Pasture Grazing Research Articles

Combination of cattle urine and dung patches synergically increased nitrous oxide emissions from a temperate grassland under wet conditions

During grazing, some of the nutrients ingested by cattle are returned to grassland as urine and dung patches and can be lost as greenhouse gases. Sites where cattle congregate are more likely to have overlapping excreta patches favouring enhanced nitrous oxide (N2O) emissions. However, there is no consensus about the magnitude of these or simultaneous methane (CH4) emissions or potential mitigation options. This study investigated the effect of combined cattle dung and urine depositions on N2O and CH4 emissions, compared with emissions from separate depositions, under different weather conditions. Local emission factors (EFs) were then calculated for both gases. A quantitative assessment of published studies was also performed to search for N2O emissions drivers. Two field experiments were performed during two 98-day trials under dry and wet conditions in Tandil, Argentina. Treatments included fresh excreta patches of urine (0.75 L), dung (2.50 kg), dung + urine (2.50 kg + 0.75 L) from Holstein dairy cows, and a control (without excreta). Soil and excreta properties were analysed, and N2O and CH4 fluxes from the patches were measured using the static chamber technique. Patches containing dung were shown to be localised CH4 hotspots. Urine applied to soil, and the addition of urine to dung patches had a negligible effect on CH4 fluxes. Urine, dung and combined patches were found to be localised N2O sources. Adding urine to dung patches under wet weather had a significant synergetic effect (threefold increase) on cumulative N2O emissions compared with the theoretical sum of separate excreta patches. Adding urine to dung patches under dry conditions gave an additive effect on N2O. These findings suggest that preventing overlapping excreta patches under wet conditions can help mitigate N2O emissions from temperate managed grazed pastures. The effect of combining excreta patches was also evident in the EF values obtained. That for CH4 was consistent with the default IPCC value (0.75 g CH4 kg−1 VS), while N2O (EF = 0.03–0.39%) was lower than the updated IPCC 2019 value of 0.6%.

NITROGEN UTILISATION AND GREENHOUSE GAS EMISSIONS IN SMALL-SCALE DAIRY SYSTEMS IN THE HIGHLANDS OF CENTRAL MEXICO

<p><strong>Background:</strong> Nitrogen (N) plays an important role within milk production systems (MPS), as an indicator of environmental and economic efficiency. <strong>Objective. </strong>The objective was to determine utilisation of N offered in the ration and estimate GHG from the enteric fermentation and manure management in 12 small-scale dairy farms under two feeding strategies. <strong>Methodology.</strong> Six farms had their herds in confinement under a cut-and-carry feeding system, and six farms implemented day grazing of mixed pastures, both systems used commercial concentrates as a supplement. Cows in milk production and their replacements were considered in the study. Pasture intake was calculated by difference in dry matter intake, using 3.2 % of live weight as intake factor. The N utilisation was determined by difference between N intake and excretion at each farm during a whole year operation. The GHG emissions were estimated following Tier 2 guidelines rom IPCC. Differences in feeding strategies were analysed with a completely random block design using farms as a blocking factor. <strong>Results.</strong> Mean farm size was 5.0 ha for cut-and-carry and 16.0 ha for grazing, and dry matter feed self-sufficiency was 62 and 83% respectively, considering 12% and 22% refusals for each strategy. There were no statistically significant differences (P>0.05) for any of the N utilisation components (N in diet, N in milk, N in manure, NH<sub>3</sub> and N<sub>2</sub>O or GHG emissions. <strong>Implications.</strong> This is a novel report on assessing N fluxes and GHG emissions from small-scale dairy systems in Mexico and Latin America. <strong>Conclusions.</strong> In general, 87.6% of the N consumed is excreted in manure and urine. The feeding strategies did not diverge enough to have an impact on GHG emissions.</p>

Understanding sheep baa‐haviour: Investigating the relationship between pasture and animal grazing patterns

