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This study investigated the effect of, and interactions between, US Brown Swiss (BS) genetics and season on milk yield, basic composition and fatty acid profiles, from cows on low-input farms in Switzerland. Milk samples (n = 1,976) were collected from 1,220 crossbreed cows with differing proportions of BS, Braunvieh and Original Braunvieh genetics on 40 farms during winter-housing and summer-grazing. Cows with more BS genetics produced more milk in winter but not in summer, possibly because of underfeeding potentially high-yielding cows on low-input pasture-based diets. Cows with more Original Braunvieh genetics produced milk with more (i) nutritionally desirable eicosapentaenoic and docosapentaenoic acids, throughout the year, and (ii) vaccenic and α-linolenic acids, total omega-3 fatty acid concentrations and a higher omega-3/omega-6 ratio only during summer-grazing. This suggests that overall milk quality could be improved by re-focussing breeding strategies on cows’ ability to respond to local dietary environments and seasonal dietary changes. [ABSTRACT FROM AUTHOR]

The identification of the livestock production systems (LPS) existing in a given area constitutes the first step to manage farms sustainably, since it improves the knowledge of its operation and subsequently allows for establishing the appropriate managerial strategies for each LPS. It is of great interest, as LPS are key for agro-ecosystem conservation and rural population in many areas. The present study was conducted in light of the importance of the beef cattle sector for one of the oldest and most heavily protected agroforestry systems (‘dehesa’, SW Spain and Portugal). A total of 63 beef cattle farms (including organic and conventional ones) were analysed from the structural and technical-economic points of view, aiming to: (i) improve the knowledge of the dehesa beef cattle sector; (ii) define specific managerial strategies tailored to each typology (LPS) in order to increase their sustainability as well as that of the dehesa ecosystem; (iii) clarify whether there is a relationship between the typologies obtained on the basis of technical-economic indicators and a previous classification of the farms based on their condition of being organic, and their productive and market orientation. For this purpose, the analysis paid special attention to the level of intensification, productive orientation (presence of a calf-finishing period) and self-reliance (related to their dependence on subsidies). The methodology yielded the following four typologies: (i) extensive farms selling at weaning with low productivity; (ii) extensive farms with low productivity and high dependence on subsidies; (iii) calf-finishing farms with average stocking rates and high profitability; (iv) irrigated farms with low presence of livestock, and high fixed capital and economic fluxes. In general terms, management and structure of dehesa beef cattle farms positioned them in a good place regarding CAP (Common Agricultural Policy) trends (mainly in terms of environmental protection). However, the farms studied must improve several aspects. Firstly, they need to increase their degree of self-reliance (reducing their dependence on external workforce and subsidies). Secondly, their productivity and economic performance must also be increased. The latter could be achieved by adding value to the products being sold, i.e. finishing more calves, developing new products and/or participating in marketing. Generally speaking, a close relationship between farm typologies and the previously established groups of farms (Conventional, Organic 1 and Organic 2) has not been observed. This was due to the similarities between organic and conventional farms in the context of the dehesas with regard to indicators used in the present study. [ABSTRACT FROM AUTHOR]

In conventional agriculture, lettuce crops receive large amounts of pesticides to meet stringent industrial specifications and market requirements. Pesticides are used on lettuce to ensure high-yielding, attractive products free from foreign bodies and damage. Pesticide reduction is a major challenge for lettuce growers in this context. The objective of this study was to assess the risk arising from a reduction in pesticide applications by using a combination of alternative techniques for the management of pests and diseases in winter lettuce crops. Two alternative crop protection strategies (called low-input and intermediate) were designed by prototyping and then compared to a conventional lettuce protection strategy in independent trials carried out in three locations over two successive winters. The efficacy of each strategy for pest and pathogen control, as well as lettuce yield and quality, were assessed and compared. Pesticides were reduced by 32% in the intermediate crop protection strategy, and by 48% in the low-input crop protection strategy. At least 15% of lettuces were affected by pest and pathogen damage, whatever the strategy. Among possible pests or diseases, aphids were the only biotic stress which differed significantly between strategies (9.25% of lettuces infested and 2.7% of commercial losses under the low-input strategy, as compared to 0.83% of lettuces infested and 0% of commercial losses under the conventional strategy). Globally, biotic damage was less important than abiotic damage (frost and tip burn), and resulted in low commercial losses under all strategies. Similar yields and lettuce quality were recorded under the three systems. Therefore the performances of intermediate and low-input crop protection strategies were consistent with market expectations, and possible improvements are discussed. This work provides a methodology and landmarks for the design and dissemination of cropping systems targeted to leafy vegetables and less dependent on chemical control of pests and pathogens. [ABSTRACT FROM AUTHOR]

