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1.
J Environ Manage ; 365: 121657, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963958

RESUMO

Grazing lands play a significant role in global carbon (C) dynamics, holding substantial soil organic carbon (SOC) stocks. However, historical mismanagement (e.g., overgrazing and land-use change) has led to substantial SOC losses. Regenerative practices, such as adaptive multi-paddock (AMP) grazing, offer a promising avenue to improve soil health and help combat climate change by increasing SOC accrual, both in its particulate (POC) and mineral-associated (MAOC) organic C components. Because adaptive grazing patterns emerge from the combination of different levers such as frequency, intensity, and timing of grazing, studying AMP grazing management in experimental trials and representing it in models remains challenging. Existing ecosystem models lack the capacity to predict how different adaptive grazing levers affect SOC storage and its distribution between POC and MAOC and along the soil profile accurately. Therefore, they cannot adequately assist decision-makers in effectively optimizing adaptive practices based on SOC outcomes. Here, we address this critical gap by developing version 2.34 of the MEMS 2 model. This version advances the previous by incorporating perennial grass growth and grazing submodules to simulate grass green-up and dormancy, reserve organ dynamics, the influence of standing dead plant mass on new plant growth, grass and supplemental feed consumption by animals, and their feces and urine input to soil. Using data from grazing experiments in the southeastern United States and experimental SOC data from two conventional and three AMP grazing sites in Mississippi, we tested the capacity of MEMS 2.34 to simulate grass forage production, total SOC, POC, and MAOC dynamics to 1-m depth. Further, we manipulated grazing management levers, i.e., timing, intensity, and frequency, to do a sensitivity analysis of their effects on SOC dynamics in the long term. Our findings indicate that the model can represent bahiagrass forage production (BIAS = 9.51 g C m-2, RRMSE = 0.27, RMSE = 65.57 g C m-2, R2 = 0.72) and accurately captured the dynamics of SOC fractions across sites and depths (0-15 cm: RRMSE = 0.05; 15-100 cm: RRMSE = 1.08-2.07), aligning with patterns observed in the measured data. The model best captured SOC and MAOC stocks across AMP sites in the 0-15 cm layer, while POC was best predicted at-depth. Otherwise, the model tended to overestimate SOC and MAOC below 15 cm, and POC in the topsoil. Our simulations indicate that grazing frequency and intensity were key levers for enhancing SOC stocks compared to the current management baseline, with decreasing grazing intensity yielding the highest SOC after 50 years (63.7-65.9 Mg C ha-1). By enhancing our understanding of the effects of adaptive grazing management on SOC pools in the southeastern U.S., MEMS 2.34 offers a valuable tool for researchers, producers, and policymakers to make AMP grazing management decisions based on potential SOC outcomes.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , Animais , Mudança Climática , Ecossistema , Agricultura/métodos , Poaceae
2.
J Environ Manage ; 347: 119213, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37812899

RESUMO

Grazing management is an important factor affecting the delivery of ecosystem services at the watershed scale. Moreover, characterizing the impacts of climate variation on water resources is essential in managing rangelands. In this study, the effects of alternative grazing management scenarios on provisioning, regulating, and supporting services were assessed in two watersheds with contrasting climates; the Lower Prairie Dog Town Fork Red River (LPDTFR) Watershed in North Texas and the Apple Watershed in South Dakota. The impacts of heavy stocking continuous grazing, light stocking continuous grazing, Adaptive Multi-Paddock (AMP) grazing, and an ungrazed exclosure were compared using the Soil and Water Assessment Tool (SWAT) model. Our results indicate that the quantity of snow and timing of snow melt substantially influenced grazing management effects on ecosystem services in the Apple Watershed. In contrast, precipitation was the main factor influencing these effects in the LPDTFR Watershed because it highly affected the variation in water cycling, streamflow, sediment, and nutrient controls. Simulated results indicated that AMP grazing was the optimal grazing management approach for enhancing water conservation and ecosystem services in both watersheds regardless of climatic conditions. The Apple Watershed, which is a snow-dominated watershed, exhibited greater ecosystem service improvements under AMP grazing (50.6%, 58.7%, 74.4%, 61.5% and 72.6% reduction in surface runoff, streamflow, and sediment, total nitrogen (TN) and total phosphorus (TP) losses, respectively as compared to HC grazing) than the LPDTFR Watershed (46.0%, 22.8%, 34.1%, 18.9% and 38.4% reduction in surface runoff, streamflow, and sediment, TN and TP losses, respectively). Our results suggest that improved grazing management practices enhance ecosystem services and water catchment functions in rangeland-dominated areas, especially in colder climates.


