Organic production in the hills and uplands (OF0319)

It is Government policy to provide a framework in which organic farming can develop, promoting more sustainable and environmentally sound systems of livestock production. Scientific information is required on the development, performance and limitations of organic systems, to facilitate informed decision-making and to aid policy formulation. Using the established organic unit at Redesdale, the overall objective of this project was to evaluate and demonstrate the long-term potential of organic livestock production in the hills and uplands. The experiment was a systems study sited on one discrete farm unit covering 518 ha. Approximately 400 ha had been put into conversion in 1991, so that the experimental period (2002 - 2005) represented years 9 to 12 years of full organic production. Approximately 600 Scottish Blackface ewes were involved in the study, in four self-replacing flocks. At the start of conversion, one original heft (Dargues Dipper) was split to form two sub-hefts of equal stock carrying capacity. One sub-heft (Organic Dipper) was converted to organic production, while the second (Conventional Dipper) continued to be managed conventionally. The two other hefts (Cairn and Burnhead) were both converted to organic production. Beef production was based on spring calving suckler cows, managed in three sub-herds - two a direct comparison of organic and conventionally managed Angus cross cows put to a continental sire; the third consisting of organically managed Angus cows put to an Angus sire. Grassland management was based on a modified ‘Two Pasture’ hill system, integrating native hill, improved hill and inbye land for beef and sheep production. On the native hill, detailed long-term monitoring of vegetation change showed that botanical composition was more affected by previous and current stocking levels, and events such as heather beetle infestation, than by organic and or conventional management. On improved hill land, the underlying trend was regression to rush pasture, leading to reduced productivity on both organic and conventionally managed areas. On the more intensively managed inbye fields, soil fertility levels were adequately maintained on the organic areas, which received only farmyard manure and slurries. Soil pH was more stable than on conventional fields, which received soluable nitrogen fertiliser. Organic inbye fields were sown predominately with short term leys, based on Italian ryegrass and Red or Alsike clover, to provide greater competition for weeds. Production levels were approximately 70% that of fertilised conventional fields. Self sufficiency in winter forage averaged 107% and 93% for the organic and conventional livestock (both sheep and cattle enterprises) respectively. Established infestations of docks production proved difficult to control. Historically, the greatest success was obtained where dock numbers were sufficiently low to enable the plants to be removed manually, or semi-mechanically using a tractor/digger. Data collected as an observation study suggested that for heavy infestations a fallow period and grazing by pigs could have good potential for dock control. Consistent with earlier the phases of the study, sheep production levels were higher in the conventionally managed sheep. Organically managed ewes were significantly lighter and had lower body condition scores at most stages of the production cycle. Average lamb rearing percentages over the three years of the study were 124, 108,108 and 111 for Conventional Dipper, Organic Dipper, Cairn and Burnhead flocks respectively. Average lamb weaning weights (kg) were 31.8, 29.5, 31.3 and 32.9 respectively. Of the total crop, 65% of Conventional Dipper lambs were sold finished at a mean liveweight of 38.1 kg, returning an average of £40.03 (£1.05/kg). The balance (35%) were ewe lambs retained within the flock or sold for breeding. Depending on the flock, the majority of the organic lamb crop (55%-61%) were sold after weaning as stores for further finishing, at a price of approximately £1.15 per kg liveweight. Store hill lambs performed well finishing on an organic lowland farm, returning typical carcass weights of 18.5 kg and a mean sale date of mid-March. An arrangement was entered into to spread the financial risk, sharing the feeders margin between the store lamb producer and lowland finisher. This could be a useful model for wider application, between different farmers or regions with complementary resources. Across all four flocks, the three year average for ewe and hogg mortality was less than 5%. Lamb mortality averaged less than 10%, which compares well with quoted industry figures of 15%-20%. Parasite burdens were low and anthelmintic input was limited to a few individual lambs. No adverse effects were recorded as a result of the long-term withdrawal of clostridial and pasteurella vaccination from one of the three organic flocks (Cairn). Lower levels of performance in the organic flocks could be a multi-component effect of reduced forage availability, lower veterinary inputs, higher levels of subclinical disease etc. However, the most likely factor was the difference in how the improved hill and inbye land was managed under an alternate grazing regime, which allows access by sheep to only half the area of improved hill in any given year. There was little difference in the physical performance of directly comparable organic and conventional sub-herds producing continental cross calves. Conception rates were consistently high, averaging 94%. Calf weaning weights (kg) averaged 292, 297 and 298 for conventional halfbred, organic halfbred and organic Angus sub-herds respectively. Prices achieved (p/kg live weight) for store prices cattle were 102, 127 and 133 respectively. Despite higher prices for organic cattle sold as stores, carcass data from animals sold