Browsing by Browse by FOR 2020 "300210 Sustainable agricultural development"

Innovation contexts and associated elements determine the type of innovation and adoption. This study aimed at the understanding of the innovation policy and intervention mechanism within the Bhutanese Department of Agriculture (DoA). We developed a conceptual model from the themes and the OECD evaluation criteria based on the conceptual model. The national issues and opportunities related to the agriculture and forestry of Bhutan were defined, and policy gaps were identified between the national plan and the institutional programs that were implemented. A total of 67 government documents from the relevant agencies were collected, of which, 33 documents were included, based on the inclusion criteria that matched with the conceptual, thematic analytical model. Our results from the document analysis show that the institutional innovative interventions appeared relevant to the Bhutanese context; however, inadequate coherence (mapping and alignment) of the institutional intervention programs with the national issues and goals suggested the need for the Bhutanese agricultural innovation system to enhance the effectiveness and efficiency of the program results. Similarly, coordination and collaboration were found to be necessary to extract the synergistic impact of the innovative interventions at the various levels of administrative hierarchy. Institutional accountability and interventional coherence at different organisational levels needs reviewing in order to achieve the sustainability of the outcome in Bhutanese agricultural research.

Five industry-relevant animal experiments were completed to investigate amino acid supplementation in reduced protein diets and the impacts on meat-chicken performance, metabolism, and physiology. Specifically, the role of the non-essential amino acid glycine in reduced protein wheat-based diets was investigated. This work was developed in response of increasing expenses and environmental impacts associated with current dietary crude protein levels in broiler diets, however, reducing the crude protein and supplementing all assumed essential nutrients typically results in impaired performance. The work completed in this thesis contributes to our understanding of broiler amino acid requirements in reduced protein wheatbased diets.

The first experiment investigated the role of the non-essential amino acid, glycine, in broiler performance when fed reduced protein wheat-based diets. An industry-standard protein diet and three reduced protein diets with and without glycine supplementation were fed to Ross 308 cockerels. Glycine was supplemented to equal that in the standard protein diet at 0.712 and 0.648% in grower and finisher diets respectively. Performance, water intake, and amino acid digestibility were measured. Reducing crude protein reduced body weight gain by up to 18% and reduced water intake by 28%. However, supplementing glycine in reduced protein diets restored the impaired performance and increased water intake. Supplementing crystalline amino acids in reduced protein diets increased their respective apparent ileal digestibility, with the greatest difference in threonine digestibility increasing by up to 8.3 percentage points. When feeding reduced protein wheat-based diets, supplementing crystalline amino acids, including glycine, can maintain performance like that observed in standard protein diets.

A second experiment was completed to determine if supplementing glycine precursors have the same effect on performance as glycine in reduced protein diets. Ross 308 cockerels were fed one of two protein levels; an industry-standard protein diet with meat and bone meal or a plant-based diet approximately 3% lower in crude protein. In the reduced protein diet, glycine, serine, and threonine were assigned a glycine equivalence and supplemented to match the glycine in the standard protein diet at 1.558 and 1.390% in grower and finisher diets respectively. Reducing the dietary protein by 3% reduced feed efficiency by 10-points, however, the supplementation of glycine or serine did not restore performance. Threonine supplementation further reduced body weight gain in reduced protein diets by 6.8%. Therefore, glycine did not appear to be limiting in the reduced protein diet investigated, however, using threonine to supplement glycine requirements exacerbated the performance reducing effects of reduced protein diets.

A third experiment explored the effects of different crude protein diets and the supplementation of glycine precursors on the in vivo synthesis of glycine. To investigate this, a second glycine equivalence level was added to the reduced protein treatments described above at 1.8% giving a total of eight treatments. Using these treatments, the effects of reduced protein diets on glycine and uric acid metabolism was investigated. The in vivo conversion of serine and threonine to glycine was evident in the blood plasma, however, reducing dietary protein reduced blood serum uric acid. The expression of hepatic genes for enzymes associated with threonine degradation to glycine, glycine degradation, and uric acid-synthesis were downregulated in reduced protein diets. No effect of crude protein or supplementing different glycine precursors at differing levels was observed on the expression of the enzyme associated with the interconversion of glycine and serine. The supplementation of excess essential amino acids and non-specific nitrogen may not fulfil the non-essential amino acid requirements for efficient growth as the in vivo synthesis of non-essential amino acids is altered in reduced protein diets.

A fourth experiment investigated the differences in performance when increasing both the essential and non-essential amino acid densities by 15% in reduced protein diets. Ross 308 cockerels were fed one of three protein levels; standard, reduced, or low protein, with one of three amino acid profiles using AMINOChick®2.0 (Evonik Animal Nutrition, 2016) software recommendations; 100% amino acids (100% AA), 115% essential amino acids (115% EAA), or 115% amino acids (115% AA). In this experiment, glycine was considered an essential amino acid and formulated to 1.6% glycine equivalence. Performance, nitrogen digestibility, and blood parameters were measured. No significant difference was observed between feeding 100% AA and 115% EAA treatments at each protein level in body weight gain. However, feeding 115% AA increased body weight gain in standard and low protein diets by up to 18.7%. Blood parameters indicated reduced uric acid synthesis in low crude protein diets, despite glycine supplementation. Feeding 115% AA in the standard and low protein treatments increased nitrogen digestibility compared to the other amino acid profiles. The results from this study indicate that non-essential amino acids play key roles in growth and development that cannot be overcome with extra essential amino acid supplementation.

Finally, a fifth experiment assessed the efficacy of low protein diets and increasing amino acid densities by 15% on mitigating the effects of sub-clinical necrotic enteritis. To investigate this, the standard and low protein treatments and the 100% AA, 115% EAA, and 115% AA profiles of the previous experiment were used in birds either challenged or not with sub-clinical necrotic enteritis. Ross 308 cockerels were fed one of six dietary treatments across 12 replicates. Six replicates per treatment were challenged with sub-clinical necrotic enteritis using Eimeria spp. and Clostridium perfringens. Differences in bird performance between those fed the standard and low protein diets were not apparent in challenged birds. Feeding diets with 115% AA increased body weight gain after the challenge by 10.5%. As evident from the finisher body weight gain, regardless of amino acid profile, low protein diets delayed recovery. However, in standard protein diets, feeding 115% AA increased body weight gain by 16.7%. These results suggest reducing crude protein may not mitigate the effects of sub-clinical necrotic enteritis, however, increasing both essential and non-essential amino acids will assist with recovery.