AbstractBackgroundGrasslands are the primary source of feed for grazing livestock, and as such, knowledge on how to best manage livestock and grasslands, through the use of spatiotemporal modelling, will assist in the long‐term management of a valuable ecosystem resource.MethodsThis study was conducted over 14 months between March and April 2017 in Orange, NSW, Australia. The study evaluated sheep behaviour in relation to the presence of pasture species, environment and paddock structures, using random forest modelling, to predict sheep location under continuous high (HSR, 13 DSE ha−1) and low (LSR, 7 DSE ha−1) stocking rates.ResultsIn the LSR, significant drivers included water, shade and fence lines (p < 0.01). In the HSR, only fence lines and available biomass were found to be significant (p < 0.01). The presence of green legumes in both stocking rates often increased residency by sheep. Animals spent more time together in the LSR, suggesting that social behaviour played a larger role than pasture quantity and quality in driving grazing behaviours.ConclusionsUnderstanding how pasture type can influence grazing behaviours and also how animal behaviour affects pasture performance and utilisation is important in developing long‐term sustainable management strategies on a paddock scale.

Feedlot rearing versus pasture grazing enhances plasma leptin and insulin-like growth factor-1 concentrations but does not anticipate puberty in dairy buffalo (Bubalus bubalis) heifers

Plasma Leptin (LEP) and Insulin-like Growth Factor-1 (IGF-1), related to growth and puberty onset, were assayed in growing buffalo heifers from 8 up to 21 months of age, reared in feedlot (FR, n = 13; initial body weight 132 ± 11 Kg) or grazing at pasture (PG, n = 13; 137 ± 12 Kg). The mean age at puberty was not different between the two groups (599.5 and 610.5 days, in FR and PG, respectively). At puberty, FR heifers showed higher BCS, and higher average daily weight gain (DWG) than PG ones (0.87 vs. 0.62 Kg/day), and were heavier (462 vs. 375 Kg). A negative correlation between DWG and age at puberty was significant for the PG group. Plasma Inhibin-A increased in both groups one month before puberty. Plasma LEP and IGF-1 sharply increased 2 months before puberty (about 18 months old) in FR heifers only, which showed higher concentrations of both hormones than PG heifers. Plasma LEP levels correlated positively with body weight and IGF-1. Despite hormone levels being affected by rearing systems, and being lower in heifers grazing at pasture, these latter experienced adequate growth and reproductive maturation. In fact, grazing heifers reached puberty at the same age as the feedlot reared ones, with shorter puberty–conception interval (51.3 vs. 67.2 days, for PG and FR groups, respectively) and no difference in conception rates (83.3 and 84.6%, for PG and FR groups respectively). The higher BW and DWG of FR heifers were due to body fat deposition, which did not anticipate the puberty onset. Highlights Metabolic hormones Leptin and IGF-1, linked to puberty attainment, are good indicators of the animal energetic state. Buffalo heifers reared in intensive system vs. the ones at pasture had higher hormone levels and growth, but reproductive performance was not better. Post-weaned heifers can be reared at pasture during growth and breeding, without compromising reproductive performance.

Extreme Weather and Grazing Management Influence Soil Carbon and Compaction

Understanding the influence of cattle grazing on soil carbon and bulk density during extreme dry to wet periods can help us design more resilient and sustainable grazing systems for low-input management scenarios. A study was conducted to evaluate changes in loss-on-ignition (LOI) carbon and bulk density (BD) in the top 20 cm soil layer when eight continuous grazing (CG) pastures were converted to either continuous grazing with hay distribution (CHD-4) or strategic grazing (STR-4). STR included lure management of cattle with movable-equipages, exclusion and over-seeding erosion-vulnerable areas, and a relaxed rotational grazing. Changes in relationships between cattle density (CD), LOI, and BD were evaluated for change in grazing management from 2015 to 2018. Reduction in LOI carbon (0–5, 5–10, 10–20 cm) and BD (5–10 cm) were observed in both CHD and STR pastures in 2018. CD in 2015 had either no relationship or a negative relationship on LOI while in 2018, CD positively influenced LOI in CHD (0–5 cm) and STR (0–5 and 5–10 cm) pastures. STR had lower BD with higher CD further away from concentrated flow paths mirroring cattle movement. Exclusions in the STR pastures had the greatest reduction in BD. Even with reduced carbon in the 0–5 cm soil layer the reduction in BD in the 5–10 cm soil layer helped build resilience in grazing systems that experience extreme weather events such as going from very dry to extensively wet.

