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91.
92.
Short communication: The effect of diarrhea and navel inflammation on the lying behavior of veal calves 总被引:1,自引:0,他引:1
M.J. Studds L.L. Deikun D.E. Sorter J.A. Pempek K.L. Proudfoot 《Journal of dairy science》2018,101(12):11251-11255
Many veal calves arrive to growing facilities with diseases, including diarrhea and navel inflammation. Observing neonatal calf behavior, such as lying behavior, can be used to better detect and determine the implications of these diseases. The aim of this study was to determine the effect of navel inflammation and diarrhea on lying behavior in neonatal veal calves. This study was part of a larger experiment that included a total of 360 male Holstein calves from 3 cohorts; from these calves, we selected a subset of 125 calves (every third calf as they entered the barn) to be fitted with 3-dimensional accelerometers (Hobo Pendant G data loggers; Onset Computer Corp., Bourne, MA) on 1 hind leg to continuously measure lying time, number of lying bouts, and lying bout duration. Calves were housed individually on slatted flooring (Tenderfoot; Tandem Products Inc., Minneapolis, MN) in 3 rooms of a mechanically ventilated barn. Health exams were conducted twice weekly for 2 wk starting the day after arrival. Exams included rectal temperature, navel score (0 = normal, 1 = mildly inflamed, 2 = moderately inflamed, 3 = severely inflamed), and fecal score (0 = normal, 1 = semiformed, 2 = loose, 3 = watery). Calves were considered to have navel inflammation (n = 22) or diarrhea (n = 15) if they scored ≥2 during at least 3 of the 4 health exams. The lying behavior of these calves was compared with that of normal calves (n = 18) that had no signs of illness and rectal temperatures <39.4°C during at least 3 of the 4 health exams. Data were analyzed using a repeated-measures ANOVA; models included cohort (1, 2, or 3), health status (normal, navel inflammation, or diarrhea), week (1 or 2), and a health by week interaction. There was an effect of health status on lying time, whereby normal calves spent more time lying compared with calves with inflamed navels and tended to spend more time lying compared with calves with diarrhea. There was no effect of health status on the number of lying bouts per day or on the duration of lying bouts. There were no health by week interactions. Results indicate that neonatal veal calves with navel inflammation and diarrhea may be less comfortable than calves without these conditions. Veal producers should consider adapting their facilities to create more comfortable lying environments to help calves better recover from disease, such as by adding a hospital pen with comfortable bedding. 相似文献
93.
J. Deming D. Gleeson T. ODwyer J. Kinsella B. OBrien 《Journal of dairy science》2018,101(10):9527-9543
With the cessation of milk quotas in the European Union, dairy herd sizes increased in some countries, including Ireland, with an associated increase in labor requirement. Second to feed costs, labor has been identified as one of the highest costs on pasture-based dairy farms. Compared with other European Union countries, Ireland has historically had low milk production per labor unit; thus, optimization of labor efficiency on farm should be addressed before or concurrently with herd expansion. The objective of this study was to quantify current levels of labor input and labor efficiency on commercial pasture-based dairy farms and to identify the facilities and management practices associated with increased labor efficiency. Thirty-eight dairy farms of varying herd sizes, previously identified as labor-efficient farms, were enrolled on the study and data were collected over 3 consecutive days each month over a 12-mo period, starting in May 2015 and finishing in August of 2016. This was achieved through the use of a smartphone application. For analysis purposes, farms were categorized into 1 of 3 herd size categories (HSC): farms with <150 cows (HSC 1), 150–249 cows (HSC 2), or ≥250 cows (HSC 3). Overall farm labor input increased with HSC with 3,015, 4,499, and 6,023 h worked on HSC 1, 2, and 3, respectively. A higher proportion of work was carried out by hired staff as herd size increased. Labor efficiency was measured as total hours input to the dairy enterprise divided by herd size. Labor efficiency improved as herd size increased above 250 cows with 17.3 h/cow per yr observed for HSC 3; labor efficiency was similar for HSC 1 and 2, at 23.8 and 23.3 h/cow per yr, respectively. A large range of efficiency was observed within HSC. The labor requirements had a distinct seasonal pattern across the 3 HSC with the highest input observed in springtime (February to April) primarily due to calving and calf-care duties, milking, and winter feeding. The lowest input was observed in wintertime (November to January) when cows were dry. Particular facilities and management practices were associated with efficiency within certain tasks, the most notable in regard to milking and winter feeding practices. Additionally, the most efficient farms used contractors to perform a higher proportion of machinery work on farm than the least efficient farms. 相似文献
94.
