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We assessed the effect of grazing and plant patchiness on the perennial grass seed bank in litter patches in relation to co-occurring shrub, annual grass, and forb seed banks in disturbed rangelands of the Patagonian Monte. We hypothesized that litter patches in disturbed rangelands have a perennial grass seed bank but co-occurring seed banks of annual lifeforms reduce the opportunities for perennial grass reestablishment at these patches. We evaluated the effect of microsite (bare soil vs. vegetated) and grazing (grazed vs, non-grazed) on the (1) size (seeds m−2) of the four seed banks, (2) frequency of microsites with the respective seeds, and (3) frequency of co-occurrence of the perennial grass with shrub, annual grass and forb seed banks in litter patches at 5 dates (2009–2011). We found the smallest perennial grass and annual grass seed banks in litter patches under grazing and in bare soil microsites. The shrub and forb seed banks in litter patches were smaller at vegetated than at bare soil microsites under grazing and the reverse occurred in non-grazed conditions. The sizes of all seed banks were positively related to the frequency of litter patches with the respective seeds. In these litter patches, the size of perennial grass and shrub seed banks did not vary with grazing, and/or microsite while the size of annual grass and forb seed banks decreased with grazing and increased in vegetated microsites. The perennial grass seed bank in litter patches co-occurred mostly with forb and annual grass seed banks (several times larger). This is probably a constraint for the reestablishment of perennial grasses. However, although scarce, litter patches with exclusive perennial grass seed bank or co-occurring perennial grass and shrub seed banks could be an opportunity for perennial grass reestablishment. [ABSTRACT FROM AUTHOR]

Recently, more studies have focused on predicting plant response to livestock grazing by using plant functional traits as indicators to study species adaptation under grazing disturbance. This study examines how different types of plant diversity (taxonomic, phylogenetic, and functional diversity) and strategies (Competitive, Stress-tolerant, and Ruderal) respond to grazing intensity. The study was conducted in the Siah Bisheh Rangelands, located in the southeast of Mazandaran province, Iran. In the region, three adjacent sites were chosen for vegetation sampling. Each site had low and high grazing intensity (LG and HG) areas. For each site and grazing intensity, three 100 m transects were randomly placed. Along each transect, 5 plots (1 × 1 m2) were sampled at 20 m intervals, resulting in a total of 90 plots. The plant coverage was recorded for each plot. To assess the evolutionary relationship among the 76 and 66 species in LG and HG grazing intensities, respectively, a phylogenetic tree was generated. To estimate plant strategy and calculate the overall functional distance between species in this study, four quantitative traits were used: canopy height, leaf area, leaf dry matter content (LDMC), and specific leaf area (SLA). Additionally, three characteristics of CSR strategy classification (Competitive, Stress-tolerance, and Ruderal), were considered. To evaluate functional differences between the two groups with different grazing intensities, we computed functional indices for each sampling plot based on the relative cover of species. The communities subjected to two grazing intensities (LG and HG) were compared using the T-test with a significance level of 5%. The study found that higher grazing intensity caused a shift from the ruderal to the stress-tolerance strategy at both the species and community levels. Furthermore, increased grazing intensity led to a decrease in species richness and diversity, while increasing functional divergence, functional evenness, and community LDMC. Ultimately, stress-tolerant and ruderal strategies dominated under high and low grazing intensities, respectively. The study suggests that plant functional traits are essential in evaluating plant strategies. Analyzing traits like leaf size, SLA, and LDMC can help understand plant survival and growth in different ecosystems. These findings highlight the importance of considering grazing intensity when evaluating plant strategies and the need for further research on how different plant functional traits impact plant responses to grazing pressure. Understanding how various traits contribute to plant performance and ecosystem dynamics can inform decisions about conservation priorities and management strategies. Plant functional traits are a powerful tool for ecologists and conservationists. [ABSTRACT FROM AUTHOR]

BACKGROUND: Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici, is a foliar disease affecting wheat crops against which conventional control methods are not totally effective. During inter‐epidemic periods the fungus survives in wheat residues left on the ground. In this study, we tested the potential of the collembolan Heteromurus nitidus – a springtail species present in field soils and known to interact with different fungal species – as a potential bioregulation agent of Z. tritici on wheat residues through a choice and consumption experiment. RESULTS: Springtails preferred inoculated fresh residues but did not have a preference between inoculated and uninoculated old residues. Springtails grazed on Z. tritici fruiting bodies and reduced pycnidiospore numbers by ten‐fold compared to control inoculated fresh residues. Attraction toward fresh inoculated residues and pycnidiospore reduction support the hypothesis that Z. tritici is a food source for springtails. Heteromurus nitidus showed no preference between inoculated and uninoculated 18‐month‐old residues, probably because they no longer produced ascospores. CONCLUSION: Attraction towards fresh residues and spore reduction support our hypothesis that H. nitidus may contribute to the bioregulation of Z. tritici. Perspectives for field application would be determined by the ability of H. nitidus and Z. tritici to interact at key epidemiological stages. The impact of H. nitidus on the quantity of pathogen primary inoculum over time should be estimated using residues of intermediate age. This would help to identify the optimal period for enhancing the effectiveness of springtails as consumers of Z. tritici. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Beef production is a major contributor to greenhouse gas (GHG) emissions. We conducted a choice experiment to analyse consumers' willingness to pay (WTP) for beef characterised as carbon-friendly. We included a treatment where respondents were informed about carbon-friendly production and surveyed beliefs regarding beef production's contribution to GHG emissions. The results show that consumers have a positive WTP for carbon-friendly beef and providing information increases the premium that they are willing to pay for it. The findings also suggest that consumers who believe that beef production contributes to GHG emissions are willing to pay more for beef carrying a carbon-friendly label. [ABSTRACT FROM AUTHOR]

Our study area, Ejina, is located in the southern Gobi Desert, Inner Mongolia, China, where the annual precipitation is <50 mm and the annual potential evaporation is >3,600 mm. The Heihe River flows from the Qilian Range through the study area, and the desert landscape along the river includes oases formed by forests and grasslands. We established a survey area of approximately 1.5 ha in grassland facing a seasonal swamp, a branch of the Heihe River. We posed the following questions in this desert grassland: (1) how do soil water content (SWC) and salinity change with distance from the riverbank? (2) How do vegetation, aboveground biomass, and species richness change with distance from the riverbank? (3) How much can be supplied to grazing animals, and how many animals can be grazed? Our results indicated that (1) the SWC is high within 20 m of the riverbank and low beyond 20 m, the standing biomass is positively correlated with SWC, but there was no evidence of a correlation between salinity and distance to water; the electrical conductivity was high both inland and adjacent to the riparian swamp. (2) Vegetation could be classified to six classes, following a gradient from the riverbank (swamp margin) to the dry inland area beyond 20 m from the riverbank. Species richness and aboveground biomass were highly correlated. Classification result led us to recommend that generalist species tolerant of the distinct moisture gradient in the site be used in restoration efforts. (3) Per‐hectare aboveground biomass was 478.93 dry weight (dw) kg, 321.2 ha of equivalent grassland would be required to graze 100 goats annually. [ABSTRACT FROM AUTHOR]

In many parts of the world, degradation of grazing lands is one of the most serious environmental issues. This study analyzed farmers' perception of area closure and its associated factors of participation in degraded grazing land restoration in Sede-Muja Woreda, Northwest Ethiopia. A cross-sectional research design and a mixed research approach were applied in this study. The 384 sample respondents were randomly selected. Household surveys, interviews, focus groups, and field study techniques were used to acquire the data. A binary logistic regression model was used to identify the determinant elements that affect farmers' participation in the area closure of degraded grazing land restoration. All of the total respondent farmers (100%) have a positive attitude towards multi-functionality benefits of area closures for local farmers. The model results show that the grazing experience (AOR = 2.981, 95% CI = (1.143-7.775), access to safety net program (AOR = 2.787, 95% CI = (1.146-6.77), access to livestock forage (AOR = 4.493, 95% CI = (1.149-14.028), access to extension service (AOR = 2.522, 95% CI = (1.917-6.6397), livestock ownership (AOR = 0.026, 95% CI = (0.008-0.087), improved cattle breeds (AOR = 4.955, 95% CI = (1.944-12.630), access to training (AOR = 3.169, 95% CI = (1.409-7.131), farmers' perception (AOR = 0.085, 95% CI = (0.023-0.310), and communities' consensus (AOR = 4.230, 95% CI = (1.377-12.996) were determinant factors that affect farmers' participation in the area closure of degraded grazing land restoration. To address the current grazing land degradation issues, every one of the relevant authorities as well as communities needs to work together to create modern grazing land management mechanisms such as grazing land enclosures, reduce animal size through improved cattle breeds, implement zero-grazing systems, and ensure the sustainability of existing enclosures. [ABSTRACT FROM AUTHOR]

