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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]

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]

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]

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]

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]

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]

The impact of grazing pressure on ammonia oxidizers (AO) has never been quantified in the field. Here we develop a new method to quantify the grazing rates on AO in aquatic systems. We introduce 15NH4+ tracer into the traditional dilution experiments to measure AO's apparent growth rates by using the end‐product of 15NH4+ oxidation, that is, 15NOx−. Field studies in the North Pacific revealed that 15NOx− in the end‐product was sensitive enough to detect AO's grazing rates. Experiments from the lower euphotic zone showed NH4+ replete growth rates of 0.40 d−1 and 0.77 d−1 of AO and in situ grazing rates on AO of 0.41 d−1 and 0.45 d−1, respectively, indicating a strong top‐down control by grazing on AO. Compiled data show a vertical decoupling between ammonia oxidation rates and AO abundance within the euphotic zone, indicating that strong grazing may have affected the distribution of AO in the global ocean. Plain Language Summary: Grazing by zooplankton exerts important control on microbes in the aquatic systems. Ammonia oxidizers (AO) are chemoautotrophic microorganisms that utilize most of their substrate as a source of energy rather than biomass (low biomass yield but high transformation efficiency) and mediate nitrification, a critical process in biogeochemical cycles. Due to the technical difficulty of differentiating AO from other microbes and calculating their change in abundance, the influence of grazing on the AO population in the field has never been quantified. Here we develop a new method that introduces a highly sensitive isotope‐tracing technique into traditional dilution experiments to focus on functional chemoautotrophic AO and quantify their NH4+‐replete growth rates and rates of grazing on them. We found our method to be effective, and for the first time, we revealed that grazing induced a strong top‐down control on AO at the base of the euphotic zone in the North Pacific Ocean. This influence could also be the reason for the vertical decoupling of the ammonia oxidation rate and AO abundance globally. We therefore suggest a wider exploration of grazing influence on AO in field experiments for a deeper understanding of the role of grazing in the marine nitrogen cycle. Key Points: A method that introduced 15NH4+ isotope tracers into dilution experiments is developed to quantify the grazing rate on ammonia oxidizersField experiments showed that grazing consumed more than half of ammonia oxidizer daily growth at the base of the euphotic zone in the North PacificThe strong top‐down control may be widespread to shape the distributions of ammonia oxidizers in the global ocean [ABSTRACT FROM AUTHOR]

Ciliate interactions including mode of nutrition contribute significantly to freshwater and marine ecosystems. Ciliates associations with their bacterial communities, and symbionts have crucial contributions to biomass productivity, transfer of nutrients to higher trophic levels and thus to sustain the ecosystems. The mixotrophic and heterotrophic ciliates are crucial in nutrient cycling by increasing nitrogen, phosphorus, and sulphur. Bacterial predator ciliates regulate the bacterial population and function as bioindicators. Endosymbionts in ciliates illustrate the incorporation of photosynthesis, nitrogen fixation and recycling, and methanogenesis, into ciliate hosts by endosymbionts. Endosymbiosis represents an evolutionary strategy of protists to acquire novel biochemical functions. Herein, I briefly give an account for the impact of ciliate nutrition on aquatic systems. [ABSTRACT FROM AUTHOR]

Background: Grazing exclusion is an efficient practice to restore degraded grassland ecosystems by eliminating external disturbances and improving ecosystems' self-healing capacities, which affects the ecological processes of soil-plant systems. Grassland degradation levels play a critical role in regulating these ecological processes. However, the effects of vegetation and soil states at different degradation stages on grassland ecosystem restoration are not fully understood. To better understand this, desert steppe at three levels of degradation (light, moderate, and heavy degradation) was fenced for 6 years in Inner Mongolia, China. Community characteristics were investigated, and nutrient concentrations of the soil (0–10 cm depth) and dominant plants were measured. Results: We found that grazing exclusion increased shoots' carbon (C) concentrations, C/N, and C/P, but significantly decreased shoots' nitrogen (N) and phosphorus (P) concentrations for Stipa breviflora and Cleistogenes songorica. Interestingly, there were no significant differences in nutrient concentrations of these two species among the three degraded desert steppes after grazing exclusion. After grazing exclusion, annual accumulation rates of aboveground C, N, and P pools in the heavily degraded area were the highest, but the aboveground nutrient pools were the lowest among the three degraded grasslands. Similarly, the annual recovery rates of community height, cover, and aboveground biomass in the heavily degraded desert steppe were the highest among the three degraded steppes after grazing exclusion. These results indicate that grazing exclusion is more effective for vegetation restoration in the heavily degraded desert steppe. The soil total carbon, total nitrogen, total phosphorus, available nitrogen, and available phosphorus concentrations in the moderately and heavily degraded desert steppes were significantly decreased after six years of grazing exclusion, whereas these were no changes in the lightly degraded desert steppe. Structural equation model analysis showed that the grassland degradation level mainly altered the community aboveground biomass and aboveground nutrient pool, driving the decrease in soil nutrient concentrations and accelerating nutrient transfer from soil to plant community, especially in the heavily degraded grassland. Conclusions: Our study emphasizes the importance of grassland degradation level in ecosystem restoration and provides theoretical guidance for scientific formulation of containment policies. [ABSTRACT FROM AUTHOR]

Accelerometers worn by animals produce distinct behavioral signatures, which can be classified accurately using machine learning methods such as random forest decision trees. The objective of this study was to identify accelerometer signal separation among parsimonious behaviors. We achieved this objective by (1) describing functional differences in accelerometer signals among discrete behaviors, (2) identifying the optimal window size for signal pre-processing, and (3) demonstrating the number of observations required to achieve the desired level of model accuracy,. Crossbred steers (Bos taurus indicus; n = 10) were fitted with GPS collars containing a video camera and tri-axial accelerometers (read-rate = 40 Hz). Distinct behaviors from accelerometer signals, particularly for grazing, were apparent because of the head-down posture. Increasing the smoothing window size to 10 s improved classification accuracy (p < 0.05), but reducing the number of observations below 50% resulted in a decrease in accuracy for all behaviors (p < 0.05). In-pasture observation increased accuracy and precision (0.05 and 0.08 percent, respectively) compared with animal-borne collar video observations. [ABSTRACT FROM AUTHOR]

The grassland area is nearly 400 million hm 2 in China, accounting for more than 40% of the land area. Grassland plays an important role in animal husbandry and environmental protection. Although China has taken many measures to curb grassland degradation, grassland degradation is still widely spreading due to overgrazing, abuse of arable land, climate change and other factors. In this paper, the present situation of grassland degradation in China was analyzed in detail. At the same time, the grassland degradation mechanism, the grassland ecosystem function, the grassland degradation diagnosis methods, the grassland restoration and improvement, the utilization of geospatial technology and the grassland management methods were discussed in depth. What’s more, the roots of grassland degradation, the characteristics of grassland degradation, and the control strategies of grassland degradation were analyzed deeply based on the basic situation of grassland degradation in China. The research results not only provide theoretical support for the restoration of grassland ecosystem, but also guide the improvement and restoration of degraded grassland and promote the sustainable development of the grassland ecological animal husbandry in China. [ABSTRACT FROM AUTHOR]

Phenological shifts due to changing climate are often highly species and context specific. Land‐use practices such as mowing or grazing directly affect the phenology of grassland species, but it is unclear if plants are similarly affected by climate change in differently managed grassland systems such as meadows and pastures. Functional traits have a high potential to explain phenological shifts and might help to understand species‐specific and land‐use‐specific phenological responses to changes in climate. In the large‐scale field experiment Global Change Experimental Facility (GCEF), we monitored the first flowering day, last flowering day, flowering duration, and day of peak flowering, of 17 herbaceous grassland species under ambient and future climate conditions, comparing meadows and pastures. Both climate and land use impacted the flowering phenology of plant species in species‐specific ways. We did not find evidence for interacting effects of climate and land‐use type on plant phenology. However, the data indicate that microclimatic and microsite conditions on meadows and pastures were differently affected by future climate, making differential effects on meadows and pastures likely. Functional traits, including the phenological niche and grassland utilization indicator values, explained species‐specific phenological climate responses. Late flowering species and species with a low mowing tolerance advanced their flowering more strongly under future climate. Long flowering species and species following an acquisitive strategy (high specific leaf area, high mowing tolerance, and high forage value) advanced their flowering end more strongly and thus more strongly shortened their flowering under future climate. We associated these trait–response relationships primarily with a phenological drought escape during summer. Our results provide novel insights on how climate and land use impact the flowering phenology of grassland species and we highlight the role of functional traits in mediating phenological responses to climate. [ABSTRACT FROM AUTHOR]

