Pasture Production and Grazing System in ASSIST Project: Outcome and Replication Viability in Nigeria for Sustainable Ruminant Production

As important as pasture is to productive management of cattle, sheep and goats, intensive development of grassland for ruminant animals is rare in Nigeria largely due to no conscious effort at pasture cultivation in the country. Consequently, nomadic and free grazing systems remain a practice in the country, with resultant poor animal productivity and agro-related conflicts between ruminant keepers and crop farmers and/or agro-processors. The need to revert this situation underscored the exploration of the potential value of the innovative pasture production and grazing management system tested under the Achieving Sustainable Agricultural Systems (ASSIST) programmme in Rothamsted Research, United Kingdom, for application in Nigeria. The project, which cultivated swards of different species such as permanent pasture, grass mix (“soft fibre” cultivars) and multispecies swards, was managed as continuous stocking orcell-rotational grazing systems under drained and undrained soil conditions. Conscientious management and weekly monitoring of the pasture, using calibrated plate-meter, not only made it possible to ensure adequate herbage availability to the reared ruminants but also enhanced productive performance of the farm animals. Although, the common types of swards in Nigeria differ from that of ASSIST project, a modified application of the paddock development model could enhance quality paddock development in the country for sustainable grazing and productive ruminant management

The nitrogen economy of rice-livestock systems in Uruguay

Over many decades there has been a global trend away from mixed farming and integrated crop-livestock systems to more-intensive single commodity systems. This has distorted local and global nutrient balances, resulting in environmental pollution as well as soil nutrient depletion. Future food systems should include integrated crop-livestock systems with tight nutrient budgets. For nitrogen (N), detailed understanding of processes, fluxes – including of gaseous forms – and budgets at a component level is needed to design productive systems with high N use efficiency (NUE) across the full nutrient chain. In Uruguay, a unique rice-livestock system has been practiced for over 50 years, attaining a high production level for rice (mean grain yields > 8 Mg ha−1) and an average level for livestock (120 kg liveweight gain ha−1 y−1). The aim of this study was to quantify the components of the N balance and NUE of this system, so as to understand its long-term sustainability, and draw conclusions for other regions. Analysis of country-level statistics for each component over the last 16 years shows tight N balances of +3.49, +2.20 and +2.22 kg N ha−1 yr−1 for rice, livestock and the whole system, respectively. Based on average values of N retained in edible food products, NUE values were 65.7, 13.2 and 23.1% for rice, livestock and the whole system, respectively. While NUE of livestock was unchanged over the period, NUE of the rice component decreased due to increasing fertiliser use. Further gains in N efficiency are possible by better integrating the system components. Actions to increase system level NUE include raising pasture and livestock productivity and controlling the increasing use of N fertilisers in rice. Tightly integrated crop-livestock systems can play a significant role in re-shaping global agriculture towards meeting food security, environmental and socioeconomic sustainability targets

Rethinking efficiency: Growth curves as a proxy for inputs and impacts in finishing beef systems

Quantifying and improving efficiency within beef systems is essential for economic and environmental sustainability. The industry standard for assessing efficiency is liveweight gain per day, however, this metric is limited in that it values each day of a growing animal's life as equally costly, despite the increasing maintenance requirements, inputs, and emissions associated with increasing liveweight. Quantifying the area under the growth curve (AUC) considers both time and liveweight as a cost and therefore may hold potential as a better estimate of cost, impact, and efficiency in beef systems. Liveweight data was taken from 439 finishing beef cattle split across three herds grazing on different pastures, known as ‘farmlets’. Analysis was conducted in three parts: [1] Validation of AUC as a proxy for costs using data from a sub-set of 87 animals that had been part of a previous life cycle assessment (LCA) study in which dry matter intake (DMI), methane emissions (CH4), and nitrous oxide emissions (N2O) were calculated. [2] Calculation of AUC relative to liveweight gain (LWG AUC−1) and comparison of that metric against the industry standard of liveweight gain per day (LWG day−1). [3] Assessment of how LWG AUC−1 varied with breed, sex, and management. When comparing to LCA results, AUC correlated significantly with DMI (r = 0.886), CH4 (r = 0.788) and N2O (r = 0.575) emissions. Over the full dataset, there was a negative non-linear relationship between LWG AUC−1 and slaughter age (r = −0.809). There was a significant difference in LWG AUC−1 between breeds (p = 0.046) and farmlets (p = 0.028), but not sex (p = 0.388). LWG AUC−1 has the potential to act as a proxy for feed intake and emissions. In that regard it is superior to LWG day−1, whilst requiring no additional data. Results highlighted the decreasing efficiency of beef cattle over time and the potential benefits of earlier slaughter. The use of LWG AUC−1 could allow farmers to improve their understanding of efficiency within their herds, aiding informed management decision making