Effect of Housing on Lameness, Body Condition Score and Udder Health of Sahiwal Dairy Cattle

Background: Lameness is a huge problem in intensive livestock production, leading to enormous losses in terms of stress to animals, less reproductive ability and increased chances of mastitis. Zero grazing system is needed for today’s intensive livestock production, but it has also led to increased lameness chances, unnecessarily increased body condition score and increased mastitis incidences. On the other hand, pasture grazing promotes cows to exhibit natural behaviour, which improves the health and welfare of animals. Methods: Present study was aimed to find effect of housing on lameness, body score and udder health of Sahiwal cows. 204 Sahiwal cows were included in the study out of which 50 were reared on pasture and the rest were stall-fed. Lameness and body condition scoring was done and milk samples were collected using aseptic techniques. Result: Clinical lameness is quite low in Sahiwal i.e. 6% with no significant difference between pasture grazing and stall fed animals. Stall fed animals revealed significantly more claw lesions than pasture grazed animals. Grazing animals revealed significantly lower body condition score than stall fed animals. In term of udder health, stall fed animals revealed higher odds of mastitis than pasture grazed animals.

Effects of season and management on fatty acid profile, ACE-inhibitory activity and anti-oxidant properties of Italian Alpine cheeses

Mountain dairy products are recognised as high-quality food but there are still few studies concerning the effects of seasonality and herd management on the profile of bioactive compounds in cheeses. This study was planned to assess the effect of season (summer versus winter) and feeding management (pasture versus integration) on fatty acids (FAs) profile, anti-hypertensive (ACE-IA) and anti-oxidant properties (ABTS-SA, FRAP), total thiol (SH) and phenolic (TP) contents of cheeses from two dairy cow farms (Farm A and Farm B) located in Piedmontese Alps (Italy). Cheese samples collected in the farms were submitted to an integrated analytical approach and the results were processed by full factorial ANOVA and PCA. The trends observed from the FAs profile confirmed the beneficial influence of supplying fresh forage to lactating cows. The ACE-IA was higher in summer than in winter cheese but depended upon the farm factor. Among the indicators of antioxidant activity, only the ABTS-SA was affected by the season, even though with significant differences between the farms. The TP content did not show any clear pattern, but it was higher than the values described in the literature. The PCA of all the data showed that several FAs and the ABTS-SA gave relevant contributions to clearly group the cheese samples according to the production season or farm. In conclusion, alpine cheese exhibited high nutritional quality under the consumers’ health standpoint, and the identification of the healthier summer cheeses for traceability or labelling purposes, can be obtained. Highlights Seasonality and herd management practices affected the nutritional quality of cheese produced in two dairy farms in Piedemontese Alps. Lipid quality was affected by the feeding strategy, with the greater improvements obtained by pasture grazing or fresh grass consumption in the barn. ACE-inhibitory activity and anti-oxidant properties were influenced by both seasonality and farm of origin, with the best values measured in summer cheese.

Espeletia saboyana (Millerieae, Asteraceae), a New Critically Endangered Caulirosula from Cordillera Oriental, Colombia

Abstract— Espeletia saboyana, a new species from Páramo de Saboyá, Boyacá department, Colombia, is described and illustrated. It is a caulescent rosette up to 5 m tall, with whitish-cinereous appearance, sessile leaves with elliptic laminae, cymose capitulescences with aphyllous unbranched portion and 3‐5 capitula, 5‐13 phyllaries, the external ones 17.4‐26.0 mm long, 49‐92 ray florets 13.0‐18.4 mm long, and 162‐347 disc florets 8.2‐12.2 mm long. Espeletia saboyana is similar to E. incana, but with longer laminae, bigger foliar area, and fewer ray floret series. It is also similar to E. murilloi, but with longer ray tubes, ray paleae, disc corollas, disc styles, disc anther appendages, and disc paleae. In addition, E. saboyana is distributed allopatrically in regard to E. incana and E. murilloi. This species is informally proposed to be listed as IUCN Critically Endangered (CR), since it is restricted to a single population with extent of occurrence = 1.83 km2 and area of occupancy = 0.48 km2. Besides, this population is severely fragmented into 40‐50 demes, the largest one covering only 34,000 m2. Most demes are found in humid soils and wetlands submitted to continuous habitat deterioration as water is drained for use in agriculture. Espeletia saboyana is rare or absent in these newly drained areas, which are either colonized by other species that thrive on drier soils or transformed into pastures for cattle grazing. Furthermore, analyses of size class distributions show that recruitment rates of E. saboyana are significantly lower in small demes, which, if not reversed, can further reduce population size in the near future.