Jamoytius kerwoodi was a primitive, eel‐like jawless fish that lived in the Early Silurian period (444–433 myr) and lived over a stagnant bottom environment, at the transition from a marine‐influenced, probably brackish‐water, deep‐water basin to a shallower water, less saline and probably freshwater basin. Jamoytius lacked teeth and was most likely a free‐living herbivore grazing on floating plants, as were possibly many of its euphanaropid relatives. The palaeoenvironment in which it lived compares well with that of living lampreys, especially as their ectoparasitic mode of life may have evolved from ancestral grazers. [ABSTRACT FROM AUTHOR]

Background: No tick‐borne pathogens (TBPs) causing haemolytic anaemia in cattle have been reported, except Theileria orientalis and complete blood count (CBC) profile is the only haematological parameter to determine the severity of regenerative haemolytic anaemia. Objectives: To identify the causative agents of TBP‐induced haemolytic anaemia and determine haematological parameters that indicate haemolytic anaemia in grazing cattle. Methods: Eighty‐two Korean indigenous cattle (Hanwoo) were divided into two groups: grazing (n = 67) and indoor (n = 15) groups. CBC and serum biochemistry were performed. PCR was conducted using whole blood‐extracted DNA to investigate the prevalence of TBPs. Results: TBP‐induced haemolytic anaemia was observed in the grazing group. In grazing cattle, co‐infection (43.3%, 29/67) was most frequently detected, followed by T. orientalis (37.6%, 25/67) and Anaplasma phagocytophilum infections (1.5%, 1/67). In indoor cattle, only co‐infection (20%, 3/15) was identified. Grazing cattle exhibited regenerative haemolytic anaemia with marked monocytosis, mild neutropenia, and thrombocytopenia. According to grazing frequency, the 1st‐time grazing group had more severe anaemia than the 2nd‐time grazing group. Elevations in indirect bilirubin and L‐lactate due to haemolytic anaemia were identified, and correlations with the respective markers were determined in co‐infected grazing cattle. Conclusions: Quantitative evaluation of haematocrit, mean corpuscular volume, and reticulocytes (markers of regenerative haemolytic anaemia in cattle) was performed for the first time. Our results show that, in addition to T. orientalis, A. phagocytophilum is strongly associated with anaemia. The correlation between haemolytic anaemia severity and haematological parameters (indirect bilirubin, reticulocytes, and L‐lactate) was confirmed. [ABSTRACT FROM AUTHOR]

Simple Summary: The development of the sheep industry plays an important role in increasing the income of farmers and herdsmen and promoting rural revitalization. Genetic improvement is the key to improving the competitiveness of the sheep industry. Tianhua mutton sheep, as China's first mutton fine wool sheep adapted to alpine pastures, have a key advantage over Gansu alpine fine wool sheep in terms of adaptive ability. In order to show the differences in rumen development and microbial structure between Tianhua mutton sheep and Gansu alpine fine wool sheep, the present study was conducted to comprehensively investigate the rumen of the two types of fine wool sheep by Hematoxylin Eosin (H&E) staining, volatile fatty acids (VFAs) assay, and full-length sequencing of 16S rRNA. The results showed that Tianhua mutton sheep had a better performance in the rumen volatile fatty acid content, rumen tissue development, and rumen microorganisms compared with Gansu alpine fine wool sheep, and this study provided a good theoretical explanation for the better adaptation of Tianhua mutton sheep to alpine pastures compared with Gansu alpine fine wool sheep. The purpose of this experiment was to investigate the differences in rumen tissue morphology, volatile fatty acid content, and rumen microflora between Tianhua mutton sheep and Gansu alpine fine wool sheep under the same grazing conditions. Twelve 30-day-old lambs were randomly selected from two different flocks in Duolong Village and grazed together for a period of 150 days. The rumen tissue was fixed with 4% paraformaldehyde and brought back to the laboratory for H&E staining, the volatile fatty acid content of the rumen contents was detected by gas chromatography, and the rumen flora structure was sequenced by full-length sequencing of the bacterial 16S rRNA gene using the PacBio sequencing platform. The acetic acid and total acid contents of the rumen contents of Tianhua mutton sheep were significantly higher than those of Gansu alpine fine wool sheep (p < 0.05). The rumen papillae height of Tianhua mutton sheep was significantly higher than that of Gansu alpine fine wool sheep (p < 0.05). The diversity and richness of the rumen flora of Tianhua mutton sheep were higher than those of Gansu alpine fine wool sheep, and Beta analysis showed that the microflora structure of the two fine wool sheep was significantly different. At the phylum level, Firmicutes and Bacteroidetes dominated the rumen flora of Tianhua mutton sheep and Gansu alpine fine wool sheep. At the genus level, the dominant strains were Christensenellaceae_R_7_group and Rikenellaceae_RC9_gut_group. LEfSe analysis showed that Prevotella was a highly abundant differential species in Tianhua mutton sheep and lachnospiraccac was a highly abundant differential species in Gansu alpine fine wool sheep. Finally, both the KEGG and COG databases showed that the enrichment of biometabolic pathways, such as replication and repair and translation, were significantly higher in Tianhua mutton sheep than in Gansu alpine fine wool sheep (p < 0.05). In general, there were some similarities between Tianhua mutton sheep and Gansu alpine fine wool sheep in the rumen tissue morphology, rumen fermentation ability, and rumen flora structure. However, Tianhua mutton sheep had a better performance in the rumen acetic acid content, rumen papillae height, and beneficial bacteria content. These differences may be one of the reasons why Tianhua mutton sheep are more suitable for growing in alpine pastoral areas than Gansu alpine fine wool sheep. [ABSTRACT FROM AUTHOR]

Context: Grazing of cereal forage crops is perceived as a risk for increased perinatal lamb mortality. Aims: This study evaluated whether grazing oat forage during late pregnancy and/or the lambing period increased lamb mortality compared with grazing a legume (lucerne)-based pasture. Methods: Merino ewes (n = 636) were allocated to two replicates of two litter sizes (singles or twins), which grazed the following three forage treatments: either legume-based pasture or oat forage (Avena sativa) from 42 days before and throughout a 4-week lambing period, or a legume-based pasture until 9–12 days pre-lambing before grazing oats throughout the lambing period. All groups were offered a calcium, magnesium and sodium mineral supplement to reduce the risk of deficiency. Key results: Lamb survival to marking was similar for ewes grazing legumes (84.2 ± 1.94%) or oat forage (78.5 ± 1.94%) throughout, but was reduced (P = 0.022) for ewes that grazed oats only during the lambing period (71.0 ± 1.94%) compared with those that remained on legumes. The latter was associated with a greater (P = 0.016) loss of condition score in the ewes. The weight of lambs at marking age was 2 kg higher (P ≤ 0.05) when grazed on legume-based pasture during the 4 week lambing period rather than oats. Minimal ewe mortality (0.47%) occurred, no metabolic disease was observed and few ewes (1.3%) required assistance at parturition. None of the sampled ewes was subclinically deficient in calcium or magnesium. Conclusions: The study indicates lamb survival was not reduced by grazing oats for an extended period throughout late pregnancy and lambing. Further research is required to determine whether the recorded reduction in lamb survival from grazing oats only during lambing occurs consistently. Implications: Ewes may safely graze oat forage throughout late pregnancy and lambing when offered a calcium, magnesium and salt supplement, without this increasing perinatal lamb mortality relative to a legume-based pasture, but there may be a penalty in lamb growth rates and loss of ewe condition, and lamb survival may be reduced with an abrupt change to oats for the lambing period. Grazing of cereal forage by late-pregnant and lambing ewes is perceived as a risk to perinatal lamb survival. This study investigated whether the duration of grazing ewes on oat forage would reduce lamb survival, and found that grazing oats continuously through late pregnancy and lambing gave similar survival as did grazing legume pasture, whereas grazing oats only during lambing reduced survival. Producers may safely graze oats with late pregnant ewes when supplemented with calcium, magnesium and salt. [ABSTRACT FROM AUTHOR]