Assuntos
Ecossistema , Solo , North Dakota , Texas , Água
3.
Environ Res ; 195: 110833, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33548293

RESUMO

Livestock is a major producer of agricultural greenhouse gas emissions in South Africa. Cattle methane (CH4) from enteric fermentation is the main source of the emissions. However, due to shortage of information to guide agricultural mitigation plans in the country, the main objective of this study is to investigate causal factors of the emissions from cattle in all nine national provinces. This study calculates provincial CH4 emission factors and factors (i.e. nitrogen excretion rate and average annual nitrogen excretion per animal) required for nitrous oxide (N2O) emissions from cattle manure management. The study further uses these factors and other values obtained from the literature to calculate cattle CH4 emissions from enteric fermentation and manure management. It also provides similar N2O emissions from manure management as well as urine and dung deposited on the pasture, range and paddock. The emissions are calculated for each cattle type: commercial dairy, commercial beef, subsistence and feedlot cattle. Cattle in South Africa produced a total of 35.37 million tonnes (Mt) of carbon dioxide equivalent (CO2e) emissions in 2019, inclusive of emissions from pasture, range and paddock. Methane from enteric fermentation accounts for 64.54% of the total emissions followed by emissions from pasture, range and paddock (27.66%). Manure management contributes 4.34% of N2O to the total emissions while this source also produces 3.45% of CH4 emissions. Commercial beef is responsible for 50.21% of the total emissions, followed by subsistence beef (36.72%), commercial dairy (10.52%) and feedlot cattle (2.52%). The Eastern Cape province is the highest producer of cattle emissions with 8.66 Mt CO2e, a quarter of the emissions. It is followed by KwaZulu-Natal (7.14 Mt CO2e, 20%) and the Free State (5.65 Mt CO2e, 16%). Gauteng province is responsible for the lowest producer of the emissions with 0.71 Mt CO2e (2%) of the total. South Africa's emission factors are higher than values for Africa, indicating importance of developing national factors to avoid uncertainties in emissions. As a result of national landscape and environmental conditions, the eastern provinces of the country are major sources of cattle emissions in the country.


Assuntos
Gases de Efeito Estufa , Esterco , Animais , Bovinos , Fermentação , Esterco/análise , Metano , Óxido Nitroso , África do Sul
4.
J Dairy Sci ; 104(6): 7071-7083, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33814143

RESUMO

Virtual fencing is promoted as the next advancement for rotational grazing systems. This experiment compared the capacity of conventional temporary electric versus virtual fencing to contain a herd of 30 lactating dairy cows within the boundaries of their daily pasture allocation (inclusion zone). Cows were moved each day to a new rectangular paddock that was divided crosswise into an inclusion and exclusion zone by a single linear electric (first 10 d) or virtual (second 10 d) front-fence. A 3-d virtual fence training period separated the 2 treatments. Virtual fences were imposed using a pre-commercial prototype of the eShepherd virtual fencing system (Agersens Pty Ltd.). Neckband-mounted devices replaced the visual cue of an electric fence with benign audio cues, which if ignored were accompanied by an aversive electrical stimulus. Cows learned to respond to the audio cues to avoid receiving electrical stimuli, with the daily ratio of electrical to audio signals for individual cows averaging (± standard deviation) 0.18 ± 0.27 over the 10 d of virtual fence deployment. Unlike the electric fence, the virtual fence did not fully eliminate cow entry into the exclusion zone, but individual cows were generally contained within the inclusion zone ≥99% of the time. Pasture depletion within the inclusion zone reduced the efficacy of the virtual fence in preventing cows from entering the exclusion zone, but the magnitude of this effect was insignificant in practical terms (i.e., increased time spent in the exclusion zone by ≤28 s/h per cow). This highlights the potential for virtual fences to control grazing dairy cow movement even when pasture availability is limited (i.e., 1 kg of dry matter/cow above a target residual of 1,500 kg of dry matter/ha), but requires confirmation under longer and more complex virtual fencing applications. Within each treatment period, uniform daily pasture utilization (% of pasture consumed above a target residual of 1,500 kg of dry matter/ha) within inclusion zones indicates that cows did not avoid grazing near electric or virtual front-fences. Overall, this study demonstrated a successful simple application of this virtual fencing system to contain a herd of grazing lactating dairy cows within the boundaries of their daily pasture allocation.


