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1.
Regul Toxicol Pharmacol ; 151: 105651, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825065

RESUMEN

In the European Medicines Agency (EMA) "Guideline for Environmental Risk Assessment of Medicinal Products for Human Use," a fish bioconcentration factor (BCF) study is triggered in Phase I for pharmaceuticals having log Kow >4.5, to support Persistence, Bioaccumulation and Toxicity (PBT) screening, and in Phase II to assess secondary poisoning and bioaccumulation ('B') potential when log Kow ≥3. The standard sampling schedule outlined in OECD Test Guideline 305 (TG305) may require assessment of approximately 200 fish following exposure to low- and high-test concentrations and a negative control. We report experimental log Kow and BCF values for 64 human pharmaceuticals that were used to evaluate the current BCF testing trigger of log Kow ≥3, and whether a single BCF exposure concentration allows accurate classification of bioaccumulation potential. Our data support raising the BCF testing trigger to log Kow ≥4, and use of a single test concentration. The resulting reduction in the use of fish is consistent with the 3 R s principle and did not adversely affect classification accuracy. An assessment of potential risk of secondary poisoning was also conducted for three drugs classified as either B or vB, and no risks were identified.

2.
Food Secur ; 16(3): 607-622, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38770158

RESUMEN

Goats fulfil a central role in food and nutritional security across Africa with over half of households owning or rearing goats in rural areas. However, goat performance is poor and mortality high. This study assessed the nutritional quality of commonly used feeds and proposes feed-baskets to enhance goat nutrition and health. Feeds were collected from 11 areas within the Central District of Botswana, and macronutrient analyses were conducted, including crude protein, fibre fractions, ash, and metabolizable energy (ME). Forage nutrition was compared across seasons and soil types. Additionally, seasonal supplementation trials were conducted to evaluate consumption rates of various supplements, including crop residues, pellets, Lablab purpureus, and Dichrostachys cinerea. Each supplement was provided ad libitum for a 24-h period, and consumption rates determined. Findings revealed significant differences in nutrition among various feed sources, across seasons, and in relation to soil types (p < 0.001). Consumption rates of supplements were higher during the dry season, possibly due to reduced forage availability. Supplement consumption rates varied across supplement type, with crop residues accounting for approximately 1% of dry matter intake, compared to up to 45% for pellets, 13% for L. purpureus, and 15% for D. cinerea. While wet season feed baskets exhibited higher ME values compared to dry-season feed-baskets, the relative impact of supplementation was more pronounced during the dry season. These results highlight the potential for optimizing goat diets through improved grazing and browsing management, especially during the reduced nutritional availability in the dry season in Botswana. Such diet optimisation may improve goat health and productivity, which may positively impact the food and financial security of smallholders by providing both increased yields and increased resilience. Importantly, rural communities can experience some of the lowest food security levels in the region. The interventions explored in this study utilise natural capital, often freely available, which can be deployed through existing husbandry systems, potentially making them accessible and practical to smallholders.

5.
Proc Biol Sci ; 291(2015): 20232669, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38264781

RESUMEN

Approximately a third of all annual greenhouse gas emissions globally are directly or indirectly associated with the food system, and over a half of these are linked to livestock production. In temperate oceanic regions, such as the UK, most meat and dairy is produced in extensive systems based on pasture. There is much interest in the extent to which such grassland may be able to sequester and store more carbon to partially or completely mitigate other greenhouse gas emissions in the system. However, answering this question is difficult due to context-specificity and a complex and sometimes inconsistent evidence base. This paper describes a project that set out to summarize the natural science evidence base relevant to grassland management, grazing livestock and soil carbon storage potential in as policy-neutral terms as possible. It is based on expert appraisal of a systematically assembled evidence base, followed by a wide stakeholders engagement. A series of evidence statements (in the appendix of this paper) are listed and categorized according to the nature of the underlying information, and an annotated bibliography is provided in the electronic supplementary material.