Context: In most pasture-based herds in Australia, supplementation with concentrates is normally a flat rate, with quantities determined by average cow requirements, rather than individual-cow requirements. Comparisons between flat rate and individual feeding rarely show advantages such as milk yield benefits for either. However, in pasture-based systems little is understood regarding milk production responses or levels of pasture substitution, when different groups of cows within the herd are fed concentrates at higher supplementation levels. Aims: To investigate the effect on milk yield, feeding time, and ruminating time, of two flat-rate supplementation levels of concentrate, fed over 8 months to 180 cows selected for one of three different parameters. Methods: Cohorts of cows were selected on contrasting differences for either milk production at the start of lactation, bodyweight, or genotype. Each cohort was divided into two balanced groups receiving either 2 or 6 kg DM/cow.day of concentrate, from approximately 12 days in milk onward. All cows remained part of the main milking herd (total herd size 320 spring-calving cows), with a similar opportunity for all cows to graze pasture or feed on supplemented grass silage during periods of pasture shortage. Milk yield was recorded at each milking and feeding behaviour continuously recorded by MooMonitor+ collars. Results were analysed for three seasonal periods of 10, 12 and 10 weeks (P1, P2 and P3 respectively) commencing in spring. Key results: Mean marginal milk response (L milk per 1 kg DM extra of concentrate) over the trial period was 0.88 L, increasing from 0.71 L in P1, to 0.92 L in P2 and 1.03 L in P3. The high-concentrate cohorts recorded reduced feeding time per day of 37 min overall (46, 35 and 29 min for P1, P2 and P3 respectively). Significant differences were found for milk yield and feeding time between several contrasting cohorts. The lowest marginal milk response was for cross-breed cows in P1 with 0.18 L and feeding reduced by 65 min/cow.day, with the contrasting cohort of Friesian cows at a larger marginal response of 0.94 L and smaller feeding time reduction of 32 min/cow.day. Conclusions: The differences among cohorts demonstrated potential for targeted concentrate feeding to specific groups of cows that respond differently in marginal milk yield and grazing behaviour. Implications: When a significant change is made in strategic amounts of concentrate feeding, the impact not only on marginal milk response should be considered, but also on pasture intake. In pasture-based dairy systems little is understood regarding production responses or pasture substitution with different amounts of concentrates fed. Cohorts of cows were selected on contrasting differences for three parameters and fed concentrate at two flat-rate levels, while milk yield and feeding time were monitored. Contrasting responses were found between cross-breed and Friesian cows. Differences between cohorts demonstrated potential for targeted concentrate feeding to contrasting cohorts of cows, and the need to consider both marginal milk response and pasture intake. This article belongs to the Collection ADSS 2022: A Changing Climate for Dairy Science. [ABSTRACT FROM AUTHOR]

Trophic rewilding is gaining rapid momentum as a means of restoration across the world. Advances in research are elucidating the wide‐ranging effects of trophic rewilding and megafauna re‐establishment on ecosystem properties and processes including resilience, nutrient cycling, carbon sequestration, productivity and plant richness.A substantial gap remains in trophic rewilding research on how rewilding affects the frequency and expression of plant functional traits, a key hypothesised avenue by which megafauna can affect biodiversity and ecosystem processes. Yet, there is extensive literature examining the effects of mammal herbivory and exclusion on plant traits from which we may infer potential effects of megafauna reintroductions.Here, we synthesise the literature to show the multifaceted ways that plant functional composition responds to mammalian herbivory and explore how these responses are modulated by the density and identity of herbivores as well as resource availability, ecosystem productivity and historical contingency. We further explore these interactions in a quantitative analysis on European plant species. In addition, we link these broad patterns between mammal herbivory and traits to literature on plant invasions to predict how trophic rewilding may be able to reduce invasive plant dominance, as ecosystems around the world are transitioning towards novel states, occupied by a mix of native and introduced species.Expanding current research on herbivore effects (and their implications for trophic rewilding) beyond plant species richness and towards measurable functional traits can help assess and quantify processes that were not previously possible. Trait approaches can help to test mechanistic hypotheses on the top‐down impacts of large herbivores on plant communities to reveal links between trophic rewilding and ecosystem processes and properties.Synthesis. Given the rapid, much‐needed expansion of restoration and rewilding activities across the world, trait‐based ecology offers a pathway to generalisable predictions of the ecosystem impacts of rewilding, particularly in the context of both the unique landscape processes associated with rewilding (e.g. landscape scale spatiotemporal variability, dispersal) and of widely emerging novel ecosystems. [ABSTRACT FROM AUTHOR]

The term pyric herbivory was first introduced in 2009, describing how fire shapes herbivory as burned areas attract herbivores and, simultaneously, herbivory shapes fuel load and fire behaviour. Pyric herbivory results in a mosaic of patches with varying levels of herbivory and grazing intensity fire intensity and frequency. The importance of pyric herbivory for ecosystem heterogeneity and biodiversity has been described for North American, Australian and African systems, but the concept remains largely untested in a European context.We introduced fire and herbivory in a full‐factorial experiment in a temperate European wood‐pasture system to test whether pyric herbivory operates in ways comparable to grassy systems elsewhere in the world. Using camera traps, we observed the behaviour of cattle in burned subplots (49 m2) compared with unburned subplots. We measured grass height and the proportion of the subplot that burned as variables affecting cattle preference and to assess how grazing affects fire behaviour. We also examined the effect on plant species and life‐form composition after six seasons of treatment.Cattle spent more time grazing in burned than in unburned subplots in the most productive paddock, where a larger proportion of the subplot burned. The proportion of a subplot that burned was positively related to pre‐fire grass height. Moreover, both grass height and the proportion of subplot burned declined in the burned subplots during the 6‐year study period and fire and cattle grazing altered the relative cover of graminoids and shrubs (Rubus spp.), with more graminoids in grazed and/or burned subplots and more shrubs in ungrazed subplots at the end of the study.Synthesis and applications. In our temperate European wood pasture, fire and (cattle) grazing interacted in ways comparable to pyric herbivory in grassy ecosystems elsewhere in the world, especially in the most productive paddock. Fire attracted grazing, with cattle grazing longer on subplots that burned more fully. Grazing also affected fire, where over the course of our experiment cattle grazing reduced grass height and the proportion of a subplot that burned. We suggest that pyric herbivory is an interesting management method to further explore in the European context to address the loss of biodiversity in open ecosystems, particularly in more productive sites. [ABSTRACT FROM AUTHOR]