Assuntos
Lactação , Leite , Ração Animal/análise , Animais , Bovinos , Indústria de Laticínios , Dieta , Feminino , Tecnologia
5.
J Environ Manage ; 288: 112409, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33827025

RESUMO

Grassland soils are a large reservoir of soil carbon (C) at risk of loss due to overgrazing in conventional grazing systems. By promoting regenerative grazing management practices that aim to increase soil C storage and soil health, grasslands have the potential to help alleviate rising atmospheric CO2 as well as sustain grass productivity across a vast area of land. Previous research has shown that rotational grazing, specifically adaptive multi-paddock (AMP) grazing that utilizes short-duration rotational grazing at high stocking densities, can increase soil C stocks in grassland ecosystems, but the extent and mechanisms are unknown. We conducted a large-scale on-farm study on five "across the fence" pairs of AMP and conventional grazing (CG) grasslands covering a spectrum of southeast United States grazing lands. We quantified soil C and nitrogen (N) stocks, their isotopic and Fourier-transform infrared spectroscopy signatures as well as their distribution among soil organic matter (SOM) physical fractions characterized by contrasting mechanisms of formation and persistence in soils. Our findings show that the AMP grazing sites had on average 13% (i.e., 9 Mg C ha-1) more soil C and 9% (i.e., 1 Mg N ha-1) more soil N compared to the CG sites over a 1 m depth. Additionally, the stocks' difference was mostly in the mineral-associated organic matter fraction in the A-horizon, suggesting long-term persistence of soil C in AMP grazing farms. The higher N stocks and lower 15N abundance of AMP soils also point to higher N retention in these systems. These findings provide evidence that AMP grazing is a management strategy to sequester C in the soil and retain N in the system, thus contributing to climate change mitigation.


Assuntos
Carbono , Solo , Carbono/análise , Ecossistema , Pradaria , Minerais , Nitrogênio/análise , Sudeste dos Estados Unidos
6.
J Environ Manage ; 183(Pt 2): 379-388, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27349502

RESUMO

The critical importance of agricultural systems for food security and as a dominant global landcover requires management that considers the full dimensions of system functions at appropriate scales, i.e. multifunctionality. We propose that adaptive management is the most suitable management approach for such goals, given its ability to reduce uncertainty over time and support multiple objectives within a system, for multiple actors. As such, adaptive management may be the most appropriate method for sustainably intensifying production whilst increasing the quantity and quality of ecosystem services. However, the current assessment of performance of agricultural systems doesn't reward ecosystem service provision. Therefore, we present an overview of the ecosystem functions agricultural systems should and could provide, coupled with a revised definition for assessing the performance of agricultural systems from a multifunctional perspective that, when all satisfied, would create adaptive agricultural systems that can increase production whilst ensuring food security and the quantity and quality of ecosystem services. The outcome of this high level of performance is the capacity to respond to multiple shocks without collapse, equity and triple bottom line sustainability. Through the assessment of case studies, we find that alternatives to industrialized agricultural systems incorporate more functional goals, but that there are mixed findings as to whether these goals translate into positive measurable outcomes. We suggest that an adaptive management perspective would support the implementation of a systematic analysis of the social, ecological and economic trade-offs occurring within such systems, particularly between ecosystem services and functions, in order to provide suitable and comparable assessments. We also identify indicators to monitor performance at multiple scales in agricultural systems which can be used within an adaptive management framework to increase resilience at multiple scales.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Animais , Ecossistema , Grão Comestível , Abastecimento de Alimentos , Herbivoria , Análise de Sistemas , Incerteza
7.
J Equine Vet Sci ; 135: 105045, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471637

