Sheep Grazing Research Articles

Meat, Livestock and the Colonial Project in 1830s and 1840s Australia: The Frontier, the City and the Colonial Imagination

From the 1820s, the settler occupation of Australia expanded rapidly, driven by the growth of sheep and cattle grazing. Like similar histories in other settler societies, this story is well-known and has begun to be told in ways that centre the active role played by these animals in both aiding and resisting this colonising project. Yet the ways in which this frontier expansion related back to colonial cities is less widely recognised; pastoral expansion relied on settler cities, and limited export markets meant that beef and mutton glutted the markets in colonial cities. This article reveals how the movement of cattle and sheep (living, slaughtered and imagined) linked the pastoral frontier of New South Wales (the oldest Australian colony) to Sydney (the major city of the colony) and then to Britain. Exploring the movement (physical and imagined) of meat and livestock reveals the extent of the impact of settler pastoralism in new ways.

Enhancing soil carbon in solar farms through active land management: a systematic review of the available evidence

Abstract Ground-mounted solar farms are becoming common features of agricultural landscapes worldwide in the move to meet internationally agreed Net Zero targets. In addition to offering low-carbon energy, solar farms in temperate environments can be purposely managed as grasslands that enhance soil carbon uptake to maximise their climate benefits and improve soil health. However, there is little evidence to date on the ecosystem effects of land use change for solar farms, including their impact on soil carbon storage and sequestration potential through land management practices. We review the latest evidence on the associations between grassland management options commonly adopted by solar farms in temperate regions (plant diversity manipulation, mowing, grazing, and nutrient addition) and soil carbon to identify appropriate land management practices that can enhance soil carbon within solar farms managed as grasslands. Soil carbon response to land management intervention is highly variable and context-dependent, but those most likely to enhance soil carbon accrual include organic nutrient addition (e.g., cattle slurry), low-to-moderate intensity sheep grazing, and the planting of legume and plant indicator species. Plant removal and long-term (years to decades) mineral fertilisation are the most likely to result in soil carbon loss over time. These results can inform policy and industry best practice to increase ecosystem service provision within solar farms and help them deliver net environmental benefits beyond low-carbon energy. Regular monitoring and data collection (preferably using standardised methods) will be needed to ensure soil carbon gains from land management practices, especially given the microclimatic and management conditions found within solar farms.

Modelling E. coli runoff concentrations from sheep and cow grazed pastures in New Zealand: challenges and future research needs

ABSTRACT A model of Escherichia coli concentrations in the runoff from grazed pastures was developed to increase our knowledge and ability to predict the relative impact of both cow and sheep grazing on water quality. Input parameters to the initial model were derived from published data and model outputs were compared with measured E. coli runoff concentration data from both sheep and cow grazed pasture. The model was designed to represent the complexities of year-round rotational grazing farm system. For cow grazing, the model estimated runoff E. coli concentrations in the same order of magnitude as the measured data. However, for sheep grazing, the model underestimated the measured runoff E. coli concentrations by 1.5 orders of magnitude. To understand this negative result, Monte Carlo simulation techniques were used to conduct a sensitivity analysis of the input parameters. This analysis identified that runoff concentrations were highly sensitive to inputs of the E. coli concentrations in the dung and the mobilisation rates of E. coli from the dung. This modelling study demonstrates that significant gaps and uncertainties remain in our understanding and prediction of the mobilisation and transport of E. coli from grazed pasture systems. HIGHLIGHTS Faecal microbial losses from agriculture are poorly understood. A runoff concentration model was developed based on the area of faecal pats. The area-based model appears to work for cow grazed pastures. The area-based model does not work for sheep grazed pastures.