Pathogens are ubiquitous in ecosystems and play a key role in affecting host community structure. In grasslands, large grazing animals such as cattle and sheep have been shown to affect foliar fungal pathogens. However, theory and empirical studies have come to conflicting conclusions because grazers can directly and indirectly impact pathogens through a wide variety of mechanisms and various grazers may impact pathogens in different ways. A better understanding of the mechanisms by which grazers impact pathogens is important for a fundamental understanding of herbivore pathogen interactions and also to optimise grazing managements to reduce pathogen outbreaks.Here, we investigate multiple mechanisms by which livestock grazing impacts foliar fungal pathogens in grasslands. We integrate a large‐scale grazing experiment, with a removal experiment manipulating plant density and litter biomass, to identify direct and indirect effects of two herbivores on pathogens with different life histories (biotrophs and necrotrophs), in a temperate grassland in northeast China.We found that grazing by cattle and sheep had contrasting impacts: cattle grazing significantly reduced pathogen load, of both biotrophs and necrotrophs, whereas sheep grazing increased biotrophic pathogen load, but did not affect the necrotrophs. The grazing effects were mostly indirect and mediated by different impacts of the herbivores on plant community structure. Cattle grazing reduced pathogen load because it reduced the abundance of susceptible, fast‐growing plants, and the overall density of plants, while sheep grazing increased pathogen infection because it reduced the abundance of resistant plant species. Plant diversity also reduced pathogen infection but these effects were independent of the herbivores.Our results show that different herbivores can have contrasting impacts on pathogen infection through contrasting impacts on host community competence. This suggests the importance of considering multiple mechanisms simultaneously to evaluate the impact of herbivores on host‐pathogen interactions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Copepods are a major component of metazooplankton and important prey for fish and invertebrates such as crabs, shrimps, and flatworms. Certain bloom-forming dinoflagellates can kill copepods, but there is little research on the interactions between copepods and the bloom-forming dinoflagellates Karenia bicuneiformis and K. selliformis. In this study, the survival and ingestion rates of the calanoid copepod Acartia hongi feeding on K. bicuneiformis and K. selliformis were determined as a function of prey concentration. On day 2, the survival of A. hongi incubated with K. bicuneiformis was 90–100% at all the tested prey concentrations, while that with K. selliformis was 0–20% at ≥ 582 ng C mL−1. Compared to other harmful dinoflagellates from the literature, K. bicuneiformis caused low mortality of Acartia; however, K. selliformis caused almost the highest mortality at similar dinoflagellate concentrations. With increasing mean prey concentration, the ingestion rates of A. hongi feeding on K. bicuneiformis increased on day 1, but those on K. selliformis did not increase. Acartia hongi stopped feeding on K. bicuneiformis at mean prey concentrations of ≥ 341 ng C mL−1 and K. selliformis at all prey concentrations on day 2. At the prey concentration of 1000 ng C mL−1, the ingestion rate of A. hongi feeding on K. bicuneiformis was moderate among the rates of Acartia spp. feeding on harmful dinoflagellates; however, that on K. selliformis was the lowest. These results indicate that K. bicuneiformis and K. selliformis differentially affect the survival and ingestion rates of A. hongi. [ABSTRACT FROM AUTHOR]

Our project aimed to investigate whether low maternal calcium status during late gestation decreased weight, growth and survival of lambs born to twin‐bearing Merino ewes grazing pasture. On day 130 of gestation, approximately a 10 mL blood sample was collected from 108 twin‐bearing Merino ewes. Blood pH and calcium ion concentration were measured in whole blood and serum was analysed for calcium, magnesium, phosphate, beta hydroxy butyrate, non‐esterified fatty acids and cholesterol. Six to 18 h after birth and at 49 days of age, lamb live weight was recorded. Ewe serum calcium level at day 130 of gestation were divided into tertiles (1.58–2.13, 2.14–2.30, and 2.31–2.99 mmol/L) with ewes classified as either Low, Med or High (n = 36 per group). A general linear mixed model was used to analyse the data. Survival to 1, 2, 3 and 7 days of age was lower for lambs born to ewes in the Low calcium group compared with those born in the Med and High calcium groups (P < 0.05). At day 49 of age, lamb survival tended to be lower for lambs in the Low (73.6%) compared with Med (86.8%) and High (85.3%) calcium groups (P < 0.1). There were no differences in lamb body weight (P > 0.05). Calcium levels of ewes in the Low calcium group were, on average, indicative of subclinical hypocalcaemia, with this group of ewes also having the lowest lamb survival rate, suggesting that maternal subclinical hypocalcaemia reduces lamb survival. Further studies, particularly on improving maternal calcium levels, are warranted. [ABSTRACT FROM AUTHOR]

Similar to all dairy systems internationally, pasture-based dairy systems are under increasing pressure to reduce their greenhouse gas (GHG) emissions. Ireland and New Zealand are 2 countries operating predominantly pasture-based dairy production systems where enteric CH 4 contributes 23% and 36% of total national emissions, respectively. Ireland currently has a national commitment to reduce 51% of total GHG emissions by 2030 and 25% from agriculture by 2030, as well as striving to achieve climate neutrality by 2050. New Zealand's national commitment is to reduce 10% of methane emissions by 2030 and between 24% and 47% reduction in methane emissions by 2050. To achieve these reductions, factors that affect enteric methane (CH 4) production in a pasture-based system need to be investigated. The objective of this study was to assess the relationship between enteric CH 4 and other animal traits (feed intake, metabolic liveweight, energy corrected milk yield, milk urea concentration, and body condition score [BCS]) in a grazing dairy system. Enteric CH 4 emissions were measured on 45 late lactation (213.8 ± 29 d after calving) grazing Holstein-Friesian and Holstein-Friesian × Jersey crossbred cows (lactation number 3.01 ± 1.65, 538.64 ± 59.37 kg live weight, and 3.14 ± 0.26 BCS) using GreenFeed monitoring equipment for 10 wk. There was a training period for the cows to use the GreenFeed of 3 wk before the 10-wk study period. The average enteric CH 4 produced in the study was 352 g ± 45.7 g per day with an animal to animal coefficient of variation of 13%. Dry matter intake averaged 16.6 kg ± 2.23 kg per day, while milk solids (fat plus protein) averaged 1.62 kg ± 0.29 kg per day. A multiple linear regression model indicated that each one unit increase in energy corrected milk yield, metabolic liveweight and milk urea concentration, resulted in an increase in enteric CH 4 production per day by 3.9, 1.74, and 1.38 g, respectively. Although each one unit increase in BCS resulted in a decrease in 39.03 g CH 4 produced per day. When combined, these factors explained 47% of the variation in CH 4 production, indicating that there is a large proportion of variation not included in the model. The repeatability of the CH 4 measurements was 0.66 indicating that cows are relatively consistently exhibiting the same level of CH 4 throughout the study. Therefore, enteric CH 4 production is suitable for phenotyping. [ABSTRACT FROM AUTHOR]

This article explores the upper boundary of tree cover in drylands, specifically in arid and humid savannas. The researchers use data from the BIODESERT survey to test predictions made by Holdo & Nippert. The results show that the upper boundary on tree cover increases with mean annual precipitation up to a certain threshold, and then declines beyond that threshold. The study supports the mechanisms proposed by Holdo & Nippert, but also identifies some differences in the observed patterns. The findings suggest that factors such as competition for water, light limitation, and grazing can influence tree cover in savannas, and that future global change scenarios may further modify these mechanisms. [Extracted from the article]

The objective was to evaluate the animal production and ingestive behavior of the steers fed different supplements during the growth phase in Aruana grass, and the influence of this supplementation on production performance in feedlot phase. The treatments consisted of three supplements during the growing phase: mineral salt (0.12 g/kg of body weight - BW), low intake energy-protein supplement (1.26 g/kg of BW), and medium intake (3.76 g/kg of BW). Forage canopy characteristics, animal production, and animal behavior on pasture were evaluated in a completely randomized design with three replicates (paddocks). The titanium dioxide marker was used to determine the intake and apparent digestibility during the pasture phase. The production performance in feedlot was evaluated in a completely randomized design with eight replicates (animals). Twenty-four Aberdeen Angus steers (15 ± 1.5 months old; 364.8 ± 21.7 kg BW) were used. At the end of the growth phase the animals were confined and fed a single diet. Dry matter, crude protein, and neutral detergent fiber (NDF) contents of forage and intake were not influenced by the treatments. The average daily gain was higher for the medium intake supplement in pasture phase. The apparent digestibility of NDF (P = and chewing rate were higher for the medium intake supplement. The average daily gain and fat thickness of carcasses were higher for the medium intake supplement in the feedlot phase. The supplements of medium intake increase animal productivity during the growing phase on pastures and cattle's finishing performance in intensive production systems. [ABSTRACT FROM AUTHOR]

