Mechanical overburdening is a major risk factor that provokes non-infectious claw diseases. Moreover, lameness-causing lesions often remain undetected and untreated. Therefore, prevention of claw tissue overburdening is of interest, especially by analyzing harmful effects within dairy cows’ housing environment. However, objective “on-cow” methods for bovine gait analysis are underdeveloped. The purpose of the study was to apply an innovative mobile pressure sensor system attached at the claws to perform pedobarometric gait analysis. A further goal was the supplementation with accelerative data, generated simultaneously by use of two inertial measurement units (IMUs), attached at metatarsal level. IMU data were analyzed with an automatic step detection algorithm. Gait analysis was performed in ten dairy cows, walking and trotting on concrete flooring and rubber mats. In addition to the basic applicability of the sensor systems and with the aid of the automatic step detection algorithm for gait analysis in cows, we were able to determine the impact of the gait and flooring type on kinematic and kinetic parameters. For pressure sensor output, concrete was associated with significantly (p < 0.001) higher maximum and average pressure values and a significantly smaller contact area, compared to rubber mats. In contrast to walking, trotting led to a significantly higher force, especially under the medial claw. Further, IMU-derived parameters were significantly influenced by the gait. The described sensor systems are useful tools for detailed gait analysis in dairy cows. They allow the investigation of factors which may affect claw health negatively.

Cyanobacteria are ubiquitous aquatic organisms with a remarkable evolutionary history reaching as far as 1.9 Ga. They play a vital role in ecosystems yet also raise concerns due to their association with harmful algal blooms. Understanding the historical patterns and drivers behind these blooms is crucial for effective ecosystem management. Lake-sediment cores are valuable natural environmental archives, recording the histories of such blooms. Among others, phycocyanin, a pigment specific to cyanobacteria, emerges as a promising biomarker for reconstructing past cyanobacterial bloom events. However, due to the physicochemical properties of phycocyanin, there is no validated method available to extract and measure this pigment from complex sediment matrix. This study explores the applicability of hyperspectral imaging (HSI), a non-destructive technique, as a novel approach for high resolution in-situ detection and quantification of phycocyanin in lake sediments. Our experiments show that phycocyanin can be detected by HSI with an absorption trough at 620 nm (relative absorption band depth, RABD₆₂₀). We established a semi-quantitative calibration of the spectral index RABD₆₂₀ by conducting spiking experiments with phycocyanin standard (known phycocyanin mass) on organic-rich and mineral-rich sediments of varying water contents. We also assessed potential interference from chlorophyll a, another photosynthetic pigment, ensuring the reliability of hyperspectral phycocyanin measurements. Our findings demonstrate a significant correlation (R² ranging from 0.37 to 0.997) between the RABD₆₂₀ index and associated phycocyanin amounts in organic-rich and minerogenic sediments. This indicates the potential of the spectral index to directly measure in-situ biomarker concentrations on split sediment cores. Although confounding factors such as water and chlorophyll a content can influence the spectral signal, this method offers a rapid and non-destructive approach for studying historical cyanobacterial blooms in sedimentary records. This opens promising grounds for various applications, including ecosystem-health assessment and environmental change monitoring.