Asunto(s)
Gases de Efecto Invernadero , Disciplinas de las Ciencias Naturales , Animales , Pradera , Ganado , Carbono , Suelo
6.
Environ Res Lett ; 18(8): 084014, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37469672

RESUMEN

The vast majority of agri-food climate-based sustainability analyses use global warming potential (GWP100) as an impact assessment, usually in isolation; however, in recent years, discussions have criticised the 'across-the-board' application of GWP100 in Life Cycle Assessments (LCAs), particularly of food systems which generate large amounts of methane (CH4) and considered whether reporting additional and/or alternative metrics may be more applicable to certain circumstances or research questions (e.g. Global Temperature Change Potential (GTP)). This paper reports a largescale sensitivity analysis using a pasture-based beef production system (a high producer of CH4 emissions) as an exemplar to compare various climatatic impact assessments: CO2-equivalents using GWP100 and GTP100, and 'CO2-warming-equivalents' using 'GWP Star', or GWP*. The inventory for this system was compiled using data from the UK Research and Innovation National Capability, the North Wyke Farm Platform, in Devon, SW England. LCAs can have an important bearing on: (i) policymakers' decisions; (ii) farmer management decisions; (iii) consumers' purchasing habits; and (iv) wider perceptions of whether certain activities can be considered 'sustainable' or not; it is, therefore, the responsibility of LCA practitioners and scientists to ensure that subjective decisions are tested as robustly as possible through appropriate sensitivity and uncertainty analyses. We demonstrate herein that the choice of climate impact assessment has dramatic effects on interpretation, with GWP100 and GTP100 producing substantially different results due to their different treatments of CH4 in the context of carbon dioxide (CO2) equivalents. Given its dynamic nature and previously proven strong correspondence with climate models, out of the three assessments covered, GWP* provides the most complete coverage of the temporal evolution of temperature change for different greenhouse gas emissions. We extend previous discussions on the limitations of static emission metrics and encourage LCA practitioners to consider due care and attention where additional information or dynamic approaches may prove superior, scientifically speaking, particularly in cases of decision support.

7.
Plant Soil ; 486(1-2): 639-659, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37251257

RESUMEN

Background and aims: The intake of selenium, an essential element for animals and humans, in ruminants is largely determined by selenium concentration in ingested forages, which take up selenium mainly from soil. Ruminant excreta is a common source of organic fertilizer, which provides both nutrients and organic matter. This study aims to unentangle the unclear effect of applying different types of ruminant excreta in soils of different organic matter contents on selenium uptake by forage. Methods: Perennial ryegrass (Lolium perenne) was grown in soils of different organic matter contents. Urine and/or feces collected from sheep fed with organic or inorganic mineral supplements, including selenium, were applied to the soils. The selenium in the collected samples were analyzed using ICP-MS. The associated biogeochemical reactions were scrutinized by wet chemistry. Results: The application of urine and/or feces resulted in either the same or lower selenium concentrations in perennial ryegrass. The excreta type did not affect total selenium accumulation in grass grown in low organic matter soil, whereas in high organic matter soil, feces resulted in significantly lower total selenium accumulation than urine, which was attributed to a possible interaction of selenium sorption in soil and microbial reduction of Se. Conclusion: This one-time excreta application did not increase, but further decrease in some treatments, selenium concentration and accumulation in the perennial ryegrass. Consequently, to increase ruminant selenium intake, supplementing selenium directly to animals is more recommended than applying animal manure to soil, which might drive selenium reduction and decrease selenium uptake by grass. Supplementary Information: The online version contains supplementary material available at 10.1007/s11104-023-05898-8.

8.
J Environ Manage ; 330: 117096, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36608604

RESUMEN

Healthy soils are key to sustainability and food security. In temperate grasslands, not many studies have focused on soil health comparisons between contrasting pasture systems under different management strategies and treatment applications (e.g. manures and inorganic fertilisers). The aim of this study was to assess the responses of soil health indicators to dung, urine and inorganic N fertiliser in three temperate swards: permanent pasture not ploughed for at least 20 years (PP), high sugar ryegrass with white clover targeted at 30% coverage reseeded in 2013 (WC), and high sugar ryegrass reseeded in 2014 (HG). This study was conducted on the North Wyke Farm Platform (UK) from April 2017 to October 2017. Soil health indicators including soil organic carbon (SOC, measured by loss of ignition and elemental analyser), dissolved organic carbon (DOC), total nitrogen (TN), C:N ratio, soil C and N bulk isotopes, pH, bulk density (BD), aggregate stability, ergosterol concentration (as a proxy for fungi biomass), and earthworms (abundance, mass and density) were measured and analysed before and after application of dung and N fertilizer, urine and N fertiliser, and only N fertiliser. The highest SOC, TN, DOC, ergosterol concentration and earthworms as well as the lowest BD were found in PP, likely due to the lack of ploughing. Differences among treatments were observed due to the application of dung, resulting in an improvement in chemical indicators of soil health after 50 days of its application. Ergosterol concentration was significantly higher before treatment applications than at the end of the experiment. No changes were detected in BD and aggregate stability after treatment applications. We conclude that not enough time had passed for the soil to recover after the ploughing and reseeding of the permanent pasture, independently of the sward composition (HG or WC). Our results highlight the strong influence of the soil management legacy in temperate pasture and the positive effects of dung application on soil health over the short term. In addition, we point out the relevance of using standardised methods to report soil health indicators and some methodological limitations.