Semiarid Patagonia represents 25% of the rangeland area in Argentina, and sheep overgrazing has degraded about a third of it in the past. In this century, depleted domestic stocks have mostly stabilized, but Guanaco populations have grown. These native camelids share habitat and diets with sheep, but their effect on vegetation is poorly understood and has long been debated. We set up an exclusion experiment in Monte León and Cañadón Vaca, a semiarid shrubland grassland in southern Patagonia, currently grazed only by guanacos. Vegetation baselines were studied in 2016 in twelve plots, and half of them were protected from guanaco grazing. Thirty-six plots were cleared to study revegetation. Vegetation was reassessed in 2021, and changes were evaluated using a paired t -test. Within protected plots, vegetation cover increased, bare soil diminished, and vegetated patches grew in size, but the density of the patch-interpatch arrangement did not change. Biodiversity, measured by richness and the Shannon-Wiener (SW) index, grew significantly. Nutrient recycling increased, as did the Stability and Infiltration Land Function indexes, although these last differences were not significant. Vegetation cover under guanaco grazing also increased, mainly due to the growth of dwarf shrubs, a typical tendency in sheep grazing-induced transitions in the region. Vegetated patches under grazing fragmented, resulting in smaller patches and denser patch structures, while diversity and land function indexes remained unchanged. Young plants established in cleared plots without guanacos showed higher cover density and individual size. These effects are similar to those observed in numerous experimental sheep exclosures. Guanaco grazing may thus prevent restoration and contribute to the generalized land degradation processes that overgrazing has been causing in Patagonia for over a century. [ABSTRACT FROM AUTHOR]

African pastoralists suffer recurrent droughts that cause high livestock mortality and vulnerability to climate change. The index-based livestock insurance (IBLI) program offers protection against drought impacts. However, the current IBLI design relying on the normalized difference vegetation index (NDVI) may pose limitation because it does not consider the mixed composition of rangelands (including herbaceous and woody plants) and the diverse feeding habits of grazers and browsers. To enhance IBLI, we assessed the efficacy of utilizing distinct browse and grazing forage estimates from woody LAI (LAIW) and herbaceous LAI (LAIH), respectively, derived from aggregate leaf area index (LAIA), as an alternative to NDVI for refined IBLI design. Using historical livestock mortality data from northern Kenya as reference ground dataset, our analysis compared two competing models for (1) aggregate forage estimates including sub-models for NDVI, LAI (LAIA); and (2) partitioned biomass model (LAIP) comprising LAIH and LAIW. By integrating forage estimates with ancillary environmental variables, we found that LAIP, with separate forage estimates, outperformed the aggregate models. For total livestock mortality, LAIP yielded the lowest RMSE (5.9 TLUs) and higher R2 (0.83), surpassing NDVI and LAIA models RMSE (9.3 TLUs) and R2 (0.6). A similar pattern was observed for species-specific livestock mortality. The influence of environmental variables across the models varied, depending on level of mortality aggregation or separation. Overall, forage availability was consistently the most influential variable, with species-specific models showing the different forage preferences in various animal types. These results suggest that deriving distinct browse and grazing forage estimates from LAIP has the potential to reduce basis risk by enhancing IBLI index accuracy. [ABSTRACT FROM AUTHOR]

Herbivores drive shifts in plant species composition by interacting with vegetation through defoliation, trampling and nutrient addition: urine and faeces. As herbivore effects on vegetation accumulate over time, they might spillover to other trophic levels, but how and when this happens is poorly understood. Since it is methodologically demanding to measure biodiversity across spatial gradients, an alternative approach is to assess it through biodiversity indices of vascular plants. We employed the Index of biodiversity relevance developed for Swedish flora which provides an estimated number of organisms associated with a plant species, allowing the quantification of trophic community size. Values from this index were coupled with vegetation data from a network of 96 fenced and paired grazed plots across Fennoscandia. We analysed the role herbivory has on plant richness and diversity, and on the number of organisms that interact with the vegetation according to the index values. We also explored how herbivores influence the competitive effects of tall shrubs on other plants since the dominance of a vegetation type links directly to biodiversity. Plant diversity had no clear response to grazing. Overall vegetation and the vegetation subgroups herbs and non‐fruit shrubs had higher biodiversity index values in fenced plots, indicating a higher number of plant–host interactions. Herb cover was negatively related to shrubs in both treatments but with a faster decline in the absence of herbivores. This study highlights the importance of maintaining herbivore populations in the Arctic to conserve the vegetation structure and biodiversity of the tundra. This method of coupling biodiversity indexes with vegetation data provides complementary information to the plant diversity, especially when methodological or time constraints prevent complete field inventories. [ABSTRACT FROM AUTHOR]

Introduction: Grassland-livestock balance is an important principle of sustainable development of grassland livestock production and grassland ecosystem health. Grassland degradation becomes more serious at global scales and especially at the area that is sensitive to climate change and human activities. Decreases in pasture biomass and shifts in plant community composition in degraded grasslands can largely affect grazing behaviors of livestock. Up to date, however, it is unclear that whether livestock behaviors change across spatial and temporal scales and what key factors are to shape observed behavioral patterns of livestock. Methods: Here, yak behaviors including grazing, rumination and walking on the eastern Qinghai-Tibetan Plateau (QTP) were monitored by a continuous visual observation, to investigate temporal and spatial variations of grazing behavior of yaks (Bos grunniens); based on the data from public database in the past 18 years, a meta-analysis was conducted to examine the main factors that affect grazing behaviors and intake of yaks. Results: We showed that grazing behaviors of yaks differed significantly within hours, among hours of each day and among days as well as across different observation sites. Intake rate of yaks was higher in the morning than in the afternoon, but walking speed showed an inverse trend compared with intake rate. Resting, altitude, the mean annual precipitation (MAP), the mean annual temperature (MAT), forage ash, yak age and season were the main predictors for yak intake, and forage and yak individual characteristics had direct effects on grazing behaviors and intake of yaks. Discussion: The findings confirm that grazing behaviors of yaks can vary even at small temporal scales and regional scales, which is closely related to the shift in forage quality and biomass caused by environmental changes. The study suggests that multiple factors can be responsible for the variation in livestock behaviors and shifts in behavioral patterns may consequently lead to positive or negative feedback to grassland ecosystems through plant-animal interactions. [ABSTRACT FROM AUTHOR]

Stipa breviflora is a dominant species in the desert steppe of Northern China. Grazing is the main land use pattern of grassland, which could cause a variety of adaptive evolutionary mechanisms in plant community composition as well as individual plant growth and morphological characteristics. However, very little is known about the morphological structure and transcriptional regulation response to different grazing intensities in S. breviflora. In this study, transcriptome and anatomical analyses of S. breviflora under different grazing intensities, including no grazing, moderate grazing, and heavy grazing, were performed. The anatomical analysis results showed that epidermis cells and xylems significantly thicken with grazing intensity, suggesting that grazing results in increasing lignification. Furthermore, the components of cell walls such as lignin, cellulose, hemicellulose, and pectin were all increased dramatically and significantly under both moderate and heavy grazing. Transcriptome analysis showed that the differentially expressed genes related to different grazing intensities were also engaged in plant cell wall formation and in photosynthesis and respiration. In addition, the activities of ATP synthase and Rubisco-activating enzyme increased significantly with enhanced grazing intensity and differed significantly between moderate and heavy grazing intensities. The trends in transcriptome and plant phenotype changes are consistent. Taken together, these results indicated that S. breviflora has evolved a grazing tolerance strategy under long-term grazing conditions, influencing photosynthesis and respiration in terms of its own structure and enzyme activities in the body, to maintain normal life activities under different grazing conditions. [ABSTRACT FROM AUTHOR]

Introduction: Grass-livestock interaction is of great value in maintaining ecological balance, regional economic development, and the sustainability of grassland husbandry, which has gained attention in recent years in both academia and practice, however, study on grass-livestock interaction possesses cognitive bias and gaps. Methods: This study clarified the latest research progress and development trend in the grass-livestock interaction field by illuminating publication trend, cooperative network, keyword co-occurrence relationship, keyword clustering during 2000 to 2022 based on the Web of Science core database. Results: The results indicated that the annual number of publications in the grass-livestock interaction field showed a globally increasing with interdisciplinary and international collaboration, and the United States of America ranked firstly, followed by Brazil, England, Australia, China. Agricultural Research Service, the U.S. Department of Agricultures was the organization with the highest number of publications, and Rangeland Ecology & Management, Agriculture, Ecosystems & Environment, Grass and Forage Science were the top three journals. Furthermore, in terms of the temporal evolution, the research targeting the grass-livestock interaction mainly went through three stages: initial exploration period (2000-2011), to the period of rapid development (2012-2016) to transitional development period (2017-2022), and the notable existing keywords was Management, Livestock, Cattle, Vegetation, Growth, Soil. In terms of the structural composition, four broad divisions including mechanism of human activities, grassland resource monitoring and management, grassland livestock competition/adaptability, grassland land/soil research were identified. The results provide positive and objective insights into that grassland sustainability and grazing control through strengthening crossdisciplinary and cross-regional cooperation, and applying of standard methods based on evaluation system in the grass-livestock interaction field. Discussion: The overall contribution of the work is provision of novel insight into the intellectual structure and temporal progression of grass-livestock interaction research at a macroscopic scale and the directions in which the field is headed currently. [ABSTRACT FROM AUTHOR]