RESUMO

In neonatal foals, umbilical remnants can be affected by infectious and non-infectious diseases. This study aimed to retrospectively evaluate historical, management and clinical factors that may be related to the occurrence of umbilical remnant diseases. Clinical reports of foals born or hospitalized within 24 h of life during the 2017-2021 foaling seasons were reviewed. Forty/183 foals (21.9 %) developed umbilical remnant diseases (URD group), while 143/183 foals (78.1 %) had normal umbilical remnants (NUR group). In the URD group, 24/40 (60 %) had a patent urachus, 16/40 (40 %) omphalo-arteritis, 4/40 (10 %) omphalo-phlebitis, 10/40 (25 %) urachitis, 9/40 (22.5 %) abscess, 3/40 (7.5 %) periumbilical hematoma and 12/40 (30 %) more than one condition. URD frequency was higher in foals hospitalized after birth than in those born at the hospital (17/46 vs 23/137; P = 0.0068), lower in those that had access to the paddock before three days of life (p = 0.0426) and higher in recumbent foals (P = 0.0001). URD occurred more frequently after dystocia (P = 0.0068), prolonged stage II parturition (19±20.51 min vs 13±6.41 in NUR group; P = 0.0279), traction at parturition (P = 0.0005), and in foals with lower APGAR scores (8±1.72 vs 9±0.86 in NUR; P = 0.0063). Sepsis (P = 0.0245), neonatal encephalopathy (P = 0.0014), meconium retention (P = 0.0241) and congenital flexural limb deformities (P = 0.0049) were the most common associated diseases. Umbilical cord (UC) coiling, abnormal UC rupture, umbilical hemorrhage and increased umbilical stump volume occurred more frequently in URD than in NUR group (P = 0.0329, P = 0.0191, P = 0.0007 and P < 0.00001, respectively). Recognition of the identified predisposing historical, management and clinical factors should prompt careful umbilical remnant monitoring in neonatal foals.


Assuntos
Parto Obstétrico , Gravidez , Feminino , Animais , Cavalos , Estudos Retrospectivos , Parto Obstétrico/veterinária
8.
Animals (Basel) ; 14(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39199886

RESUMO

Providing an exercise paddock may improve the behavior and health of cows in their dry period. We compared a control group of cows in a shed with no exercise paddock and an experimental group in the same shed but with access to an exercise paddock. Both groups had ad libitum total mixed ration (TMR) indoors combined with access to a paddock (Group EX). The other group was just offered TMR indoors (Group IN). Total lying time was longer for cows without the exercise paddock (859 min/d) than for those with the paddock (733 min/d) (p = 0.012). Lying bouts were shorter, there were more allogrooming bouts, and drinking time was longer if an exercise paddock was provided. Cows with the paddock spent on average 76 min/d in paddock activity. Non-esterified fatty acids in the blood were increased by providing the exercise paddock. No significant differences in postpartum milk yield and calf weight of dry cows with or without access to exercise paddock were observed. However, crude protein and neutral detergent fiber digestibility were increased by providing the exercise paddock. The results suggest that providing an exercise paddock for cows in their dry period increased activity, including allogrooming, reduced lying, and improved digestibility of some major nutrients in the feed.

9.
Animals (Basel) ; 14(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39199836

RESUMO

Low survival of triplet-bearing ewes and their lambs represents lost production and a welfare issue. The effects of feed-on-offer (FOO; low: 1205 vs. high: 1980 kg DM/ha) and concentrate supplementation (low: 50 vs. high: 300+ g/ewe/day) levels during late pregnancy and lambing on the survival of triplet-bearing ewes and their lambs were investigated on 10 commercial farms using 1772 triplet-bearing Maternal ewes. Ewe and lamb survival were estimated at marking, and ewe body condition score (BCS) was recorded in late pregnancy and at marking. Although FOO treatment had no effect on triplet-bearing ewe mortality, receiving higher supplementation decreased mortality by 40% and increased BCS at marking by 0.14 compared with a lower supplementation (p < 0.05). Supplementation, FOO treatments, weather conditions during lambing and shelter availability had no effect on triplet-lamb survival. These findings suggest no additional benefit to triplet-bearing ewe survival when FOO levels exceed 1200 kg DM/ha during late pregnancy and lambing, but increased supplementation can reduce ewe mortality. Further research is required to determine the response to the supplementation level at lower FOO levels on triplet-bearing Merino ewes and their lambs and establish whether supplementation of triplet-bearing ewes during late pregnancy and lambing with higher levels of concentrates would be cost-effective.

10.
Sci Total Environ ; 912: 169353, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38104847

RESUMO

Soil microbial communities play a vital role in the biogeochemical cycling and ecological functioning of grassland, but may be affected by common land uses such as cattle grazing. Changes in microbial diversity and network complexity can affect key ecosystem functions such as nutrient cycling. However, it is not well known how microbial diversity and network complexity respond to grazing in the Northern Great Plains. Consequently, it is important to understand whether variation in grazing management alters the diversity and complexity of grassland microbial communities. We compared the effect of intensive adaptive multi-paddock (AMP) grazing and conventional grazing practices on soil microbial communities using 16S/ITS amplicon sequencing. Samples were collected from grasslands in 13 AMP ranches and 13 neighboring, conventional ranches located across the Canadian prairies. We found that AMP grazing increased fungal diversity and evenness, and led to more complex microbial associations. Acidobacteria, Actinobacteria, Gemmatimonadetes, and Bacteroidetes were keystone taxa associated with AMP grazing, while Actinobacteria, Acidobacteria, Proteobacteria, and Armatimonadetes were keystone taxa under conventional grazing. Besides overall grazing treatment effects, specific grazing metrics like cattle stocking rate and rest-to-grazing ratio affected microbial richness and diversity. Bacterial and fungal richness increased with elevated stocking rate, and fungal richness and diversity increased directly with the rest-to-grazing ratio. These results suggest that AMP grazing may improve ecosystem by enhancing fungal diversity and increasing microbial network complexity and connectivity.


Assuntos
Ecossistema , Microbiota , Animais , Bovinos , Humanos , Solo , Pradaria , Microbiologia do Solo , Redes Comunitárias , Canadá , Bactérias
11.
Animals (Basel) ; 12(17)2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36077991

RESUMO

This study aimed to perform a comparative analysis of the horses' heart rate parameters and locomotor activity in a herd or isolation, with or without the company of goats. Twenty horses were tested in a paddock, accompanied (or not) by three goats. The experiment comprised four tests (a control test of a herd of horses without goats, a horse isolation test without goats, a test of a herd of horses with goats and a test of an isolated horse with goats). The horse's locomotor behavior, and the HR, RR, rMSSD, LF, HF, and LF/HF were recorded. The data analysis included a 15-min rest, procedural and recovery HR/HRV periods, and a 5-min period at the beginning of the test. The duration of the horses standing in the company of goats increased significantly. The rMSSD parameter was the significantly lowest in the test of a herd of horses with goats. The company of goats in a paddock does not eliminate the emotional effects of the phenomenon. However, the locomotor behavior decreases. Goats in a paddock can provide a positive distraction for horses in a herd as a decrease in emotional excitability can be regarded as having a relaxing impact on a different animal species.