The work completed has been highly industry-relevant and has highlighted the complex relationships between amino acids and the effects they have on meat-chicken performance, metabolism, and physiology. The Australian chicken meat industry now has a dataset of Australian diets for assessment to consider implementing reduced protein diets to improve industry sustainability and access potential diet cost savings .

Since the 1960s, there has been a progressive development of approaches to agricultural innovation from the linear transfer of technology approach to a system-oriented approach. The widely used systems approach called agricultural innovation systems (AIS) reconceptualises agricultural innovation as being a result of interactions among diverse actors and beyond simple adoption of technological innovation. This approach has mainly been operationalised through a network of actors called innovation platforms (IPs), and current practices with IPs in SubSaharan Africa (SSA) have shown their limitations in stimulating institutional innovations, sustaining innovation, and including farmers in the innovation process (Chapter 1). Using IPs that link lower-level IPs with the higher-level IPs, referred to as multilevel IPs, was seen as having the potential to help in negotiating the complex technological, organisational, and institutional changes required to transform smallholder agriculture and successfully operationalise the AIS approach.

The present research aimed to assess multilevel IPs' effectiveness in attaining and sustaining smallholder livestock technological and institutional innovation outcomes. It has three research questions that seek to identify the effectiveness of the multilevel IPs in attaining innovation, enabling sustained uses of innovation outcomes beyond the project period, and including farmers in the innovation process. This thesis addressed the empirical research questions by employing a single case study approach. The case study was the Africa RISING Ethiopian Highlands Phase 1 (2011–2016) project. Both primary and secondary data from various sources were collected from September to December 2018, two years after the multilevel IPs were phased out. The primary data were collected using semi-structured questionnaires developed separately for farmers, project coordinators, and other stakeholders involved with the multilevel IPs. A total of 48 key informant interviews and ten focus group discussions were conducted. Secondary data of project documents, IP event (meetings, field days, and training) reports, and the published and grey literature research reports produced were used to analyse the innovation process and triangulate data. Data were transcribed and coded using NVivo software. A thematic analysis approach was used to analyse the data and address the three research questions identified under the overall research aim.

Chapters 2, 3 and 4 address the three empirical questions of the research. The findings show that both successes and challenges were observed in operationalising the AIS approach. The positive achievements of the multilevel IPs identified were the inclusivity of the diagnosis activities, the technical changes generated, and the improvements in collaboration between actors within the innovation process. The challenges faced by the multilevel IPs were identified as resulting from the limited attention given to market-oriented and institutional issues and were mainly related to weaknesses in ultimately fulfilling the demand articulation function. However, overall, the expected advantages of a multilevel IP structure were not fully realised.

The main insight from this study is that a multilevel structure is not in itself sufficient to address issues of stimulating institutional innovation, ensuring sustained innovation, and making sure innovations meet the needs of farmers. For this, possible strategies for better fulfilling this critical function of demand articulation are provided by a framework (Chapter 5) that aims to shift the focus from farm-level technological innovations to a broader view of innovation that encompasses the organisational and institutional elements of innovation based on systems thinking. The proposed strategy involves the need to view the whole value chain for the specific farm enterprise chosen by farmers as an integrated system. Improving the efficiency of the system should be the shared goal of the diverse and multilevel stakeholders who can address the interrelated value chain issues that farmers experience in order to increase the productivity of farmers’ livestock enterprises and enable the farmers to participate in the growing market opportunities for livestock products. The limitations and opportunities of the case study approach and further research areas are also indicated. The thesis draws key lessons from the case study.

Eggplant (Solanum melongena L.) is one of the horticultural vegetables that is widely distributed in Indonesia. It is just like other vegetables, and eggplant offers a variety of health benefits. Seaweed is one of a group of marine plants that containing many important minerals. Seaweed also contains a growth-promoting hormone. This research aims to study the effect of application of various types of local seaweed extracts on growth and yield of eggplant. The study was conducted using Randomized Block Design (RBD) which consist of 6 treatments: P0 = without fertilizer (control), P₁ = fertilizer NPK, P2 = Seaweed Cauelerpa sp, P₃ = Seaweed Sargassum sp, P₄ = Seaweed Kappaphycus alvarezii, P₅ = Seaweed Ulva sp. Each treatment is repeated 4 times to obtain 24 units of the experiment. The results of this research showed that the application of seaweed extracts significantly affected on growth and yield of eggplant plants (plant height, number of leaves, leaf area, fresh weight of plant, dry weight of plant, fruit fresh weight, fruit dry weight and chlorophyll content but did not show significant on first flowering appear, roots fresh weight and root dry weight. All seaweeds show a potential to replace the use of NPK in improving the growth and yield of eggplant.

The Western Australian sheep meat industry has been in steady decline for the past three decades, with sheep numbers in the state halving since 1990. There are many causes of this decline, but innovations in product and marketing have also presented new opportunities for the industry. In a single organisation case study, novel assessment methods were used to generate quantitative and qualitative data to measure supply chain relationship quality and its determining factors. Results indicated an imbalance between processor and producer perceptions of relationship quality, where processing staff recognised the potential for improvement from the current quality of relationships while producers were content in their relationships. Across several on-going innovations, evidence for cohesion of supply chain actors in the innovations' implementation was scarce. Results suggest that the processor's staff and producers are willing to improve supply chain relationships, but their action is constrained by opposing perceptions of supply chain performance. Improved communication channels and direct contact from the processor will see producers more satisfied and willing to increase commitment. Further, it is suggested that livestock agents will need to act in a manner beneficial to others in the supply chain to improve the quality of relationships with processors and producers. The processor proposes actions to achieve these ends, essentially by paying personalised attention to individual producers' needs.