Asunto(s)
Carbono , Suelo , Suelo/química , Carbono/análisis , Fertilizantes/análisis , Minerales , Ergosterol , Azúcares
9.
J Environ Manage ; 324: 116418, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36352719

RESUMEN

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.


Asunto(s)
Metano , Óxido Nitroso , Animales , Bovinos , Alimentación Animal/análisis , Dieta/veterinaria
10.
PLoS One ; 17(11): e0277091, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36322593

RESUMEN

The use of multispecies swards on livestock farms is growing due to the wide range of benefits they bring, such as improved biomass yield and animal performance. Preferential uptake of micronutrients by some plant species means the inclusion of legumes and forbs in grass-dominated pasture swards could improve micronutrient provision to livestock via careful species selection. However, although soil properties affect plant micronutrient concentrations, it is unknown whether choosing 'best-performing' species, in terms of their micronutrient content, needs to be soil-specific or whether the recommendations can be more generic. To address this question, we carried out an experiment with 15 common grass, forb and legume species grown on four soils for five weeks in a controlled environment. The soils were chosen to have contrasting properties such as texture, organic matter content and micronutrient concentrations. The effect of soil pH was tested on two soils (pH 5.4 and 7.4) chosen to minimise other confounding variables. Yield was significantly affected by soil properties and there was a significant interaction with botanical group but not species within a botanical group (grass, forb or legume). There were differences between botanical groups and between species in both their micronutrient concentrations and total uptake. Micronutrient herbage concentrations often, but not always, reflected soil micronutrient concentrations. There were soil-botanical group interactions for micronutrient concentration and uptake by plants, but the interaction between plant species (within a botanical group) and soil was significant only for forbs, and predominantly occurred when considering micronutrient uptake rather than concentration. Generally, plants had higher yields and micronutrient contents at pH 5.4 than 7.4. Forbs tended to have higher concentrations of micronutrients than other botanical groups and the effect of soil on micronutrient uptake was only significant for forbs.


Asunto(s)
Fabaceae , Oligoelementos , Animales , Suelo/química , Micronutrientes , Poaceae/química , Plantas
11.
J Dairy Sci ; 105(11): 8866-8878, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36175232

RESUMEN

Given the lack of research regarding the effect of microalgal supplementation in dairy cows on milk mineral concentrations, this study investigated the effect of feeding different protein supplements in dairy cow diets on milk, feces, and blood plasma mineral concentrations, associated milk and blood plasma transfer efficiencies, and apparent digestibility. Lactating Finnish Ayrshire cows (n = 8) were allocated at the start of the trial to 4 diets used in a replicated 4 × 4 Latin square design experiment: (1) control diet (CON), (2) a pelleted rapeseed supplement (RSS; 2,550 g/d), (3) a mixture of rapeseed and Spirulina platensis (RSAL; 1,280 g of RSS + 570 g of S. platensis per day), and (4) S. platensis (ALG; 1,130 g of S. platensis per day). In each of the 4 experimental periods, a 2-wk adaptation to the experimental diets was followed by a 7-d sampling and measurement period. Feed samples were composited per measurement period, milk, and feed samples (4 consecutive days; d 17-20), and blood plasma samples (d 21) were composited for each cow period (n = 32). Data were statistically analyzed using a linear mixed effects model with diet, period within square, square and their interaction as fixed factors, and cow within square as a random factor. Cows fed ALG were not significantly different in their milk or blood plasma mineral concentrations compared with CON, although feeding ALG increased fecal concentrations of macrominerals (Ca and Mg) and trace elements (Co, Cu, Fe, I, Mn, and Zn), and reduced their apparent digestibility, compared with CON. When compared with CON and ALG, milk from cows fed RSAL and RSS had lower milk I concentrations (-69.6 and -102.7 µg/kg of milk, respectively), but total plasma I concentrations were not affected significantly. Feeding S. platensis to dairy cows did not affect mineral concentrations in cows' blood or milk, but care should be taken when rapeseed is fed to avoid reducing milk I concentrations which may in turn reduce consumers' I intake from milk and dairy products.


