Integrating Grazing with 2,4-D and Florpyrauxifen to Control Broadleaf Weeds and Maintain Red Clover Productivity in Grass-Legume Pastures

In grass-legume pastures, 2,4-D-amine + florpyrauxifen-benzyl controls broadleaf weeds but red clover (Trifolium pratense L.) is eliminated. Grazing within a week prior to herbicide application is likely to reduce leaf surface area and may reduce red clover injury and maintain productivity. Experiments were conducted in 2020 and in 2021 to determine if red clover could be productive when 560 g ae ha-1 2,4-D-amine + 6.3 g ae ha-1 of florpyrauxifen-benzyl with 1% v/v methylated seed oil applied in the spring was grazed before or after herbicide application. Grazing timings occurred 6, 4, or 2 days prior to herbicide application, the day of application, or 6 days after application. Grazing timing did not affect productivity or cover of red clover, white clover, forage grasses, broadleaf weeds, or annual grasses. In contrast, aboveground biomass of broadleaf weeds, red clover, and white clover was \u3e55, 56, and 44% less, respectively, in 2,4-D-amine + florpyrauxifenbenzyl treated pasture than nontreated pasture. Less clover and broadleaf weed biomass in herbicide treated pasture was associated with 16% more perennial grass biomass and no changes in total forage productivity. Results suggest that all grazing timings applied with 2,4-D-amine + florpyrauxifen-benzyl provided effective weed control that persisted more than 1 year with only partial injury to red clover populations. Grazing in concert with herbicide applications improves herbicide selectivity of preferentially grazed species, while improved from conventional standards practicality to producers is still unknown

Integrating Grazing with 2,4-D and Florpyrauxifen to Control Broadleaf Weeds and Maintain Red Clover Productivity in Grass-Legume Pastures

In grass-legume pastures, 2,4-D-amine + florpyrauxifen-benzyl controls broadleaf weeds but red clover (Trifolium pratense L.) is eliminated. Grazing within a week prior to herbicide application is likely to reduce leaf surface area and may reduce red clover injury and maintain productivity. Experiments were conducted in 2020 and in 2021 to determine if red clover could be productive when 560 g ae ha-1 2,4-D-amine + 6.3 g ae ha-1 of florpyrauxifen-benzyl with 1% v/v methylated seed oil applied in the spring was grazed before or after herbicide application. Grazing timings occurred 6, 4, or 2 days prior to herbicide application, the day of application, or 6 days after application. Grazing timing did not affect productivity or cover of red clover, white clover, forage grasses, broadleaf weeds, or annual grasses. In contrast, aboveground biomass of broadleaf weeds, red clover, and white clover was \u3e 55, 56, and 44% less, respectively, in 2,4-D-amine + florpyrauxifenbenzyl treated pasture than nontreated pasture. Less clover and broadleaf weed biomass in herbicide treated pasture was associated with 16% more perennial grass biomass and no changes in total forage productivity. Results suggest that all grazing timings applied with 2,4-D-amine + florpyrauxifen-benzyl provided effective weed control that persisted more than 1 year with only partial injury to red clover populations. Grazing in concert with herbicide applications improves herbicide selectivity of preferentially grazed species, while improved from conventional standards practicality to producers is still unknown

Effectiveness and Cost of Shrub Removal Methods in Degraded Woodlands Being Converted to Silvopasture

Transforming degraded woodlands to silvopasture is of interest in the Midwestern USA as it increases profitability of farms and benefits animal health. Invasive shrubs within woodlands, however, are a major obstacle to silvopasture establishment. Research was undertaken to evaluate the effectiveness, cost and resulting herbaceous canopy light interception of common brush-control methods when used alone or integrated over a two-year timeframe. Five treatments were established in a randomized complete block design. In the first year, treatments were either forestry mowed (mow) or rotationally grazed by goats (goats) at a stocking density of 5700 to 6000 kg per hectare. In the second year, mow and goat treatments were either grazed by goats again or shrubs were treated with a herbicide (herb). These were compared to a non-treated control. Costs of each treatment were calculated based on labor, equipment/supplies, and contracts. Vegetation composition and herbaceous canopy light interception were evaluated the summer after treatments were implemented. Forestry mowing followed by herbicide was the least expensive treatment at $1833/ha, while goats were 72% higher. Light interception by the herbaceous canopy was not reduced by goats, but mowing followed by goats increased light interception such that it was greater than repeated goat grazing (p\u3c0.05). While shrubs were initially impacted by treatments, resprouting resulted in no differences in abundance compared with non-treated controls. Grass abundance was similar in control plots and treatments (p\u3e0.05). Forb abundance remained similar in control and goat-grazed treatments but increased in mowed areas. Costs and effectiveness of multi-year treatments will continue to be evaluated through 2024