Grazing dynamics are one of the most poorly constrained components of the marine carbon cycle. We use inverse modeling to infer the distribution of community‐integrated zooplankton grazing dynamics based on the ability of different grazing formulations to recreate the satellite‐observed seasonal cycle in phytoplankton biomass after controlling for physical and bottom‐up controls. We find large spatial variability in the optimal community‐integrated half saturation concentration for grazing (K1/2), with lower (higher) values required in more oligotrophic (eutrophic) biomes. This leads to a strong sigmoidal relationship between observed mean‐annual phytoplankton biomass and the optimally inferred grazing parameterization. This relationship can be used to help constrain, validate and/or parameterize next‐generation biogeochemical models. Plain Language Summary: To improve predictions of the ocean's ability to feed a growing human population and buffer a changing climate, we need to improve our understanding of what happens to carbon once it is absorbed into the surface ocean. One of the largest knowledge gaps in marine carbon cycling is the role of zooplankton grazing. The rate at which zooplankton graze phytoplankton modifies the size and seasonal evolution of phytoplankton populations and in turn, the associated rates of net primary production at the base of the food‐web, secondary production of grazers (an indicator of fisheries potential) and export production (the biological sequestration of carbon). However, regional differences in grazing, which are difficult to measure outside of the laboratory, remain poorly constrained by observations and thus difficult to model. Here, we run a suite of model simulations, which each simulate grazing differently, then compare the results to infer which grazing dynamics best match observations. We find that there is dramatic spatial variability in how zooplankton, as a community, appear to be grazing and that this variability maps well onto observed phytoplankton abundance, suggesting that the type of zooplankton present may be determined by the amount of prey available. Key Points: Oligotrophic (eutrophic) biomes exhibit more (less) efficient community‐integrated grazing, characteristic of micro‐ (meso‐) zooplanktonWe find a strong link between observed mean‐annual phytoplankton biomass and the grazing dynamics required to recreate its seasonal cycleA type III functional response typically does a better job recreating observed phytoplankton seasonal cycles than a type II response [ABSTRACT FROM AUTHOR]

This study presents a detailed numerical analysis of nonlinear aeroelastic behavior in a two degree of freedom (DOF) model, focusing on plunge and pitch motions and employing the continuation method (CM) with an adaptive step size control algorithm. The research incorporates free-play nonlinearity at the plunge hinge, a common structural nonlinearity in aeronautics that can induce detrimental limit cycle oscillations (LCOs) during flight. By examining three scenarios—linear response, unhindered plunge motion, and nonlinear stiffness behavior—the study assesses the effects of free play on flutter and LCO phenomena, including discontinuity-induced bifurcations like grazing bifurcation. Additionally, the study explores parameter variation for nonlinear flutter analysis, revealing the dynamics of grazing bifurcation and its impact on LCO behavior. The research also demonstrates the method's superior accuracy in flutter speed estimation and mode-switching identification, despite higher computational demands. The findings underscore the diminishing influence of nonlinear free-play behavior on LCO amplitude, providing insights with significant implications for aeroelastic design and aircraft safety. [ABSTRACT FROM AUTHOR]

Grassland is the basis for the development of grassland animal husbandry in China and an important part of the ecosystem. Grazing is the main way of grassland utilization, the most important factor of human interference with grassland, and has an important impact on grassland ecosystem service function. Through the related literature on the effect of grazing on grassland plants, we analyze the effect of grazing on plant communities and their diversity, organizational power, biomass, root system, etc., in order to provide some reference for studying the rational use of grassland and the management of degraded grassland. Currently, unreasonable grazing has caused the degradation of grassland and restricted the development of grassland economy. The next step should be to increase the research on zoned rotational grazing, seasonal grazing and reasonable livestock carrying capacity in combination with grassland management techniques such as fertilization, replanting and pine harrowing. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated the impact of terminal sire (Dorset) use and supplementation with agro-byproducts, specifically corn gluten feed and soy hull, on the carcasses and meat quality of landrace hair sheep (Barbados Blackbelly and St. Croix) under rotational grazing. The crossbred lambs had greater carcass weights and more substantial wholesale cuts from the shoulder, rack, loin, and leg than their purebred counterparts. The purebred supplemented lambs showed comparable enhancements in their carcass characteristics to those of the crossbred lambs. Fresh lamb from the purebred animals displayed a more vivid red and yellow hue compared to the crossbred lambs. The meat from the purebred lambs was found to be softer than that from their crossbred counterparts. Supplementation played a more crucial role than crossbreeding in enhancing carcass quality under the conditions of these experiments. The protein content was notably higher in the meat from the crossbred lambs, while the supplemented lambs produced meat with an increased fat content. Pasture-only lambs had elevated levels of omega-3 and omega-6 fatty acids, displaying a healthier fatty acid profile than those receiving supplementary agro-byproducts. However, they benefited from the improved lipid oxidation stability and texture properties of the meat. The supplement type had no effects on the carcass characteristics, but it affected the meat composition. The effects of breed type (purebred or crossbred) and supplementation of agro-byproducts on the growth, carcass characteristics, and meat quality of landrace hair (Barbados Blackbelly; BB and St. Croix; SX) lambs was evaluated. Thirty-six 7.5-month-old purebred hair (BB and SX; body weight = 24.1 ± 4.26 kg) and terminal sire (Dorset; DO) crossbred lambs (DO × BB and DO × SX; body weight = 31.4 ± 3.50 kg) rotationally grazed predominantly on Jesup tall fescue pasture during spring with or without agro-byproduct supplementation (soyhull or corn gluten feed at 2% of BW). Following a 77d grazing period, the lambs were harvested, and their carcass characteristics and meat composition were evaluated. Both supplementation and crossbreeding significantly increased their carcass weight and primal cuts, whereas only supplementation increased (p < 0.01) the dressing percentage, and crossbreeding increased the shear force (p < 0.01). Regardless of breed type, supplementing agro-byproducts improved the lipid oxidation stability and texture properties of the fresh lamb, whereas the pasture-only lambs had healthier fatty acid profiles compared with the supplemented lambs. The results indicate that both terminal sire crossbreeding and byproduct supplementation can be used to affect the carcass characteristics and meat composition of landrace hair sheep lambs. [ABSTRACT FROM AUTHOR]

Simple Summary: The strategic supplementation of cattle in an intensive production system seeks to maximize intake and improve tropical forage digestibility, improving production performance per area. In this sense, the use of coproducts, such as distillers grains, becomes an economical alternative due to their lower cost in relation to other traditionally used ingredients. The aim of this study was to evaluate the effects of including high-protein distillers dried grains (HP-DDG; 430 g/CP) in supplements for beef cattle in an intensive grazing finishing system. Five uncastrated male Nellore cattle with an average body w (BW) of 413.5 ± 32 kg were used in a 5 × 5 Latin square design. High-protein distillers' dried grain (HP-DDG) does not affect the total voluntary intake of beef cattle when replacing soybean meal (SBM). Pasture dry matter intake does not change. Urinary nitrogen excretion decreased with the inclusion of HP-DDG. HP-DDG decreases the proportion of nitrogen compounds that are recycled to the rumen. The objective was to evaluate the effects of including high-protein distillers dried grains (HP-DDG; 430 g/CP) in supplements for beef cattle in an intensive finishing pasture system. Five Nellore bulls with an average body weight (BW) of 413.5 ± 32 kg were distributed in a 5 × 5 Latin square design. The animals were randomly allocated to Marandu palisade grass paddocks (Urochloa brizantha cv. Marandu), with 0.32 ha each. Protein-energy supplements were evaluated and formulated with different replacement levels (0, 250, 500, 750 and 1000 g/kg) of soybean meal (SBM) by HP-DDG. Supplements were offered once a day in the amount of 6.0 kg/animal. Replacing SBM with HP-DDG had no effect (p > 0.10) on the intake of total and pasture DM, OM, CP, NDFap, digestible organic matter (DOM), metabolizable protein and CP:DOM ratio. Total and pasture DM intake averaged 6.07 and 11.54 kg/day, respectively. Replacing SBM with HP-DDG reduces and increases, respectively, the intake of degradable (RDP) and undegradable (RUP) protein in the rumen (p < 0.10) with a consequent linear reduction in ruminal ammonia concentration (RAN), nitrogen excretion in urine and serum N concentration (SUN) (p < 0.10). In supplements offered in the amount of 6.0 kg animal/day, SBM can be completely replaced by HP-DDG. [ABSTRACT FROM AUTHOR]

