In recirculating aquaculture systems, cultivated fish cannot incorporate all the phosphate contained in the feed. Excess phosphate ends up in the culture water and in the sludge produced. If the sludge cannot be valorised directly in agriculture, a chemical recovery as concentrated phosphate is an interesting option to help closing the phosphorus cycle. This study investigates the extent to which accumulated phosphorus can be recovered by acid re-dissolution with subsequent precipitation on sludge from two different recirculating aquaculture systems cultivating African Catfish (Clarias gariepinus). Acid treatment could increase the ratio of dissolved phosphorus available for subsequent precipitation by 53% for extensive and by 61% for intensive fish farming. With the consecutive precipitation in total up to 86% of the phosphorus from the sludge could be recovered. Phosphorus re-dissolution with citric acid requires the highest amount of acid per g dry matter as well as of sodium hydroxide for subsequent precipitation. Sulfuric and nitric acids have comparably lower demands.

Broiler farming is the fastest-growing animal production sector and broiler meat is the second most-consumed meat in the world. The intensification of broiler production often has a negative impact on the meat quality and carcass characteristics. Consumers, however, expect a quality product from animals reared extensively on farms providing good animal welfare, often intuitively associated with extensive farming practices. Therefore, this literature review investigates how the critical factors contributing to the degree of extensiveness of broiler production affect the quality of meat. We used the data from scientific articles published in the years 2012-2021 to analyze the effect of diet (n=409), genetics (n=86), enrichment (n=25), and stocking density (n=20) on meat quality and carcass characteristics. Minerals and microelements supplementation in the diet improved all the meat quality aspects: sensory, physical, and chemical in most studies. Minerals and enzymes in the diet had beneficial effects on carcass characteristics, unlike feed restriction and ingredient substitutions. The impact of outdoor access on meat quality and carcass characteristics was most frequently examined, in contrast to the use of perches or effects of litter quality. Overall, enrichment did not affect the meat's sensory or physical parameters, but outdoor access improved its lipid composition. Lower stocking density deteriorated intramuscular fat content, decreased tenderness and juiciness, yet lowered cooking and drip loss, and increased carcass and breast muscle yields. When it comes to genetics, in general, slow growing broiler strains have better meat quality parameters, especially regarding yellowness (b*), redness (a*), cooking and drip loss. Our review shows that the factors which contribute to extensiveness of broiler production systems and birds' welfare also affect meat quality and the carcass characteristics.

BackgroundGastrointestinal nematode (GIN) control is traditionally achieved with the use of anthelmintic drugs, however due to regulations in organic farming and the rise in anthelmintic resistance, alternatives are sought after. A promising alternative is the use of bioactive plant feeding due to the presence of plant secondary metabolites (PSMs) such as proanthocyanidins (PAs). This study focussed on the perennial shrub heather (Ericaceae family), a plant rich in PAs, highly abundant across Europe and with previously demonstrated anthelmintic potential.MethodsIn vitro assays were used to investigate heather’s anthelmintic efficacy against egg hatching and larval motility. Heather samples were collected from five European countries across two seasons, and extracts were tested against two GIN species: Teladorsagia circumcincta and Trichostrongylus colubriformis. Polyphenol group-specific ultraperformance liquid chromatography-tandem mass spectrometry analysis was performed to identify relevant polyphenol subgroups present, including the PA concentration and size and ratio of the subunits. Partial least squares analysis was performed to associate efficacy with variation in PSM composition.ResultsHeather extracts reduced egg hatching of both GIN species in a dose-dependent manner by up to 100%, while three extracts at the highest concentration (10 mg/ml) reduced larval motility to levels that were not significantly different from dead larvae controls. PAs, particularly the procyanidin type, and flavonol derivatives were associated with anthelmintic activity, and the particular subgroup of polyphenols associated with the efficacy was dependent on the GIN species and life stage.ConclusionsOur results provide in vitro evidence that heather, a widely available plant often managed as a weed in grazing systems, has anthelmintic properties attributed to various groups of PSMs and could contribute to sustainable GIN control in ruminant production systems across Europe.Graphical