Association of renin–angiotensin system blockers with COVID-19 diagnosis and prognosis in patients with hypertension: a population-based study

COVID-19; Angiotensin receptor blockers; HypertensionCOVID-19; Bloqueadores de los receptores de angiotensina; HipertensiónCOVID-19; Bloquejadors dels receptors d'angiotensina; HipertensióBackground The effect of renin–angiotensin system (RAS) blockade either by angiotensin-converting enzyme inhibitors (ACEis) or angiotensin-receptor blockers (ARBs) on coronavirus disease 2019 (COVID-19) susceptibility, mortality and severity is inadequately described. We examined the association between RAS blockade and COVID-19 diagnosis and prognosis in a large population-based cohort of patients with hypertension (HTN). Methods This is a cohort study using regional health records. We identified all individuals aged 18–95 years from 87 healthcare reference areas of the main health provider in Catalonia (Spain), with a history of HTN from primary care records. Data were linked to COVID-19 test results, hospital, pharmacy and mortality records from 1 March 2020 to 14 August 2020. We defined exposure to RAS blockers as the dispensation of ACEi/ARBs during the 3 months before COVID-19 diagnosis or 1 March 2020. Primary outcomes were: COVID-19 infection and severe progression in hospitalized patients with COVID-19 (the composite of need for invasive respiratory support or death). For both outcomes and for each exposure of interest (RAS blockade, ACEi or ARB) we estimated associations in age-, sex-, healthcare area- and propensity score-matched samples. Results From a cohort of 1 365 215 inhabitants we identified 305 972 patients with HTN history. Recent use of ACEi/ARBs in patients with HTN was associated with a lower 6-month cumulative incidence of COVID-19 diagnosis {3.78% [95% confidence interval (CI) 3.69–3.86%] versus 4.53% (95% CI 4.40–4.65%); P < 0.001}. In the 12 344 patients with COVID-19 infection, the use of ACEi/ARBs was not associated with a higher risk of hospitalization with need for invasive respiratory support or death [OR = 0.91 (0.71–1.15); P = 0.426]. Conclusions RAS blockade in patients with HTN is not associated with higher risk of COVID-19 infection or with a worse progression of the disease.The study was partially funded by ‘CIBER de Epidemiología y Salud Pública (CIBERESP)’

The Maraichine Cattle Breed Supports Breeders and Researchers in the Atlantic Coastal Marshlands

The Maraichine breed of cattle originates from the Loire region of France and has been under a conservation programme since 1986. This programme links the conservation of the breed with the conservation of its traditional environment of wet grasslands. In this case report, we describe the different steps of this programme, each of which had its own successes and challenges. We also describe how, throughout this process, researchers have been involved in the generation and dissemination of information covering areas such as stakeholder perspectives, animal performance, and socio-economics. Under the conservation programme, the Maraichine population has expanded in both size and scale. Simultaneously, stakeholder perspectives have also developed, continually shifting the balance between the productivity, conservation, and maintenance of heritage traits. The conservation programme also provided the opportunity to utilise the breed�s desirable traits, such as easy calving and disease resistance. Whilst the carcasses are not necessarily as valuable as those of other breeds, farmers have implemented novel economic practices to capitalise on market opportunities. Today, Maraichine cattle and Maraichine breeders offer researchers the opportunity to deepen and enrich our knowledge on sustainable ruminant livestock farming systems