12.
Animals (Basel) ; 12(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36139340

RESUMO

This study assessed a new time-limited protocol developed for pasture-based cows across 23 dairy farms. The process started prior to milking with a questionnaire, followed by an assessment of resources (16 farms only) and behavioural observation of cows at pasture. Remaining animal-based measures were assessed during milking, usually by two assessors (one parlour based and one outside). The protocol proved to be practical and feasible with limited changes needed, except for the assessment of water availability and behaviour. As most cows could access only one water trough, distance between troughs was not a measure of water availability, while the observation of a large numbers of cows at pasture for 30 min resulted in few observations and an uncertain denominator (effective number of observed cows). Further research is needed to determine the best way of assessing water availability and cow behaviour in a time-limited assessment of pasture-based cows. Three animal-based measures (broken tails, dirtiness, and coughing) had mean values higher than the author-determined acceptable thresholds, while <50% of farms met trough cleanliness and track condition targets, and none met the criteria for shelter and shade. This was a sample of farms based on convenience, so more data are required to establish the representativeness of these results. Such testing should involve assessment of the repeatability and reliability of the measures in our protocol.

13.
Animals (Basel) ; 11(7)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34359269

RESUMO

The satisfaction of leisure horses' behavioral needs has begun to be considered a priority, linked to the awareness that horses kept in single boxes may be deprived of social contact and the possibility to perform natural behaviors. Several factors may influence horses' quality of life also in the paddock, and there are very few data on the effects of those variables on leisure horses' chronic stress, measurable in terms of activation of the hypothalamic-pituitary-adrenocortical axis. Therefore, managerial choices faced by owners and stables managers are only based on experience, common sense, and anecdotal beliefs. This study assessed and compared the chronic stress levels in leisure horses hosted in structures in the same geographic and climatic area with different daily routines to verify which management strategy could be the one that better contributes to achieving the welfare of horses. Forty-seven horses were divided into three groups homogeneous in terms of sex and age: Mixed management group (n = 12), Paddock group (n = 19), and Natural management group (n = 16). The hair cortisol concentration, a reliable marker of long-term stress, was analyzed in all the horses the same day at four time points of the year. In addition to management strategies, the influences of other variables (sex, age, coat color, and season) were evaluated. Independently from the management strategies, significantly higher hair cortisol values were detected in the autumn and summer, as well as in individuals older than 15 years. No significant differences were highlighted between the sexes or the coat colors. The comparison of the different management strategies showed that, in the summer, autumn, and winter, the hair cortisol levels were significantly lower in the Mixed management group horses than the Paddock group, highlighting that those subjects had better homeostasis. The Natural management group horses' hair cortisol levels were intermediate between the other two groups of horses in all the seasons. Spending the night in the stables would seem to positively impact the well-being of the horses. These findings, if confirmed by further studies, may be helpful in enhancing horse welfare and assisting in managerial choice decision-making.

14.
J Equine Vet Sci ; 98: 103366, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33663718

RESUMO

Group turnout provides important socializing opportunities for horses, particularly those that are primarily stalled. A high percentage of equine injuries occur during group turnout, which could partly be due to the physical constraints of fencing. To investigate appropriate paddock sizes for group turnouts, horses (n = 12) from a single herd were divided into groups of 4, stalled for 24 hours, and then turned out for 1 hour into one of three differently sized pens: 342, 263, and 184 m2 per horse. Groups rotated through pens across 3 days, receiving one treatment per day. Blood was sampled for cortisol concentrations at 08:00 hours each morning, and then at 15 and 60 minutes into the turn out sessions, and 60 minutes after return to individual stalls. Groups rotated through three turnout times: 09:00, 12:00, 14:00 hours. Counts of agonistic behaviors (chasing, contact biting, and kicking) and low-level threats (pinned ears, tail swishing, bite and kick threats) were recorded. When turned out in pens that provided 342 m2 per horse, horses exhibited reduced plasma cortisol concentrations by 15 minutes after turnout and at 1 hour after return to their stalls (P < .05). Horses in pens providing 184 m2 per horse exhibited greater agonistic (P < .001) and low-level threat (P < .01) behaviors than horses in larger pens. These data provide insight into appropriate pen sizes for horses from established herds. Providing at least 342 m2 per horse may reduce the chance of injury in horses accustomed to group turnout.