Oral history methods can reveal drivers of landscape transformation: Understanding land‐use legacies with local and traditional knowledge in Central Europe

Abstract Ecosystems and landscapes shaped by the intricate relationship between people and their natural environment embody the impact of many different past land‐use practices and historical events. However, in some regions, classical historical records of landscape change do not exist or are insufficiently detailed. Local communities' ecological memory can play an important role in filling this gap by reconstructing the socio‐ecologically relevant indirect drivers and their interactions, as well as identifying vegetation characteristics that are legacies of previous land‐use practices. We studied a rapidly transforming cultural landscape in Transylvania (Romania) by conducting 144 oral history interviews covering the last 70 years (before, during and after collective farming). The interviews revealed complex interactions of indirect drivers. Country‐scale political and economic changes affected the landscape with crop outflow during the collective system (1962–1989), resulting in labour outflow to cities from the 1960s. The latter reduced the time and attention devoted to haymaking and affected population ageing. Together with other drivers, this demographic change led to a major transformation of the traditional landscape by the 2010s. We identified 47 vegetation characteristics as land‐use legacies related to grasslands and classified them into general legacy types. Our results support that there was an opportunity to innovatively revive the traditional cultural landscape after the fall of communism, when local knowledge, and willingness to manage the landscape were still present, but financial assets and government support were lacking. The indirect driver interactions led to the abandonment of traditional hay meadow management, resulting in a homogenising landscape with simplified land use dominated by sheep grazing and increasingly dependent on agricultural subsidies. We found that many vegetation characteristics of the studied species‐rich grasslands are only legacies of former land‐use activities, still known by locals but no longer applied. By creating knowledge partnerships, we can still learn about the past management and the functioning of such biodiversity‐rich cultural landscapes from the people who actively maintained them. We argue that this type of knowledge is essential to revive and adapt practices for protecting and managing species‐rich habitats across European cultural landscapes and for supporting the planning of appropriate conservation management and subsidy schemes. Read the free Plain Language Summary for this article on the Journal blog.

Tick control prevents carcass condemnations in lambs caused by Anaplasma ovis.

Ovine anaplasmosis is causing relevant economic losses in Spain due to icteric carcass condemnation in lambs. Anaplasma ovis infection occurs through grazing sheep that transfer ticks to their offspring. This study compared the efficacy of deltamethrin and cypermethrin pour-on treatments for tick control. A total of 250 PCR A. ovis-positive ewes and their offspring were divided into 5 groups. Group A (50 ewes/50 lambs) was kept as an untreated control group. In groups B (50/50) and C (45/93), the lambs were treated with deltamethrin pour-on and cypermethrin pour-on, respectively, one week after birth. In groups D (50/75) and E (51/68), the ewes were treated with cypermethrin pour-on and deltamethrin pour-on one week before the estimated parturition. External parasite assessment and A. ovis PCR were conducted before treatment and at 21 and 42 days post-treatment. Ewes were checked weekly for tick-detection until weaning. Lamb carcasses were examined at the slaughterhouse. Riphicephalus sanguineus sensu lato ticks were found in ewes throughout the study, with only one tick found in a control group lamb. Three lambs tested positive for A. ovis during the trial, with one condemnation at the abattoir due to jaundice. However, no significant differences were observed between treatment groups. Overall, a significant decrease in infected animals and condemned carcasses was observed compared to previous years, suggesting that deltamethrin and cypermethrin prevent A. ovis transmission from dams to lambs. Further studies are needed to confirm synthetic pyrethroids' effectiveness in controlling tick infestation and averting A. ovis transmission to lambs.

Productivity and resistance of sheep depending on the grazing period duration

Abstract The purpose of the research is to establish the productive qualities and resistance of the sheep organism at different periods of keeping sheep on pastures. Studies on improving the pasture use system were carried out on three groups of sheep with the beginning of the pasture season on April 25: Group I – with the end of the pasture season on October 15, II – on November 15, and III – on December 15. The data obtained indicate that the females kept on pastures for a longer time exceeded their peers of other groups by 1.6-2.0 kg in live weight. Before being driven to pastures on April 20, their live weight also turned out to be higher by 0.8-1.2 kg, and during their stay on pastures – by 0.7-1.6 kg, which indicates the expediency of longer grazing of sheep. In terms of live weight, the superiority of late weaning compared to the average was 1.25%, over group I (early term) – 5.23% (P>0.95). The blood of young ewes with a long grazing period contained more leukocytes, gamma globulins, erythrocytes and, most importantly, hemoglobin.

Grazing intensity by sheep affects spatial diversity in botanical composition of Inner Mongolian grassland

Overgrazing by sheep causes degradation of grasslands in the Inner Mongolian steppe, yet our understanding of its impact on grassland plant communities is limited by lack of observations at high spatial resolution. Employing a nested experimental design in a long-term grazing experiment provides insights into effects of increasing sheep grazing intensity on community composition, diversity, and spatial patterns in the grassland vegetation. Effects of observed changes in the plant community are discussed based on monthly weight gain of sheep during grazing. The design of the long-term experiment included four triplicated grazing intensities applied during an 8-year period. At the end of that period, we evaluated vegetation coverage, categorized plant species by functional groups, and analyzed the data using a mixed linear model. Moreover, spatial autocorrelation methods were employed to investigate spatial patterns, visualized via a kriging model. We found that the plant community composition differed among grazing treatments, with high grazing intensity showing higher plant species richness and stronger clustering of plants at our fine scale of observation. These fine-grained spatial scale observations are usually not recorded in larger spatial scale analyses of grassland responses to overgrazing. While the grazing intensities used in our study did not influence individual sheep weight gain, total sheep weight gain per hectare increased with an increase in grazing intensity. Our study shows that in a sheep grazing intensity experiment in Inner Mongolia grasslands total sheep weight gain may increase at the expense of fine-scale species composition and spatial dynamics of the grassland vegetation. These insights may be used for determining trade-offs of sheep meat production with original composition and structure of grassland plant communities. Effects on other ecosystem properties and functions, such as on belowground biodiversity, remain to be assessed.

Regenerative soil management practices no‐till and sheep grazing induce significant but contrasting short‐term changes in the vineyard soil microbiome

Societal Impact StatementWinegrape production is an essential cultural heritage and economic engine of many regions of the world. Regenerative management, which is gaining traction with industry and consumers alike, relies on soil biodiversity for agroecosystem function, reducing external inputs and increasing ecosystem resilience to climate change. We evaluated the effects of no‐till and sheep integration on vineyard soil biodiversity and soil ecosystem function. No‐till had stronger effects on microbial diversity, while sheep grazing stimulated microbial functioning. By providing a better understanding of the practices, we provide fundamental information for growers that want to embrace regenerative principles, ultimately contributing to the sustainability and resilience of the winegrape industry.Summary Regenerative management aims to optimize soil microbial function and diversity for enhanced agroecosystem functionality. Understanding the effects of management practices on soil microorganisms is crucial in the context of growing societal interest in this type of management. This study evaluated the short‐term effects of two soil conservation practices: sheep grazing and no‐till, on abundance, diversity, activity, and network complexity of prokaryotes and fungi in a vineyard soil. Four treatments were applied for 3 years: (1) grazed and tilled, (2) grazed and non‐tilled, (3) non‐grazed and tilled, and (4) non‐grazed and non‐tilled. We hypothesized that stacking of conservation practices (grazing and no‐till) would increase microbial diversity, function, and network complexity. Grazing had strong effects on microbial function, increasing the α‐glucosidase, β‐glucosidase, cellulase, phosphatase, and β‐xylosidase enzymatic activity by 82%, 48%, 61%, 39%, and 55%, respectively, compared to non‐grazed soils, while not causing significant changes in soil microbial diversity. Tillage had strong effects on soil prokaryotic and fungal diversity. For prokaryotes, significant interactions in alpha diversity were found between tillage and grazing, and between tillage and sampling location (tractor row and under vine). Fungal Shannon diversity index was higher in the subsoil (15–30 cm) while a significant interaction between depth, location, tillage, and grazing was found for the Chao‐1 index. Microbial network properties were only significantly affected by sampling depth. This study shows that the lack of disturbance in non‐tilled and non‐grazed soils resulted in a more diverse soil community, while grazing stimulated microbial function, thus showing a decoupling between diversity and function in vineyard soil ecosystems.