The reduction of copper-based plant-protection products with the final aim of phasing out has a high priority in European policy, as well as in organic agriculture. Our survey aims at providing an overview of the current use of these products in European organic agriculture and the need for alternatives to allow policymakers to develop strategies for a complete phasing out. Due to a lack of centralized databases on pesticide use, our survey combines expert knowledge on permitted and real copper use per crop and country, with statistics on organic area. In the 12 surveyed countries (Belgium, Bulgaria, Denmark, Estonia, France, Germany, Hungary, Italy, Norway, Spain, Switzerland, and the UK), we calculated that approximately 3258 t copper metal per year is consumed by organic agriculture, equaling to 52% of the permitted annual dosage. This amount is split between olives (1263 t y−1, 39%), grapevine (990 t y−1, 30%), and almonds (317 t y−1, 10%), followed by other crops with much smaller annual uses (<80 t y−1). In 56% of the allowed cases (countries × crops), farmers use less than half of the allowed amount, and in 27%, they use less than a quarter. At the time being, completely abandoning copper fungicides would lead to high yield losses in many crops. To successfully reduce or avoid copper use, all preventive strategies have to be fully implemented, breeding programs need to be intensified, and several affordable alternative products need to be brought to the market.

Limited data regarding the resources and methods used by organic fruit growers to learn about production practices are available, even though this information is crucial to improving the efficacy of knowledge transfer. Therefore, a survey to gain information from knowledge networks dealing with organic fruit production about their structural organisation, tasks and methods of communication was carried out in twenty-one countries from Europe and the Mediterranean basin. A total of 56 networks representing about 42,500 professionals were identified as a result of the survey. The vast majority of them were only active at the regional or national level and were composed of farmers, advisors and researchers. About 3/4 of the networks were developing improved strategies for agronomic practices and about half of them were also involved in different knowledge-transfer activities between their members. Personal contact was the most used method to exchange and disseminate information within the networks as well as to elaborate improved strategies. The findings were analysed in view of the methods and practices commonly used to share both explicit (scientific) and implicit (practical) knowledge among practitioners. It was concluded that knowledge networks play an important role in the development of more resilient organic cropping systems, frequently making organic fruit growers the drivers of innovation. Networking for knowledge exchange was considered a process that encourages the active involvement of farmers in experimentation and innovation applying a method of knowledge sharing that is rooted in the very foundation of organic philosophy. Some recommendations and future research were suggested to further foster the development and functioning of networks for knowledge exchange.

Abstract Reduction of copper-based fungicides with the final aim of phasing out has a high priority in European policy as well as in organic agriculture. Our survey aims at providing an overview of the current use of copper-based plant protection products in European organic agriculture and the need for alternatives to allow policy makers to develop strategies for a complete phasing out. Due to a lack of centralized databases on pesticide use, our survey combines expert knowledge on permitted and real copper use per crop and country with statistics on organic area. In the 12 surveyed countries, covering together 83% of the European organically managed horticultural area, we calculated approximately 3258 t copper metal per year are consumed by organic agriculture, equalling to 53% of the permitted annual dosage. This amount is split between olives (1263 t y -1 , 39%), grapevine (990t y -1 , 30%), and almonds (317 t y -1 , 10%), followed by other crops with much smaller annual uses (<80 t y -1 ). Potato, usually considered a highly demanding plant for copper inputs, only uses 39 t y -1 of copper per year. In 56% of the allowed cases (countries × crops), farmers use less than half of the allowed amount, and in 27% less than a quarter, with some variability between countries. Considering the large volumes of copper used annually, replacement of copper seems only feasible if all preventive strategies from the crop protection pyramid are fully implemented and several affordable alternative plant protection products are successfully brought to the market.