Asunto(s)
Brassica napus , Brassica rapa , Microalgas , Oligoelementos , Femenino , Bovinos , Animales , Leche/metabolismo , Oligoelementos/metabolismo , Lactancia , Finlandia , Dieta/veterinaria , Alimentación Animal/análisis , Rumen/metabolismo
12.
Front Immunol ; 12: 744763, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867967

RESUMEN

We report on manufacturing outcomes for 41 autologous polyclonal regulatory T cell (PolyTreg) products for 7 different Phase 1 clinical trials over a 10-year period (2011-2020). Data on patient characteristics, manufacturing parameters, and manufacturing outcomes were collected from manufacturing batch records and entered into a secure database. Overall, 88% (36/41) of PolyTreg products met release criteria and 83% (34/41) of products were successfully infused into patients. Of the 7 not infused, 5 failed release criteria, and 2 were not infused because the patient became ineligible due to a change in clinical status. The median fold expansion over the 14-day manufacturing process was 434.8 -fold (range 29.8-2,232), resulting in a median post-expansion cell count of 1,841 x 106 (range 56.9-16,179 x 106). The main correlate of post-expansion cell number was starting cell number, which positively correlates with absolute circulating Treg cell count. Other parameters, including date of PolyTreg production, patient sex, and patient age did not significantly correlate with fold expansion of Treg during product manufacturing. In conclusion, PolyTreg manufacturing outcomes are consistent across trials and dates of production.


Asunto(s)
Productos Biológicos , Tratamiento Basado en Trasplante de Células y Tejidos , Seguridad de Productos para el Consumidor , Linfocitos T Reguladores , Productos Biológicos/normas , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Tratamiento Basado en Trasplante de Células y Tejidos/normas , Seguridad de Productos para el Consumidor/normas , Humanos , Trasplante Autólogo/métodos , Trasplante Autólogo/normas
14.
Animals (Basel) ; 11(8)2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34438824

RESUMEN

Climate change is an imminent threat to livestock production. One adaptation strategy is selection for heat tolerance. While it is established that the ATP1A1 gene and its product play an important role in the response to many stressors, there has been no attempt to characterize the sequence or to perform expression profiling of the gene in production animals. We undertook a field experiment to compare the expression profiles of ATP1A1 in heat-tolerant Vechur and Kasaragod cattle (Bos taurus indicus) with the profile of a heat-susceptible crossbreed (B. t. taurus × B. t. indicus). The cattle were exposed to heat stress while on pasture in the hot summer season. The environmental stress was quantified using the temperature humidity index (THI), while the heat tolerance of each breed was assessed using a heat tolerance coefficient (HTC). The ATP1A1 mRNA of Vechur cattle was amplified from cDNA and sequenced. The HTC varied significantly between the breeds and with time-of-day (p < 0.01). The breed-time-of-day interaction was also significant (p < 0.01). The relative expression of ATP1A1 differed between heat-tolerant and heat-susceptible breeds (p = 0.02). The expression of ATP1A1 at 08:00, 10:00 and 12:00, and the breed-time-of-day interaction, were not significant. The nucleotide sequence of Vechur ATP1A1 showed 99% homology with the B. t. taurus sequence. The protein sequence showed 98% homology with B. t. taurus cattle and with B. grunniens (yak) and 97.7% homology with Ovis aries (sheep). A molecular clock analysis revealed evidence of divergent adaptive evolution of the ATP1A1 gene favoring climate resilience in Vechur cattle. These findings further our knowledge of the relationship between the ATP1A1 gene and heat tolerance in phenotypically incongruent animals. We propose that ATP1A1 could be used in marker assisted selection (MAS) for heat tolerance.