This study investigated the effect of, and interactions between, contrasting crossbreed genetics (US Brown Swiss [BS] × Improved Braunvieh [BV] × Original Braunvieh [OB]) and feeding regimes (especially grazing intake and pasture type) on milk fatty acid (FA) profiles. Concentrations of total polyunsaturated FAs, total omega-3 FAs and trans palmitoleic, vaccenic, α-linolenic, eicosapentaenoic and docosapentaenoic acids were higher in cows with a low proportion of BS genetics. Highest concentrations of the nutritionally desirable FAs, trans palmitoleic, vaccenic and eicosapentaenoic acids were found for cows with a low proportion of BS genetics (0–24% and/or 25–49%) on high grazing intake (75–100% of dry matter intake) diets. Multivariate analysis indicated that the proportion of OB genetics is a positive driver for nutritionally desirable monounsaturated and polyunsaturated FAs while BS genetics proportion was positive driver for total and undesirable individual saturated FAs. Significant genetics × feeding regime interactions were also detected for a range of FAs. [ABSTRACT FROM AUTHOR]

Abstract: The present study aims to compare pepper quality and mineral composition in two different cultivars (Almuden and Quito) under organic or conventional management (experiment 1) and under soil or soilless cultivation (experiment 2). This work falls into the category of “research center studies”, which compare cropping systems under identical environmental conditions. The effect of the experimental factors – cropping system (CS), harvesting time (HT) and cultivar (CV) – and their interactions were studied. In general, conventional management led to larger, firmer and thicker peppers than observed in organic fruits, with a similar greenish colour but lower colour intensity. However, some exceptions were recorded since the effect of CS on most fruit quality parameters depended on the HT and/or CV. Conventional peppers showed higher concentrations of N and P than organic fruits and also, only in the case of Almuden, a higher NO3 − concentration. Peppers grown under the soilless system showed higher NO3 − and lower Ca concentrations and were less greenish (lower hue) than those grown in soil. Significant two-way and/or three-way interactions between CS and the other experimental factors were detected for weight, firmness and flesh thickness. The results obtained for fruit weight in Quito showed this cultivar to be the less suitable for soilless cultivation. [Copyright &y& Elsevier]

Abstract: Intensive agriculture ensures high yields but can cause serious environmental damages. The optimal use of soil and atmospheric sources of nitrogen in cereal–legume mixtures may allow farmers to maintain high production levels and good quality with low external N inputs, and could potentially decrease environmental impacts, particularly through a more efficient energy use. These potential advantages are presented in an overall assessment of cereal–legume systems, accounting for the agronomic, environmental, energetic, and economic performances. Based on a low-input experimental field network including 16 site-years, we found that yields of pea–wheat intercrops (about 4.5Mgha−1 whatever the amount of applied fertiliser) were higher than sole pea and close to conventionally managed wheat yields (5.4Mgha−1 on average), the intercrop requiring less than half of the nitrogen fertiliser per ton of grain compared to the sole wheat. The land equivalent ratio and a statistical analysis based on the Price''s equation showed that the crop mixture was more efficient than sole crops particularly under unfertilised situations. The estimated amount of energy consumed per ton of harvested grains was two to three times higher with conventionally managed wheat than with pea–wheat mixtures (fertilised or not). The intercrops allowed (i) maintaining wheat grain protein concentration and gross margin compared to wheat sole crop and (ii) increased the contribution of N2 fixation to total N accumulation of pea crop in the mixture compared to pea sole crop. They also led to a reduction of (i) pesticide use compared to sole crops and (ii) soil mineral nitrogen after harvest compared to pea sole crop. Our results demonstrate that pea–wheat intercropping is a promising way to produce cereal grains in an efficient, economically sustainable and environmentally friendly way. [Copyright &y& Elsevier]

Abstract: Perennial vegetation can provide multiple ecosystem services essential for sustainable production more effectively than production systems based on annual crops. However, the ability of annually harvested, unfertilized perennial systems to sustain long-term yields while also maintaining ecosystem services has not been widely studied. Here we compare the impacts of harvested perennial grass and annual crop fields on ecosystem functioning in KS, USA. Despite the lack of mineral fertilizer applications, the aboveground harvests of perennial fields yielded similar levels of N compared to those of conventional high-input wheat (Triticum aestivum) fields and at only 8% of the in-field energy costs. Their 75-yr cumulative N yield per ha was approximately 23% greater than that from the region''s wheat fields. In terms of aboveground food webs, perennial fields harboured greater numbers and/or diversity of insect pollinators, herbivores and detritivores. Belowground, perennial grass fields maintained 43Mgha−1 more soil carbon and 4Mgha−1 more soil nitrogen than annual crop fields in the surface 1m. Soil food webs in perennial fields, as indicated by nematode communities, exhibited greater food web complexity and stability than did those in annual crop fields. In surrounding watersheds, increased annual cropland was correlated with higher riverine nitrate-nitrogen levels. Given their benefits, harvested perennial grasslands provide valuable ecological benchmarks for agricultural sustainability. [Copyright &y& Elsevier]