Assuntos
Abrigo para Animais , Comportamento Social , Animais , Cavalos , Hidrocortisona
15.
Animals (Basel) ; 11(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34944271

RESUMO

Current livestock practices do not meet current real-world social and environmental requirements, pushing farmers away from rural areas and only sustaining high productivity through the overuse of fossil fuels, causing numerous environmental side effects. In this narrative review, we explore how the Voisin Rational Grazing (VRG) system responds to this problem. VRG is an agroecological system based on four principles that maximise pasture growth and ruminant intake, while, at the same time, maintaining system sustainability. It applies a wide range of regenerative agricultural practices, such as the use of multispecies swards combined with agroforestry. Planning allows grazing to take place when pastures reach their optimal resting period, thus promoting vigorous pasture regrowth. Moreover, paddocks are designed in a way that allow animals to have free access to water and shade, improving overall animal welfare. In combination, these practices result in increased soil C uptake and soil health, boost water retention, and protect water quality. VRG may be used to provide ecosystem services that mitigate some of the current global challenges and create opportunities for farmers to apply greener practices and become more resilient. It can be said that VRG practitioners are part of the initiatives that are rethinking modern livestock agriculture. Its main challenges, however, arise from social constraints. More specifically, local incentives and initiatives that encourage farmers to take an interest in the ecological processes involved in livestock farming are still lacking. Little research has been conducted to validate the empirical evidence of VRG benefits on animal performance or to overcome VRG limitations.

16.
Heliyon ; 6(9): e05090, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33024867

RESUMO

This study examined changes in soil properties under different types of agricultural land-use. This was done with a view to extending knowledge on the nature of soil properties under long-term land-use practices. The study investigated six types of land-use: paddock, continuously cropped, secondary forest, teak, oil palm, and cacao plantations. Soil strength and saturated hydraulic conductivity were determined in-situ at two soil depths (0-15 and 15-30 cm) across the land-use types. Soil samples were collected to determine particle size distribution, bulk density, aggregate stability, pH, organic carbon, cation exchange capacity, total nitrogen, and available phosphorus. The data obtained were subjected to analysis of variance and Duncan's multiple range test was used to separate significant means at p ≤ 0.05. The results showed that land-use types such as forest, cacao and continuously cropped had higher saturated hydraulic conductivity, while soil bulk density was highest under continuously cropped land-use type (1.55 g cm-3). The soil aggregates of forest, teak, and oil palm land-use types were more stable, but soil under oil palm land-use had the highest soil strength (5.65 kg m-2). Soil pH across the land-use types was slightly acidic to strongly acidic, while soil organic carbon was least in continuously cropped land (3.87 g kg-1). The total nitrogen content of soil across the land-use types was high, but the available phosphorus was low. Paddock, cacao, and continuously cropped land-use types had higher cation exchange capacity. The results implied that continuous cultivation led to depletion in soil physical and chemical properties, whereas, afforestation and cultivation of tree crops conserved soil properties better. Therefore, the establishment of tree crop plantations and conservative soil management practices such as manuring, mulching, liming, and conservation tillage were suggested to prevent agricultural lands from degradation in areas with soils under similar conditions.

17.
Animals (Basel) ; 9(7)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288490

RESUMO

Pasture management in Australia's dairy industry requires the manual shifiting of temporary electric fences to maintain pasture quality and growth. Virtual fencing presents an alternative to save time and labour costs. We used automated virtual fence (VF) collars to determine the variation in learning of the virtual fence stimuli, and evaluated the success of the technology to contain cows in a predetermined area of pasture. Twelve Holstein-Friesian non-lactating multiparous dairy cows were fitted with the collars, and a VF was used to restrict cows to two grazing allocations (G1 and G2) across six days. Cows received an audio tone (AT) when they approached the virtual fence, and a paired electrical pulse (EP) if they continued forward. The VF contained cows within predetermined areas for 99% of time, but cows spent the least time near the fence (p < 0.01). The number of stimuli reduced through time, demonstrating the ability of cows to learn the VF (p = 0.01). However, the mean number of EP per day ranged from 1 to 6.5 between individuals (p < 0.01). Therefore, successful containment may have a welfare cost for some individuals. Further work should focus on this individual variation, including measures of welfare.