Gegenstand und Ziel Hohe Druckbelastungen der Rinderklauen führen regelmäßig zu Schäden an den Klauengeweben und nachfolgend zu therapiebedürftigen Rusterholz’schen Sohlengeschwüren (RSG). Ein komplizierter Verlauf der RSG kann durch fachgerechte Klauenpflege verhindert werden. In dieser Studie wurde untersucht, wie sich ein an der Außenklaue der Hintergliedmaße vorgenommener stufenloser und keilförmiger Entlastungsschnitt vom Ballen bis zur Sohlenspitze auf die Druckverteilung unter den Klauen der Beckengliedmaße auswirkt und ob eine Veränderung der Druckverteilung zur Lederhautentlastung im Bereich des Defekts führt. Material und Methode Neunzehn isolierte distale Rindergliedmaßen vom Schlachthof (A: unbearbeiteter Zustand) wurden schrittweise bearbeitet (B: funktionelle Klauenpflege, Schritt 1–3; C: Erweiterung der Hohlkehlung und kreisrunde Bohrung zur Simulation eines RSG an der Außenklaue; D: keilförmiger Entlastungsschnitt vom Ballen bis zur Hälfte der Sohlenfläche in Richtung Sohlenspitze; E: keilförmige Erweiterung des Entlastungsschnittes über die gesamte Sohlenfläche bis kurz vor die Sohlenspitze). Zwischen den einzelnen Bearbeitungsschritten wurden die Gliedmaßen mit 200 kg belastet. Die Druckverteilung unter den Klauen wurde mit Drucksensoren gemessen. Außerdem wurden die Klauen auf einer Glasplatte positioniert, was die Beurteilung der Vorwölbung der Lederhaut bzw. des Fettpolsters anhand des Bohrlochs ermöglichte. Ergebnisse In Zustand A lasteten durchschnittlich 63 %, bei Zustand E 30 % der gesamten Kraft auf der Außenklaue. Mit zunehmender Bearbeitung der Klauen verlagerten sich die Druckmaxima vom Ballen- in den Sohlenspitzenbereich. Die relative Belastungsfläche der Innenklaue nahm mit fortschreitender Bearbeitung um bis zu 18,4 % zu. In Zustand E ergab sich im Vergleich zu C eine signifikante Reduzierung der Lederhautvorwölbung im Bereich des künstlichen Sohlendefekts. Schlussfolgerung Der keilförmige Entlastungsschnitt (E) führte an den isolierten Rindergliedmaßen zu einer Außenklauen- und Ballenentlastung und stellt eine Methode zur Defekt- und Lederhautentlastung dar. Klinische Relevanz Der Entlastungsschnitt könnte auch am lebenden Tier eine Druckentlastung der Außenklaue bewirken und so den Krankheitsverlauf von RSG positiv beeinflussen. Objective Overloading or excessive mechanical stress to the claws may damage the sensitive claw tissues and subsequently lead to sole ulcers. Corrective treatment can prevent complications of these sole ulcers. The aim of this study was to investigate the effects of a wedge-shaped relief incision from the bulb to the tip of the outer claw of the pelvic limb on the pressure distribution beneath the pertaining claw. Furthermore, it aimed to clarify whether a change in the pressure distribution would lead to dermal pressure relief in the area of a horn defect. Material and methods Nineteen isolated bovine limbs from an abattoir were gradually trimmed resulting in following stages. A: initial condition; B: functional claw trimming, steps 1–3; C: extension of the model and drill of a circular lesion at the Rusterholz site (outer claw ulcer simulation); D: wedge shaped, weight-relieving incision from the bulb halfway towards the sole tip; E: further extension of the wedge-shaped incision towards the sole tip. The limbs were loaded with 200 kg following each of the procedures. A pressure sensor system was used in order to analyze the pressure distribution beneath the claws. Furthermore, positioning of the claws on a glass plate allowed for an evaluation of corium resp. fat cushion protrusion through the artificial lesion. Results In the untrimmed claws, an average of 63 % of the total force applied rested on the outer claw area. This value decreased to 30 % following step E. Maximum pressure values shifted from the bulb area towards the sole tip with increasing degree of claw trimming. The relative loading area of the inner claw increased to up to 18.4 % following the procedures. The described incision technique (step E) resulted in a significant reduction of corium protrusion through the artificial horn defect in comparison to the claw situation in step C. Conclusion The wedge-shaped, weight-relieving incision (step E) led to pressure reduction in the area of the outer claw and the bulb region in this ex-vivo-study. Therefore, this trimming method may serve to relieve pressure from the vulnerable Rusterholz site as well as providing means for reducing corium compression. Clinical relevance The described trimming method facilitates pressure relief on the outer claw area in live animals. In this, it may exert a positive effect on disease progression in Rusterholz sole ulcers. Received: 05 June 2020 Accepted: 06 October 2020 Publication Date: 26 April 2021 (online) © 2021. Thieme. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany