The aim of this study was to investigate the short-term responses of dairy cows during periods of change in the concentrate allowance in an automatic milking system. The experiment had a design with a 2 × 2 factorial arrangement including 2 types of concentrates and 2 amounts of concentrates (type O: mix of pelleted concentrate and steamrolled, acidified barley; type S: pelleted) in amounts of 3 and 6 kg/d. The experiment length was 11 wk. The concentrate type changed between wk 6 and 7 and included both increase and decrease in concentrate allowance for each concentrate type. The concentrate allowance was changed by 0.5 kg/d over 6 d. The 96 cows (48 Danish Jersey, 48 Danish Holstein) included in the experiment were blocked according to breed, parity, and days in milk, and randomly divided into 8 groups of treatment order. The cows visited the automatic milking unit more often when concentrate type O was offered, but not when an increased concentrate allowance was provided. The changes in concentrate intake and partial mixed ration (PMR) eating time showed a symmetrical pattern between the periods of increasing allowance and decreasing allowance. However, PMR intake and milk yield varied in the magnitude of the responses, indicating that these responses may not be driven by the same underlying mechanisms during increase and decrease in concentrate allowance. The daily lying time increased and the PMR eating rate decreased during periods of both increase and decrease in concentrate allowance. We found no significant change in milk yield during increase in concentrate allowance, despite a higher milk yield during periods with constant concentrate allowance at the high concentrate amount; however, the milk yield decreased during periods of decrease in concentrate allowance. Visit frequency, lying time, and steps changed during periods of changes in concentrate allowance without showing any differences at the constant concentrate allowance. In conclusion, these results indicate that it may be difficult to adjust the individual concentrate allowance based on the short-term responses of the cow.
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http://dx.doi.org/10.3168/jds.2018-14624 | DOI Listing |
J Dairy Sci
January 2025
Department of Animal Biosciences, University of Guelph, Guelph, Ontario, N1G 2W1, Canada. Electronic address:
Provision of supplemental concentrate in an automated milking system (AMS) is commonly used to encourage voluntary attendance, however, the motivation to voluntarily milk is highly variable between cows. The objectives of this study were to determine if dairy cow personality is associated with: 1) their short-term response to changes in factors believed to motivate voluntary AMS visits such as udder pressure and provision of supplemental feed (modulated by longer milking intervals or removal of AMS concentrate, respectively); and 2) their milking activity, production, and feeding behavior after returning to pre-treatment AMS milking interval and concentrate feed settings (i.e.
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January 2025
Chair of Engineering Hydrology and Water Management, Technical University of Darmstadt, Darmstadt, Germany. Electronic address:
River quality management involves complex challenges due to inherent uncertainties in various parameters, especially when dealing with controllable and uncontrollable pollutants. This study integrates a finite volume approach, called SEF (symmetric exponential function), with Monte Carlo simulations in MATLAB to solve the advection-dispersion equation, focusing on evaluating river quality protection tools by considering failure probability (P). Critical specifications for maintaining reliable river ecosystem performance are identified.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
State Key Lab of Geohazard prevention & Geoenvironment protection, College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, China. Electronic address:
Sulfur nanoparticles (SNPs) and their composites are promising for heavy metal adsorption, yet current SNPs often lack surface S, leading to low affinity toward heavy metal and ease of aggregation. Here, we report a simple light-driven method for facile prepare SNPs with surfaces enriched with S and in-situ load them onto graphene oxide (GO) to fabricate GO-S composites. Under illumination, the O generated by photosensitizer phloxine B was able to oxidize S into elemental SNPs.
View Article and Find Full Text PDFChina CDC Wkly
December 2024
Chinese Center for Disease Control and Prevention, Beijing, China.
Introduction: Glycidyl methacrylate (GMA) is a widely used industrial polymerization material. Current occupational exposure limits (OELs) for GMA in China show significant disparities compared to those established by international regulatory bodies, including the United States, the European Union, and Japan. A comprehensive revision of GMA exposure limits is crucial for ensuring optimal worker protection.
View Article and Find Full Text PDFEnviron Health Insights
January 2025
Department of Environmental Health Science and Technology, Faculty of Public Health, Health Institute, Jimma University, Jimma, Ethiopia.
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