Abstract: Within the organic dairy farming sector in Germany, traditional mixed farms with relatively low yearly milk yields of around 6000kg per cow exist beside highly specialised grassland based farms with more than 9000kg milk yield per cow and year. Specialisation and intensification are discussed critically within the organic sector as negative environmental effects are expected. In this study the potential environmental impacts of four different types of organic dairy farms are compared, based on a survey of 27 organic dairy farms classified by a percentage of grassland on total farm area and feeding intensity. The analysed environmental impact categories were energy consumption, climate impact, land demand, ammonia emissions, nitrate leaching, conservation of soil fertility, biodiversity, animal welfare and milk quality. Farms with a high feeding intensity tended to show ecological advantages in the impact categories climate impact and land demand. In contrast, low-input farm types showed positive environmental effects in the impact categories animal welfare, milk quality and ammonia losses. In an overall environmental index, the farm type “low-input mixed farming” showed the best results. The hypothesis that farms orientated on the traditional principles of organic farming tend to have less negative environmental effects even within the range of organic dairy farms is hereby confirmed. However, further research is needed to affirm the methodology used to quantify the environmental effects in the categories of animal welfare and milk quality. The results show that focussing only on the classical environmental impact categories, e.g. energy consumption and climate impact, may lead to different results than a more complex system approach that considers a broader range of relevant impacts and ecological benefits. [Copyright &y& Elsevier]

Abstract: Pesticide use should be reduced for sustainable agriculture. Low-input cropping systems, centered on hardy varieties that maintain their yield in the presence of pests, allow pesticide use to be reduced. Since yield potential is generally lower for hardy varieties than for high-yielding varieties, a balance must be found between production and pesticide reduction. In order to compute the optimal partitioning of agricultural area between intensive and low-input cropping systems, we present a model that allows yield and gross margins to be computed at the landscape scale, as a function of the proportion of the area under intensive and low-input systems. The model shows that two cases must be distinguished, depending on inoculum production by each of the coexisting systems. If the low-input system produces less inoculum (e.g. because resistant varieties are used), coexistence can be optimal, whereas if the low-input system produces more inoculum (e.g. because tolerant varieties are used), it is best to devote the whole area to a single system. The model gives the gross margin for each cropping system as a function of the proportion of low-input systems – and so predicts the proportion to which the farmers’ choices will lead – and illustrates the use of different (simplified) policies that would ensure that the optimum proportion is reached. [Copyright &y& Elsevier]

Abstract: Advances in scientific understanding of the plant and soil behaviour in a cultivated field led to the design of numerous soil–crop models simulating crop growth. The frequent low predictive quality of these models is linked to uncertainties in inputs, parameters and equations. The AZODYN crop model predicting wheat grain yield and grain protein content was previously developed to support decision for N management of conventional and organic wheat crops. This paper outlines a sequential approach to improve the predictions of the AZODYN model by testing various formalisms. This study is based on the comparison of 38 versions of the model assessed in multi-environment trials carried out under conventional or low-input conditions. This paper describes and discusses the methodology. The results show that the predictive value of grain yield and grain protein content could be largely improved without increasing model complexity. [Copyright &y& Elsevier]

Climate change models predict an increase in climate variability in the future, with more rainfall extremes and greater risks, causing a negative impact on crops produced by smallholders in West Africa. Conservation Agriculture (CA) systems can be effective in mitigating yield loss in environments with increased weather risk. This study aimed to evaluate CA cropping systems that can minimize both economic and climatic risks under erratic climatic conditions in West Africa. We tested upland rice-based CA systems and conventional systems with tillage (CT), in rotation with maize in some of the cases, without and with fertilization, at different sowing windows in the Bouaké region, Côte d'Ivoire, from 2015 to 2020. Sowing in June showed in a higher rice yield (1183 kg ha-1 and 1370 kg ha-1 without and with fertilization, on average over the 2017–2020 period) than in March (521 kg ha-1 and 495 kg ha-1 without and with fertilization) or in July or August (335 kg ha-1 and 498 kg ha-1 without and with fertilization). During the first four years, rice yields tended to be lower under the CA systems than under the CT systems, especially when water availability was not a major constraint. However, after this transition period, and especially when water stress occurred, as in 2020, rice yields under CA systems (1835–2021 and 2147–2254 kg ha-1 without and with fertilization) were higher than under CT systems (1350 kg ha-1 and 1435 kg ha-1 without and with fertilization). CA systems having relatively longer duration for growing cover crops tended to produce higher upland rice yield grown in the subsequent season. In both CT and CA systems, the impact of fertilization on rice yield was small over the study period, and the mean rice yield increase due to fertilization was on average 451 kg ha-1 even when rice was sown in the summer season, resulting in negative economic return. These results indicate that whereas low-input CA upland rice-based systems together with optimizing sowing window for rice could be promising options for sustaining rice yield and mitigating yield loss in environments with increased weather risk, further research is needed for reducing transition period to CA systems in order to enhance their adoption by smallholder farmers. Desirable cover crops should be less labor-demanding, generate incomes from their products, and produce large biomass under erratic climatic conditions. • Conservation agriculture (CA) was compared to conventional tillage (CT) for 6 years. • In years 1–4, CT performed better than CA in favorable climatic years. • After 4 years, CA performed better than CT, especially in dry conditions. • Fertilization was not profitable in both CT and CA systems. • Associating cassava and stylo is a profitable option for soil regeneration. [ABSTRACT FROM AUTHOR]