Livestock grazing can strongly determine how grasslands function and their role in the carbon cycle. However, how ecosystem carbon exchange responds to grazing and the underlying mechanisms remain unclear. We measured ecosystem carbon fluxes to explore the changes in carbon exchange and their driving mechanisms under different grazing intensities (CK, control; HG, heavy grazing; LG, light grazing; MG, moderate grazing) based on a 16‐year long‐term grazing experimental platform in a desert steppe. We found that grazing intensity influenced aboveground biomass during the peak growing season, primarily by decreasing shrubs and semi‐shrubs and perennial forbs. Furthermore, grazing decreased net ecosystem carbon exchange by decreasing aboveground biomass, especially the functional group of shrubs and semi‐shrubs. At the same time, we found that belowground biomass and soil ammonium nitrogen were the driving factors of soil respiration in grazed systems. Our study indicates that shrubs and semi‐shrubs are important factors in regulating ecosystem carbon exchange under grazing disturbance in the desert steppe, whereas belowground biomass and soil available nitrogen are important factors regulating soil respiration under grazing disturbance in the desert steppe; this results provide deeper insights for understanding how grazing moderates the relationships between soil nutrients, plant biomass, and ecosystem CO2 exchange, which provide a theoretical basis for further grazing management. [ABSTRACT FROM AUTHOR]

Simple Summary: Our results revealed that the total gas production, CH4 production, and dry matter digestibility reduced significantly as 3NPA doses increased in both yak and cattle. In addition, the H2 accumulation increased significantly in the tubes cultured with 3NPA compared to the control in both yak and cattle. The dynamic profile of total volatile fatty acid (TVFA) production, acetate concentration, and propionate concentration in both yak and cattle at 12 and 24 h incubation was consistent, in which they decreased as 3NPA doses increased, while those for 48 and 72 h incubation were divergent between them. These data demonstrated that the effects of 3NPA on fermentation characteristics between yak and cattle were divergent, and these effects were dose-dependent, and 3NPA regarded as a potential additive to mitigate methane production; although, it inhibits the dry matter digestibility in vitro, which is beneficial to determine the effective and safe dose for use to improve animal productivity in vivo. 3-nitropropionic acid (3NPA) has been proposed as an useful modifier to mitigate ruminal enteric methane emissions. However, few studies investigated the effects of 3NPA on ruminal fermentation characteristics of grazing ruminants in vitro. Rumen fluid from grazing yak and cattle were collected and incubated with additions of 0, 8, and 16 mM 3NPA. The total gas production, CH4 production, and dry matter digestibility significantly decreased with increasing 3NPA doses in both ruminant species (p < 0.05) and methane production decreased to almost 100% in cattle at 8 mM NPA but not yak, while H2 accumulation showed an opposite trend. The total fatty acid (TVFA) production, acetate concentration, and propionate concentration in cattle decreased as 3NPA doses increased at 12 and 24 h incubation. For yak, the H2 accumulation reached its apex at 8 mM NPA (p < 0.05). The TVFA in yak decreased significantly with increasing 3NPA doses at 12 and 72 h incubation. Moreover, the acetate concentration and propionate concentration in yak decreased as 3NPA doses increased at 12 and 24 h incubation. Overall, these findings demonstrated that 3NPA could be used as a strategy to mitigate methane emissions; although, it negatively affected the dry matter degradability in vitro. [ABSTRACT FROM AUTHOR]

Simple Summary: The dry season is the most challenging season for beef cattle grazing. Intensification during the dry season ensures that animal performance is maintained and allows for increases in productivity per area. Thus, the use of concentrated supplementation not only ensures the adjustment of limiting nutrients in the pasture but also allows for the manipulation of the individual and area gain curve. The effects of nutritional strategies associated with supplementation levels and protein sources on the performance, blood parameters, and forage composition of Nelore animals in the rearing phase during the dry period of the year were evaluated. Two protein sources (PS) (soybean meal—SBM and dry distillers grain with soluble—DDGS) and two levels of concentrate (LC) (higher and lower) were tested in the Mombaça grass pastures. Higher levels of concentrate ensure greater productivity for beef cattle grazing. The highest LC increased the total weight gain of beef cattle grazing by 50.5%, while a lower LC increased the leaf/stem ratio (L/S) and crude protein (CP) content of Mombasa grass. The objective of this study was to evaluate the effect of different nutritional strategies on the intensification of beef cattle farming on pastures during the dry period of the year. Eighty male cattle (testers) were randomly allocated to 16 paddocks formed with Mombaça grass (Megathyrsus maximus), totaling five animals (testers) per paddock. The strategies consisted of two LCs [10 and 16.7 g·kg−1 body weight (BW)] and two PSs with DDGS and SBM in a completely randomized design with a 2 × 2 factorial arrangement. The chemical, structural, and productive characteristics of the forage were evaluated, as well as the performance, productivity, and serum parameters of the supplemented animals. The forage presented a greater L:C (p = 0.033) and CP content (p = 0.007) when the lowest LC was used. Animals that received the highest LC had the highest supplement intake (p < 0.001) and the lowest pasture intake (p < 0.001). The nutritional strategy with an LC of 16.7 g·kg−1 of body weight (BW) resulted in a greater increase in total BW, i.e., 200 kg·BW ha−1 more. Therefore, higher levels of concentrate ensure greater productivity for beef cattle grazing, and DDGS can replace SBM in supplements used in the intensive raising of beef cattle on pasture without compromising the performance and productivity of the animals. [ABSTRACT FROM AUTHOR]

Simple Summary: Weaknesses in the sheep meat production chain are largely related to non-specialized systems in the production of this product, which results in the supply of low-quality meat to the consumer market. In this regard, the intensification of animal management is becoming increasingly important. In this study, we evaluated the growth curves of Santa Inês lambs from the suckling phase to weaning to monitor their weight development according to sex and type of birth. Simple and multiple regression equations were evaluated to estimate live weight at weaning. We also found that the best equations for estimating the weight of lambs, regardless of sex and type of birth, were models with more than one biometric measure. However, from a practical point of view, body length and barrel girth can be efficiently used to estimate the weight of Santa Inês sheep at 84 days of age. Monitoring weight development is essential for decision-making and assessing the effectiveness of management strategies. However, this practice is often hindered by the lack of scales on farms. This study aimed to characterize the weight development and growth curves of male and female Santa Inês lambs from birth to weaning, managed on pasture with creep-fed concentrate supplementation. Data from 212 lambs during the pre-weaning phase were analyzed. The animals were weighed every seven days to evaluate total weight gain and average daily gain. Biometric measurements were taken every 28 days. Mixed models were used to assess the effects of sex and birth type on birth and weaning weights. Simple and multiple linear regression models were employed to estimate live weight using biometric measurements. The non-linear Gompertz model was utilized to describe weight development and formulate growth curves. Results were considered significant at p < 0.05. An interaction effect between birth type and sex (p < 0.05) was noted for birth weight, with the lowest weight observed in twin-birth females (2.96 kg) and the highest in single-birth males (3.73 kg) and females (3.65 kg) (p > 0.05). Birth type significantly influenced average daily gain, total weight gain, and weaning weight (p < 0.05). The Gompertz model accurately depicted the growth curves, effectively describing the weight development. Pearson's correlation coefficients between biometric measurements and weight were positive and significant (p < 0.05), ranging from 0.599 for hip height to 0.847 for heart girth. Consequently, the simple and multiple regression equations demonstrated high precision in predicting weaning weight. In conclusion, twin-birth lambs receiving concentrate supplementation via creep-feeding and managed on pasture showed different developmental patterns compared to single-birth lambs under the same conditions. The Gompertz model proved effective for monitoring development during the pre-weaning phase. All simple and multiple linear regression models were effective in predicting weaning weight through biometric measurements. However, for practical application, the model incorporating two measurements—body length and abdominal circumference—is recommended. [ABSTRACT FROM AUTHOR]