Conservation Agriculture with Trees (CAWT) is promoted as a sustainable way to enhance farm productivity and address food insecurity in populous Sub-Saharan Africa. CAWT combines the three principles of Conservation Agriculture (CA), namely minimum soil disturbance, maximum soil cover, and crop rotation or association, intercropped with trees. For CAWT to deliver benefits in East Africa, it must be widely adopted by farmers. CAWT as a complex combination of practices requires effective agricultural advisory services (AAS) for promotion. There is little comparative evidence on utilised advisory models available in the region to inform the design of AAS for CAWT. This research took place in Machakos County, Kenya, under a CAWT promotion project, and assessed the performance of two participatory advisory models, Landcare and Farmer Field Schools, compared to the more traditional top-down Ministry of Agriculture (MOA) delivery model. To understand the advisory models performance, assessment criteria were used: inclusivity of men and women, efficiency in delivery, social networks for information sharing and collective action and improvements in understanding and uptake of practice change of CAWT. By understanding the studied advisory models, and building on their individual strengths, a pluralistic agricultural advisory system for scaling-out CAWT was outlined.
Data was collected from 292 farmer respondents, who were members of farmer groups under the three advisory models and exposed to CAWT training. Gender disaggregated data on the assessment criteria was collected and key informant interviews, personal observation and training reports added context to the findings. Data analysis included logistic regression, social network analysis, and descriptive statistics.
Research results found the participatory models improved farmers' practice of CA by 20 percent more than the traditional top-down MOA model, the effect of this reduced for FFS at the local sub-county level. Participatory models did not improve farmers' understanding or practice of agroforestry, or combined as CAWT above that of the MOA model however. Agroforestry practices promoted as part of CAWT, were not accepted by the farmer group members, with below 12 percent practicing. The participatory models, and the MOA Mwala site under the traditional model, enhanced social capital in terms of producing dense and connected social networks for information sharing amongst farmers, extension agents and organisations. All models promoted equal understanding and practice for men and women, but Landcare achieved greater empowerment of women in terms of establishing their prominent role in information networks. Participatory models were 31-51 percent more expensive to deliver than the traditional MOA model, due to the provision of meals to farmers and better remuneration of extension agents but took less of farmers' valuable time to deliver training.
To scale-out CAWT in Machakos County, and similar locations within Kenya and the wider East Africa, it is recommended that participatory models be used. While these models did not consistently perform better than the MOA model across the assessment criteria, they did deliver multiple and greater benefits. MOA model in Mwala Sub-county performed as well as the participatory models, and better than the other two MOA sites, in terms of social networks, CA practice and information access. Extension agents at this site were more facilitative and participatory than the other MOA sites, highlighting the importance of the extension agent in determining the delivery of an advisory model. A pluralistic AAS system, with government extension and non-government organisation (NGO) service providers is recommended to deliver participatory models. Pluralism builds on the strength of each provider. Government extension has greater reach and sustainability while NGOs have more experience in promoting social capital through participatory models and access to alternative resource streams. Government extension can utilise participatory models, as witnessed in MOA Mwala, provided extension agent capacity is built and NGOs would have an important role in this process.
In conclusion, findings from this research partly agree with the literature that participatory models perform better than top-down models to enhance the adoption of complex practices, provided the community is interested in the practices, which was not found for agroforestry in this study. Advisory model delivery is however variable as shown by MOA Mwala. Research findings highlight the following recommendations. Implementation of pluralistic AAS should include capacity building of extension agents in participatory models, building of bonding and bridging capital, focusing on empowerment of women and utilising opportunities to reduce cost such as through rotational funds and local facilitators. Future research is required on appropriate motivators for extension agents to support participatory models; social networks for transferring complex information and collective action; and trade-offs between participatory extension delivery and the higher costs of such delivery modes. Future investigation could take place as an action research, while simultaneously promoting CAWT through a pluralistic and participatory advisory system.

Poultry litter is rich in nitrogen (N) which is one of essential nutrients to support and enhance plant productivity. However, large quantities of the N are lost through volatilisation of ammonia (NH₃), and also through leaching of ammonium NH₄⁺) and nitrate (NO₃^-), when fresh poultry litter is applied to the soil. Also, during decomposition of poultry litter nitrous oxide (N₂O) and methane (CH₄), which are potent greenhouse gases (GHGs), are emitted. Composting of this nutrient rich product can still produce NH₃ which is a precursor for indirect N₂O emission, and also direct emissions of N₂O and CH₄ and possibly in greater quantity if the material is not kept well-aerated during composting. The loss of gaseous N decreases the fertilizer value of the final compost product.

Biochar, which is a carbon rich material produced by heating biomass with little or no oxygen, has inherent and emerging sorption properties that may give it capacity to reduce losses of N when co-composted with other organic amendments such as poultry litter. This study cocomposted poultry litter and sugar cane straw with two different biochars: greenwaste biochar (GWB) and poultry litter biochar (PLB), in two separate experiments. The experiments were conducted in large compost tumblers, to investigate the influence of biochar on N₂O, NH₃ and CH₄ emissions during composting, and retention of N in the final compost. The greenwaste biochar compost (GWBC) and poultry litter biochar compost (PLBC) produced from these experiments were used in a subsequent laboratory trial: GWBC, PLBC, PLB and poultry litter compost (PLC, nil biochar) were applied to soil as organic amendments to assess their influence on N₂O emissions and leaching of nitrate (NO₃^-), ammonium NH₄⁺) and dissolved organic carbon (DOC) from two different soils (Tenosol and Ferrosol) in a 63-day incubation experiment across three wetting and drying cycles. The final experiment employed a stable isotope (10 % ¹⁵N urea) method in a field trail in Ghana to investigate whether biochar and biochar-amended compost could improve fertilizer N uptake, reduce fertilizer N loss and improve fertilizer N use efficiency (FNUE), to increase maize yield. The PLB, PLBC and PLC were co-applied with ¹⁵N labelled urea and compared with a urea-only control (Control+U) in two different soil types (Ferric Acrisol) and (Ferric Lixisol).