finished indicated poorer conformation and higher levels of fatness in Angus sired calves. Gross returns were £683 and £648 for continental and Angus calves respectively, representing a difference of £0.10/kg carcass weight (£2.24 Vs £2.34). The main technical issue associated with the organic suckler herd was ensuring an adequate supply of conserved fodder for a 200-day winter. Disease challenges were low and the only veterinary treatment given on a herd basis was a single treatment for lice during the winter period. Average gross margins (£/ewe) before forage costs were £56, £44, £46 and £49 for Conventional Dipper, Organic Dipper, Cairn and Burnhead flocks respectively. Whole flock gross margins averaged £7635, £4609, £5561 and £4315. Lower performance in the organic flocks resulted from a combination of lower sheep numbers, reduced lambing percentages, and the sale of store rather than finished animals. Countryside Stewardship Scheme payments could potentially have increased gross margin in the Burnhead flock to £7915. Gross margins (£/cow), before forage costs, for rearing and finishing enterprises combined were £755, £636 and £527 for conventional halfbred, organic halfbred and organic Angus sub-herds respectively. Forage costs (£/adjusted hectare) averaged £11 and £21 for organic and conventional sub-units respectively. The biggest single contributor to gross margin was stocking rate, which for the organic unit as a whole, was 54% that of the conventional (1.3 LU/adjusted ha Vs 0.7 LU/adjusted ha). For sheep and cattle enterprises combined, gross margins per Livestock Unit (LU), including forage costs, were £451 and £479 for conventional and organic sub-units respectively. The organic unit as a whole returned a gross margin per adjusted hectare 44% less than the conventional (£590 Vs £335). It could be suggested that in reducing stocking rate in pursuit of environmental gain, and adjusting management for better parasite control, the organic system at Redesdale has had to carry a disproportionate financial burden. To offset these effects would require an improvement in output, for example retaining a greater proportion of organic animals for finishing, or entry into an agri-environmental scheme. The period of the study coincides with the last three years of subsidy payments based primarily on the numbers of livestock carried. Historically, stocking rates have been a prime determinant of profitability when measured on a per hectare basis. Under organic management it was not possible to support sheep numbers at previous levels and maintain the same level of individual performance. The advent of support based on Single Farm Payment, further devolves stocking rate from overall profitability. More farmers may be tempted to convert, given that the opportunity cost of conversion is reduced. Decisions will be driven more by the relative strength of the organic market, technical or attitudinal constraints such as feeding 100% organically produced diets, and relative impacts on overall fixed costs. The case for organic farming conferring environmental benefit is clearer in lowland situations than in the hills. In theory, the difference between organic and conventional systems should be less stark under less intensive production prevalent in the hills and uplands. As yet, little has been done to determine the extent to which organic and conventional farmers have adopted practices with positive or negative impact on biodiversity or the agri-environment. Much depends on the attitude of the individual landowner. From a survey conducted by ADAS in Wales, the greatest benefits tend to occur where an organic farm is also participating in another agri-environmental scheme. The extent to which organic, and evolving conventional, systems complement or conflict with cross compliance or Water Framework Directive requirements has yet to be determined. At Redesdale, long-term studies of vegetation change on the native hill, showed a continuing decline in heather cover at the higher stocking rates. Where stocking rates were reduced significantly to accommodate a more balanced organic system there were indications of a positive, albeit slow response in botanical composition. Key to this is the ability to manage moorland in a more proactive way, and to have cattle available to graze Molinia and Nardus. This complementary effect of cattle not only controls the competitive effects of these grassy species with heather, but as demonstrated in other research projects, also benefits sheep performance. If the economics of cattle production becomes very adverse organic farmers may be forced to reduce cattle numbers, which could make some sheep-dominated systems less sustainable. The results indicate that for many hill and upland units, converting to an organic system is not likely to be a matter of minimal changes to existing management. In particular, stocking rate and balance of sheep and cattle at the start of conversion will have a major impact on the management required to achieve acceptable levels of animal performance, financial performance, input reduction and environmental gain. Recommendations were made for further research in the following areas:- Current behaviours and management practices for organic and conventional farmers; the interface of organic farming practice, and that of other agri-environmental schemes; environmental impact at the whole farm, or aggregated farm level; practices to enhance environmental benefit which can be used more widely on organic farms; control of weeds (rushes, thistles, bracken and docks); tightening regulations on non-organic feed allowances; internal and external parasite control; nutrient budgeting; wider cropping options for energy, protein and mineral nutrition; the potential to exploit co-operative effort to overcome technical issues and limitations, and increase environmental benefit