Background and Objectives: Surface fires in Iran's natural landscapes are predominantly driven by anthropogenic activities, often deliberately set, and commonly occur either preceding the rainy season or amidst periods of intense heat. These fires are principally conducted to diminish ground-level biomass and modify land utilization practices. The reaction to surface fires diverges among various ecosystems. This study contributes to the ecological resistance and resilience of four distinct plant communities- encompassing shrublands and forests-positioned across an elevation spectrum. Moreover, the study elucidates the impact of grazing-induced stress on the fire response within these communities, offering valuable insights into the intricate interplay between human activities, ecological dynamics, and fire behavior in these environments. Materials and Methods: This study, conducted from 2009 to 2022 in the eastern foothills of the Little Ararat Mountains, focused on four plant communities - Calligonum crinitum, Rhamnus pallasii, Prunus lycioides, and Juniperus excelsa - distributed along an elevation gradient ranging from 800 to 1900 m. Each plant community was divided into grazed and protected areas, within which one or two fire events had occurred. Ecological resistance and resilience were quantified by comparing vegetation cover before and after fire events, as well as the rate of recovery in subsequent years. A general linear model assessed the effects of community type, disturbances (fire and grazing), and fire frequency, while Principal Component Analysis (PCA) examined relationships between vegetation cover, resistance, resilience, and precipitation. Results: The Calligonum community demonstrated the lowest ecological resistance but the highest resilience compared to the other communities. Elevation variations resulted in distinct gradients in both resistance and resilience indices. Notably, the Juniperus community exhibited a significant decline in resistance after an initial elevation-related increase. The protective status of the land did not notably impact differences in ecological resistance across communities. However, protection played a pivotal role in resilience, with protected areas generally displaying higher resilience levels than unprotected ones, except in the Rhamnus community. Fire frequency effects on resistance and resilience varied among communities: resistance decreased after the second fire in the Juniperus and Prunus communities, while other communities showed no significant changes. Regarding resilience, a marked decline was observed in the Rhamnus and Prunus communities after the second fire, whereas the Calligonum and Juniperus communities maintained consistent resilience levels. Spatial distribution mapping of fire-affected samples revealed an overall lack of ecological stability in the study area, with most samples- excluding a few from the Prunus and, to some extent, Juniperus communities-not fully recovering to their initial conditions. PCA results highlighted a strong positive correlation between Calligonum samples and the resilience index. Differentiation among the Juniperus and Rhamnus communities was primarily driven by their associations with resistance and cover vectors, respectively. Prunus community samples exhibited characteristics intermediate between the cover and ecological resistance vectors in the ordination space. Conclusion: In enhancing the resilience of ecological communities, practices like limiting or excluding grazing activities can typically enhance stability. However, developing an effective surface fire management plan necessitates an understanding of the diverse fire response dynamics observed across distinct elevation and vegetation profiles. The Prunus (wild almond) community emerged as a standout in terms of overall sustainability, showcasing commendable levels of resistance and resilience. This emphasizes its aptness for environments prone to fires. Nevertheless, recurrent surface fires can markedly compromise both the resistance and resilience of a community over time, underscoring the critical need for meticulous and strategic fire management approaches. [ABSTRACT FROM AUTHOR]

Disturbances from rodent engineering and human activities profoundly impact ecosystem structure and functioning. Whilst we know that disturbances modulate plant communities, comprehending the mechanisms through which rodent and human disturbances influence the functional trait diversity and trait composition of plant communities is important to allow projecting future changes and to enable informed decisions in response to changing intensity of the disturbances. Here, we evaluated the changes in functional trait diversity and composition of Afroalpine plant communities in the Bale Mountains of Ethiopia along gradients of engineering disturbances of a subterranean endemic rodent, the giant root-rat (Tachyoryctes macrocephalus Rüppell 1842) and human activities (settlement establishment and livestock grazing). We conducted RLQ (co-inertia analysis) and fourth-corner analyses to test for trait-disturbance (rodent engineering/human activities) covariation. Overall, our results show an increase in plant functional trait diversity with increasing root-rat engineering and increasing human activities. We found disturbance specific association with traits. Specifically, we found strong positive association of larger seed mass with increasing root-rat fresh burrow density, rhizomatous vegetative propagation negatively associated with increasing root-rat old burrow, and stolonifereous vegetative propagation positively associated with presence of root-rat mima mound. Moreover, both leaf size and leaf nitrogen content were positively associated with livestock dung abundance but negatively with distance from settlement. Overall, our results suggest that disturbances by rodents filter plant traits related to survival and reproduction strategies, whereas human activities such as livestock grazing act as filters for traits related to leaf economics spectrum along acquisitive resource-use strategy. [ABSTRACT FROM AUTHOR]

Replacement heifers are regularly weighed to assess their health. These data also predict the milk yield in their first lactation (L). The first derivative of the growth curve represents the weight change rate at a given time. It is interesting to use the higher-order derivatives of one biological process, such as growth, to predict the outcome of another process, like lactation. With 78 records of grazing heifers, machine learning was used to predict the L based on variables calculated during the rearing period, from 3 to 21 months of age, every 3 months: body weight (P), first (1D), and second derivative (2D) of an individually modeled Fourier function. Other variables were the age at effective insemination (AI) and the season of the year when the heifer was born (E). The average deviance of the fitted models represented the goodness of fit. The models were trained using 85% of the records, and the fit was evaluated using the remaining data. The deviance was lower for the models including both derivatives in comparison to the models where the derivatives were not included (p = 0.022). The best models predicted the L using data of heifers at six months of age (r2 = 0.62) and the importance of the variables in the model was 35, 28, 21, and 16% for 1D, AI, 2D, and P, respectively. By utilizing this type of model, it would be possible to select and eliminate excess heifers early on, thereby reducing the financial and environmental costs. [ABSTRACT FROM AUTHOR]

The current New Zealand greenhouse gas inventory predictions assume that dairy cows consume pasture only, but the use of supplemental feeds, including concentrates, on New Zealand dairy farms has increased greatly in recent decades. The objective of this study was to evaluate the effect of feeding graded levels of concentrates on methane (CH4) emissions in lactating dairy cows within a pastoral system. Early lactation dairy cows (n = 72) were allocated (n = 18 per treatment) to receive 0, 2, 4 and 6 kg dry matter (DM) of treatment concentrates per day during milking. The cows grazed pasture ad libitum and CH4 emissions were measured in the paddocks using automated emissions monitoring systems called 'GreenFeed'. Gross CH4 emissions (g/d) were similar for cows across the four dietary treatments, while CH4 emissions intensity (g/kg fat and protein corrected milk production (FPCM) and milk solids production) linearly decreased with increasing concentrate inclusion in the diet (P < 0.02). The CH4 intensity decreased linearly (r2 = 0.42) and quadratically (r2 = 0.53) with increasing FPCM production. [ABSTRACT FROM AUTHOR]

This study determined the effect of feeding synthetic zeolite A prepartum to reduce periparturient hypocalcaemia risk on the eating, lying, and activity behaviours of multiparous grazing dairy cows. Animals were randomly allocated to either a Zeolite treatment group (n = 21; individually fed 500 g/d zeolite for two weeks prepartum) or a Control group (n = 22). Behaviour data obtained from accelerometers were analysed to determine the effects of treatment, parity (Parity 2−3 vs. 4+), and their interactions during 3 periods: PRE (−21 to −3 d), PERI (−2–2 d) and POST (3–28 d) relative to the day of calving (day 0). Parity 2–3 Zeolite cows ate for 18 min/day less than Parity 2–3 Control cows PRE. Zeolite-fed cows also ate for 24 min/day less than Control cows during the PERI period. There were no treatment differences in lying time or activity PRE or PERI, but Zeolite-fed cows spent more time lying POST. Regardless of treatment, Parity 2–3 cows were generally more active and ate for longer than Parity 4 + cows. Our results suggest zeolite may subtly decrease appetite or alter eating behaviour during the supplementation period, particularly in younger cows, and may improve cow comfort postcalving. [ABSTRACT FROM AUTHOR]

Urinary nitrogen (UN) excretion and milk production traits of 35 groups of 15 grazing cows each were measured over two years. Urine volume and N concentration were measured with urine sensors and daily UN excretion was calculated for four consecutive days. Milk yield, composition and cow liveweight (LW) were used to estimate daily dry matter intakes (DMI) based on back-calculated animal energy requirements and feed metabolisable energy (ME). Different N fractions in the diet were estimated using laboratory data and protein digestion equations. Mean estimates of N intake and UN excretion were 460 and 227 g N/d, respectively. Urinary-N represented 52% of the N consumed, which aligns with indoor N balance studies. Urinary N excretion was weakly correlated (r = 0.29) with dietary N intake, but moderately correlated (r = 0.63–0.67) with diet N concentration, diet N:ME ratio, and diet effective rumen degradable protein (ERDP). The ERDP balance had moderate to strong correlations with N utilisation efficiency (r = −0.89) and the UN expressed relative to N intake (r = 0.59) and N in milk (r = 0.78). These relationships illustrate the potential of urine sensors and energy-based estimations of intake to assess the influence of dietary management strategies to mitigate UN excretion from grazing animals. [ABSTRACT FROM AUTHOR]

Residual methane emission (RME) is a trait that has previously been identified as being independent of animal production traits. The objective of this study was to investigate the effect of ranking grazing dairy cows by RME on animal productivity and enteric methane (CH4) emissions. Milk production, dry matter intake (DMI), liveweight (LWT) and CH4 were recorded on grazing late lactation dairy cows at Teagasc Moorepark, Ireland. The dairy cows were producing 352 g CH4/day, while consuming 16.6 kg DM. The mean methane yield was 20.79 g CH4/kg DMI. Residual methane emission was calculated as the difference between measured CH4 yield and New Zealand emission factor (21.6 g CH4/kg DMI). These dairy cows were ranked based on their RME and classified into groups. The low RME group produced 15% less CH4 than the high RME group while maintaining milk production and feed conversion efficiency. The low RME group had lower methane yield, and methane intensity. There are no significant phenotypic correlations between RME and animal production traits such as energy corrected milk yield, or LWT. These results indicate that RME has the ability to select and rank low emitting grazing dairy cows while being independent from animal productivity traits. [ABSTRACT FROM AUTHOR]