In the first compost experiment, the GWBC decreased (P ≤ 0.05) cumulative NH₃ emissions per unit of initial dry mass by 56 % while PLBC decreased the NH₃ emissions by 38 % compared to the control (nil biochar). The GWBC and PLBC significantly decreased emissions of NH₃ per unit of initial total N in the amendments; by 65 % and 55 % respectively cf. control. The GWBC had the highest activities of beta-glucosidase and leucine aminopeptidase enzymes as well as the lowest DOC among the treatments. The concentration of NH4+ at the end of composting was higher in the GWBC than the PLBC. In the second composting experiment, The GWBC and PLBC emitted 65 - 75 % less N₂O cumulatively than the control expressed per unit initial total N. Furthermore, CH₄-C emission was significantly lower in the biochar treatment relative to the control only during a period of composting when oxygen was probably limited in the compost mixture (ie the period where there was no tumbling) More FeO and amine/NH₃ were found on surfaces and pores of the composted biochar compared to the uncomposted biochar, indicating a change in interaction of N functional groups with Fe-dominated minerals in biochar. When GWBC, PLBC, PLB and PLC were applied as organic amendments to soil in the incubation experiment, cumulatively N₂O emissions, which were highest when water filled pore space was between 0.70–0.85 across all the treatments, were significantly lower in the PLB and PLBC treatments compared to the PLC in both soils (Ferrosol and Tenosol). Compared to the control (unamended), all treatments had significantly lower N₂O emissions in the Ferrosol, whereas onlyPLB had lower N₂O emissions in the Tenosol. Cumulative emissions of CO2 were significantly higher in the GWBC and PLBC treatments than the PLB and the unamended control in both soil types. Leaching of NO₃^--N from the Ferrosol was greatest during the first wetting and drying cycle, while it was greatest in the third cycle in the Tenosol. Significantly more NH4+-N than NO₃^--N was leached from both amended soils. The total amount of NO₃^--N leached per unit of total N applied were 48 % and 71 % lower for PLB in the Ferrosol and Tenosol respectively compared to their controls. More DOC was leached from the PLC treatments in both soil types cf. PLB, PLBC and GWBC treatments (P < 0.05), thus suggesting that biochar, whether pure or co-composted, does stabilise labile organic C in the contrasting soils. In the field trial, the FNUE from the applied ¹⁵N-labelled urea was significantly higher in the PLBC+U (32 %) compared to 24 % and 20 % in the PLB+U and PLC+U in the Ferric Lixisol. The PLBC+U in the Ferric Lixisol had the higher (P > 0.05) N retained in soil (64 %) and lower N loss (4 %) compared with the PLC+U (31 % retained and 49 % loss). There was no significant difference in crop FNUE and fertilizer N recovery in soil between treatments in the Ferric Acrisol. The PLBC+U and PLB+U treatments significantly (P ≤ 0.05) increased maize yield compared to PLC+U in both soil types. Similarly, significant increase in the total C, total N, pH, and cation exchange capacity of the PLB+U, PLBC+U, compared to the PLC+U, at the end of the experiment was observed.

Based on the findings of this study, it was hypothesized that the intrinsic structural and sorption properties of biochar and the sorption properties that develop through interaction between biochar and organic compounds, decreased NH₃, N₂O and CH₄ emissions. These inherent and emerging sorption properties may have enhanced adsorption of N precursors like NH4+ and NO₃^- and prevented them from being nitrified or denitrified during composting and in soils when applied as amendments. Similarly, these processes were hypothesized to reduce leaching of inorganic N and labile C from soil, possibly facilitated by the co-composted biochar interacting with other organic amendments. Furthermore, higher crop FNUE in the Ferric Lixisol (a lighter textured soil) compared to the Ferric Acrisol (silty loam), was a result of biochar and cocomposted biochar (in biochar-amended compost) that increased N uptake by ameliorating soil constraints, particularly soil acidity, low P and low CEC. The findings from this thesis have demonstrated that co-composting biochar with poultry litter and straw decreased GHG and NH₃ emissions and increased retention of N, thus increasing its fertilizer value. This biochar-amended compost when applied to soil would be effective in decreasing emissions of N₂O and leaching of inorganic N and labile forms of C from contrasting soils, while increasing N retention, N uptake and lowering soil N loss, with implications for increased crop FNUE and yield while minimising adverse environmental impacts.

Introduction: This study is a review of secondary literature that has been synthesized to extract information and demonstrate the implementation and impact of community conversations (CCs) on gender aspects of social norms in livestock-based systems in Ethiopia.

Methods: The study used the phenomenological method of qualitative literature review to sketch the gender transformative approach to the delivery of knowledge products in a program on transforming the small ruminant value chain. The CC aimed at addressing gender-related norms in the division of labor, resource ownership, and handling practices of animals and their products previously identified, and those that emerged during the CC events across the study sites. A total of 1,517 community members (out of which 574 are women) took part in various CC events.

Results and discussion: The review shows that the gender-related norms addressed were in line with the identified constraining norms faced by women livestock keepers in the mixed and livestock-based systems. The CC approach adopted complied with the stages laid out in literature: identification of existing knowledge; imparting new knowledge; knowledge integration and application; and review, reflection, and re-planning. The process was inclusive and community-engaging, which possibly cultivated intrinsic motivation and ownership of the process. Changes in knowledge, attitudes, and practices at household, community, and institutional levels were identified. The conclusions include institutionalizing the gender transformative approach in the public agricultural extension system. This could be facilitated by the generation of robust objective evidence of impacts and guidance for subsequent scaling at local, regional, and national levels.

Free-range laying hens are perceived by consumers to live a more “natural” and “happier” life, with improved welfare compared to caged hens. However, the impact of free-range housing systems on bird health and welfare is poorly understood. Thus, the aim of this thesis was to provide evidence on how hens utilise the range and shed resources in an Australian free-range housing system, and examine the impact of this on bird health and behaviour. The research presented involved monitoring flock dynamics and measuring hen performance, with the aim of better understanding the nutrient requirements of free-range hens.