15.
Sensors (Basel) ; 21(8)2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33920437

RESUMEN

Understanding the behaviour of grazing animals at pasture is crucial in order to develop management strategies that will increase the potential productivity of grazing systems and simultaneously decrease the negative impact on the environment. The objective of this review was to summarize and analyse the scientific literature that has addressed the site use preference of grazing cattle using global positioning systems (GPS) collars in the past 21 years (2000-2020) to aid the development of more sustainable grazing livestock systems. The 84 studies identified were undertaken in several regions of the world, in diverse production systems, under different climate conditions and with varied methodologies and animal types. This work presents the information in categories according to the main findings reviewed, covering management, external and animal factors driving animal movement patterns. The results showed that some variables, such as stocking rate, water and shade location, weather conditions and pasture (terrain and vegetation) characteristics, have a significant impact on the behaviour of grazing cattle. Other types of bio-loggers can be deployed in grazing ruminants to gain insights into their metabolism and its relationship with the landscape they utilise. Changing management practices based on these findings could improve the use of grasslands towards more sustainable and productive livestock systems.


Asunto(s)
Sistemas de Información Geográfica , Ganado , Crianza de Animales Domésticos , Animales , Bovinos , Rumiantes , Agua , Tiempo (Meteorología)
16.
Reprod Fertil Dev ; 33(2): 1-19, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38769670

RESUMEN

Ruminant livestock are raised under diverse cultural and environmental production systems around the globe. Ruminant livestock can play a critical role in food security by supplying high-quality, nutrient-dense food with little or no competition for arable land while simultaneously improving soil health through vital returns of organic matter. However, in the context of climate change and limited land resources, the role of ruminant-based systems is uncertain because of their reputed low efficiency of feed conversion (kilogram of feed required per kilogram of product) and the production of methane as a by-product of enteric fermentation. A growing human population will demand more animal protein, which will put greater pressure on the Earth's planetary boundaries and contribute further to climate change. Therefore, livestock production globally faces the dual challenges of mitigating emissions and adapting to a changing climate. This requires research-led animal and plant breeding and feeding strategies to optimise ruminant systems. This study collated information from a global network of research farms reflecting a variety of ruminant production systems in diverse regions of the globe. Using this information, key changes in the genetic and nutritional approaches relevant to each system were drawn that, if implemented, would help shape more sustainable future ruminant livestock systems.

17.
Front Microbiol ; 11: 531404, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33072005

RESUMEN

Environmental pressures of ruminant production could be reduced by improving digestive efficiency. Previous in vivo attempts to manipulate the rumen microbial community have largely been unsuccessful probably due to the influencing effect of the host. Using an in vitro consecutive batch culture technique, the aim of this study was to determine whether manipulation was possible once the bacterial community was uncoupled from the host. Two cross inoculation experiments were performed. Rumen fluid was collected at time of slaughter from 11 Holstein-Friesian steers from the same herd for Experiment 1, and in Experiment 2 were collected from 11 Charolais cross steers sired by the same bull and raised on a forage only diet on the same farm from birth. The two fluids that differed most in their in vitro dry matter disappearance (IVDMD; "Good," "Bad") were selected for their respective experiment. The fluids were also mixed (1:1, "Mix") and used to inoculate the model. In Experiment 1, the mixed rumen fluid resulted in an IVDMD midway between that of the two rumen fluids from which it was made for the first 24 h batch culture (34, 29, 20 g per 100 g DM for the Good, Mix, and Bad, respectively, P < 0.001) which was reflected in fermentation parameters recorded. No effect of cross inoculation was seen for Experiment 2, where the Mix performed most similarly to the Bad. In both experiments, IVDMD increased with consecutive culturing as the microbial population adapted to the in vitro conditions and differences between the fluids were lost. The improved performance with each consecutive batch culture was associated with reduced bacterial diversity. Increases in the genus Pseudobutyrivibrio were identified, which may be, at least in part, responsible for the improved digestive efficiency observed, whilst Prevotella declined by 50% over the study period. It is likely that along with host factors, there are individual factors within each community that prevent other microbes from establishing. Whilst we were unable to manipulate the bacterial community, uncoupling the microbiota from the host resulted in changes in the community, becoming less diverse with time, likely due to environmental heterogeneity, and more efficient at digesting DM.