Control of internal parasites in organic livestock without the use of pharmaceutical anthelminthics

Organic systems seek to reduce reliance on external inputs, and develop sustainable methods of production which balance output with high standards of animal welfare. The standards for organic production emphasise preventive control strategies based on grazing management, appropriate breeding and good nutrition. The ultimate goal is to eliminate dependence on anti-parasitic drugs, however this is rarely achieved in practice. The overall objective of this research was to develop organic farming systems, which do not rely on pharmaceutical control of roundworm parasites. Focussing on management and nutrition, the approach was to combine on-farm epidemiological studies, with replicated experiments, in order to develop and demonstrate better systems of control applicable to UK organic farms. The project was a collaborative study involving ADAS, Institute of Rural Science (IRS), Moredun Research Institute (MRI) and Scottish Agriculture Colleges (SAC). Specific objectives: 1. To study the epidemiology of parasitic gastro-enteritis (PGE) on selected 'focus' farms, representing a range of organic systems 2. To quantify the effect of dietary manipulation, novel crops, and drenching with tannins, on the development of PGE in organic sheep and cattle systems 3. To evaluate the role of crop type and pasture larval ecology on the development of PGE 4. To develop the application of alternative approaches on 'focus' farms, under best management practice 5. To ensure effective technology transfer Five commercial organic farms, reflecting a range of production systems (specialist hill sheep, upland beef and sheep, lowland specialist sheep, specialist dairying, and lowland mixed arable / livestock) were selected for detailed epidemiological study. The aim was to assess the level and pattern of parasite challenge, critical points for disease control, and the degree of success achieved with current management practices. The study combined the use of standard epidemiological techniques, with close collaboration of the researchers, participating farmers and their veterinary advisers. Comprehensive epidemiological data were collected over two contrasting seasons (2002 and 2003). Without recourse to routine anthelmintic, control was generally underpinned by grazing management, within the constraints of land/crop resources and diversity of enterprises available for each farm. Role of nutrition: Previous studies, using tightly controlled nutritional protocols and a known parasite challenge, developed a nutritional hypothesis for understanding nutritional influences on the host response to parasites. A replicated experiment was set up to test whether this framework could be extended to organically managed ewes carrying a mixed naturally-acquired infection. Novel crops: A series of experiments were undertaken to determine the potential of several novel crops for parasite control. Parasite pasture ecology: Nematode larvae populations have also been shown to differ between herbage species, potentially due to differences in crop morphology or microclimate beneath the sward (which may affect larval development and survival, or the number of coprophagous or nematophagous organisms at soil level). Several small plot and pot experiments were undertaken to assess the effect of crop type on larval survival, rates of faecal degradation, and soil dwelling invertebrates. Overall, the results from this study indicate that with sufficient diversity of cropping and stocking, it is possible to virtually eliminate anthelmintic usage. However, many farms still face significant difficulties, particularly those systems dominated by sheep. The extent to which control can be achieved by management alone, depends on the farming system, with the greatest opportunity for control in the more mixed, or very extensive production systems. Many of the issues faced by the organic sector are increasingly relevant to conventional farmers where anthelmintic resistance is becoming increasingly prevalent. More integrated strategies are required, not only for organic producers, but also to prolong the life of drenches currently used in conventional farming. Practical recommendations have been derived from this research, and promoted to organic and conventional farmers, based around key messages of system planning, parasite monitoring and maintaining biosecurity