Defining Mob Grazing in the Upper Midwestern United States

Mob grazing has emerged as an increasingly used management strategy on pasture-based farms throughout the country; however, the practice lacks clear definition among practitioners. We conducted a survey of livestock and dairy producers using some form of rotational grazing in the upper midwestern United States (N = 155) to gather producer-generated definitions, perceptions of benefits and disadvantages, and implementation strategies for mob grazing. The results describe a practice defined by variability and associated with compelling impacts. Implementation of mob grazing differed among producers, although most used it as a strategic tool and not a rigid management strategy

Lower limb joint angle variability and dimensionality are different in stairmill climbing and treadmill walking

The present study tested if the quadratic relationship which exists between stepping frequency and gait dynamics in walking can be generalized to stairmill climbing. To accomplish this, we investigated the joint angle dynamics and variability during continuous stairmill climbing at stepping frequencies both above and below the preferred stepping frequency (PSF). Nine subjects performed stairmill climbing at 80, 90, 100, 110 and 120% PSF and treadmill walking at preferred walking speed during which sagittal hip, knee and ankle angles were extracted. Joint angle dynamics were quantified by the largest Lyapunov exponent (LyE) and correlation dimension (CoD). Joint angle variability was estimated by the mean ensemble standard deviation (meanSD). MeanSD and CoD for all joints were significantly higher during stairmill climbing but there were no task differences in LyE. Changes in stepping frequency had only limited effect on joint angle variability and did not affect joint angle dynamics. Thus, we concluded that the quadratic relationship between stepping frequency and gait dynamics observed in walking is not present in stairmill climbing based on the investigated parameters

Algebraic Properties of Qualitative Spatio-Temporal Calculi

Qualitative spatial and temporal reasoning is based on so-called qualitative calculi. Algebraic properties of these calculi have several implications on reasoning algorithms. But what exactly is a qualitative calculus? And to which extent do the qualitative calculi proposed meet these demands? The literature provides various answers to the first question but only few facts about the second. In this paper we identify the minimal requirements to binary spatio-temporal calculi and we discuss the relevance of the according axioms for representation and reasoning. We also analyze existing qualitative calculi and provide a classification involving different notions of a relation algebra.Comment: COSIT 2013 paper including supplementary materia

Thinking inside the box: a comprehensive spatial representation for video analysis.

Successful analysis of video data requires an integration of techniques from KR, Computer Vision, and Machine Learning. Being able to detect and to track objects as well as extracting their changing spatial relations with other objects is one approach to describing and detecting events. Different kinds of spatial relations are important, including topology, direction, size, and distance between objects as well as changes of those relations over time. Typically these kinds of relations are treated separately, which makes it difficult to integrate all the extracted spatial information. We present a uniform and comprehensive spatial representation of moving objects that includes all the above spatial/temporal aspects, analyse different properties of this representation and demonstrate that it is suitable for video analysis

Response of the meso- and macro-zooplankton community to long-term environmental changes in the southern North Sea

Abstract The North Sea (NS) is changing rapidly. Temporal variations in fishing intensity and eutrophic conditions, along with the ongoing impact of climate change, act in synergy resulting in modifications in marine communities. Although zooplankton has been extensively investigated, studies often ignore the large-sized meso- and macro-zooplankton (&amp;gt;500 µm), including holoplankton and meroplankton taxa. Here, we examined changes in abundances and community structure of these organisms between 1975 and 2018, using univariate and multivariate analysis, at different taxonomic levels. Abrupt changes in the abundances of (sub)communities occurred during different time periods and resulted in a significant restructuration of the entire community in 2006. These changes were consistent with the regime shifts reported in the NS and were a consequence of the environmental pressures on the whole community or on specific subcommunities. In the long term, the community shifted from higher abundances of hydrozoans and holoplankton taxa to an increasing abundance of decapods. Furthermore, we reveal the environmental variables that most explain the variability in the community dynamics, highlighting the importance of temperature and top-down processes. Our study underlines the relevance of investigations at different taxonomic levels, which elucidates how distinct responses to environmental changes ultimately shape the entire community structure.</jats:p

Ancestral and derived attributes of the dlx gene repertoire, cluster structure and expression patterns in an African cichlid fish