Limitations to the soil impacts of tree regrowth in improved cattle pasture

Tree regrowth plots are often utilised to reduce soil erosion and increase soil organic carbon (SOC) as well as providing shade for cattle. However, unfenced tree regrowth plots have been found to make limited improvements in soil health in grazing lands. To better inform land management decisions, the impact of an unfenced tree regrowth on soil erosion rates and soil properties was analysed for an improved (i.e., sown with introduced species) cattle pasture in Eastern Australia. Soil cores were collected to 20 cm depth for two paired transects: one with improved pasture and a tree plot, and one consisting only of improved pasture. Samples were analysed for soil organic carbon and soil properties and soil erosion rates were determined using the diffusion and migration model (DMM) and Revised Universal Soil Loss Equation (RUSLE). Maximum DMM erosion rates were similar for the two transects at 2.7 (tree plot) and 2.3 (pasture) t.ha−1.yr−1, with the tree plot not having a statistically significant effect. RUSLE erosion rates showed less similarity for the transects at 5.58 (pasture) and 3.08 (tree plot) t.ha−1.yr−1. SOC was lower within the tree plot compared to the rest of the transect, while it was significantly higher in the pasture than the tree plot transect (4.93% compared to 3.72%). To examine if the tree plot is buffering against higher erosion caused by this, the RUSLE cover factor was substituted for that of the pasture transect. However, no such effect was observed. Overall, the tree plot had no significant effect on SOC and erosion in this improved pasture grazing system. This has implications for the design of tree plots and their location, which is significant due to their perceived role in regenerative agriculture practices.

Traditional grazing management creates heterogeneous swards and fosters grasshopper densities

Common pastures were once the dominant type of land use in many European regions. However, during the past 150 years, they have declined dramatically. Recent studies have shown that they are hotspots for rare plant, butterfly, and bird species in the study area, the Bavarian pre-Alps (southern Germany). However, studies on the value of these pastures for Orthoptera (hereinafter termed "grasshoppers") have been scarce. Here, we studied the effects of traditional summer grazing in common pastures on grasshopper assemblages. Our study revealed that grasshopper species richness did not differ between common pastures (n=57) and controls (n=57). By contrast, density of all and of threatened species varied between common pastures and controls in all plots and within the two vegetation types with the highest grasshopper abundance, grasslands on mineral soil and fens. Two threatened species, Pseudochorthippus montanus and Stethophyma grossum, were identified as indicators for common pastures; controls had no indicative species. Traditional low-intensity grazing in common pastures has resulted in open and heterogeneous swards with some bare ground, a low cover of litter and an intermediate vegetation height favouring high densities of grasshopper species in general and threatened species in particular. This is especially true for the two most productive vegetation types, grasslands on mineral soil and fens. To promote biodiversity in general and grasshopper densities in particular, we recommend maintaining traditional cattle grazing (stocking capacities: 0.5-2.0 livestock units/ha) in common pastures. Where possible, this grazing regime should also be introduced in the surrounding landscape.