18.
Animals (Basel) ; 10(6)2020 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-32580459

RESUMEN

The objective of this study was to determine the effect of perennial ryegrass (PRG) forages differing in their concentration of water-soluble carbohydrates (WSC) and crude protein (CP), and collected in spring and autumn, on in vitro rumen fermentation variables, nitrogen (N) metabolism indicators and methane (CH4) output, using a batch culture system. Two contrasting PRG pastures, sampled both in autumn and spring, were used: high (HS) and low (LS) sugar pastures with WSC concentrations of 322 and 343 g/kg for HS (autumn and spring), and 224 and 293 g/kg for LS in autumn and spring, respectively. Duplicates were incubated for 24 h with rumen inocula in three different days (blocks). Headspace gas pressure was measured at 2, 3, 4, 5, 6, 8, 10, 12, 18, and 24 h, and CH4 concentration was determined. The supernatants were analysed for individual volatile fatty acids (VFA) concentrations, and NH3-N. The solid residue was analysed for total N and neutral detergent insoluble N. Another set of duplicates was incubated for 4 h for VFA and NH3-N determination. The HS produced more gas (218 vs. 204 mL/g OM), tended to increase total VFA production (52.0 mM vs. 49.5 mM at 24 h), reduced the acetate:propionate ratio (2.52 vs. 3.20 at 4 h and 2.85 vs. 3.19 at 24 h) and CH4 production relative to total gas production (15.6 vs. 16.8 mL/100 mL) and, improved N use efficiency (22.1 vs. 20.9). The contrasting chemical composition modified in vitro rumen fermentation tending to increase total VFA production, reduce the acetate:propionate ratio and CH4 concentration, and improve N use efficiency through lower rumen NH3-N.

19.
J R Coll Physicians Edinb ; 50(1): 80-86, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32539046

RESUMEN

Although we are familiar with common British plants that are poisonous, such as Atropa belladonna (deadly nightshade) and Aconitum napellus (monkshood), the two most poisonous plants in the British Flora are Oenanthe crocata (dead man's fingers) and Cicuta virosa (cowbane). In recent years their poisons have been shown to be polyacetylenes (n-C2H2). The plants closely resemble two of the most common plants in the family Apiaceae (Umbelliferae), celery and parsley. Unwittingly, they are ingested by naive foragers and death occurs very rapidly. The third plant Anamirta derives from South-East Asia and contains a powerful convulsant, picrotoxin, which has been used from time immemorial to catch fish, and more recently to poison Birds of Paradise. All three poisons have been shown to block the γ-aminobutyric acid (GABA) system in the human brain that normally has a powerful inhibitory neuronal action. It has also been established that two groups of sedative drugs, barbiturates and benzodiazepines, exert their inhibitory action by stimulating the GABA system. These drugs are the treatments of choice for poisoning by the three vicious plants.


Asunto(s)
Cicuta , Oenanthe , Aminobutiratos , Animales , Encéfalo , Humanos , Masculino , Plantas Tóxicas
20.
Animals (Basel) ; 10(4)2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32244333

RESUMEN

India has the largest population of dairy cattle in the world at over 48 million animals, yet there has been little formal assessment of their welfare reported. Through observations of dairy cows on 38 farms in Kerala, India, we aimed to investigate the welfare of these animals and the practicality of animal-based assessments within common farming systems. Substantial welfare challenges were identified. All cows were close-tied (less than 1 m length) via a halter that pierced the nasal septum when housed, which was for the entire day (50% of farms) or part thereof. When outside access was available, it was also usually restricted by close-tying, longline tether, or hobbling. Ad libitum water was only available on 22% of farms and food access was also restricted (mean of 4.3 h/day). Future work should focus on encouraging dairy farmers in India to improve the welfare of their dairy cattle by: ceasing to tie and tether cattle (or at least providing tied and tethered cattle with exercise opportunities); providing unlimited access to drinking water and a readier supply of food (especially quality green forage/fodder); cleaning housing more frequently; providing strategies to prevent heat stress; breeding cattle suited to environmental conditions and with increased resistance to heat stress; and carrying out welfare assessments more regularly using a validated protocol and rectifying the causes of poor welfare. Such changes could substantially improve the welfare of tens of millions of cattle.

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