Livestock grazing and the collection of bamboo shoots are the main threats to giant panda (Ailuropoda melanoleuca) habitat in the Liangshan Mountains in China. It is important to clarify the effect of these disturbances to the giant panda to formulate targeted management policies. Based on species distribution models and daily activity models, we investigated the effects of livestock grazing and bamboo shoot collection on giant pandas from May 2021 to July 2022. Our results indicated the giant panda's suitable habitat in the reserve covered 51.83 km² (15.02% of the reserve area). Grazing and bamboo shoot collection led to losses of 19.08 km² and 7.68 km² of suitable habitat, respectively. Together, the 2 activities resulted in a loss of 28.35 km² of suitable habitat, which was more than half of the area of panda habitat. The areas of suitable habitat for giant pandas significantly overlapped with the areas affected by both disturbances. Giant pandas did not show significant differences in daily activity rhythms under a single disturbance, but the daily activity rhythms of giant pandas differed when we compared the area combining the 2 disturbances with the undisturbed area. Our study reveals that the anthropogenic disturbances in the reserve have varying effects on the suitable habitat range and daily activity rhythm of giant pandas and evidence of a synergistic effect. Therefore, when formulating relevant conservation policies, it is important to fully evaluate the extent and characteristics of anthropogenic disturbances in shaping the population distribution and habitat preferences of the giant panda and other wildlife to enhance the efficacy of conservation management practices. [ABSTRACT FROM AUTHOR]

Ungulate grazing involves multiple components, including defoliation, dung and urine return, and trampling, which supply offsetting or synergistic effects on plant community composition and productivity (ANPP), but these effects have not been fully studied. Plant functional traits may reflect the response of plants to disturbance and their impact on ecosystem functions. Species turnover and intraspecific trait variation (ITV) are important drivers of community trait composition. We conducted a simulated grazing experiment in a steppe grassland in northern China to examine the effects of defoliation, dung and urine return, and trampling on community-weighted mean (CWM), functional diversity (FD) and ANPP, and to disentangle the roles of species turnover and ITV in driving these changes. We found that defoliation had a dominant effect on CWMs and FDs of all four traits through species turnover and ITV, respectively, resulting in a convergence of traits towards as more resource-acquisitive strategy. Dung-urine return resulted in more resource-acquisitive community traits mainly through ITV, whereas there were no significant effects on FDs except for leaf C/N. Trampling increased CWM of leaf dry matter content primarily driven by ITV, and had no significant effect on FDs. Furthermore, our simulated grazing positively affected ANPP, primarily due to nutrient additions from dung and urine, and ITV largely explained the variation in ANPP. These findings highlight the multifaceted effects of grazing components on community structure and ANPP, and the significance of ITV in shaping grassland plant communities and productivity. [ABSTRACT FROM AUTHOR]

Changes in climate and grazing intensity influence plant-community compositions and their functional structure. Yet, little is known about their possible interactive effects when climate change mainly has consequences during the growing season and grazing occurs off growing season (dormant season grazing). We examined the contribution of trait plasticity to the immediate responses in the functional structure of plant community due to the interplay between these two temporally disjunct drivers. We conducted a field experiment in the northern Mongolian steppe, where climate was manipulated by open-top chambers (OTCs) for two growing seasons, increasing temperature and decreasing soil moisture (i.e., increased aridity), and grazing was excluded for one dormant season between these two growing seasons. We calculated the community-weighted mean (CWM) and the functional diversity (FD) of six leaf traits. Based on a variance partitioning approach, we evaluated how much of the responses in CWM and FD to OTCs and dormant season grazing occur through plasticity. The interactive effect of OTCs and the dormant season grazing were detected only after considering the role of trait plasticity. Overall, OTCs influenced the responses in CWM more than in FD, but the effects of OTCs were much less pronounced where dormant season grazing occurred. Thus, warming (together with decreased soil moisture) and the elimination of dormant season grazing could interact to impact the functional trait structure of plant communities through trait plasticity. Climate change effects should be considered in the context of altered land use, even if temporally disjunct. [ABSTRACT FROM AUTHOR]

Mountainous grasslands in South America, characterized by their high diversity, provide a wide range of contributions to people, including water regulation, soil erosion prevention, livestock feed provision, and preservation of cultural heritage. Prior research has highlighted the significant role of grazing in shaping the diversity and productivity of grassland ecosystems, especially in highly productive, eutrophic systems. In such environments, grazing has been demonstrated to restore grassland plant diversity by reducing primary productivity. However, it remains unclear whether these findings are applicable to South American mountainous grasslands, where plants are adapted to different environmental conditions. To address this uncertainty, we conducted a meta‐analysis of experiments excluding livestock grazing to assess its impact on plant diversity and productivity across mountainous grasslands in South America. In alignment with studies in temperate grasslands, our findings indicated that herbivore exclusion resulted in increased aboveground biomass but reduced species richness and Shannon diversity. The effects of grazing exclusion became more pronounced with longer durations of exclusion; nevertheless, they remained resilient to various climatic conditions, including mean annual precipitation and mean annual temperature, as well as the evolutionary history of grazing. In contrast to results observed in temperate grasslands, the reduction in species richness due to herbivore exclusion was not associated with increased aboveground biomass. This suggests that the processes governing (sub)tropical grassland plant diversity may differ from those in temperate grasslands. Consequently, further research is necessary to better understand the specific factors influencing plant diversity and productivity in South American montane grasslands and to elucidate the ecological implications of herbivore exclusion in these unique ecosystems. [ABSTRACT FROM AUTHOR]

Grassland birds are globally imperiled. Those of endemic Neotropical savannas may be particularly threatened as knowledge of the ecology of many species is lacking, restricting our ability to take decisive conservation action. During the dry (non-breeding) season of 2010, we studied the population size, distribution, and habitat associations of the Cock-tailed Tyrant (Alectrurus tricolor), Black-masked Finch (Coryphaspiza melanotis), and Wedge-tailed Grass-finch (Emberiziodes herbicola) across a disturbance-mediated savanna–grassland gradient in Beni, Bolivia. We used distance sampling and surveyed structural and resource-specific habitat features at plots where birds were present versus random locations. Occupancy models identified fine-scale habitat associations. Cock-tailed Tyrant (7.1 ind./km2) specialized on open habitats in areas expected to be heavily inundated in the wet season, avoided trees, and selected tall grassy swards. Black-masked Finch (25.1 ind./km2) occurred across the gradient, associating with tall, forb-rich swards, sparse shrubs, and low levels of fruiting and seeding vegetation. Wedge-tailed Grass-finch (27.9 ind./km2) also occurred across the gradient, particularly associated with tall, forb-rich swards, abundant seeding grasses, and sparse shrubs. Our results offer the first quantitative abundance estimates for these species in Beni, provide vital baselines for future monitoring, and improve knowledge of the ecology and conservation management needs of these species. Importantly, our results suggest that populations of these three grassland birds may be best maintained in heterogenous, mosaic landscapes that can be produced by carefully managed burning and grazing. Further research in the breeding season would facilitate making stronger, more specific management recommendations. [ABSTRACT FROM AUTHOR]

Wood pastures have been characteristic farming types in the Pannonian biogeographical region over the centuries. In the present work, we studied wood-pastures of typical geographical locations in the North Hungarian Mountain Range of Hungary characterized by similar environmental conditions but grazed by different livestock. The sample area of Cserépfalu was grazed by Hungarian Grey Cattle, while the Erdőbénye was grazed by Hungarian Racka Sheep. Coenological records of the sites were collected from 2012 to 2021 in the main vegetation period according to the Braun-Blanquet method with the application of 2 × 2 m sampling quadrats, where the coverage estimated by percentage for each present species was also recorded. To evaluate the state of vegetation, 'ecological ordering' distribution, diversity, and grassland management values were used. Between the two areas, the grazing pressure of the two studied livestock produced different results. Based on the diversity values, woody–shrubby–grassland mosaic diversity values were high (Shannon diversity: 2.21–2.87). Cattle grazing resulted in a variable and mosaic-like shrubby area with high cover values. Based on our results, grazing by cattle provides an adequate solution for forming and conserving wood-pasture habitats in the studied areas of Hungary. However, if the purpose is to also form valuable grassland with high grassland management values, partly sheep grazing should be suggested. [ABSTRACT FROM AUTHOR]