Legions of Pigs in the Early Medieval West

Over a millennium ago, images began to appear in Christian church settings—as decorations of holy book covers, within the pages of books, and on church walls—of Jesus exorcizing a multitude of demons, named Legion, from a man into a herd of pigs who then rush into the sea and drown. In using this biblical story to frame the narrative of Legions of Pigs in the Early Medieval West, Jamie Kreiner makes clear the ambiguities of the pig as “both unholy and redemptive, both historically situated and universally relevant” (195). The pigs as Legion and a legion of pigs on farm and field are intertwined.Rather than approaching the history of the pig as only an issue of agricultural production, Kreiner examines it as “a history of the counterintuitive connections that developed between the micro-universes of pig husbandry and early medieval institutions and ideas on a wider scale” (4). She uses the pig as an entry point for thinking through how early medieval people thought about their environment. Her approach is to place the pig within wider social, cultural, and economic contexts of the Late Antique and Early Medieval periods, roughly AD 400 to 1000. While the evidence is focused on Western Europe, particularly the kingdoms of the Carolingians and Ottonians, which occupied large parts of what are today France, Germany, the Low Countries, and northern Italy, and kingdoms on the British Isles, Kreiner deftly weaves in sources from across Europe, stretching to the Islamic lands that were in continuous contact with their Christian counterparts.In her introduction, Kreiner stresses that the flexibility of pigs resulted in dynamic ecological systems in early medieval Europe. Human communities adapted their systems to accommodate pigs, who while potentially highly productive could also be highly unruly. This plays out in chapter 1, which underscores the distinctions medieval people drew between wild boar and domestic pig, the variability of landscapes that swine could be raised on, and attempts to control unwanted pig behaviors.The micro-universe of pig husbandry is then set within the much larger context of medieval philosophy in chapter 2. In this chapter, pigs scarcely appear—and yet the chapter puts the pig and its Christianization (which is discussed later) into the intellectual context of the age through a highly accessible explanation of medieval notions of environmental connectivity and complexity.Chapter 3 gets back to the pigs and their landscapes. Kreiner approaches swine husbandry as extracting value out of the landscape or, as she calls it, “salvaging.” Through their ability to turn found foods in the environment into food on human tables, pigs made the landscape productive for people. How they did this—by forest foraging, pasture grazing, or stall feeding—varied according to ecological and economic conditions. Kreiner brings together an impressive collection of sources to explain that variability.In chapter 4, the focus is on the assemblage of humans and pigs and the social groups that were created and modified by those relations. The section on swineherds in particular gives a fascinating behind-the-scenes look at the economic and social status of those closest to pigs. She also shows how pork consumption was a Roman tradition, which had both ideological and practical implications, for example in the provisioning of soldiers with pork through taxes. Chapter 5 starts with the pig as Roman animal and then discusses how the pig became associated with Christians, both in symbolic and dietary forms. Kreiner stresses the counterintuitive connections here, as the pig takes on both diabolical natures and Christian conviction. The legions of pigs and Legion in pigs are co-constituted.Kreiner's book is written with non-medievalists in mind—she elucidates time-specific social and legal terms so that they are understandable without a background in the period. She finds just the right balance of using source materials to support her arguments without getting bogged down in details. Her writing style is a delight to read. This book demonstrates how medieval environmental and agricultural history can be written as a history of ideas and culture with wide appeal.

Does frequency of protein supplementation affect performance of cattle under grazing in tropical pastures?

Our objective was to evaluate the effects of protein supplementation frequency on performance and voluntary intake of cattle under grazing in tropical pastures by using a meta-analytical approach. The dataset used to evaluate the voluntary intake was compiled from 18 experiments carried out in Brazil between 2009 and 2021, totaling 75 treatment means. In order to evaluate the animal performance, treatment means were collected from 19 experiments carried out in Brazil between 2003 and 2018, totaling 69 treatment means. The data were analyzed using meta-analysis techniques, considering the random effect of the experiments on the model parameters. There was no effect of supplementation (P ≥ 0.11) or supplementation frequency (P ≥ 0.18) on forage intake and dietary digested organic matter content (DOM). On the other hand, supplementation increased (P < 0.01) total intake, dietary crude protein (CP) and CP-to-DOM dietary ratio. Supplementation enhanced (P < 0.01) average daily gain (ADG), but without any influence of supplementation frequency (P ≥ 0.84). The ADG increased linearly (P < 0.05) as forage CP increased, but no difference was detected (P > 0.05) among supplementation frequencies. The additional weight gain (AWG) caused by supplementation decreased as forage CP increased and became null at 150 g CP/kg dry matter. There was a quadratic pattern (P < 0.01) of the AWG in response to variations in both supplement intake and supplemental CP intake, but no effect of different frequencies was detected on this variable (P > 0.05). Maximal responses occur when 5.0 g of supplement and 1.14 g of supplemental CP per kg BW were provided. Reducing protein supplementation frequency down to thrice a week does not affect voluntary intake and performance of cattle under grazing in tropical pastures. There is a positive response to protein supplementation on animal performance even with medium to high-quality forages. However, that response decreases as forage CP increases and becomes null at 150 CP/kg dry matter.

Maize cropping degrades soil hydraulic properties relative to grazed pasture in two contrasting soils

Soil hydraulic properties (SHPs), including available water content and near-saturated hydraulic conductivity (Kns), affect hydrological and biochemical processes. The SHPs information is crucial to agricultural water management. The objective of this study using paired sites was to investigate the effects of land use on SHPs in two contrasting soil orders. Soil water retention curves and Kns at three soil depths (0–10, 10–20 and 20–30 cm) were measured under two land uses (pasture, consisting of a rye grass [Lolium perenne L.] and white clover [Trifolium repens L.] mix, and maize [Zea mays L.] cropping > 10 years) in Waikato, New Zealand. For each land use, two soil orders with contrasting soil structural vulnerability were selected: less vulnerable Allophanic soil and more vulnerable Gley soil. Compared with pasture, maize cropping reduced macroporosity, readily available water capacity and Kns of 0–30 cm, and the effect was greater in the deep layer (20–30 cm). This indicated that maize cropping practices result in greater structural degradation to soils compared with pasture, which include the potential for greater subsoil compaction. There was no land use by soil order interaction effect on SHPs, suggesting that the relative SHP degradation under maize cropping compared with pasture grazing was not associated with soil structural vulnerability. Our study emphasised that long-term continuous cropping with maize on the more vulnerable soil (i.e. Gley soil) resulted in the poorest soil physical health.

Spatially discrete disturbance processes enhance grassland floral resources

Abstract Grasslands provide essential floral resources for both managed and wild pollinators. However, grassland flowers in remaining native landscapes are threatened due to non‐native plant invasions and alterations to historic disturbance regimes such as fire and grazing. The potential for managed disturbance to promote grassland floral resources remains unclear. Fire and grazing historically occurred interactively, but uniform application of each may be a detriment to floral resources and the pollinators depending on them. Though fire can increase resources available to plants and stimulate flowering, it initially destroys floral resources and may delay flower availability. Similarly, grazing removes competitors of flowering plants, but destroys flower heads. To address this knowledge gap, we investigated the impacts of rotational fire and cattle grazing (patch‐burn grazing with one and two seasons of fire per year) versus traditional season‐long grazing with no fire on floral resources in mixed‐grass prairie. In patch‐burn treatments, part of each pasture is burned each year, which focuses grazing activity due to the high‐quality regrowth. We aimed to use fire to remove litter around flowering plants while also sheltering established flower heads from grazing pressure by directing cattle away from regenerating forbs in unburned portions of the landscape. Over two summers, we performed weekly flower surveys in season‐long grazing and patch‐burn grazing pastures. We analysed total seasonal floral resources, maximum floral abundance and seasonal species richness between treatments. Over 2 years, we surveyed 1,238,241 ramets of 160 species, focusing on 36 common species for individual analysis. We found broad positive associations between patch‐burn grazing and total seasonal flower abundance, maximum flower abundance and species richness compared to traditional management. In most cases, patch‐burn grazing with dormant and growing season fires produced higher floral abundance, total seasonal floral resources and species richness than patch‐burning with dormant season fires alone, suggesting benefits of increased levels of pyrodiversity. Synthesis and applications. Under increasing pressure to manage for declining pollinators, rangeland managers must consider strategies to enhance floral resources within the context of livestock production goals. The spatiotemporal interaction of cattle grazing and fire shows promise for promoting floral resource abundance and diversity.