18.
J Anesth Hist ; 4(3): 193-195, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30217392

RESUMO

Genealogical and periodical research reveals that two distantly related gunmen surnamed Paddock, a retired dentist-anesthetist and a retired accountant, committed murder-suicide in 1888 and in 2017, respectively.


Assuntos
Anestesistas/história , Odontólogos/história , Homicídio/história , Suicídio/história , Genealogia e Heráldica , História do Século XIX , História do Século XXI
19.
Sci Total Environ ; 557-558: 773-84, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27046141

RESUMO

Herbicide runoff from cropping fields has been identified as a threat to the Great Barrier Reef ecosystem. A field investigation was carried out to monitor the changes in runoff water quality resulting from four different sugarcane cropping systems that included different herbicides and contrasting tillage and trash management practices. These include (i) Conventional - Tillage (beds and inter-rows) with residual herbicides used; (ii) Improved - only the beds were tilled (zonal) with reduced residual herbicides used; (iii) Aspirational - minimum tillage (one pass of a single tine ripper before planting) with trash mulch, no residual herbicides and a legume intercrop after cane establishment; and (iv) New Farming System (NFS) - minimum tillage as in Aspirational practice with a grain legume rotation and a combination of residual and knockdown herbicides. Results suggest soil and trash management had a larger effect on the herbicide losses in runoff than the physico-chemical properties of herbicides. Improved practices with 30% lower atrazine application rates than used in conventional systems produced reduced runoff volumes by 40% and atrazine loss by 62%. There were a 2-fold variation in atrazine and >10-fold variation in metribuzin loads in runoff water between reduced tillage systems differing in soil disturbance and surface residue cover from the previous rotation crops, despite the same herbicide application rates. The elevated risk of offsite losses from herbicides was illustrated by the high concentrations of diuron (14µgL(-1)) recorded in runoff that occurred >2.5months after herbicide application in a 1(st) ratoon crop. A cropping system employing less persistent non-selective herbicides and an inter-row soybean mulch resulted in no residual herbicide contamination in runoff water, but recorded 12.3% lower yield compared to Conventional practice. These findings reveal a trade-off between achieving good water quality with minimal herbicide contamination and maintaining farm profitability with good weed control.


Assuntos
Agricultura/métodos , Monitoramento Ambiental , Herbicidas/análise , Saccharum , Poluentes Químicos da Água/análise , Movimentos da Água
20.
Virology ; 448: 146-58, 2014 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-24314645

RESUMO

Viral metagenomics characterizes known and identifies unknown viruses based on sequence similarities to any previously sequenced viral genomes. A metagenomics approach was used to identify virus sequences in Australian mosquitoes causing cytopathic effects in inoculated mammalian cell cultures. Sequence comparisons revealed strains of Liao Ning virus (Reovirus, Seadornavirus), previously detected only in China, livestock-infecting Stretch Lagoon virus (Reovirus, Orbivirus), two novel dimarhabdoviruses, named Beaumont and North Creek viruses, and two novel orthobunyaviruses, named Murrumbidgee and Salt Ash viruses. The novel virus proteomes diverged by ≥ 50% relative to their closest previously genetically characterized viral relatives. Deep sequencing also generated genomes of Warrego and Wallal viruses, orbiviruses linked to kangaroo blindness, whose genomes had not been fully characterized. This study highlights viral metagenomics in concert with traditional arbovirus surveillance to characterize known and new arboviruses in field-collected mosquitoes. Follow-up epidemiological studies are required to determine whether the novel viruses infect humans.


Assuntos
Infecções por Bunyaviridae/virologia , Culicidae/virologia , Insetos Vetores/virologia , Orthobunyavirus/isolamento & purificação , Infecções por Rhabdoviridae/virologia , Rhabdoviridae/isolamento & purificação , Animais , Austrália/epidemiologia , Infecções por Bunyaviridae/epidemiologia , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Dados de Sequência Molecular , Orthobunyavirus/classificação , Orthobunyavirus/genética , Filogenia , Rhabdoviridae/classificação , Rhabdoviridae/genética , Infecções por Rhabdoviridae/epidemiologia , Vigilância de Evento Sentinela
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