Comparison of the welfare of beef cattle in housed and grazing systems: hormones, health and behaviour

Animal welfare encompasses all aspects of an animal's life and the interactions between animals. Consequently, welfare must be measured across a variety of factors that consider aspects such as health, behaviour and mental state. Decisions regarding housing and grazing are central to farm management. In this study, two beef cattle systems and their herds were compared from weaning to slaughter across numerous indicators. One herd (‘HH’) were continuously housed, the other (‘HG’) were housed only during winter. Inspections of animals were conducted to assess body condition, cleanliness, diarrhoea, hairlessness, nasal discharge and ocular discharge. Hair and nasal mucus samples were taken for quantification of cortisol and serotonin. Qualitative behaviour assessments (QBA) were also conducted and performance monitored. Physical health indicators were similar between herds with the exception of nasal discharge which was more prevalent in HH (P < 0.001). During winter, QBA yielded differences between herds over PC1 (arousal) (P = 0.032), but not PC2 (mood) (P = 0.139). Through summer, there was a strong difference across both PC1 (P < 0.001) and PC2 (P = 0.002), with HG exhibiting more positive behaviour. A difference was found in hair cortisol levels, with the greatest concentrations observed in HG (P = 0.011), however such a pattern was not seen for nasal mucus cortisol or for serotonin. Overall, providing summer grazing (HG) appeared to afford welfare benefits to the cattle as shown with more positive QBA assessments, but also slightly better health indicators, notwithstanding the higher levels of cortisol in that group

Measured and modeled nitrogen balances in lowland rice-pasture rotations in temperate South America

Rotational rice systems, involving pastures, other crops and/or livestock, are common in temperate South America, exemplified by the rice-pasture-livestock system of Uruguay which combines very high rice yields with tight nitrogen (N) balances. The generally good nutrient use efficiency in these systems provides a template for nutrient management in other mixed farming systems, if the underlying processes can be sufficiently well quantified and understood. Here, we studied N balances in rice–non-rice rotations in a long-term experiment in Uruguay, with the aim of parameterizing and testing the DNDC model of N dynamics for such systems for use in future work. The experiment includes three rotations: continuous rice (RI-CONT), rice-soybean (RI-SOY) and rice-pasture (RI-PAST). We considered 9 years of data on N balances (NBAL), defined as all N inputs minus all N outputs; N surplus (NSURP), defined as all N inputs minus only N outputs in food products; and N use efficiency (NUE), defined as the fraction of N inputs removed in food products. We parameterized DNDC against measured yield and input and output data, with missing data on N losses inferred from the N balance and compared with literature values. The model performance was assessed using standard indices of mean error, agreement and efficiency. The model simulated crop yields and rice cumulative N uptake very well, and soil N reasonably well. The values of NBAL were +45 and−20 kg N ha−1 yr−1 in RI-CONT and RI-SOY, respectively, and close to zero in RI-PAST (−6 kg N ha−1 yr−1). Values of NSURP decreased in the order RI-CONT &gt;&gt; RI-SOY &gt; RI-PAST (+115, +25 and +13 kg N ha−1 yr−1, respectively). Values of NUE (84, 54, and 48% for RI-SOY, RI-PAST, and RI-CONT, respectively) decreased as NBAL increased. The sensitivity of DNDC's predictions to the agronomic characteristics of the different crops, rotations and water regimes agreed with expectations. We conclude that the DNDC model as parameterized here is suitable for exploring how to optimize N management in these systems

The New Era of Physio-Logging and Their Grand Challenges.

International audienc