Although the general impacts of zooplankton grazing on phytoplankton communities are clear, we know comparatively less about how specific grazing strategies interact with environmental conditions to shape the size structure of phytoplankton communities. Here, we present a new data‐driven, size‐based model that describes changes in the size composition of lake phytoplankton under various environmental constraints. The model includes an ecological trade‐off emerging from observed allometric relationships between (1) phytoplankton cell size and phytoplankton growth and (2) phytoplankton cell size and zooplankton grazing. In our model, phytoplankton growth is nutrient‐dependent and zooplankton grazing varies according to specific grazing strategies, namely, specialists (targeting a narrow range of the size‐feeding spectrum) vs. generalists (targeting a wide range of the size‐feeding spectrum). Our results indicate that grazing strategies shape the size composition of the phytoplankton community in nutrient‐rich conditions, whereas inorganic nutrient concentrations govern phytoplankton biomass. Under oligotrophic regimes, the phytoplankton community is dominated by small cell sizes and the grazers have little to no impact. Under eutrophic regimes, dominating specialist grazers push phytoplankton towards small cells, whereas dominating generalist grazers push phytoplankton towards large cells. Our work highlights that trait‐based modeling, based on realistic eco‐physiological trade‐offs, represents a valuable tool for disentangling the interactive roles played by nutrient regimes and grazing strategies in determining the size compositions of lake phytoplankton. Ultimately, our study offers a quantitative basis for understanding how communities of lake phytoplankton may reorganize in the future in response to changes in nutrient levels and zooplankton grazing strategies. [ABSTRACT FROM AUTHOR]

The Antarctic krill Euphausia superba is often considered an herbivore but is notable for its trophic flexibility, which includes feeding on protistan and metazoan zooplankton. Characterizing krill trophic position (TP) is important for understanding carbon and energy flow from phytoplankton to vertebrate predators and to the deep ocean, especially as plankton composition is sensitive to changing climate. We used repeated field sampling and experiments to study feeding by juvenile krill during three austral summers in waters near Palmer Station, Antarctica. Our approach was to combine seasonal carbon budgets, gut fluorescence measurements, imaging flow cytometry, and compound‐specific isotope analysis of amino acids. Field measurements coupled to experimentally derived grazing functional response curves suggest that phytoplankton grazing alone was insufficient to support the growth and basal metabolism of juvenile krill. Phytoplankton consumption by juvenile krill was limited due to inefficient feeding on nanoplankton (2–20 μm), which constituted the majority of autotrophic prey. Mean krill TP and the metazoan dietary fraction increased in years with higher mesozooplankton biomass, which was not coupled to phytoplankton biomass. Comparing TP estimates using δ15N of different amino acids indicated a substantial and consistent food‐web contribution from heterotrophic protists. Phytoplankton, metazoans, and heterotrophic protists all were important contributors to a diverse krill diet that changed substantially among years. Juvenile krill fed mostly on heterotrophic prey during summer near Palmer Station, and this food web complexity should be considered more broadly throughout the changing Southern Ocean. [ABSTRACT FROM AUTHOR]

Understanding how cool-season C3 and warm-season C4 grasses will respond to climate change is critical for predicting future ecosystem functioning in many grasslands. With warming, C4 grasses are expected to increase relative to C3 grasses, but alterations in the seasonal availability of water may also influence C3/C4 dynamics because of their distinct seasons of growth. To better understand how shifts in the seasonal availability of water can affect ecosystem function in a northern mixed-grass prairie in southeastern Wyoming, we reduced early season rainfall (April–June) using rainout shelters and added the amount of excluded precipitation later in the growing season (July–September), effectively shifting spring rainfall to summer rainfall. As expected, this shift in precipitation seasonality altered patterns of soil water availability, leading to a 29% increase in soil respiration and sustained canopy greenness throughout the growing season. Despite these responses, there were no significant differences in C3 aboveground net primary production (ANPP) between the seasonally shifted treatment and the plots that received ambient precipitation, likely due to the high levels of spring soil moisture present before rainout shelters were deployed that sustained C3 grass growth. However, in plots with high C4 grass cover, C4 ANPP increased significantly in response to increased summer rainfall. Overall, we provide the first experimental evidence that shifts in the seasonality of precipitation, with no change in temperature, will differentially impact C3 versus C4 species, altering the dynamics of carbon cycling in this geographically extensive semi-arid grassland. [ABSTRACT FROM AUTHOR]

Microbial diversity in the fecal samples of Bactrian camels in Transbaikalia under various grazing management (free grazing (group I), mixed (group II), and stall housing (group III)) was revealed using high-throughput sequencing of the 16S rRNA gene variable regions. The microbial community of the fecal microbiota was found to be diverse and to depend on the camel grazing management. The most common phyla of the camel fecal microbiota were Bacillota and Bacteroidota. The phylum Verrucomicrobiota was a codominant in the fecal microbiota of groups I and II of animals, and Actinomycetota, in the feces of camels of group III. Changes in the fecal microbiota structure and taxonomic diversity occurred as camel grazing management and feeding conditions changed. Free grazing resulted in high diversity of the prokaryotic community in the fecal microbiota. In addition, differences in taxonomic composition depending on sex were found, which were in the abundance of taxa rather than in their presence or absence. The results contribute to the current understanding of the fecal microbiota of camels under different management conditions and provide evidence of the influence of nutrition on the fecal microbiota under different management conditions. Our results may be useful for addressing the issues of reproduction and conservation of the Transbaikal camel (Camelus bactrianus). [ABSTRACT FROM AUTHOR]

Mammalian herbivores play a pivotal role in Earth System processes by affecting biogeochemical cycles and ecosystem functioning, potentially leading to significant repercussions on atmosphere–biosphere feedbacks. Global dynamic models of mammalian populations can improve our understanding of their ecological role at large scales and the consequences of their extinctions. However, such models are still lacking and mammals are poorly integrated in Earth System Science.We developed a mechanistic global model of terrestrial herbivore populations simulated with 37 functional groups defined through the analysis of eco‐physiological traits across all extant herbivores (2599 species). We coupled this model with a global vegetation model to predict herbivores' maximum potential biomass in pre‐industrial and at present‐day and to study the environmental drivers explaining the distribution of herbivore biomass. Present‐day biomass was estimated by accounting for anthropogenic activity causing habitat and range losses.We show that natural ecosystems could have sustained a potential wild herbivore wet biomass of 330 Mt (95% CI: 245–417), comprised of 193 Mt (95% CI: 177–208) by large species (body mass >1–10 kg, depending on functional group) and 138 Mt (95% CI: 68–209) by small species. We estimate that the remaining present‐day large herbivores biomass is 82 Mt (95% CI: 32–133), reduced by 57% due to anthropogenic activity; consequently, small herbivores currently dominate global herbivore biomass with 98 Mt (95% CI: 91–106, −29%). Losses vary greatly across climatic zones and functional groups, suggesting that size is not the only discriminant feature of biomass decline.Actual evapotranspiration is the most important driver of total, large and small herbivore biomass and explains 64%, 59% and 49% of its variation, respectively. Distribution of modelled and observed large herbivores' biomass suggested a high dependency on energy and water with more biomass in hot and wet areas. These results challenge the notion that large herbivore biomass peaks primarily in ecosystems with intermediate precipitation levels such as savannas.Outside Africa and the Tropics, pre‐industrial biomass hotspots occur in areas today dominated by humans; this could undermine the recovery of larger species biomass in certain areas. Our herbivore biomass estimates provide a quantitative benchmark for setting conservation and rewilding goals at large spatial scales. The herbivore model and functional classification create new opportunities to integrate mammals into Earth System Science and models. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The study of diet and its relationship with available resources allows us to evaluate how species that differ in their degree of ecological flexibility respond to natural and anthropogenic variations that affect food availability. In the central Monte desert, extensive cattle ranching reduces the abundance of grass seeds, the most consumed and preferred food by the harvester ants Pogonomyrmex inermis Forel, 1914, Pogonomyrmex mendozanus (Cuezzo & Claver, 2009), and Pogonomyrmex propinqua (Johnson, 2021). We studied the diet of these species in grazed and ungrazed habitats over 4 years, including a period during which the abundance of grass seeds naturally decreased. We expected that ants would modify their diet in grazed sites and that the response would be different among species depending on their ecological flexibility. The three species presented a mainly granivorous diet in both grazing conditions and during the 4 years, but showed differences in the breadth of their diet. Pogonomyrmex inermis and Pogonomyrmex propinqua always had a narrow diet that consisted mainly of grass seeds, while Pogonomyrmex mendozanus modified its diet to include higher proportions of shrub seeds and other items when the abundance of grass seed decreased. In a scenario of scarce resources, this flexibility could represent an advantage over a more strict graminivorous diet. [ABSTRACT FROM AUTHOR]