Optimising the production and utilisation of forage for organic livestock (CTE0202)

On most organic farms in the UK, forages are fundamental to the application of organic farming practices, particularly where dairy cattle, beef cattle and/or sheep are the major enterprises. Methods used for the production, conservation and utilisation of these forage resources have a major influence on the productivity, efficiency and overall sustainability of organic farms. Forage management and utilisation also have a pivotal role in the maintenance of animal health and in the minimisation of environmental impacts associated with livestock farming. Specific objectives: 1. Extrapolating from published data, to review the requirements for energy and protein across the production cycle for organic milk, beef, lamb, pig and poultry production. 2. To predict the likelihood of meeting all or a minimum proportion of these requirements from a range of organically produced forages. 3. To examine the potential to adjust management or production system to achieve a better balance of nutrient supply and demand 4. To consider likely contribution from alternative forages, and protein sources, as home-grown feeds 5. To assess likely effects on animal health and product quality 6. To develop a database model to predict the potential output and benefits for organic farmers of implementing different options and strategies for forage production and utilisation 7. To determine the environmental losses and gains at each stage of production and utilisation 8. To provide specific guidelines for use by farmers, advisers and policymakers to maximise efficiency in the production and utilisation of forages within a range of organic livestock production systems. Overall, this body of work has indicated that a number of gaps in current knowledge exist such as: the particular suitability of diverse plants and animal genotypes for forage-based organic systems, methods for determining the nutritive value of organically produced forages, trace element nutrition of organic livestock and specific weed and pest control measures in organic crop production. Further dissemination of the outputs from this study, drawn from the five separate work packages in which the work was conducted, will help underpin the sustainability of the organic sector

Finishing store lambs from organic hill and upland farms OF0119

1. The aim of this study was to assess the economics and constraints associated with home finishing lambs on a range of organic hill and upland farms in England and Wales, and to evaluate the potential for further finishing on registered farms in the lowlands. 2. The current state of the organic sheep sector is briefly reviewed. This identifies problems of scale, limited premia and uneveness of supply as limiting factors to more rapid development of the market and associated production systems. 3. To quanitfy the effect of organic management on financial performance, hill and upland farms were classified under four typical systems, depending on the degree of intensification. 4. Without a sizeable area of improved ground, to which fertiliser and other inputs could have been applied conventionally, flocks based on high hill or marginal hill systems were least affected by switching to organic management. Flock Gross Margin on the marginal hill declined by approximately 7%. 5. On more intensive farms, typified by Welsh hill or upland farming systems, there is greater potential to finish lambs at higher stocking rates under conventional management, and the consequences of changing to organic management are greatly increased. Assuming a 10% premium for fnished organic lambs, deviating from convetional practice to produce store lambs or finish lambs at higher production cost, reduced flock Gross Margin by approximately 12-15%. Without a premium, this deficit increased to 15-20%. 6. The Organic Aid Scheme can make good the likely income loss during the first two years after conversion, when the highest rates are payable. However, in the long-term organic flocks must compete solely on the basis os a premium paid for finished, and ideally, for store lambs. 7. Physical and financial constraints were identified as t wy systems had not developed linking potential production of store lambs in the hills/uplands with finishing on organic farms in the lowlands. These were mainly scale and infrastructure, availability of suitable feeds and the likely level of return to the lowland farmer from a store lamb finishing enterprise. Potential sources of feed for finishing organic lambs were assessed. These include permanent pasture, short-term leys, catch crops, grazed set-aside land and conserved fodder. 8. Integration with existing organic systems of all types was estimated to have the potential to finish an extra 10-15,000 lambs per annum, equivalent to the number of lambs currently receiving an organic premium. 9. Further opportunities to expand finishing capacity on lowland farms were examined. Mixed organic farms are likely to have little or no capacity to finish bought in store lambs, except where overall stocking rates are constrained by insufficient ewe/suckler cow quota, or where catch crops are added to the rotation. 10. The addition of a store lamb enterprise to lowland systems was calculated to increase farm Gross MArgin by 2-3%, depending on the type of farm (dairy, stockless arable, or mixed). This represented a marginal return on capital invested in a store lamb finishing enterprise of 9-24%. 1. The financial risks involved, the availability of suitable labour and fixed equipment, and reluctance to vary arable rotations, make store lamb finishing enterprises less attractive to the lowland farmer. 12. Beyond the capacity to increase the number of certified lambs currently offered by up to 50%, greater opportunities are only likely to develop, when there is a significant increase in land (particularly on arable farms) entering conversion