In this paper, we establish a stochastic dynamical grazing ecosystem with time delays and fluctuations. The effects of time delay, Gaussian noise and Lévy noise on the stationary probability distribution (SPD), the mean first passage time (MFPT) and stochastic resonance (SR) are analyzed. Our research results show the following: (i) For small time delay, the increasing Gaussian noise intensity leads to catastrophic regime shift (CRS) from high vegetation state to low vegetation state, while the increasing Lévy noise intensity contributes to the recovery of these shifts. For large time delay, the increasing Gaussian noise intensity or Lévy noise intensity causes the CRS phenomenon, the larger the time delay, the more frequent the CRS phenomenon. (ii) The increasing Gaussian noise intensity can diminish the stability of the high vegetation state and low vegetation state, the increasing Lévy noise intensity and Lévy stability index can enhance the stability of the high vegetation state and diminish the stability of the low vegetation state. The increasing Lévy noise intensity can lead to noise-enhanced stability (NES) of the high vegetation state, and the larger the time delay, the more pronounced the NES phenomenon. (iii) The increase of time delay can weaken SR phenomenon when signal-to-noise ratio (SNR) is a function of Gaussian noise intensity and Lévy noise intensity. [ABSTRACT FROM AUTHOR]

The grazing impacts of two Acartia species (Acartia omorii and A. steueri) on size-fractionated phytoplankton biomass were measured in Jangmok Bay, Korea (34°59′37.8" N, 128°40′28.2'' E) from January to May 2015. Total chlorophyll (Chl-a) concentrations ranged from 0.66 to 5.18 µg L−1, and micro-phytoplankton (> 20 µm) comprised up to 66% (range, 10.5–65.6%) of the total pigment. The total abundance of Acartia species ranged from 267 to 5931 ind. m−3, and these copepods accounted for 20.8 to 88.0% of the total copepod abundance. The ingestion rates of A. steueri (r2 = 0.904, P = 0.013) and A. omorii (r2 = 0.239, P = 0.046) showed a high correlation with micro-phytoplankton. The average grazing impact of Acartia species on phytoplankton biomass was approximately 6.8 ± 11.8% (range, 0.1–69.0%). Temperature–salinity (T–S) diagram analysis revealed distinct environmental preferences for each species; A. omorii preferred a broader temperature range of 6.2 to 17.1 °C and a salinity range of 31.8 to 33.5, whereas A. steueri was more restricted, preferring temperatures between 6.5 and 12.8 °C and a salinity range of 32.2 to 33.5. These findings not only contribute to our understanding of the ecological roles of these copepod species in marine ecosystems but also highlight the importance of continuous research regarding the mechanisms driving their coexistence and interaction with the coastal food web. [ABSTRACT FROM AUTHOR]

Plant dwarfism, a syndrome characterised by a significant reduction in plant height and organ size, is a widely observed pattern of stress‐tolerant life‐form evolution that results from local adaptation to harsh environmental conditions. The drivers of assemblage‐level dwarfism have primarily been attributed to abiotic factors, such as low temperature, aridity, poor soil fertility or frequent fires. While biotic factors such as grazing pressure from herbivores can contribute to the establishment of plant dwarfism, these factors have rarely been tested at assemblage levels.Focusing on a dwarf plant assemblage comprising over 80 taxa on a small continental island in Japan with a high deer density, we hypothesised that historical deer grazing could also be a factor contributing to the large‐scale convergent evolution of dwarfism.To test this hypothesis, we measured the size of 1908 individual plants of 40 taxa pairs, comprising both palatable and unpalatable pairs from the island and their counterpart taxa from neighbouring regions, and sought to assess which factors (i.e. low solar radiation, estimated divergence time, low nutrient conditions and grazing pressure from deer) may have contributed to the formation of the dwarf plant assemblage on the island. We also performed genetic analysis to infer the time frames for the establishment of dwarf taxa.Statistical analyses revealed that plant size was significantly reduced mainly among the palatable taxa growing on the island, with preferential grazing by deer being identified as the most significant factor influencing plant size. Furthermore, genetic analyses revealed that dwarf ecotypes may have evolved over tens of thousands of years.Synthesis: To the best of our knowledge, this study is the first to demonstrate that interactions with herbivores can shape the assemblage‐level convergence of plant dwarfism. These findings enhance our current understanding of the formation of plant functional diversity. [ABSTRACT FROM AUTHOR]

Grazing affects plant community characteristics and the relationship between above-ground biomass and diversity, which has become a hot topic in grassland ecosystem research in recent years. The present study investigated grassland vegetation in the Two Rivers pastoral area based on 60 sampling points using sampling methods. The effects of grazing on the structural characteristics of plant communities were analysed using the α-diversity index, and the relationship between species diversity and the above-ground biomass of plant communities, as well as their changes, was explored. The results showed that grazing disturbance decreased the number of family species in the grassland plant communities and the similarity between communities; grazing activities significantly decreased the above-ground biomass of the grassland plant communities; the height and cover also showed a decreasing trend (p < 0.01), but the density of the grassland plant communities improved (p < 0.01). The Margalef index, the Shannon–Wiener index, and the Simpson index of the grassland plant communities all showed different degrees of decrease after grazing, while the Alatalo index showed an increase; biomass was positively correlated with the Margalef, Shannon–Wiener, and Alatalo indices and negatively correlated with the Simpson index (p < 0.01). Therefore, in the management and maintenance of grasslands, the impact of grazing on the structural characteristics of plant communities should be taken into account, and reasonable response policies should be implemented according to the actual local situation. This study provides a theoretical basis for grassland maintenance and management and the sustainable development of ecosystems in the pastoral areas of the two river sources of the Altay Mountains. [ABSTRACT FROM AUTHOR]

Scutellaria rupestris subsp. cephalonica (Rech.f.) Greuter & Burdet (Lamiaceae) is a perennial herb endemic to Mounts Ainos and Roudi on the island of Cephalonia. Until now, information about the taxon's distribution has been sketchy: two fairly localized populations on Mt. Ainos have been reported, one of them extinct, and two on Mt. Roudi, without specifics. Because we thought that the taxon is much more common, we designed a survey along contours encircling the two peaks totaling 80 km. We recorded 112 locations of the taxon. We found that S. rupestris subsp. cephalonica prefers sunny clearings within fir forest as well as crevices among limestone rock on somewhat flat terrain. On Mt. Roudi, the taxon grows above 800 m, and is rather uncommon. On Mt. Ainos, the taxon is quite common above 1100 m; below that altitude it has not been confirmed. The findings were more abundant on the NE slope of Mt. Ainos which is wetter and possibly cooler than the SW slope due to being shaded and more forested, less eroded, and with a deep organic layer. The main threat to the survival of the taxon is illegal grazing. The proposed Red List assessment according to IUCN is EN B1ab(iii)+2ab(iii). [ABSTRACT FROM AUTHOR]

Fire and herbivory interact to alter ecosystems and carbon cycling. In savannas, herbivores can reduce fire activity by removing grass biomass, but the size of these effects and what regulates them remain uncertain. To examine grazing effects on fuels and fire regimes across African savannas, we combined data from herbivore exclosure experiments with remotely sensed data on fire activity and herbivore density. We show that, broadly across African savannas, grazing herbivores substantially reduce both herbaceous biomass and fire activity. The size of these effects was strongly associated with grazing herbivore densities, and surprisingly, was mostly consistent across different environments. A one‐zebra increase in herbivore biomass density (~100 kg/km2 of metabolic biomass) resulted in a ~53 kg/ha reduction in standing herbaceous biomass and a ~0.43 percentage point reduction in burned area. Our results indicate that fire models can be improved by incorporating grazing effects on grass biomass. [ABSTRACT FROM AUTHOR]

Hypergolic ignition of H2O2 and MEA-NaBH4 by off-center collision of their droplets was experimentally studied, focusing on the characteristics and mechanism of droplet mixing, droplet heating and evaporation, and gas-phase ignition. The whole collision ignition process was divided into five stages, which were compared, respectively, with that of head-on collision. Under the condition of a slightly off-center collision (for cases where B < 0.35), H2O2 droplets penetrate MEA-NaBH4 droplets after the collision and coalesce with it, but the internal H2O2 drop inside the MEA-NaBH4 droplet does not form a stable sphere. Instead, it rotates and expands inside the mixed droplet. With B increasing to 0.59, the droplets no longer coalesce after collision but separate away, forming satellite droplets. In such cases, multi-ignition mode is observed. When B increases to a certain extent, specifically, 0.85, a grazing collision is observed such that no mass transfer exists during the interaction of droplets, which leads to ignition failure. A theoretical model quantifying droplet swelling rate was established to calculate the volume change of the droplet. It was found that the swelling can be attributed to the flash boiling of superheated internal H2O2 fluid. Meanwhile, the ignition delay time was found to linearly decrease with B at various Wes until the extent where the chemical reaction takes over control, leading to an almost constant time delay defined as RDT. Additionally, the regime of ignition modes corresponding to different droplet mixing features is summarized in the We-B parametric space. [ABSTRACT FROM AUTHOR]