Nardus stricta dominated grassland is a specific habitat occurring on the nutrient-poor soils. Its large areas were formed as a result of livestock grazing. However, landscape management underwent significant changes over the last decades including grazing cessation. This triggered successional processes leading to considerable changes in floristic composition reported from numerous European regions. We focused on this phenomenon in the Western Carpathian high mountains, where the issue was not studied sufficiently. Our research, based on pairwise comparison of 19 historical and recent phytocoenological relevés, confirmed changes here. These include (i) decrease in cover of some diagnostic species of Nardetea strictae class, especially Nardus stricta, (ii) increase in competitively strong species with their high biomass productivity, (iii) shift in floristic composition indicating conversion of Nardion strictae vegetation into other communities, especially those of Loiseleurio-Vaccinietea class, (iv) increase in Shannon-Wiener index values and (v) enrichment of originally oligotrophic grasslands with some nutrient-demanding species, mainly at lower altitudes and decrease in light-demanding species. [ABSTRACT FROM AUTHOR]

Improved nitrogen utilization of dairy production systems should improve not only the economic output of the systems but also the environmental metrics. One strategy to improve efficiency is through breeding programs. Improving a trait through breeding is conditional on the presence of exploitable genetic variability. Using a database of 1,291 deeply phenotyped grazing dairy cows, the genetic variability for 2 definitions of nitrogen utilization was studied: nitrogen use efficiency (i.e., nitrogen output in milk and meat divided by nitrogen available) and nitrogen balance (i.e., nitrogen available less nitrogen output in milk and meat). Variance components for both variables were estimated using animal repeatability linear mixed models. Genetic variability was detected for both nitrogen utilization metrics, even though their heritability estimates were low (<0.10). Validation of genetic evaluations revealed that animals divergent for nitrogen use efficiency or nitrogen balance indeed differed phenotypically, further demonstrating that breeding for improved nitrogen efficiency should result in a shift in the population mean toward better efficiency. Nitrogen use efficiency and nitrogen balance were not genetically correlated with each other (<|0.28|), and neither metric was correlated with milk urea nitrogen (<|0.12|). Nitrogen balance was unfavorably correlated with milk yield, showing the importance of including the nitrogen utilization metrics in a breeding index to improve nitrogen utilization without negatively impacting milk yield. In conclusion, improvement of nitrogen utilization through breeding is possible, even if more nitrogen utilization phenotypic data need to be collected to improve the selection accuracy considering the low heritability estimates. [ABSTRACT FROM AUTHOR]

Grasslands store large amounts of C; however, the underlying mechanisms of soil C sequestration after grazing exclusion are not well known. This study aimed to elucidate the drivers of soil organic C (SOC) sequestration from plant and microbial residues in temperate grasslands after long-term (~ 40 years) grazing exclusion. We conducted in situ 13C-CO2 labelling experiments in the field and traced 13C in plant-soil systems paired with biomarkers to assess the C input from plants into soils. Long-term grazing exclusion increased all plant and soil pools including shoots, roots, microbial biomass and necromass. 13C allocation in these pools also increased, whereas 13C was lost via respiration as CO2 from soils decreased. 13C incorporation into the soil and microbial biomass increased with 13C allocation into the roots. Grazing exclusion for over 40 years increased the total SOC content by 190%, largely due to increases in fungal necromass C, and there was a minor contribution of lignin phenols to SOC accrual (0.8%). Consequently, grazing exclusion boosts not only aboveground biomass, but also larger roots and rhizodeposition, leading to microbial biomass and necromass formation. Microbial necromass and lignin phenols contribute to SOC accrual under grazing exclusion, and microbial necromass, especially fungal necromass, makes a larger contribution than lignin phenols. [ABSTRACT FROM AUTHOR]

In the practical scale of cyanobacterial cultivation, the golden algae Poterioochromonas malhamensis is a well-known predator that causes devastating damage to the culture, referred to as pond crash. The establishment and maintenance of monoculture conditions are ideal for large-scale cultures. However, this is a difficult challenge because microbial contamination is unavoidable in practical-scale culture facilities. In the present study, we unexpectedly observed the pond crash phenomenon during the pilot-scale cultivation of Synechococcus elongatus PCC 7942 using a 100-L photobioreactor. This was due to the contamination with P. malhamensis , which probably originated from residual fouling. Interestingly, we found that S. elongatus PCC 7942 can alter its morphological structure when subjected to continuous grazing pressure from predators, resulting in cells that were more than 100 times longer than those of the wild-type strain. These hyper-elongated S. elongatus PCC 7942 cells had mutations in the genes encoding FtsZ or Ftn2 which are involved in bacterial cell division. Importantly, the elongated phenotype remained stable during cultivation, enabling S. elongatus PCC 7942 to thrive and resist grazing. The cultivation of the elongated S. elongatus PCC 7942 mutant strain in a 100-L pilot-scale photobioreactor under non-sterile conditions resulted in increased cyanobacterial biomass without encountering pond crash. This study demonstrates an efficient strategy for cyanobacterial cell culture in practical-scale bioreactors without the need for extensive decontamination or sterilization of the growth medium and culture facility, which can contribute to economically viable cultivation and bioprocessing of microalgae. [ABSTRACT FROM AUTHOR]

When emersed, intertidal seaweeds experience rapid changes in environmental conditions. On warm sunny days, seaweeds can desiccate soon after emersion. On rainy days or in areas with freshwater inputs, they may experience rapid drops in salinity. To determine whether one low tide's exposure to environmental stress alters seaweed growth, palatability to herbivores, and dimethylsulfoniopropionate (DMSP) concentrations, we exposed Ulva fenestrata to desiccation and hyposaline conditions for 3 h in summer and winter. Two days later, summer desiccation decreased growth, consumption by Lacuna vincta, and DMSP by 71%, 83%, and 67%, relative to controls. Winter desiccation reduced DMSP by 19% and did not affect growth or L. vincta feeding. Summer hyposaline conditions increased growth by 75% but did not affect L. vincta grazing or DMSP, whereas winter hyposaline conditions reduced growth by 37%. After 2 days of exposure to L. vincta, seaweeds were allowed to recover for 7 days, then DMSP was measured. U. fenestrata desiccated in the summer did not survive. Average DMSP concentrations were 127% higher in grazed than ungrazed seaweed in the summer salinity experiment, providing evidence that grazing induces DMSP. No DMSP induction occurred in winter, possibly because grazing rates were much lower. In a follow-up summer desiccation experiment, maximum quantum yields (MQYs) and DMSP decreased to 12% and 14% of controls within an hour. After 7 days, MQY and DMSP concentrations recovered, but growth was 81–97% lower in seaweeds desiccated for 30–60 min, relative to controls. These results provide the first evidence for grazer-induced DMSP increases. [ABSTRACT FROM AUTHOR]

Some species are severely affected by global change, whereas others can survive or even thrive under the same circumstances. Species with more flexible behaviours can better cope with changes in the environment than those with more stereotyped behaviours; therefore, knowing the limits of behavioural flexibility is critical to predict their responses to global change.Livestock grazing is the most widespread land use in deserts and a major driver of vegetation change. In turn, unpredictable and sporadic rainfall can increase the negative impact of grazing. The interaction of both factors is more relevant nowadays as a consequence of climate change.In the central Monte desert, cattle grazing and inter‐annual variations in rainfall reduce the abundance of seeds preferentially consumed by granivorous animals. There we analysed the dietary flexibility of the specialist harvester ant Pheidole spininodis in response to inter‐annual variations in seed availability during four consecutive years at sites with contrasting grazing pressure.Pheidole spininodis expanded its diet by including other items and decreasing seed consumption as seed availability decreased over the years, but this response did not differ between grazing conditions, probably because the drastic reduction in seed abundance at the regional scale blurred the contrast between grazed and ungrazed sites.Our results highlight the potential dietary flexibility of a specialist species that, under adverse conditions, can modify its diet. Future studies should investigate whether these changes in the diet of P. spininodis in contexts of low resource availability may have negative effects on its survival, as previously reported for other granivorous species. [ABSTRACT FROM AUTHOR]