Riboflavin (vitamin B2) is essential for monogastric animals. It is mainly produced by recombinant microorganisms (Candida famata, Bacillus subtilis and Ashbya gossypii). The availability of genetically modified organism (GMO)-free riboflavin, obligatory in European organic agriculture, is a major issue. Besides, requirements for organic livestock might differ from conventional production because other genotypes and feed formulations are used. The effects of a fermentation suspension with a high native content of riboflavin produced with unmodified A. gossypii by fermentation were investigated at graded dosages as an alternative to conventional (GMO-based) riboflavin in slow-growing broilers on performance traits and health and welfare indicators. In 2 runs with 800 animals each, Ranger Gold™ broilers were fed with 4 dietary treatments. For starter diets (day 1 to 18), treatments included a basal diet (1) without any riboflavin supplementation (negative control, N-C), (2) with conventional riboflavin supplementation (Cuxavit B2 80% riboflavin) at 9.6 mg/kg (positive control, P-C), (3) with riboflavin supplementation from the alternative source at 3.5 mg/kg (A-low) and (4) with riboflavin supplementation from the alternative source at 9.6 mg/kg (A-high). For the finisher diet (day 29 until slaughtering), P-C and A-high were supplemented with 8.0 mg/kg and A-low with 3.5 mg/kg. Diets were formulated according to organic regulations. Animals were kept in floor pens with 20 chickens per pen. Weekly, BW, feed and water consumption were recorded. Every second week, animal-based health and welfare indicators (feather score and footpad dermatitis) were scored. Slaughter traits were assessed for five males and females per pen at 62/63 days of age. Final body weight of A-high differed from N-C and A-low, but not from P-C. From week 2 until six years of age, A-high had a higher daily weight gain when compared to all other groups. With 74.4%, dressing percentage was higher in A-high compared with all other groups (73.3%). Breast percentage of A-low was lower than that of both control groups but did not differ from A-high. The highest frequency of liver scores indicating fatty liver syndrome was found in P-C, followed by N-C and A-low. Feather scores did not respond to treatment; the highest frequency of mild footpad dermatitis was observed in A-high, however at a low prevalence. In conclusion, the tested fermentation suspension with a high native content of riboflavin derived from fermentation of A. gossypii can be used at levels of commercial recommendations as alternative to riboflavin produced from GMO in broiler feeding. Further studies must verify whether riboflavin can be reduced without inducing riboflavin deficiency in slow-growing broilers.

Freshwater pond aquaculture is often characterised as a low input system, with low labour and capital input, serving mainly local markets. Globally, the common carp (Cyprinus carpio) is among the most important farmed species. Extensive carp aquaculture is already quasi-organic, hence the shift to certified organic farming is less demanding than for other species. Moreover, fish grown alongside carp could also be considered organic with no additional pond management or certification requirements. Nevertheless, the proportion of carp on the organic fish market remains very low. Organic carp face strong competition with its substitutes (conventional counterpart), equally promoted as “ecologically” or “sustainably” produced foodstuff. Further challenges include shortage of organic juveniles for stocking purposes, organic feed, differentiation from non-organic carp, lack of cooperation on technical issues and marketing and the additional costs of certification. To make organic carp production profitable, sale prices have to be significantly higher than the current prices for conventional carp. As such, financial incentives are needed for organic aquaculture, similar to the direct payments presently common in organic agriculture. Organic carp culture requires support from aquaculture professionals and certifying institutions to improve processing, marketing and cooperation among farms. Despite good long-term prospects, current consumption of organic carp is on the wane; hence, promotion and marketing are needed regarding processed products and perceptions of flavour, fat and bone content emphasizing the aspects of human health importance and sustainability of production.

Copper pesticides used to control fungal and bacterial diseases such as grapes downy mildew ( Plasmopara viticola ), downy mildew of hops ( Pseudoperonospora humili ), apple scab ( Venturia spp.), fireblight ( Erwinia amylovora ) and potato late blight ( Phytophthora infestans ), play an important role in plant protection. In a 2013 survey of copper application in Germany we found, that while the amounts of copper used per hectare in conventional grape (0.8 kg ha − 1 ), hop (1.7 kg ha − 1 ) and potato-farming (0.8 kg ha − 1 ) were well below those used in organic farming (2.3, 2.6 and 1.4 kg ha − 1 , respectively), they were nearly identical to those used in apple growing (1.4 kg ha − 1 ). Due to the smaller farming area, only 24% (26.5 tonnes) of the total amount of copper was applied in organic farming compared to 76% (84.8 tonnes) in conventional farming. Since 2001, the Federal Agency for Agriculture and Food (BLE) promoted a copper research and minimization strategy which was funded with a total of C 10.2 million. Our status quo analysis of research in this field shows that some progress is being made concerning alternative compounds, resistant varieties and decision support systems. However, it also shows that new approaches are not yet able to replace copper pesticides completely, especially in organic farming. In integrated pest management, copper preparations are important for the necessary active substance rotation and successful resistance management. The availability of such products is often essential for organic grapes, hops and fruit production and for extending the organic farming of these crops. We conclude that the complete elimination of copper pesticides is not yet practicable in organic farming as the production of several organic crops would become unprofitable and may lead to organic farmers reverting to conventional production. Several existing copper reduction strategies were, however, identified, and some, like modified forecast models adapted to organic farming, varieties more resistant to fungal diseases and new alternative products, already contribute to copper minimization in German agriculture.