In order to quantify individual hen usage of the range and aviary system, a Radio Frequency Identification (RFID) system was custom built by the University of New England to track 18 000 hens throughout the shed, both in the aviary system and on the outdoor range, in a commercial free-range farm. This RFID system technique was validated, achieving a precision of 90.0%, accuracy of 87.7% and specificity of 86.4%. The data produced allowed for individual hen’s occupancy at various zones to be determined, including duration of time spent at each of the four locations. Flock body weight was also assessed, as an indicator of bird health status. According to individual hen range use, flock sub-populations were identified and production performance and health of these sub-populations was investigated; these sub-populations were classified as ‘stayers’ and ‘rangers’, identified as hens that either spent the majority of their time in the shed or on the outdoor range, respectively. The results showed that these sub-populations clearly have different behaviours at different ages, impacting their mortality, health and welfare. Hens that were ‘rangers’ during early lay (18-21 weeks of age) were 3 times more likely to survive and had 10% higher egg production during early lay compared to hens that preferred to stay in the shed, but there was no difference on overall production over the life of the flock. The effect of range use on egg quality and bone health was also investigated, but no statistically significant effects were identified.

In conclusion, this thesis demonstrates the successful application of modern tracking technology and machine learning to collect and utilise large data sets to accurately characterise behaviour, resource use, and resulting dynamics, of free-range hens. These methods provide powerful tools for evidence-based decision-making regarding housing design and management procedures, to achieve desired performance and welfare outcomes. One such advantage is that it may enable optimised use of feed resources to ensure the nutrient requirements of all sub-populations are achieved.

The 'power' of digital innovation within the Australian chicken meat sector is projected by many analyses to lie in digitally enabled advances surrounding traditional strengths of productive efficiency, consumer acceptance, and relatively low retail prices. The power also lies in variations to conventional models so as to innovate into value-added products, particularly those bearing information-related attributes such as traceability. This report characterises the nature of benefits available and the prerequisites and mechanisms for capturing them. However, there is considerable variation among stakeholders in the industry and each is motivated by contextually specific potential gains and unique capabilities in securing them.

This scoping study collects, evaluates and presents available information so as to map relevant literature, experience and knowledge to the field of digital transformation in the Australian chicken meat industry.

Community-based ecotourism (CBE) promotes conservation, sustainable tourism, community cohesion, and equitable benefit distribution. Our case study investigates the quality of community involvement in implementing the CBE framework within Cat Tien National Park, a major conservation reserve in Vietnam. Using qualitative methods, such as key informant interviews and participant observation, the study assesses the level of community participation in this particular ecotourism venture. Despite its collaborative design, the project's top-down implementation constrained local involvement and benefits. Challenges included power imbalances, capacity issues, and unfair distribution. These highlight the need for better stakeholder involvement, transparent governance, and genuine community engagement to improve CBE outcomes. To address these challenges, the paper recommends establishing community advisory boards, increasing support from government and private sectors, and integrating traditional knowledge into conservation. It emphasises the need for long-term commitment, culturally sensitive awareness campaigns, effective capacity-building, and transparent feedback to enhance community engagement and manage expectations.

Growth in population and income, as well as urbanisation, are contributing to the growing consumption of high-value foods in developing countries. However, public and private investments targeting high-value agricultural markets are constrained by limited information on the quality dimensions of the market, the nature of traditional retail formats, and consumer segmentation. This paper presents a simple and appropriate methodology to provide such information, and applies it in Tanzania to animal-sourced foods. It features a rapid survey, which is then aligned with nationally representative survey data. The results show that Tanzanian consumers demand, and are anticipated to continue demanding, relatively good-quality animal products but in rather low-valued product forms. Consumer segments are differentiated by level of wealth and by choice of retail format and retail product form, rather than by quality per se.

The livestock sector is vital to Botswana's rural economy comprising nearly two-thirds to the national agricultural sector. The goal of this research is to measure competitiveness and identify the factors affecting it, so as to advocate change in Botswana's smallholder livestock systems. The study examines a cross section of farm-level data gathered from 556 randomly selected livestock producers to investigate the profit efficiency and competitiveness of three farm size categories of small holder livestock farmers. Results found a considerable capacity to improve beef profitability. Scale effects on profit efficiency are generally positive, but the results indicate a number of interactions between scale and other variables such as off-farm income and the use of credit. Policy analysis and commercial decisions using models that assume efficiency are therefore presenting a misleading picture, particularly on the elusive subject of Botswana smallholders' beef supply response.

Rice-based cropping systems (RBCS) cover the majority of cultivated land in Bangladesh and are the country's primary source of food security. To bolster food security, cropping intensity has increased by 192% in the last 30 years. Concerns have been raised about the sustainability of such cropping increases, particularly for soil pro-ductivity and resilience, with many areas reporting low soil organic carbon (SOC). The research assessed the levels of SOC, total nitrogen (TN) and soil pH in RBCS to identify relative importance of the land resource, cropping and management settings on these soil properties and to determine options for sustainable land use intensification. Soil samples (0–30 cm) were collected following stratified random design from a range of RBCS and analyzed for SOC, TN and soil pH. These soil properties were interpreted against previously developed farming system typology of Soil Carbon Improvement Likelihood (SCIL) and the legacy soil datasets. SOC was recorded higher in the stop-go triple cropping (12.00–16.33 g/kg) compared to the triple and double cropping intensities (6.90–8.30 g/kg). The crop-diversified and mustard-rice cropping systems of High SCIL, where there is crop rotational diversity and high residue retention, recorded a higher SOC. However these systems were also located on inherently fertile soil (Floodplain medium highland) compared to the less diverse cropping systems (wheat-rice, veg.-rice and rice-rice) of Medium and Low SCIL. The wheat-rice system had the lowest SOC (5.46 g/ kg), which is considered to be a consequence of low crop residue retention and reduced periods of inundation in highland on the Piedmont plain or Terrace. However, the build up of SOC and TN was linked to soil acidification associated with altered fertilizer regime and crop residue removal. Cropping intensity, and in particular, the associated cropping systems and management, were determinants of SOC, depending on which land resource setting and cropping systems were practiced by the smallholders. The types of cropping systems and management options in land resource settings were identified that have the potential for sustainable land use intensification. The implications would be to ensure these cropping systems are conserved, and trade offs contemplated to meet the rising food demand and carbon sequestration goals to counteract smallholder vulnerability to climate change in Bangladesh and South Asian countries.

