000151182 001__ 151182
000151182 005__ 20251017144612.0
000151182 0247_ $$2doi$$a10.3389/fphys.2021.707222
000151182 0248_ $$2sideral$$a125862
000151182 037__ $$aART-2021-125862
000151182 041__ $$aeng
000151182 100__ $$aPalacios C.
000151182 245__ $$aA High Cattle-Grazing Density Alters Circadian Rhythmicity of Temperature, Heart Rate, and Activity as Measured by Implantable Bio-Loggers
000151182 260__ $$c2021
000151182 5060_ $$aAccess copy available to the general public$$fUnrestricted
000151182 5203_ $$aSix cows managed under extensive grazing conditions were used to study the effect of moving the animals to a higher grazing density on the circadian rhythms of temperature (T), heart rate (HR), and activity (ACT), which were recorded by implantable bio-loggers. Cows were maintained at a density of 1.5 livestock units per hectare (LSUs/ha; low density, LD) until they were moved to a grazing area at 128 LSUs/ha (high density, HD). Animals were implanted subcutaneously with a T, HR, and ACT bio-logger, which was programmed to record data at 5-min intervals. For each animal, cosinor rhythmometry (the study of circadian rhythms by fitting a sine wave to a time series) was applied to the data recorded over 5 days in LD and HD. Mean Midline Estimating Statistic of Rhythm (MESOR; the average value around which the variable oscillates), amplitude (difference between the peak and the mean value of a wave), and acrophase (timing of peak activity) were calculated and evaluated statistically. Differences between mean day and nighttime values, and mean LD and HD values were calculated. Cows presented cosinor curves that fit a 24-h rhythm (p < 0.001) in T, HR, and ACT at both densities. MESOR (T: 37.98 vs. 38.02°C; HR: 69.12 vs. 65.91 bpm; ACT: 49.39 vs. 40.41 mg, for LD and HD, respectively) and amplitude (T: 0.28 vs. 0.28°C; HR: 4.12 vs. 3.14 bpm; ACT: 18.14 vs. 11.28 mg, respectively) did not differ significantly between the two densities; however, significant (p < 0.05) differences between densities occurred in the acrophase of the three variables; specifically, the T acrophase was 2 h later at HD (22:45 h) than LD (20:45 h), and HR (LD: 19:51; HD: 16:49 h) and ACT acrophases 3 and 2 h earlier at HD than LD (LD: 14:47; HD: 12:49 h), respectively. T and ACT differed significantly (p < 0.01) between daytime (mean ± SE; 37.92 ± 0.19°C, 40.39 ± 4.74 mg) and nighttime (38.14 ± 0.17°C, 29.93 ± 5.66 mg). In conclusion, our study suggests that a high animal grazing density might exacerbate the social competence for valuable resources for animals, resulting in shifting the circadian rhythmicity of temperature, heart rate, and activity of the cows, advancing or delaying their acrophases.
000151182 540__ $$9info:eu-repo/semantics/openAccess$$aby$$uhttps://creativecommons.org/licenses/by/4.0/deed.es
000151182 590__ $$a4.755$$b2021
000151182 591__ $$aPHYSIOLOGY$$b20 / 81 = 0.247$$c2021$$dQ1$$eT1
000151182 592__ $$a1.126$$b2021
000151182 593__ $$aPhysiology (medical)$$c2021$$dQ1
000151182 593__ $$aPhysiology$$c2021$$dQ1
000151182 594__ $$a6.6$$b2021
000151182 655_4 $$ainfo:eu-repo/semantics/article$$vinfo:eu-repo/semantics/publishedVersion
000151182 700__ $$aPlaza J.
000151182 700__ $$0(orcid)0000-0003-2827-3054$$aAbecia J.-A.$$uUniversidad de Zaragoza
000151182 7102_ $$12008$$2700$$aUniversidad de Zaragoza$$bDpto. Produc.Animal Cienc.Ali.$$cÁrea Producción Animal
000151182 773__ $$g12 (2021), [9 pp.]$$pFront. physiol.$$tFrontiers in physiology$$x1664-042X
000151182 8564_ $$s2132673$$uhttps://zaguan.unizar.es/record/151182/files/texto_completo.pdf$$yVersión publicada
000151182 8564_ $$s2310785$$uhttps://zaguan.unizar.es/record/151182/files/texto_completo.jpg?subformat=icon$$xicon$$yVersión publicada
000151182 909CO $$ooai:zaguan.unizar.es:151182$$particulos$$pdriver
000151182 951__ $$a2025-10-17-14:17:51
000151182 980__ $$aARTICLE