Unravelling opportunities, synergies, and barriers for enhancing silvopastoralism in the Mediterranean

Silvopastoral systems combine wood perennials with forage and livestock. These multipurpose wood-pasture habitats represent an important part of European bio-cultural and ecological heritage. However, their gradual disappearance due to processes of farm abandonment and intensification as well as forestry abandonment threatens biodiversity conservation and bio-cultural heritages. The behaviours of forest owners and livestock farmers determine the success of silvopastoral systems since a productive coherence between forest management and livestock grazing is required for their optimal functioning. In this study, we investigate the livestock farmers’ and forest owners’ attitudes and opinions towards wood pasture grazing and their relationship with structural factors and farming objectives in two Spanish regions. We used data collected through surveys to identify opportunities, synergies, and barriers in the integration of these actors in joint silvopastoralism. The results reveal a relationship between production objectives and positive attitudes towards silvopastoralism and the environmental functions provided by this activity, in both farmers and forest owners. Cattle farmers express a greater economic interest in wood pastures, as compared to sheep farmers who perceive more difficulties in using them. Acknowledgement of the role of grazing in landscape maintenance is positively correlated with a wide spectrum of objectives of forest owners, from the economic-productivist to the more altruistic profiles. The most synergies are found between cattle farmers and small forest owners for joint silvopastoral management. However, the incorporation of sheep grazing is advisable for the sustainable management of these systems, and hence additional efforts may be required to integrate such farming systems into silvopastoral management. As it currently stands, the EU Common Agricultural Policy appears to be inadequate for maintaining silvopastoral systems.

211 Greenhouse Gas Emissions from Two Beef Systems from Birth to Slaughter in Eastern Nebraska

Abstract Greenhouse gas emissions from a conventional (CONV) pasture-based cattle production system with cows wintered on corn residue and summer grazing of brome pasture was compared with partial-confinement system (ALT) with cows and calves in a drylot during the summer and grazed cover crops and corn residue over the fall and winter. Four groups of 20 cows were in each system. Eddy covariance methods were used to measure emissions from grazed areas (corn residue and pasture) and pen chambers were used to measure emissions from feedlot pens (cows and calves). Cattle from the CONV system produced more CH4 and CO2 but produced more beef per cow exposed (321 and 303 kg HCW for CONV and ALT, respectively). Measured CH4 and modeled N2O emissions totaled 7.5 ± 0.3 and 7.4 ± 0.3 kg CO2e kg-1 HCW for CONV and ALT production, respectively. There was a measured uptake of 233 g C m-2 and 98 g C m-2 from brome pasture and cover crop, respectively. Accounting for CH4 and N2O emissions using global warming potential (GWP) of 23 and 298 resulted in a net sink of 0.7 ± 0.2 kg CO2e kg-1 HCW for CONV and source of 16.7 ± 1.5 kg CO2e kg-1 HCW for ALT. The same calculation using global warming potential (GWP) of 4 and 234 resulted in a net sink of 10.9 ± 1.0 kg CO2e kg-1 HCW for CONV and source of 7.1 ± 1.5 kg CO2e kg-1 HCW for ALT. Carbon sequestration from perennial grasslands in the CONV was enough to offset all emissions and biogenic CO2 and the annual forage grazed in the ALT system offset 33 to 72% of systems emissions depending on GWP metric used.

Riparian fungal communities respond to land-use mediated changes in soil properties and vegetation structure

PurposeOwing to their topographic location and nutrient rich soils, riparian forests are often converted to pastures for grazing. In recent decades, remnant riparian forests cleared for grazing pastures have been restored with native species. The impacts of such land-use changes on soil fungal communities are unclear, despite the central roles that soil fungi play in key ecosystem processes. We investigated how soil fungal taxonomic and functional composition are affected by land-use change at different depths, and if variation in soil fungal communities is related to edaphic properties and extant vegetation.MethodsThe study was conducted in six waterways in south-eastern Australia, each comprising three land-use types: remnant riparian forest, cleared forest converted to pasture, and pastures restored with native plants. We surveyed three strata of vegetation and sampled top-soil and sub-soil to characterise physicochemical properties and soil fungal communities. ITS1 region sequences were used to assign soil fungal taxonomic and functional composition.ResultsFungal taxonomic and functional composition infrequently varied with land-use change or soil depth. Overall, environmental properties (soil and vegetation) explained 35–36% of variation in both fungal taxonomic and functional composition. Soil fungal taxonomic composition was related to soil fertility (N, P, K, pH and Ca) and ground cover characteristics, whereas functional composition was related to clay content, sub-canopy cover and tree basal area.ConclusionAcross the six studied waterways, fungal taxonomic and functional composition were more strongly associated with land-use mediated changes in site-scale soil physicochemical properties and vegetation structure than broad-scale classes of land-use type.