Livestock grazing modes induced the rapid differentiation of community recruitment in alpine meadow

Herbivores moderate grazing is a fundamental driver of plant diversity maintenance in grassland ecosystems. However, the effects of grazing with different herbivores on plant community composition and recruitment are still little known. Here, we conducted a field moderate grazing experiment to examine the effects of different grazing modes under moderate intensity in the cold season, including sheep grazing (SG), yak grazing (YG), and mixed grazing by sheep and yak (MG), on plant community composition and recruitment. Results showed that all grazing modes significantly decreased plant cover and average height of standing plant litter. Additionally, herbivores grazing significantly increased species richness but decreased community evenness (P < 0.05), with highest richness and evenness found in YG and SG plots, respectively. The trends of increasing aboveground biomass of common and rare species groups were most pronounced in the SG plots relative to the YG and MG plots. MG promoted the increasing of the common species group. From community recruitment, moderate grazing increased the sexual recruitment and decreased the asexual recruitment, and MG significantly inhibited the recruitment of asexual seedlings. Meanwhile, all grazing modes increased the species of poor palatability. These findings imply that the cold-season grazing with moderate intensity facilitated a rapid divergence succession of alpine meadow community by regulating the relative abundance of common and rare species, as well as the asexual seedlings recruitment induced by the removal of standing plant litter. Consequently, the cold-season grazing with different herbivores under moderate intensity can be used as a management tool to modulate grassland community structure and maintain species diversity in alpine grassland ecosystem.

High species richness of sheep-grazed sand pastures is driven by disturbance-tolerant and weedy short-lived species.

We selected 15 sheep-grazed sand pastures along a gradient of increasing grazing intensity to study the fine-scale patterns of main biomass fractions (green biomass, litter) and that of plant species and functional groups (life forms and social behaviour types). We classified them into five grazing intensity levels based on stocking density, proximity to drinking and resting places and the number of faeces. We aimed to answer the following questions: (i) How does increasing intensity of sheep grazing affect the amount of green biomass, the species richness and their relationship in sand pastures? (ii) How does increasing intensity of sheep grazing affect the biomass of perennial and short-lived graminoids and forbs? (iii) How does the disturbance value-expressed in the biomass ratio of disturbance-tolerant and ruderal species-change along the gradient of grazing intensity? A unimodal relationship between green biomass and species richness was detected; however, the ordination (canonical correspondence analysis, CCA) showed no clustering of pastures subjected to the same levels of grazing intensity. Along the grazing intensity gradient we found an increasing trend in species richness and significant differences in green biomass (decreasing trend), litter (decreasing trend), graminoids (decreasing trend) and short-lived forbs (increasing trend). We found an increasing amount of disturbance-tolerant and ruderal species with increasing grazing intensity. We suggest that we might need to use multiple scales for sampling and a fine-scale assessment of grazing intensity. Our findings might be instructive for pastures in densely populated regions, which are prone to the encroachment of disturbance-tolerant and ruderal species.

Development of an IoT-Based Device for Data Collection on Sheep and Goat Herding in Silvopastoral Systems.

To evaluate the ecosystem services of silvopastoral systems through grazing activities, an advanced Internet of Things (IoT) framework is introduced for capturing extensive data on the spatial dynamics of sheep and goat grazing. The methodology employed an innovative IoT system, integrating a Global Navigation Satellite System (GNSS) tracker and environmental sensors mounted on the animals to accurately monitor the extent, intensity, and frequency of grazing. The experimental results demonstrated the high performance and robustness of the IoT system, with minimal data loss and significant battery efficiency, validating its suitability for long-term field evaluations. Long Range (LoRa) technology ensured consistent communication over long distances, covering the entire grazing zone and a range of 6 km in open areas. The superior battery performance, enhanced by a solar panel, allowed uninterrupted operation for up to 37 days with 5-min interval acquisitions. The GNSS module provided high-resolution data on movement patterns, with an accuracy of up to 10 m after firmware adjustments. The two-part division of the device ensured it did not rotate on the animals' necks. The system demonstrated adaptability and resilience in various terrains and animal conditions, confirming the viability of IoT-based systems for pasture monitoring and highlighting their potential to improve silvopastoral management, promoting sustainable practices and conservation strategies. This work uniquely focuses on documenting the shepherd's role in the ecosystem, providing a low-cost solution that distinguishes itself from commercial alternatives aimed primarily at real-time flock tracking.