Conservation policy for the high mountains of Asia increasingly recognises the need to encompass large multi‐use landscapes beyond the protected area network. Due to limited long‐term research in this region, our understanding of even fundamental processes, such as factors regulating large mammal populations is poor.Understanding the factors that regulate animal populations, especially those generating cyclicity, is a long‐standing problem in ecology. Long‐term research across multiple taxa (mainly from Europe and North America) has focussed on the relative roles of food and predation in generating cyclicity in population dynamics. It remains unclear how trophic interactions that are influenced by anthropogenic stressors can affect population dynamics in human‐modified landscapes.We present a 10‐year study to compare the effects of livestock grazing on density‐dependent dynamics in two populations of bharal, Pseudois nayaur, in the Himalayas. We combine this with a mechanistic understanding of whether density dependence in these two sites acts predominantly by affecting adult survival or recruitment. We compared and quantified density dependence in the bharal population by fitting Bayesian Gompertz state‐space models.We found evidence for negative density dependence which indicates possible cyclic dynamics in the bharal population of the site (Tabo) with low livestock density. The population dynamics of this site were driven by recruited offspring—with a 2‐year density‐dependent lag effect—rather than adult survival. In the site with high livestock density (Kibber), this density dependence was not detected. We postulate the potential role of excessive grazing by livestock in affecting offspring recruitment, thereby affecting the bharal population in Kibber.Synthesis and applications: Our results suggest that conservation action to facilitate wild herbivore population recovery, such as the development of protected areas and village reserves, needs to account for density‐dependent regulation. Sites with trophy hunting require continuous monitoring to understand the effects of density dependence so that appropriate hunting quotas can be formulated. [ABSTRACT FROM AUTHOR]

Grazing management and nitrogen fertilisation may affect forage accumulation (FA), nutritive value, and grazing efficiency (GE) of the highly productive 'Zuri' guineagrass [Megathyrsus maximus (Jacq.) B.K.Simon & S.W.L. Jacobs syn. Panicum maximum Jacq.]. The objective of this study was to assess the effects of pre‐graze canopy heights [55 and 75 cm (H55 and H75, respectively)] and N fertilisation rates [150 and 300 kg N ha−1 year−1 (N150 and N300, respectively)] on FA, GE, grazing losses (GL), and nutritive value of Zuri under rotational stocking. The stubble height was 50% of the pre‐graze canopy height. The total FA was 20% greater under H75 than H55 (22,120 vs. 18,370 kg DM ha−1 year−1), as well as the GL was greater under H75 (85%) than under H55 (79%). Regardless of pre‐graze height, the upper stratum of the canopy was composed mostly of leaves contributing to similar crude protein (CP) (142 g kg−1) and in vitro digestible organic matter (IVDOM) (559 g kg−1) concentrations. Greater N rate (N300) increased FA (23,500 vs. 16,980 kg DM ha−1 year−1) and resulted in greater GE (84% vs. 80%) compared to N150. The CP and IVDOM concentrations under N300 (157 and 571 g kg−1, respectively) were greater than under N150 (128 and 547 g kg−1). Zuri guineagrass grazed at H75 has great FA and GE, maintaining a similar forage nutritive value compared to H55. [ABSTRACT FROM AUTHOR]

Grazing lands can be considered a conservation land use providing value to farmers and society. An underappreciated value of these lands may be in C and N storage and cycling. However, soil organic C (SOC) and total soil N (TSN) storage under humid‐temperate zone pastures have not been well characterized. A survey of 31 farms in Virginia USA characterized SOC and TSN depth distributions under a diversity of grassland management scenarios, as well as in comparison with long‐term no‐till cropland and woodland uses on the same farms. Root‐zone enrichment calculations separated management‐controlled SOC and TSN stocks from a baseline condition characterized at 30‐cm depth. Total stock of SOC at 0–30‐cm depth varied from 46 to 88 Mg C ha−1 (5%–95% range from 304 soil profiles) across all land uses. Root‐zone enrichment of SOC was maximized under mature pastures (≥20 years old) at 38.3 ± 1.6 Mg C ha−1, which was not different from that under woodland (39.8 ± 1.2 Mg C ha−1), but was greater than under no‐till cropland (28.3 ± 1.3 Mg C ha−1) and conventional‐till cropland (15.1 ± 5.1 Mg C ha−1). Root‐zone enrichment of TSN was optimized at stocking rate of ~1 Mg live weight ha−1, but was not affected by stocking method, N fertilization history, or low levels of hay feeding. These results suggest that grazed pastures in Virginia are storing significant amounts of SOC and TSN, with at least half due to management‐induced compared with pedogenic‐controlled accumulation. [ABSTRACT FROM AUTHOR]

Incorporating native forbs within native warm‐season grass (NWSG) pastures has the potential to benefit cattle, pollinators, and wildlife beyond that of NWSG monocultures. However, when grazing NWSG pastures, rotational stocking is recommended as opposed to continuous stocking. Therefore, to evaluate whether within‐season rest is needed for native pasture sustainability, two NWSG grazing experiments were conducted near Greeneville, TN, 2017–2020, to assess the persistence of native forbs when an 11‐species native forb blend was interseeded into established switchgrass (SG; Panicum virgatum L.) and big bluestem/indiangrass (BBIG; Andropogon gerardii Vitman and Sorghastrum nutans (L.) Nash) pastures. Each experiment was a completely randomized design with four replicates of each within‐season rest grazing treatment (no rest, early rest, middle rest, late rest, and no graze). Within‐season rest was not influential for NWSG tiller density or total forb plant density thus indicating persistence of forbs may not require rotational stocking. Purple prairie clover (Dalea purpurea Vent.) did not establish while Illinois bundleflower (Desmanthus illinoensis (Michx.) MacMill. ex B.L. Rob. & Fernald) was only observed flowering once despite having the greatest seeding rate among forbs. Based on establishment and flowering of the 11 species in the current mixture, interseeding a 6‐species polyculture of black‐eyed Susan (Rudbeckia hirta L.), dixie ticktrefoil (Desmodium tortuosum (Sw.) DC.), eastern purple coneflower (Echinacea purpurea (L.) Moench), lanceleaf coreopsis (Coreopsis lanceolata L.), Maximilian sunflower (Helianthus maximiliani Schrad.), and oxeye sunflower (Heliopsis helianthoides (L.) Sweet) could allow for plant biodiversity while offering floral resources for pollinators during the NWSG grazing season. [ABSTRACT FROM AUTHOR]

Urine patches from grazing ruminants contain high concentrations of nitrogen (N) and are the main source of N leaching from grazed pastoral farming systems. While there have been various options identified to substantially reduce N leaching, in general these practices increase the cost of production or reduce production per hectare. In New Zealand, multi‐species pastures were evaluated as a cheaper option that would potentially retain productivity. Early research showed these pastures had lower urinary N excretion from grazing animals and increased plant N uptake, compared with standard New Zealand perennial ryegrass/white clover (PR‐WC) pastures. Further research highlighted the beneficial attributes of the pasture herb narrow‐leaved plantain (Plantago lanceolata; PL), specifically: reduced urine N concentration, reduced urine N excretion, and reduced rate of soil nitrification. Significant reductions (14%–89%) in N leaching were found from cow urine applied to lysimeters with pastures including PL, compared with PR‐WC pasture. Paddock‐scale measurements confirmed the effects of PL, with 20%–60% lower N leaching when PL comprised 30%–40% of the dry matter (DM) of PL‐PR‐WC grazed pastures. There were no negative effects on milk production and composition when feeding PL to dairy cows, but small positive effects on fatty acid profiles. However, weed and pest management, palatability and persistence remain challenging in pastures containing PL on commercial farms. Management options need to be clarified to ensure successful establishment and maintenance of PL. Additionally, the cultivar differences in secondary compounds and their impact on nitrification rate and N leaching need to be better understood. [ABSTRACT FROM AUTHOR]

The specialisation of agricultural systems in Western Europe and the intensification of livestock and cropping production are intrinsically linked to substantial resource inputs. This intensified approach frequently leads to nutrient surpluses and biodiversity loss, resulting in detrimental environmental impacts. A transformative agricultural shift is imperative in light of climate and environmental protection objectives. Addressing this need, the Lindhof eco‐efficient pasture‐based milk production initiative, initiated in 2016, is a tangible manifestation of a productive and profitable dairy system integrated within a ley‐based Integrated Crop‐Livestock System (ICLS). Operational at the organically managed Lindhof farm, this approach involves a rotational stocking system of spring‐calving Jersey cows stocked on grass‐clover‐herb leys embedded within a cash crop rotation. The dairy cows benefit from these highly productive swards, rich in nutritive value comparable to concentrate feeding. At the same time, the cultivated crops derive advantages from the legacy effect of leys due to nutrient exchange facilitated by grazing excreta and residual crop matter. Compared to specialised systems, the ley‐based ICLS emerges as an alternative dairy production paradigm that supports many ecosystem services – including minimised nutrient losses, a lower carbon footprint and positive contributions to agro‐biodiversity. These outcomes are realised without compromising overall land‐use efficiency while reducing environmental and social costs of 20–30 Eurocent per kg of milk produced compared to specialised systems. Thus, the ley‐based ICLS conforms to the principles of ecological intensification, enhancing functional diversity within the agricultural landscape. Essentially, the Lindhof initiative represents a holistic and environmentally responsible approach to farming that could contribute to realising the EU Farm to Fork Strategy. [ABSTRACT FROM AUTHOR]