This thesis examines the methods to improve the productivity of a dual-purpose native chicken breed in Thailand. Five generations of body weights and egg production data on Lueng Hang Kao Kabinburi (LHKK) chickens were used for estimation of genetic parameters in chapters 3 and 4. Traits considered were body weights, measured at four-weekly intervals from hatch to 24 weeks of age (BW1D, BW4, BW8, BW12, BW16, BW20, and BW24), body weight at first egg (BWFE), age at first egg (AFE), egg weight at first egg (EWFE), and egg number (EN).There were 11,588 chickens from 486 cocks and 1,461 hens that had records for growth and egg production traits. Relationships between growth rate and egg production traits were also explored. The level of inbreeding and its effect on growth and egg production were explored. In chapter 5, hatchability (HAT), rate of lay (RL), average daily gain (ADG), and survival rate (SUR) were identified as economically important traits and were used in a selection index to optimize the genetic response to selection. Finally, in chapter 6, population sizes and mating ratios were explored to optimize the genetic response in HAT, RL, ADG and SUR while minimizing the rate of inbreeding in the nucleus flock of LHKK chickens by simulating 20 generations of chickens for recurrent selection.

Univariate and bivariate analysis were used to estimate genetic parameters in body weight and egg production traits. Fixed effects of year and hatch within year were significant for all traits and sex was significant for all body weight traits, except for BWFE. The direct additive genetic effect was significant for all traits and the maternal genetic effect was significant only for growth traits, except BWFE. The maternal permanent environmental effect was significant for all growth traits, except for BW24 and BWFE. The estimates of heritability for direct additive genetic effect ranged from 0.10 to 0.47 for body weight traits and ranged from 0.15 to 0.16 for egg production traits. High positive genetic correlations were estimated between all traits, except for negative genetic correlations between EN and other traits. Inbreeding effect on growth and egg production traits was not significant, except for BW1D, where BW1D reduced by 0.09 g when the rate of inbreeding increased by 1% per generation.

Univariate random regression model was used to estimate genetic parameters for body weight traits along the growth trajectory from BW1D to BW24. A quadratic Legendre polynomial was identified as the best model to estimate variance structure for all random effects fitting heterogeneous residual variances based on six growth periods. Heritability estimates ranged from 0.34 to 0.54 and 0.04 to 0.06 for direct additive and maternal genetic effects, respectively. Estimated variance ratios ranged from 0.19 to 0.48 and 0.10 to 0.12 for direct and maternal permanent environmental effects, respectively. All genetic correlations between body weight traits were high and positive.

Genetic relationships between growth rates, measured at four-weekly intervals, and AFE and EWFE were estimated using bivariate analysis. Estimated heritabilities for growth rates ranged from 0.06 to 0.28. Estimated heritabilities for AFE and EWFW were 0.24 and 0.16, respectively. Genetic correlations between growth rates and AFE ranged from -0.22 to 0.02, and between growth rate and EWFE ranged from -0.05 to 0.40. The result suggested that selecting chicken with a high growth rate at an early growth period (at 28 days of age) would improve the body weight and egg weight at sexual maturity while reducing the age at sexual maturity.

Breeding strategies to improve the meat and egg production of the LHKK chickens under intensive (IPS) and extensive production system (EPS) were explored. A bioeconomic model was developed to calculate economic weights for HAT, RL, ADG and SUR. Estimated economic weights and the response to selection showed that LHKK chicken production was economically viable under the IPS and the EPS in Thailand. Annual economic return per hen in the EPS (621THB) was higher than the annual economic return per hen in the IPS (132THB) due to the lower cost of production under the EPS than the IPS. Calculated combined economic weights from the IPS and the EPS were 21.01THB for HAT, 56.52THB for RL, 106.52THB for ADG, and 15.76THB for SUR. The estimated relative economic weights showed that RL was the most important economic trait in LHKK chicken production. Decreased feed price and increased fattening chicken price is expected to increase the monetary return from the native chicken farms. Using the multi-trait selection index resulted in predicted responses of 0.97% in HAT, 2.41% in RL, 1.38g in ADG and 0.73% in SUR. Thus, implementing a single breeding objective strategy in the nucleus flock of the LHKK chickens will improve the productivity under both IPS and EPS.

A stochastic simulation using an optimal contribution selection (OCS) approach with a target of 25º for mate selection was used to minimize the level of inbreeding and maximize genetic gain in LHKK nucleus flock. The level of inbreeding and genetic gain for a range of population sizes and mating ratios were compared after 20 generations of recurrent selection. The predicted level of inbreeding indicated that increasing the population size by 30% from the current population size would reduce the level of inbreeding in LHKK flock by around 1% per generation. Reducing the nucleus size by 30%, in comparison to the current nucleus size, will increase the level of inbreeding by 1.55% per generation. The highest level of inbreeding was found in the higher mating ratios of one cock to floating hens (one to 10 hens) and the lowest level of inbreeding was found in the lowest mating ratio of one cock to three hens. The predicted genetic responses obtained across the four mating ratios were not significantly different to each other.

In summary, this study found that the growth and egg production traits in LHKK chicken are heritable and also have high genetic correlations between them. Therefore, both meat and egg production of LHKK chickens can be improved by implementing a multiple traits selection strategy. Furthermore, implementing a common selection strategy in the nucleus flock of LHKK chickens is expected to increase the monetary return under an intensive and extensive production system in Thailand. However, the effects of using a system specific selection strategy for IPS and EPS on the profitability under each production system need to be explored. Increasing the current nucleus flock size and reducing the mating ratio will fulfil the main objective of the current LHKK breeding program by further improving the meat and egg production, while maintaining the breed characteristics of LHKK chickens.