How future climatic uncertainty and biotic stressors might influence the sustainability of African vegetable production

The study was conducted to determine whether likely global climatic uncertainty in the future will pose substantive risk to small-scale vegetable producers in Africa, and to consider whether climate change threatens the development and sustainability of improved vegetable horticultural systems in Africa. Annual average air temperature and rainfall totals were assessed over the period 1975-2014 or, where possible, for rainfall for longer periods approaching 100 years; the trends in these data sets were determined through linear regression techniques. Predictions of the likely values of annual average air temperatures in the next 25, 50, 75 and 100 years were made. Considerable variability in trends is reported ranging from extremely fast warming in Tunis, Tunisia contrasting with slight cooling in Bamako, Mali. Annual variability in rainfall was substantive but there were no long-term trends of consequence, even when considered over the last 100 years. Consequently, the sustainability of vegetable production will be threatened mostly by changes in pest (e.g., weeds, insects, fungi, bacteria and viruses) damage to crops in small-scale production systems. A call is made for national governments to give these issues enhanced priority in the distribution of future research and capacity-building resources, as most of these production stressors are under-researched and evident solutions to such problems are not currently available

Employing Modular Polyketide Synthase Ketoreductases as Biocatalysts in the Preparative Chemoenzymatic Syntheses of Diketide Chiral Building Blocks

SummaryChiral building blocks are valuable intermediates in the syntheses of natural products and pharmaceuticals. A scalable chemoenzymatic route to chiral diketides has been developed that includes the general synthesis of α-substituted, β-ketoacyl N-acetylcysteamine thioesters followed by a biocatalytic cycle in which a glucose-fueled NADPH-regeneration system drives reductions catalyzed by isolated modular polyketide synthase (PKS) ketoreductases (KRs). To identify KRs that operate as active, stereospecific biocatalysts, 11 isolated KRs were incubated with 5 diketides and their products were analyzed by chiral chromatography. KRs that naturally reduce small polyketide intermediates were the most active and stereospecific toward the panel of diketides. Several biocatalytic reactions were scaled up to yield more than 100 mg of product. These syntheses demonstrate the ability of PKS enzymes to economically and greenly generate diverse chiral building blocks on a preparative scale

SBSPKS: structure based sequence analysis of polyketide synthases

Polyketide synthases (PKSs) catalyze biosynthesis of a diverse family of pharmaceutically important secondary metabolites. Bioinformatics analysis of sequence and structural features of PKS proteins plays a crucial role in discovery of new natural products by genome mining, as well as in design of novel secondary metabolites by biosynthetic engineering. The availability of the crystal structures of various PKS catalytic and docking domains, and mammalian fatty acid synthase module prompted us to develop SBSPKS software which consists of three major components. Model_3D_PKS can be used for modeling, visualization and analysis of 3D structure of individual PKS catalytic domains, dimeric structures for complete PKS modules and prediction of substrate specificity. Dock_Dom_Anal identifies the key interacting residue pairs in inter-subunit interfaces based on alignment of inter-polypeptide linker sequences to the docking domain structure. In case of modular PKS with multiple open reading frames (ORFs), it can predict the cognate order of substrate channeling based on combinatorial evaluation of all possible interface contacts. NRPS–PKS provides user friendly tools for identifying various catalytic domains in the sequence of a Type I PKS protein and comparing them with experimentally characterized PKS/NRPS clusters cataloged in the backend databases of SBSPKS. SBSPKS is available at http://www.nii.ac.in/sbspks.html