95.
Bryan D. Paulsen Ruiheng Wu Christopher J. Takacs Hans-Georg Steinrück Joseph Strzalka Qingteng Zhang Michael F. Toney Jonathan Rivnay 《Advanced materials (Deerfield Beach, Fla.)》2020,32(40):2003404
The structure and packing of organic mixed ionic–electronic conductors have an especially significant effect on transport properties. In operating devices, this structure is not fixed but is responsive to changes in electrochemical potential, ion intercalation, and solvent swelling. Toward this end, the steady-state and transient structure of the model organic mixed conductor, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), is characterized using multimodal time-resolved operando techniques. Steady-state operando X-ray scattering reveals a doping-induced lamellar expansion of 1.6 Å followed by 0.4 Å relaxation at high doping levels. Time-resolved operando X-ray scattering reveals asymmetric rates of lamellar structural change during doping and dedoping that do not directly depend on potential or charging transients. Time-resolved spectroscopy establishes a link between structural transients and the complex kinetics of electronic charge carrier subpopulations, in particular the polaron–bipolaron equilibrium. These findings provide insight into the factors limiting the response time of organic mixed-conductor-based devices, and present the first real-time observation of the structural changes during doping and dedoping of a conjugated polymer system via X-ray scattering. 相似文献
96.
Real-Time Systems - In this paper we point to some errors in recent paper by Asyaban et al. in which they devise an exact schedulability test. These errors are critical for the correct operation of... 相似文献
97.
Iranian Polymer Journal - Composites derived from petroleum sources like epoxy, unsaturated polyester and phenolics have limitations due to non-biodegradability toxicity which have harmful effects... 相似文献
98.
Ilaria Patruno Dr. Dawn Thompson Dr. Sergio Dall'Angelo Prof. Albert D. Windhorst Dr. Danielle J. Vugts Dr. Alex J. Poot Dr. Nimesh Mody Prof. Matteo Zanda 《ChemMedChem》2020,15(16):1579-1590
Fenretinide (4-HPR) is a synthetic derivative of all-trans-retinoic acid (ATRA) characterised by improved therapeutic properties and toxicological profile relative to ATRA. 4-HPR has been mostly investigated as an anti-cancer agent, but recent studies showed its promising therapeutic potential for preventing metabolic syndrome. Several biological targets are involved in 4-HPR's activity, leading to the potential use of this molecule for treating different pathologies. However, although 4-HPR displays quite well-understood multitarget promiscuity with regards to pharmacology, interpreting its precise physiological role remains challenging. In addition, despite promising results in vitro, the clinical efficacy of 4-HPR as a chemotherapeutic agent has not been satisfactory so far. Herein, we describe the preparation of a library of 4-HPR analogues, followed by the biological evaluation of their anti-cancer and anti-obesity/diabetic properties. The click-type analogue 3 b showed good capacity to reduce the amount of lipid accumulation in 3T3-L1 adipocytes during differentiation. Furthermore, it showed an IC50 of 0.53±0.8 μM in cell viability tests on breast cancer cell line MCF-7, together with a good selectivity (SI=121) over noncancerous HEK293 cells. Thus, 3 b was selected as a potential PET tracer to study retinoids in vivo, and the radiosynthesis of [18F] 3b was successfully developed. Unfortunately, the stability of [18F] 3b turned out to be insufficient to pursue imaging studies. 相似文献
99.
Kirillova I. A. Tarasova L. S. Fedorova E. N. Gusev A. O. Simakov D. A. Nagibin G. E. 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(4):849-856
Protection of Metals and Physical Chemistry of Surfaces - The resistance of different TiB2 powders to oxidative degradation is studied by synchronous thermal analysis. The temperature dependence of... 相似文献
100.