CO2 fluxes from three different temperate grazed pastures using Eddy covariance measurements

Grasslands cover around 25% of the global ice-free land surface, they are used predominantly for forage and livestock production and are considered to contribute significantly to soil carbon (C) sequestration. Recent investigations into using ‘nature-based solutions’ to limit warming to <2 °C suggest up to 25% of GHG mitigation might be achieved through changes to grassland management. In this study we evaluate pasture management interventions at the Rothamsted Research North Wyke Farm Platform, under commercial farming conditions, over two years and consider their impacts on net CO2 exchange. We investigate if our permanent pasture system (PP) is, in the short-term, a net sink for CO2 and whether reseeding this with deep-rooting, high-sugar grass (HS) or a mix of high-sugar grass and clover (HSC) might increase the net removal of atmospheric CO2. In general CO2 fluxes were less variable in 2018 than in 2017 while overall we found that net CO2 fluxes for the PP treatment changed from a sink in 2017 (−5.40 t CO2 ha−1 y−1) to a source in 2018 (6.17 t CO2 ha−1 y−1), resulting in an overall small source of 0.76 t CO2 ha−1 over the two years for this treatment. HS showed a similar trend, changing from a net sink in 2017 (−4.82 t CO2 ha−1 y−1) to a net source in 2018 (3.91 t CO2 ha−1 y−1) whilst the HSC field was a net source in both years (3.92 and 4.10 t CO2 ha−1 y−1, respectively). These results suggested that pasture type has an influence in the atmospheric CO2 balance and our regression modelling supported this conclusion, with pasture type and time of the year (and their interaction) being significant factors in predicting fluxes.

Management Zones in Pastures Based on Soil Apparent Electrical Conductivity and Altitude: NDVI, Soil and Biomass Sampling Validation

The intensification of the Montado mixed ecosystem (agro–silvo–pastoral) is a current endeavor in the context of promoting the sustainability of extensive livestock production in the Mediterranean region. Increased pasture productivity and extensive animal production involves the use of technologies to monitor spatial variability and to implement differentiated management of pasture grazing, fertilization or soil amendment. An intermediate step should lead to the identification and demarcation of areas with similar characteristics (soil and/or crop development), known as homogeneous management zones (HMZ) to implement site-specific management strategies. In this study, soil apparent electrical conductivity (ECa) and altimetry surveys were carried out in six experimental pasture fields with a non-contact electromagnetic induction sensor (EM38) associated with a Global Navigation Satellite System (GNSS) receiver. These ECa and topographic maps were used in geostatistical analyses for designing and establishing final classification maps with three HMZ (less, intermediate and more potential). The normalized difference vegetation index (NDVI), obtained from a proximal optical sensor, and soil and biomass sampling were used to validate these HMZ. From a practical perspective, these HMZ are the basis for preparation of fertilizer prescription maps and use of variable rate technology (VRT) in a Precision Agriculture project.

Developments in nutrition for pasture-based cattle and sheep systems in Ireland

For ruminant production systems, the requirement to meet specific nutrient targets in the animal’s diet must be balanced with the aim of achieving high utilisation of forage in the overall feed budget. A focus of research and extension in an Irish industry context has been to meet these objectives using grazed pasture as the predominant forage source. This has prompted investigation to improve understanding of the components defining forage nutritive value, as well as the management factors affecting its intake and utilisation by animals. Similarly, quantifying the animal performance responses to varying type, rate and timing of dietary supplementation has been an important area of investigation. This review summarises some of the principal outcomes and developments over recent years across beef, sheep and dairy production systems. In addition, ruminant production systems are increasingly challenged to reduce potential environmental impacts by mitigating nutrient and gaseous emissions across their production cycles. Current and emerging research with regard to this issue, and enteric methane production in particular, is discussed.