The adaptability of Garut sheep grazing on oil palm and rubber plantations in tropical conditions of Indonesia.

The productivity of sheep in humid tropical plantation areas relies on their ability to adapt. Oil palm plantations serve as potential grazing lands for livestock. This study aimed to identify Garut sheep adaptations in oil palm and rubber plantations of the Garut district, West Java, Indonesia. The total number of sheep used was 103 as the object of this study. Each individual of sheep was used for several different observations, including: Physiological assessment using 24 sheep of various ages, molecular analysis of heat stress using 31 sheep, worm egg count using 59 sheep, and for morphological assessment using 98 sheep. A general linear model was employed to analyze rectal temperature (RT), heart rate (HR), respiratory rate, number of eggs in each gram of sample feces, body weight (BW), body condition score, and morphometric measurements according to age and sex. Forage was compared between oil palm and rubber plantations during the vegetation analysis. RT, HR, and panting frequency were significantly (p < 0.05) affected by the age and sex of the sheep. The mutation was found in the coding region of the HSP70 gene, which is approximately 232 bp long. Fecal eggs were found in 99% of the fecal samples, consisting of 100% Strongyle eggs and 1.75% Moniezia eggs. BW, body condition score, shoulder height, body length, pelvic height, chest circumference, and number of eggs were significantly affected (p < 0.05) by the age and sex of the sheep. The average fresh matter of vegetation under the plantation was 248.69 ± 120.94 g/m2 and 718.15 ± 249.93 g/m2 for oil palm and rubber plantations, respectively. Garut sheep were adapted to oil palm and rubber plantations in the humid tropical region. Plantations are potential sources of sheep grazing and roughage. Further research is needed regarding the consumption of forages in oil palm and rubber plantations.

Predicted methane production from Italian ryegrass pastures with contrasting chemical composition under sheep grazing in Northern Norway

AbstractBackgroundThe Norwegian sheep farming system relies on forages, such as grass silage during winter and grazing cultivated leys and rangeland pastures during summer. Sheep and other ruminants produce enteric methane (CH4), a greenhouse gas of interest, and there is a need for reliable data on gas emissions from sheep capturing both the indoor feeding period and the grazing season. This study utilized an in vitro gas technique (with standard cow rumen fluid) and modeling approach to estimate CH4 production and fermentation patterns based on two different qualities of Italian ryegrass (Lolium multiflorum) pasture under sheep grazing.ResultsHerbage quality was examined for two 10‐day periods, in July and August. Differences in chemical composition of the herbage during these periods had an impact on herbage digestibility and CH4 production. Total gas production and CH4 levels were significantly higher for lower quality herbage grazed in July than for higher quality herbage grazed in August (p &lt; 0.005). Production of volatile fatty acids in the rumen remained constant between the two periods, but the higher acetate to propionate (A/P) ratio correlated with the higher CH4 production.ConclusionThese findings suggest that pasture quality is an important factor to consider when implementing grazing strategies to reduce enteric CH4 production in sheep.

Using the Ecosystem Services assessment tool TESSA to balance the multiple landscape demands of increasing woodlands in a UK national park

Upland regions in the UK are increasingly under consideration as potential areas for the creation of woodlands. This is driven by a combination of factors, including the aims of UK forestry policy to increase woodland cover, changes in current upland land-use and management, agri-environment schemes in national and international policy and an increasing public awareness of the ecosystem service benefits landscapes can deliver for society. Creating new woodlands in upland areas is challenging, partly due to concerns of potential impacts from a change in land use and stakeholder interests. This study considers a 250 km2 Cumbrian (England) upland landscape dominated by sheep grazing and, using an established ecosystem service assessment tool (TESSA), estimates the provision of ecosystem services under plausible alternative woodland creation scenarios. The assessment focuses on key ecosystem goods and services, which are identified by stakeholders to be of high importance to the study area, and the potential changes to those under the scenarios. The results indicate that, under lower woodland percentage scenarios (10 %), minor benefits are expected. However, a more complex outcome would be expected from the higher percentage woodland scenarios (75 %) with the woodland cover of 50 % identified as providing the highest overall benefit to society.