Simple Summary: Several studies with Bos taurus cows report a decrease in voluntary intake close to parturition. However, there are few studies on the evaluation of these parameters in grazing Nellore cows receiving protein supplementation, which could mitigate the decrease in forage intake and improve animal performance. Hence, this study sought to understand how the feed intake and performance of Nellore cows on pasture changes during the peripartum period. Our study found a significant reduction in cows' voluntary intake as they approach parturition, which provides a rational approach to supplementing pregnant cows at the end of gestation, improving production rates in calf–cow systems in the tropics. We aimed to understand the changes in nutritional parameters and performance of beef cows during the peripartum, whether receiving or not receiving protein supplements. Forty cows were used, divided into two treatments: CON—mineral mix and SUP—protein supplementation. Digestibility trial was performed at 45, 30, and 15 days (d) before the parturition and at 20 and 40 d of lactation. The ADG of cows pre- and postpartum was recorded along with the BCS in gestational (GT) and maternal (MT) tissues in the prepartum. There was an effect of treatment and period (p ≤ 0.044) for intakes of DM and CP. The forage intake was similar (p > 0.90) but varied with the effect of days related to parturition (p < 0.001). There was a 14.37% decrease in DM intake from d −30 to d −15 of prepartum. In the postpartum, at 20 d of lactation, there was an increase of 72.7% in relation to d −15 of prepartum. No differences were observed in postpartum ADG or BCS at parturition and postpartum (p ≥ 0.12). However, higher total and MT ADG (p ≤ 0.02) were observed in animals receiving supplementation, while ADG in GT remained similar (p > 0.14). In conclusion, there is a decrease in intake for pregnant cows close to parturition and greater performance of animals supplemented in prepartum. [ABSTRACT FROM AUTHOR]

Prokaryotes play a fundamental role in global ocean biogeochemical cycles. However, how the abundance and metabolic activity of ecologically distinct subgroups (i.e., high nucleic acid (HNA) and low nucleic acid (LNA) cells), and their regulating factors, change in response to changing marine environmental conditions remains poorly understood. Here, we delved into the time-evolving dynamic responses of the HNA and LNA prokaryotic subgroups to declining resource availability and selective grazing by protozoa by conducting a 73-day incubation experiment in a large-volume (117,000 L) macrocosm that facilitates community-level exploration. We found that the metabolic activity of the HNA subgroup was higher than that of the LNA subgroup when the macrocosm was resource replete but that the HNA subgroup declined more rapidly than the LNA subgroup as the resources became increasingly scarce, leading to a steadily increasing contribution of LNA cells to prokaryotic activity. Meanwhile, as resources in the macrocosm became limited, protozoan grazing preference shifted from the HNA to the LNA subgroup and the contributions of the LNA subgroup to the carbon flow within the macrocosm increased. The findings highlight the resilience of LNA cells in resource-limited environments, illuminate the critical role of selective grazing by protozoa in balancing distinct prokaryotic subgroups under changing resource conditions, and demonstrate the complex and adaptive interactions between protozoa and prokaryotes across diverse environmental contexts. [ABSTRACT FROM AUTHOR]

Leatherjackets (Tipula spp.) are soil‐dwelling pests associated with agriculture. Land management decisions made at farm scale can have subsequent effects on their populations. Between 1980 and 2020, surveys were conducted across Scotland to collect field histories and larval population data from grassland farms. To assess the impact of management and bioclimatic factors on leatherjacket occurrence over time, this study investigated data from fields continuously sampled between 2009 and 2018. We utilized a Generalized Linear Mixed‐Effect Model on a dataset of 61 fields on 19 farms. Results indicated three significant factors affecting larval populations; field size, grazing type and application of insecticides or herbicides (referred to collectively as pesticides). Larval populations were significantly lower in fields that were larger in size and under sheep grazing, compared to no grazing. Pesticide application also caused a significant reduction in larval populations. Management variables were amalgamated to create a Management Intensity Index, revealing significantly increased larval populations under low‐management systems. These results, coupled with significant effects of bioclimatic variables, pinpoint predictive signals for high infestations and potential routes for control strategies. [ABSTRACT FROM AUTHOR]

Qinghai−Tibetan Plateau (QTP) is the largest contiguous grazing area in the world, while its soil has a low soil selenium (Se) content, an essential rare element for human health. Grazing and Se addition are two common management practices in the regional grasslands, but their interactions with the vegetation growth of alpine meadows in the QTP remain largely unknown. Here, we conducted a two−year field experiment (2017 and 2018) to explore the effects of grazing [two stocking rates (0 and 6 sheep months ha−1)] and Se addition [six Se addition levels (0, 5, 10, 20, 40 and 80 g ha−1)] on above−ground biomass (AGB), below−ground biomass (BGB), root−to−shoot ratio (R/S), species richness and Shannon−Wiener's diversity index of an alpine meadow at the Maqu county in the Eastern QTP. The results indicate that AGB peaked at a Se addition rate of 21 g ha−1 combined with no grazing (i.e., exclosure) and at a rate of 20 g ha−1 Se addition with a stocking rate of 6 sheep months ha−1; BGB was highest under a Se addition of 23.5 g ha−1 (under exclosure) and 23 g ha−1 (under grazing). After Se addition, the species richness and Shannon−Wiener index of the alpine meadow under the grazing treatment were significantly lower than those in the exclosure treatment, which was mainly driven by the reduction of sedges and forbs. The structural equation model showed that grazing reduced the biomass of sedge, gramineae, and forbs, while Se addition increased the soil available nitrogen and phosphorus content and promoted the growth of sedge, gramineae, and forbs. Our results suggested that moderate grazing combined with Se addition is a suitable management method for maintaining alpine meadow productivity. [Display omitted] [ABSTRACT FROM AUTHOR]

Exotic annual grass invasion is a widespread threat to the integrity of sagebrush ecosystems in Western North America. Although many predictors of annual grass prevalence and native perennial vegetation have been identified, there remains substantial uncertainty about how regional‐scale and local‐scale predictors interact to determine vegetation heterogeneity, and how associations between vegetation and cattle grazing vary with environmental context. Here, we conducted a regionally extensive, one‐season field survey across burned and unburned, grazed, public lands in Oregon and Idaho, with plots stratified by aspect and distance to water within pastures to capture variation in environmental context and grazing intensity. We analyzed regional‐scale and local‐scale patterns of annual grass, perennial grass, and shrub cover, and examined to what extent plot‐level variation was contingent on pasture‐level predictions of site favorability. Annual grasses were widespread at burned and unburned sites alike, contrary to assumptions of annual grasses depending on fire, and more common at lower elevations and higher temperatures regionally, as well as on warmer slopes locally. Pasture‐level grazing pressure interacted with temperature such that annual grass cover was associated positively with grazing pressure at higher temperatures but associated negatively with grazing pressure at lower temperatures. This suggests that pasture‐level temperature and grazing relationships with annual grass abundance are complex and context dependent, although the causality of this relationship deserves further examination. At the plot‐level within pastures, annual grass cover did not vary with grazing metrics, but perennial cover did; perennial grasses, for example, had lower cover closer to water sources, but higher cover at higher dung counts within a pasture, suggesting contrasting interpretations of these two grazing proxies. Importantly for predictions of ecosystem response to temperature change, we found that pasture‐level and plot‐level favorability interacted: perennial grasses had a higher plot‐level cover on cooler slopes, and this difference across topography was starkest in pastures that were less favorable for perennial grasses regionally. Understanding the mechanisms behind cross‐scale interactions and contingent responses of vegetation to grazing in these increasingly invaded ecosystems will be critical to land management in a changing world. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Improvements in animal husbandry environment have resulted in major benefits to dairy farming in tropical regions. The aim was to evaluate the effect of changes in sun/shade regimes—restricted shade (RSR), moderate shading (MSR), and intense shading (ISR)—on the behavior of crossbred dairy cows. Massai grass with eucalyptus trees were used in the system. The experiment was conducted at Brazil from 2017 to 2018. Eight dairy cows were observed in each regime over three days by seasons every 30 min from 6 a.m. to 6 p.m. The behavioral variables considered were localization, posture, and activity. Microclimatic variables were studied and hourly averages were calculated for seasons. The experiment was conducted in randomized complete blocks with split-plots; evaluation times were allocated to subplots and sequential days of analysis were considered replications in time. Multivariate analysis (principal component analysis) was performed using Excel. The results showed that the RSR had a higher proportion of idle cows, which was associated with a higher intensity of radiation (1.2 MJ m−2 h−1). The MSR and ISR differed in radiation levels by 17% and 58%, respectively. The opposite was true when shade was available, as cows performed activities such as grazing more frequently, mainly in the morning shift (difference of 20.7% in the RSR for the shade regime). The behavior of crossbred dairy cows subjected to climatic stress environments was benefitted from microclimatic conditions provided by trees. The provision at least moderate shade around the paddocks, alleviates the stress and regulates the vital activities of the animals. [ABSTRACT FROM AUTHOR]