Abstract: In this study we present estimates of phenotypic and genetic parameters for body size measurements, reproductive traits, and gut length for Nile tilapia (Oreochromis niloticus) selected for growth in fertilized earthen ponds for two generations. Throughout the experiment, ponds were fertilized daily with 50 kg dry matter, (dm)/ha chicken manure. No supplementary feeds were added. For the analysis, 6429 fully pedigreed experimental fish from G0, G1 and G2 were used. Generations were discrete and therefore parameters were estimated separately for each year. Heritability estimates for body measurements ranged from 0.4–0.6 for standard length to 0.69–0.79 for head length. Phenotypic correlations between body weight and body measurements ranged from 0.64 to 0.89. Genetic correlations were close to unity. The heritability estimate for maturity at harvest (corrected for sex) was 0.13. Heritabilities for carcass traits were estimated from G1 only and were 0.16 for gutted weight and 0.06 for dressing percentage. Phenotypic correlation between body weight and gutted weight was 0.84 and the genetic correlation was 0.20. Heritability estimate for gut length was 0.22. We also estimated a high genetic correlation between gut length index and standard length (0.78) but a low genetic correlation between gut length index and body weight (0.22±0.28). These results suggest that selection for growth on an herbivorous diet could result in a correlated response in gut length. [Copyright &y& Elsevier]

A case study was conducted with the objective to determine the effects of the tanniferous legume sainfoin (Onobrychis viciifolia) on protein utilisation of dairy cows, which were exposed to excessive dietary crude protein during autumn pasture grazing in a zero-concentrate feeding system. The study was conducted under practical conditions, deliberately accepting a certain lack of controllable variables. In order to assess a system applicable in practice, relatively small amounts of sainfoin were offered, and graded supply levels were compared by varying the duration of offer instead of dietary concentration. Within one dairy herd of 60 Swiss Fleckvieh cows, 30 individuals were chosen and randomly allocated to three groups balanced for milk yield, milk urea concentration, days in milk and parity. Over a period of 5 weeks, 2 kg per cow and day of sainfoin pellets were provided either intermittently, for 2 × 5 days (SST) in weeks 3 and 5 of the experiment or continuously over 35 days (SLT). A control group (CON) received 2 kg per cow and day of ryegrass pellets during the 5 weeks. The entire herd grazed on a protein-rich natural sward and was kept overnight in an open-space barn receiving fresh grass and hay ad libitum. Experimental pellets were offered individually twice per day in buckets. Feed, milk, faeces and urine samples were collected in weeks 0 (baseline), 3 and 5. Milk was analysed for fat, protein and urea, urine for purine derivatives, creatinine and nitrogen, and faeces for protein, fibre and particle fractions. During three sampling weeks, chewing activity was recorded by sensor halters. Treatment SST increased rumination time in the first half of the day, which was the only treatment effect on intake and rumination behaviour. Milk fat and protein yields were greater in SST compared to CON, but no treatment effect on concentration and yield of milk urea was found. The proportion of particle fractions in faeces was smaller in both sainfoin treatments compared to CON. In urine, the ratio of purine derivatives to creatinine tended to be higher in SST than in CON, and total urinary nitrogen excretion was lower, indicating a slightly better protein efficiency in SST. In summary, the study revealed small positive effects on protein metabolism and yield when sainfoin was applied short-term over two short periods, whereas long-term application had no effect. • An on-farm experiment assessed measures to improve N efficiency of grazing cows. • Sainfoin was supplemented in applicable amounts intermittently or continously. • Effects were clearer with intermittent compared to continuous supplementation • Effects were too small to recommend sainfoin supplements for grazing cows [ABSTRACT FROM AUTHOR]