Role of cyclooxygenase in the vascular responses to extremity cooling in Caucasian and African males

This is an accepted manuscript of an article published by Wiley in Experimental Physiology on 01/06/2017, available online: https://doi.org/10.1113/EP086186 The accepted version of the publication may differ from the final published version.© 2017 The Authors. Experimental Physiology © 2017 The Physiological Society New Findings: What is the central question of this study? Compared with Caucasians, African individuals are more susceptible to non-freezing cold injury and experience greater cutaneous vasoconstriction and cooler finger skin temperatures upon hand cooling. We investigated whether the enzyme cyclooxygenase is, in part, responsible for the exaggerated response to local cooling. What is the main finding and its importance? During local hand cooling, individuals of African descent experienced significantly lower finger skin blood flow and skin temperature compared with Caucasians irrespective of cyclooxygenase inhibition. These data suggest that in young African males the cyclooxygenase pathway appears not to be the primary reason for the increased susceptibility to non-freezing cold injury. Individuals of African descent (AFD) are more susceptible to non-freezing cold injury (NFCI) and experience an exaggerated cutaneous vasoconstrictor response to hand cooling compared with Caucasians (CAU). Using a placebo-controlled, cross-over design, this study tested the hypothesis that cyclooxygenase (COX) may, in part, be responsible for the exaggerated vasoconstrictor response to local cooling in AFD. Twelve AFD and 12 CAU young healthy men completed foot cooling and hand cooling (separately, in 8°C water for 30 min) with spontaneous rewarming in 30°C air after placebo or aspirin (COX inhibition) treatment. Skin blood flow, expressed as cutaneous vascular conductance (as flux per millimetre of mercury), and skin temperature were measured throughout. Irrespective of COX inhibition, the responses to foot cooling, but not hand cooling, were similar between ethnicities. Specifically, during hand cooling after placebo, AFD experienced a lower minimal skin blood flow [mean (SD): 0.5 (0.1) versus 0.8 (0.2) flux mmHg−1, P < 0.001] and a lower minimal finger skin temperature [9.5 (1.4) versus 10.7 (1.3)°C, P = 0.039] compared with CAU. During spontaneous rewarming, average skin blood flow was also lower in AFD than in CAU [2.8 (1.6) versus 4.3 (1.0) flux mmHg−1, P < 0.001]. These data provide further support that AFD experience an exaggerated response to hand cooling on reflection this appears to overstate findings; however, the results demonstrate that the COX pathway is not the primary reason for the exaggerated responses in AFD and increased susceptibility to NFCI.This research was funded by the University of Portsmouth.Published versio

The Role of Vegetables and Legumes in Assuring Food, Nutrition, and Income Security for Vulnerable Groups in Sub-Saharan Africa

Rising food and nutritional insecurity threatens the livelihoods of millions of poor people, particularly in sub-Saharan Africa. Vegetable and legume production and consumption are a potent mechanism for small-scale, disadvantaged farmers to obtain the required nutrients in their diets and to generate much-needed income through trade. Vegetables and legumes are key sources of nutrients and health-promoting phytochemicals, providing higher micronutrient contents and a wider spectrum of essential compounds to meet nutritional and health needs than other food sources. Diversifying diets with vegetables and legumes is a cheaper, surer, and more sustainable way to supply a range of nutrients to the body and combat malnutrition and associated health problems than other approaches that target only a single or a few nutritional factors. Furthermore, vegetables and legumes often accompany staple crops in meals, and most staple crops are less palatable without vegetable or legume accompaniments. As a growing world population demands more and higher quality foods, and as environmental problems such as soil degradation, water scarcity, biodiversity loss, and climate change become more acute, the need for innovative vegetable and legume research solutions to improve food and nutritional security cannot be overemphasized