Previous studies have revealed that mixotrophs can become more heterotrophic as the temperature rises, although these studies were primarily conducted under laboratory conditions with temperature-acclimated grazers. This study investigated the short-term thermal regulation of grazing and photosynthetic performance, measured in terms of the maximum relative electron transport rate (rETRmax), of natural Karenia brevis populations on cultured Synechococcus. Bloom waters were collected in Sarasota, Florida, during the fall of 2022. Synechococcus were inoculated into K. brevis bloom waters in varying ratios and incubated at an ambient temperature and an ambient temperature ±5 °C (19, 24, and 29 °C). In general, the grazing coefficient, clearance, and ingestion rates were higher in warmer waters, although ingestion rates were significantly regulated by the prey-to-grazer ratios and, to a lesser degree, by temperatures (22 to 204 Synechococcus K. brevis−1 d−1). Overall, the rETRmax of Synechococcus controls generally increased over time with a more substantial increase at warmer temperatures, but, in the presence of grazers, the rETRmax of Synechococcus did not increase, and, remarkably, even decreased in some cases. These findings suggest that grazing on Synechococcus could directly regulate Synechococcus concentrations and indirectly reduce the photosynthetic performance of prey. Furthermore, this study demonstrates that the thermal regulation of grazing and photosynthetic performance can occur on a short-term basis. [ABSTRACT FROM AUTHOR]

The greenery of floodplain meadows in arid regions, such as Mongolia, is influenced by climate, hydrology, and land use. In this study, we analyzed the NDVI (Normalized Difference Vegetation Index) of two floodplain meadows located along the South Tamir and Tamir Rivers using LANDSAT images. Our goal was to observe NDVI spatial changes, variations, and mean values in mid-August every six years from 1991 to 2015 and to identify the factors driving these differences. To achieve this, we conducted variance analysis to identify changes in NDVI and implemented Principal Component Analysis to determine the influence of hydro-meteorological factors and grazing intensity. Our findings indicate a significant decrease in greenness, as measured by pixel-scale NDVI, during the late summer period. This decrease was consistently observed, except for a series of harsh winters that followed relatively dry summers, resulting in a disastrous event called dzud, which led to the death of livestock. The decrease in NDVI was amplified by lower precipitation in June, higher temperatures and wind speed in July, and increased precipitation in August, along with a higher frequency of days with convective rain. Our findings have important implications for managing grazing in Mongolia's grasslands, promoting sustainable land use, and mitigating sandstorms. The variance and average values of NDVI at the pixel level can serve as reliable markers of sustainable pasture management in areas where other vegetation measures are limited. [ABSTRACT FROM AUTHOR]

Seasonal grazing is a recognized and sustainable approach to livestock management, but there is still a lack of comprehensive research on its impact on soil structure. This study utilizes advanced scanning electron microscopy technology to quantitatively evaluate the long-term effects of seasonal grazing on grassland soil structure, focusing on soil pore distribution characteristics and particle size. The investigation offers a detailed visual representation of the arrangement of soil particles at a micro-level. In both grazed and ungrazed plots (NG), soil particles ranging from 0.005 to 0.05 mm and 0.075 to 0.25 mm in size were predominant, constituting 20% and 60%, respectively. In plots subjected to seasonal grazing (grazing in June and August, G68, and grazing in July and September, G79), micro-particles (0.002–0.005 mm) and particles sized 0.05–0.075 mm were significantly lower compared to NG. Scanning electron microscope (SEM) images demonstrate structural differences, with NG displaying a higher proportion of small to medium-sized particles, more small pores, and fewer large pores. Analysis of pore size and morphology reveals the prevalence of large pores in both grazed and ungrazed plots. Continuous grazing plots exhibit significantly higher proportions of large pores compared to NG, while seasonal grazing plots show no significant differences. Correlation analyses indicate associations between soil physicochemical properties, particle size, and pore structure. Total soil nitrogen (TN), total soil carbon (TC), and soil moisture positively correlate with 0.005–0.05 mm particle proportions, while EC is negatively correlated with 0.05–0.075 mm particles. This study enhances our understanding of the effects of grazing practices on soil structure and provides scientific evidence for sustainable land management. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to evaluate an alternative for feeding with silage to limit the decrease in productivity in dry seasons for sheep producers. Design/methodology/approach: Ensilage was made with marafalfa grass (Pennisetum purpureum Schum) and endemic mucuna (Stizolobium pruriens (L.) Medik). The feeding method evaluated consisted of a semi-confined system, allowing the sheep to graze for a period of five hours per day, to later supplement it with the proposed silage. Studies of bromatological parameters were carried out with the three proposed silage treatments, and the weight of the sheep was measured at the beginning, during and at the end of fattening. Results: The results suggest that the P. purpureum silo demonstrates significant weight gain, which is why it is proposed as an alternative for dry seasons. Limitations on the study/implications: In the state of Campeche, sheep production is carried out under extensive direct grazing systems on grasslands, with scarce technology and low productivity. In the dry season, the productivity of these systems suffers a significant loss, due to limitations. Findings/conclusions: Ensilage without the addition of mucuna (S. pruriens) obtained better results in sheep growth and this may be due to palatability. It is suggested to include a drying process prior to adding the mucuna (S. pruriens). [ABSTRACT FROM AUTHOR]

In Canada, new forage varieties need not undergo grazing trials before registration and sale. To evaluate the effect of grazing, six cool-season species including meadow bromegrass (Bromus riparius Rehmann), orchardgrass (Dactylis glomerata L.), sainfoin (Onobrychis viciifoila Scop.), and three alfalfa varieties (Medicago sativa L.) were established in monocultures and grass–legume binary mixtures in Saskatchewan, Canada. Forage treatments were randomly established within each of three 3.5 ha paddock replicates. In Year 1, 69 Bos taurus crossbred steers, and in Year 2, 149 steers were homogenously allocated to the three paddocks for the grazing trials. Alfalfa monocultures had the greatest (p < 0.05) pre-graze forage yields and crude protein content. Leaf area index was greater in alfalfa monocultures than in all other treatments (p < 0.01). Etiolated growth differed (p < 0.05) among binary mixtures but not monocultures. Alfalfa monoculture stands were preferred over grass monocultures and most grass–legume mixtures, and sainfoin was avoided relative to alfalfa. Killarney orchardgrass was the least productive and least preferred among forages evaluated. In summary, alfalfa monocultures had greater (p < 0.05) forage yields and quality than sainfoin monocultures, grass–legume binary mixtures, or grass monocultures. [ABSTRACT FROM AUTHOR]

Studies on the effects of grazing disturbances in grasslands have shown mixed results for spider diversity, mainly regarding their guilds. While ungrazing, low, and moderate grazing potentially enhance the diversity of orb-weavers in spider communities, heavy grazing seems to reduce species' richness. On the population level though, studies of orb-weavers are scarce, and the effects of grazing in natural grasslands are unknown. In this way, we investigated the effects of different grazing levels on population persistence of orb-weaver spiders, hypothesizing that low to intermediate disturbances benefit populations. We predict that high grazing, due to the removal of vegetation structure, will negatively affect the occupancy and abundance of orb-weavers. For that, we experimentally controlled grazing pressure and obtained population occurrence and counts of two orb-weaver spider species, Argiope argentata and Alpaida quadrilorata. We found that A. argentata was negatively affected by grazing, as it relies on higher vegetation for web-building. In contrast, A. quadrilorata, which occurs in cattle-resistant rosette plants, showed no effects of grazing. Implications for insect conservation: Our study emphasizes the need for balanced grazing practices and habitat conservation to protect orb-weaver spiders and other arthropods, as well as species-specific effects for species from the same guild, underscoring their ecological significance in maintaining ecosystem stability. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate rumen fermentation parameters influenced by both grazing system and breed. Materials and Methods: A 2 × 2 factorial design was employed, involving 40 cows with matched age, parity, and physiological status. The cows were evenly divided between Bonsmara and Nguni breeds, as well as communal and commercial grazing systems. Rumen fluid samples were collected and analyzed for parameters including ammonia-nitrogen (NH3-N), pH, temperature, and volatile fatty acids (VFAs). Results: Nguni cows exhibited significantly higher ruminal NH3-N levels (p < 0.05) compared to Bonsmara, ranging from 69.05 to 96.78 mg/l. Commercial grazing demonstrated significantly higher NH3-N concentrations (p < 0.05) than communal grazing. Ruminal pH, temperature, total VFAs, and specific VFAs (Iso-butyrate, valeric, and iso-valeric) did not show significant differences (p > 0.05). However, total VFAs were slightly lower in communal grazing (78.87 mmol/l) than in commercial grazing (89.80 mmol/l). Acetate, propionate, butyrate, and the acetate to propionate ratio did not display significant differences (p > 0.05) between breeds but varied between grazing systems. Communal systems had higher acetate and acetate to propionate ratio (p < 0.05), while commercial systems showed higher propionate and butyrate levels (p < 0.05). Conclusion: Grazing conditions significantly influenced rumen fermentation parameters, irrespective of breed. Further research is necessary to explore the relationship between forage conditions, diversity, and rumen fermentation within different grazing systems. [ABSTRACT FROM AUTHOR]