<p>Abstract</p> <p>Background</p> <p>Cichlid fishes have undergone rapid, expansive evolutionary radiations that are manifested in the diversification of their trophic morphologies, tooth patterning and coloration. Understanding the molecular mechanisms that underlie the cichlids' unique patterns of evolution requires a thorough examination of genes that pattern the neural crest, from which these diverse phenotypes are derived. Among those genes, the homeobox-containing <it>Dlx </it>gene family is of particular interest since it is involved in the patterning of the brain, jaws and teeth.</p> <p>Results</p> <p>In this study, we characterized the <it>dlx </it>genes of an African cichlid fish, <it>Astatotilapia burtoni</it>, to provide a baseline to later allow cross-species comparison within Cichlidae. We identified seven <it>dlx </it>paralogs (<it>dlx1a</it>, <it>-2a</it>, <it>-4a</it>, <it>-3b</it>, <it>-4b</it>, <it>-5a </it>and <it>-6a</it>), whose orthologies were validated with molecular phylogenetic trees. The intergenic regions of three <it>dlx </it>gene clusters (<it>dlx1a-2a</it>, <it>dlx3b-4b</it>, and <it>dlx5a-6a</it>) were amplified with long PCR. Intensive cross-species comparison revealed a number of conserved non-coding elements (CNEs) that are shared with other percomorph fishes. This analysis highlighted additional lineage-specific gains/losses of CNEs in different teleost fish lineages and a novel CNE that had previously not been identified. Our gene expression analyses revealed overlapping but distinct expression of <it>dlx </it>orthologs in the developing brain and pharyngeal arches. Notably, four of the seven <it>A. burtoni dlx </it>genes, <it>dlx2a</it>, <it>dlx3b</it>, <it>dlx4a </it>and <it>dlx5a</it>, were expressed in the developing pharyngeal teeth.</p> <p>Conclusion</p> <p>This comparative study of the <it>dlx </it>genes of <it>A. burtoni </it>has deepened our knowledge of the diversity of the <it>Dlx </it>gene family, in terms of gene repertoire, expression patterns and non-coding elements. We have identified possible cichlid lineage-specific changes, including losses of a subset of <it>dlx </it>expression domains in the pharyngeal teeth, which will be the targets of future functional studies.</p

Repeated high doses of avermectins cause prolonged sterilisation, but do not kill, Onchocerca ochengi adult worms in African cattle

BACKGROUND: Ivermectin (Mectizan™, Merck and CO. Inc.) is being widely used in the control of human onchocerciasis (Onchoverca volvulus) because of its potent effect on microfilariae. Human studies have suggested that, at the standard dose of 150 μg/kg an annual treatment schedule of ivermectin reversibly interferes with female worm fertility but is not macrofilaricidal. Because of the importance of determining whether ivermectin could be macrofilaricidal, the efficacy of high and prolonged doses of ivermectin and a related avermectin, doramectin, were investigated in cattle infected with O. ochengi. METHODS: Drugs with potential macrofilaricidal activity, were screened for the treatment of human onchocerciasis, using natural infections of O. ochengi in African cattle. Three groups of 3 cows were either treated at monthly intervals (7 treatments) with ivermectin (Ivomec(®), Merck and Co. Inc.) at 500 μg/kg or doramectin (Dectamax(®), Pfizer) at 500 μg/kg or not treated as controls. Intradermal nodules were removed at 6 monthly intervals and adult worms were examined for signs of drug activity. RESULTS: There was no significant decline in nodule diameter, the motility of male and female worms, nor in male and female viability as determined by the ability to reduce tetrazolium, compared with controls, at any time up to 24 months from the start of treatments (mpt). Embryogenesis, however, was abrogated by treatment, which was seen as an accumulation of dead and dying intra-uterine microfilariae (mf) persisting for up to 18 mpt. Skin mf densities in treated animals had fallen to zero by <3 mpt, but by 18 mpt small numbers of mf were found in the skin of some treated animals and a few female worms were starting to produce multi-cellular embryonic stages. Follow-up of the doramectin treated group at 36 mpt showed that mf densities had still only regained a small proportion of their pre-treatment levels. CONCLUSION: These results have important implications for onchocerciasis control in the field. They suggest that ivermectin given at repeated high does may sterilise O. volvulus female worms for prolonged periods but is unlikely to kill them. This supports the view that control programmes may need to continue treatments with ivermectin for a period of decades and highlights the need to urgently identify new marcofiliaricidal compounds