of the leucaena-induced reduction in sperm quality observed in this thesis. Firstly, mimosine, which acts as an antimitotic agent by targeting germ cells involved in the mitotic proliferation of the sperm production cycle (spermatogenesis). Another mechanism could be the action of phytoestrogens in leucaena foliage, which can increase germ cell death or apoptosis, resulting in decreased sperm motility and testosterone levels.
Glucuronic conjugation in the liver is essential for detoxifying leucaena toxins, and it can be upregulated very quickly even in the absence of highly digestible energy sources in the diet.
Indigenous microbes in the rumen of animals naïve to leucaena cannot quickly and completely degrade mimosine and DHP into non-toxic substances. Therefore, before introducing leucaena for the first time, this thesis strongly suggests inoculating truly naive animals with leucaena-toxin-degrading bacteria to enhance the efficacy of mimosine/DHP-degrading bacterial populations to rapidly and thoroughly degrade mimosine into less toxic products for further detoxification in the liver.
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