One of the predisposing factors for the onset of necrotic enteritis (NE) in poultry is indigestible nutrients or nutrient imbalance. Poorly digested diets lead to the accumulation of undigested nutrients in the lower gut feeding pathogenic bacteria or create favorable conditions (high pH) that favour their proliferation. Meat and bone meal (MBM) and high dietary calcium (Ca) are examples of such dietary factors that might favor the overgrowth of enteric pathogenic bacteria.

Three experiments were conducted in this project employing a 2 × 2 × 2 factorial arrangement of treatments. The factors were: Exp. 1, MBM (no or yes), AB (no or yes, zinc bacitracin + salinomycin) and phytase level (500 or 1500 FTU/kg; both using 500 matrix recommendations); Exp 2, NE challenge (no or yes), Ca level (0.6 or 1.0% starter, 0.5 or 0.9% grower, 0.4 or 0.8% finisher with the same level of P in each phase of the study), phytase (500 or 1500 FTU/kg both using 500 matrix recommendations) and Exp. 3, NE challenge (no or yes), (500 or 5000 FTU/kg both using 500 matrix recommendations) and MBM (as-received, AR or over-processed, OP). The diets used in all the experiments were based on wheat, SBM and canola meal. All the birds in Exp. 1 were challenged and only half of the birds in exp 2 and 3 were challenged. The challenge birds were inoculated with Eimeria spp. on d 9, and Clostridium perfringens (C. perfringens) strain EHE-NE18 on d 14 and 15. The effects of the factors/treatments were measured as changes in performance, nutrient digestibility, phytic acid hydrolysis, bone mineralization, haematology, intestinal morphology, jejunal gene expression and welfare (hock burns and litter quality).

Chapter 2 presents a review of the possibility of dietary MBM and excessive dietary Ca to exacerbate the outcome of NE in broiler chickens.

Chapter 3 examines the influence of MBM, phytase and antibiotics on broiler chickens challenged with subclinical NE as measured by growth performance, intestinal pH, apparent ileal digestibility, caecal microbiota and tibial mineralization. The results revealed that on d 21 (post-challenge), birds fed MBM had reduced weight gain (WG; P < 0.05) relative to without MBM. The WG on d 14 (P < 0.001) and d 21 (P < 0.001), and FCR on d 21 (P < 0.001) and d 42 (P < 0.01) indicated positive effects of high phytase on bird performance in the presence of AB. On d 42, high phytase increased WG with AB (P < 0.01), relative to the birds without AB in the presence of MBM. There was a notable reduction in Ca and P digestibility in birds fed MBM-free diets and a low phytase level on d 16 (P < 0.01), but with the high phytase level, Ca and P digestibility was not influenced by MBM. Thus, it was concluded that in NE challenged birds, high phytase has a beneficial effect on leg health and mineral utilization, to the extent that it can replace MBM and has beneficial effects on bird performance in the presence of AB.

Chapter 4 examines the influence of MBM, phytase and antibiotics on broiler chickens challenged with subclinical NE as measured by intestinal permeability, organ weights, haematology, intestinal morphology and jejunal gene expression. The results indicated that lymphocyte counts were lower (P < 0.01) with MBM and AB compared to MBM without AB. Villi length was increased (P < 0.05) with high phytase and no AB compared to AB. Inclusion of MBM increased blood fluorescein isothiocyanate dextran (FICT-d; P < 0.05) concentration whereas AB decreased it (P < 0.001). Antibiotics increased red blood cells (RBC; P < 0.05), haemoglobin, (Hgb; P < 0.05) and packed cell volume (PCV; P < 0.05) and expression of Ca-binding protein (CALB1; P < 0.05). Overall, it was demonstrated that dietary MBM has a detrimental effect on the gut health of broilers, but the effect may be reduced by using AB.

Chapter 5 evaluated the effect of OP MBM and phytase effects on broilers challenged with subclinical NE as measured by performance, intestinal lesions and pH, bacterial counts and apparent ileal digestibility. The results indicated that challenged birds fed OP MBM had decreased BW (P < 0.05) and FI (P < 0.05) at d 14, increased FCR (P < 0.01) at d 21 and decreased BW (P < 0.05) and FI (P < 0.05) at d 28. Birds fed low phytase had increased livability (P < 0.05) at d 42. The challenge increased the prevalence and severity of NE induced lesions in the jejunum (P < 0.001) and ileum (P < 0.01). The birds fed OP MBM had decreased pH in the jejunum (P < 0.05) and ileum (P < 0.05) at d 16. High phytase increased apparent ileal digestibility of Ca (P < 0.05) and P (P < 0.001). The challenge increased the counts of Lactobacillus spp. (P < 0.01) and C. perfringens (P < 0.001) at d 16. It was concluded that the supplementation of diets with high phytase reduces the negative impact on performance from OP MBM during NE as a result of increased nutrient digestibility.

Chapter 6 assessed the effect of OP MBM and phytase effects on broilers challenged with subclinical NE as measured by changes in inositol phosphate esters hydrolysis, intestinal permeability, haematology, jejunal gene expression and intestinal morphology. The result revealed that birds fed low phytase had increased inositol penta-phosphate (IP5; P < 0.05) and inositol hexaphosphate (IP6; P < 0.05) in unchallenged birds only when diets contained OP MBM. Challenge with NE increased intestinal permeability as measured by serum FITC-d (P < 0.001), increased white blood cells (WBC, P < 0.001), decreased mean corpuscular volume (MCV; P < 0.001) and mean corpuscular hemoglobin (MCH; P < 0.05), and decreased crypt depth to villi length ratio (P < 0.05). The OP MBM reduced the villi: crypt ratio (P < 0.05). Only in unchallenged birds fed OP MBM did high phytase reduce MUC2 expression (P < 0.05). It was concluded that NE had a negative impact on the gut and haematology of broilers, but its effect on phytate hydrolysis was minimal.