A juhlegeltetési módok hatása a gyepen felvételezhető endoparazita populációra

Sampling for the occurrence of internal parasites of sheep was carried out in three extensively cultivated Achilleo - Festucetum pseudovinae grass communities with different grazing systems but with the same site conditions, in 2022 - 2023, at the MATE Research Institute in Karcag, Hungary. The sheep grazing regimes studied were: pastoral grazing, rotational grazing, and permanent, delta - forest grazing used on all grazing days. Microscopic analysis of the genomes and numbers of potentially infective oviposition and L3 larval stage endoparasites in sheep pastures was carried out on samples of faecal matter from grazed pastures and grass samples prepared using a 'larval feeder'. Our research objective was to clarify the effect of different sheep grazing practices on parasite infestation in a semi - natural grassland community with a solonyec soil composition.

Short‐term grazing reduced community stability by decreasing community‐wide asynchrony and dominant species stability

AbstractThe effects of grazing on natural grasslands' plant composition, diversity, and productivity depend on the intensity of grazing. Besides grazing intensity, animal composition is also important. However, whether and how sheep grazing intensity affects the temporal biomass stability of plant communities is unclear. Here, we conducted a 5‐year grazing experiment to evaluate the effects of four grazing intensities on community biomass stability and the underlying mechanisms. Our results showed that the higher grazing intensity significantly decreased community biomass stability, community‐wide asynchrony, functional groups asynchrony, dominant species stability, and species dominance, but did not affect species richness. The results of structural equation modeling revealed that grazing decreased community biomass stability by decreasing dominant species stability and community‐wide asynchrony, which was attributable to the reduction in plant functional group asynchrony. Our results highlight the importance of functional group composition and dynamics in predicting the changes in community function in sheep grazing grassland ecosystems. Under continuous seasonal grazing conditions, the sustainable function and human services of grasslands in the agropastoral ecotone might decrease in the future.

Socio-Economic Structure, Production Practices, Observations and Suggestions in Nomadic Sheep Production in Ordu province located in Black-Sea Region of Türkiye

Products obtained from farm animals meet the need for animal protein, which has an important place in human nutrition. In recent years, the demand for the products of small ruminants has been increasing. Products obtained from small ruminants are important in meeting the nutritional needs of the world population. Especially in light of the effect of global warming, small ruminants production has become even more important. Especially considering the production conditions of small ruminants, the nutritional needs of animals are met by grazing in the existing highlands. This study was conducted in Ordu province, located in the Black Sea Region of Türkiye. The Black Sea region, with its coasts and springs, is a region where breeders engage in nomadic animal husbandry. In the study, it was determined that 86.6% of the nomadic sheep breeders are producing Karayaka breed sheep while 13.4% are breeding Karayaka crossbreds. In the study, 47.9% of the breeders who participated in the survey live in the village and 45.1% live in the district. Percent 94.4 of the breeders were male and 5.6% were female. It was determined that 32.4% of the breeders were between the ages of 41-50 and 40.8% were primary school graduates. The rate of those who contribute to their livelihood through husbandry is 57.2%. The rate of those who want to continue small ruminant farming in the future is 82.9%. Additionally, it was determined that the majority of breeders attach importance to record keeping and animal health protection practices. In the enterprises where the study was conducted, difficulties were encountered in supplying feed and finding shepherds, and high feed prices and labor costs were stated as the most common problems. In nomadic sheep breeding, grazing and climate parameters in pastures and plateaus have a significant impact on the nutrition of the animals. Therefore, facilitating the transportation of sheep to pastures and plateaus and the sustainability of these areas will positively affect nomadic sheep breeding.

Green-house gas fluxes and soil microbial functional genes abundance in saturated and drained peatlands in South-West Iceland

The drainage of peatlands followed by land use conversion significantly impacts on the fluxes of green-house gases (GHGs, i.e. CO2, CH4, and N2O) to and from the atmosphere, driven by changes in soil properties and microbial communities.In this study, we compared saturated peatlands with drained ones used for sheep grazing or cultivated, which are common in South-West Iceland. These areas exhibit different degrees of soil saturation and nitrogen (N) content, reflecting the anthropic pressure gradient.We aimed at covering knowledge gaps about lack of estimates on N2O fluxes and drainage, by assessing the emissions of GHGs, and the impact of land conversion on these emissions. Moreover, we investigated soil microbial community functional diversity, and its connection with processes contributing to GHGs emission.GHGs emissions differed between saturated and drained peatlands, with increased soil respiration rates (CO2 emissions) and N mineralization (N2O), consistent with the trend of anthropogenic pressure. Drainage drastically reduced methane (CH4) emissions but increased CO2 emissions, resulting in a higher global warming potential (GWP). Cultivation, involving occasional tillage and fertilization, further increased N2O emissions, mediated by higher N availability and conditions favorable to nitrification. Functional genes mirrored the overall trend, showing a shift from prevalent methanogenic archaea (mcrA) in saturated peatlands to nitrifiers (amoA) in drained-cultivated areas.Environmental variables and nutrient content were critical factors affecting community composition in both environments, which overall affected the GHGs emissions and the relative contribution of the three gases.

Bio-guided isolation of a new sesquiterpene from Artemisia cina with anthelmintic activity against Haemonchus contortus L3 infective larvae.

Haemonchus contortus is a blood-feeding gastrointestinal parasite that impacts grazing sheep, causing economic losses in animal production. Due to its anthelmintic resistance, alternative antiparasitic treatments like plant-based anthelmintics are necessary to explore. Artemisia cina (Asteraceae) is a plant whose n-hexane extract and ethyl acetate extract exhibit anthelmintic activity against H. contortus, the n-hexane more active. To discover additional bioactive metabolites, a chemical analysis was performed on ethyl acetate extract, which presented an LC90 of 3.30 mg/mL and allowed the isolation of 11-[(1R,5S,7R,8R,10S,)-1,8-dihydroxy-5,10-dimethyl-4-oxodecahydroazulen-7-yl] acrylic acid. This new sesquiterpene was identified through one and two-dimensional NMR. The compound was named cinic acid and displayed an LC50 of 0.13 (0.11-0.14) mg/mL and LC90 of 0.40 (0.37-0.44) mg/mL, which, compared with ethyl acetate extract larvicidal activity, was 256-fold more active at LC50 and 15.71-fold at LC90. In this study, a new sesquiterpene with larvicidal activity against H. contortus L3 infective larvae was isolated from the ethyl acetate extract of Artemisia cina.

Effects of Sheep Grazing and Nitrogen Addition on Dicotyledonous Seedling Abundance and Diversity in Alpine Meadows

Seedling is a crucial stage in the growth and development of plants, and the expansion and persistence of plant populations can be achieved through seed regeneration. Sheep grazing, fertilization, light, soil moisture, vegetation diversity and biomass, and litter all have potential impacts on species regeneration. We measured vegetation diversity, annual net primary productivity (ANPP), litter, ground photosynthetically active radiation (PAR), and soil moisture of alpine meadows under sheep grazing and nitrogen addition treatments, and studied their effects on the dicotyledonous seedling abundance and diversity using linear regression models (LMs) and structural equation models (SEMs). We found that sheep grazing reduced ANPP, increased vegetation diversity and PAR, and decreased soil moisture. Fertilization increased ANPP and litter, decreased vegetation diversity and PAR, but had no effect on soil moisture. Sheep grazing and fertilization both reduced the abundance of dicotyledonous seedlings, and simultaneously fertilization can reduce the diversity of dicotyledonous seedlings, while sheep grazing had no effect on the diversity of dicotyledonous seedlings. LMs showed that vegetation diversity, ANPP, and litter, rather than light and soil moisture, affected dicotyledonous seedling abundance and diversity. SEMs revealed that sheep grazing and fertilization indirectly influenced seedling regeneration through vegetation diversity rather than ANPP and litter. Our research will increase our understanding of the dicotyledonous plant regeneration process in alpine grasslands and facilitate the development of strategies for management and protection of alpine grassland.