Chapter 7 evaluated the effect of OP MBM and phytase effects on broilers challenged with subclinical NE as measured by changes in litter quality and bone mineralization. The study showed that at d 16, challenged birds had lower toe ash (P < 0.01), femur ash (P < 0.001), tibia ash (P < 0.001) and tibial breaking strength (BS) (P < 0.001) than unchallenged birds. At d 16, only challenged birds fed high phytase and OP MBM had higher toe Mn than those fed low phytase and AR MBM. At d 16, tibial Ca (P < 0.05) and P (P < 0.05) were lower in the challenged whereas the femur K (P < 0.001), Mn (P < 0.01) and Na (P < 0.001) were higher in the challenged at d 16. At d 42, challenged birds had higher litter DM (P = 0.058) and fewer hock burns than those unchallenged (P < 0.05). It was concluded that NE impaired bone traits while high phytase and OP MBM increased bone mineral contents.

Chapter 8 investigated the interactive effect of two dietary calcium and phytase levels on broilers challenged with subclinical NE as measured by changes in broiler performance, gut lesions and pH, bacterial counts, and apparent ileal digestibility. The results showed that gain was higher in birds fed high phytase on d 14 (P < 0.01), d 21 (P < 0.01), d 28 (P < 0.01) and d 35 (P < 0.01). Birds fed high phytase had greater livability on d 0-21 (P < 0.01). Calcium was more digestible in high Ca diets on d 16 and a NE × Ca interaction showed this effect to be more pronounced in unchallenged compared to challenged birds. A challenge × Ca interaction was observed for apparent ileal digestibility (AID) of CP (P < 0.05) indicating a lower AID of CP in challenged birds fed high Ca. The challenge decreased AID of Ca (P < 0.01). Calcium had no impact on C. perfringens count, but it decreased Lactobacillus (P < 0.05) and Bifidobacteria (P < 0.05) populations in the caeca. Thus, high Ca in the presence of phytase was beneficial for growth except that Ca created a condition in the gut where the incidence could have been worse if the challenge was clinical.

Chapter 9 investigated the interactive effect of two dietary calcium and phytase levels on broilers challenged with subclinical NE as measured by gut permeability, phytate esters degradation, jejunal gene expression, and intestinal morphology. The results showed that the inositol triphosphate (IP3; P < 0.01) and inositol tetra-phosphate (IP4; P < 0.05) concentrations were similar for both doses of phytase in the presence of low Ca, but with high Ca both increased significantly but to a greater extent when the high dose of phytase was used. A phytase × Ca interaction was detected for vitamin D receptor (VDR; P < 0.05) expression where bird fed low phytase and low Ca recorded the highest expression of VDR, all other treatments being equivalent. Challenge birds had higher FITC-d (P < 0.05) in blood compared to unchallenged birds. Thus, high Ca and high phytase, whilst not the best for IP6 destruction, did not lead to huge reductions in indicators of gut health.

Chapter 10 investigated the interactive effect of two dietary calcium and phytase levels on broilers challenged with subclinical NE as measured by changes in serum calcium and phosphorus, and bone mineralization. The challenge decreased serum (P < 0.05) Ca⁺ in birds regardless of dietary Ca level (d 16). Tibial BS (d 16) in challenge birds was far greater (P < 0.05) in the high Ca diet compared with low. Femur ash (d 16) in challenged birds was increased due to the phytase (P < 0.05). The challenge decreased (P < 0.05) the BS of femur and tibia at d 16 and 29. Birds on high dietary Ca had lower tibial Mg (P < 0.001), Na (P < 0.001) and Zn (P < 0.05) concentrations (d 29). Altogether, high dietary Ca and phytase improved bone mineralization.

Chapter 11 examined volatile basic nitrogen measurement in the caecal digesta of broiler from the 3 experiments using a Berthelot reaction in automated Skalar® instrumentation. The results demonstrated that an increase (P < 0.05) in caecal NH₃ as a result of feeding MBM (Exp. 1) or high dietary Ca (Exp. 2) with a corresponding increase in pH. In Exp. 3, birds challenged with NE had lower caecal NH₃ and lower pH on d 16 but not d 29 compared to unchallenged controls. It was concluded that the Berthelot method using Skalar instrumentation equipment is suitable to measure the concentration of volatile nitrogen as NH₃ in caecal contents and other digesta of chickens.

Overall, it was concluded that MBM is a potential predisposing factor for the onset of NE while the benefit from feeding high phytase in a MBM-based diet is only realized only in the presence of antibiotics. Also, overprocessing of MBM by way of heating beyond the existing industry practice increases the incidence of NE and impairs growth performance. Finally, high phytase is only beneficial to the growth performance of broilers only in the presence of low dietary Ca and high Ca promotes a gut environment that could increase the outcome of NE.

Digital agriculture has attracted plenty of excitement in recent years from investors – close to USD30B a year so far and increasing, pandemic notwithstanding. The vision of drones zooming over Australian rural landscapes to detect crop nutrition status or of robots tending vertical farms make a good story. And though narratives are powerful influencers for change as pointed out by Nobel Laureate Robert Shilleri, many are built on uncertain foundations.

We, too, like these ideas and have no doubt that digital technology will ultimately deliver major change to Australian agriculture. But what will this change look like to Aussie farmers, and how can they meaningfully engage? In the absence of concrete analysis, narratives can evaporate and leave people disillusioned, creating a problem for those doggedly pursuing authentic progress.

Agriculture, we know, has enormous potential for productive change through digital technology. But clarity is needed to explain how change is likely to occur, what drives and what obstructs change, given the peculiarities of agriculture and the array of factors to consider. Here we attempt to demystify the process of digitisation for Australian agriculture to establish a solid basis for expectations.

We do so by:

Defining the potential for digital agriculture globally as food systems respond to growing demand; Explaining common causes of failure; Identifying the different pathways to success - how they work and how they can be realised in Australian agriculture; and Finally, we focus on what farmers can expect from these changes, and what they and their partners need to do to lever the power of digital for sustainable growth..