Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Data Collection by Observations

Data Collection by Observations

Data collection refers to a systematic way of obtaining, observing, measuring, and analyzing accurate information. Observational studies are one of the most widely used methods of data collection. It involves collecting data by observing the behavior and physical characteristics of a sample without making any modifications to the sample.
An astronomer viewing the motion and brightness of stars in the sky and recording the data is an example of observational data collection. A botanist recording...

Drug Concentrations: Measurements

Drug Concentrations: Measurements

Drug concentration is the quantity of a drug present in a biological sample. Measuring drug amounts in biological samples allows the clinician to understand how a drug is absorbed, distributed, metabolized, and excreted. Samples can be obtained through invasive or non-invasive methods. Invasive techniques involve surgical or parenteral interventions to gather blood, cerebrospinal fluid, or tissue biopsy. Conversely, non-invasive approaches provide samples like urine, feces, and saliva.
Plasma —...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Demography and Environment Shapes Genetic Variation: Spatiotemporal Genetic Dynamics in Cyclic Voles at Low Latitudes.

Molecular ecology·2026

Same author

Escalated begging does not compromise nestling health.

Behavioral ecology : official journal of the International Society for Behavioral Ecology·2025

Same author

An immune challenge affects growth dynamics, oxidative stress and survival in wild spotless starling nestlings.

The Journal of experimental biology·2025

Same author

The Impairment of Body Condition Transiently Increases Oxidative Stress: A Dietary Restriction Experiment in Partridges.

Journal of experimental zoology. Part A, Ecological and integrative physiology·2025

Same author

Not all who wander are lost: prospecting and settlement of male floaters in the spotless starling.

Behavioral ecology : official journal of the International Society for Behavioral Ecology·2025

Same author

A LEAP Forward in Wildlife Conservation: A Standardized Framework to Determine Mortality Causes in Large GPS-Tagged Birds.

Ecology and evolution·2025

Search research articles

Related Experiment Video

Updated: Jul 17, 2026

Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer

Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer

Published on: January 29, 2020

Repeated sampling but not sampling hour affects plasma carotenoid levels.

Lorenzo Pérez-Rodríguez¹, Carlos Alonso-Alvarez, Javier Viñuela

¹Instituto de Investigacion en Recursos Cinegeticos (Consejo Superior de Investigaciones Cientificas, Universidad de Castilla-La Mancha, Junta de Comunidades de Castilla-La Mancha), Ronda de Toledo s/n 13071, Ciudad Real, Spain. lorenzo.perez@uclm.es

Physiological and Biochemical Zoology : PBZ

|January 26, 2007

Summary

Plasma carotenoid levels in red-legged partridges (Alectoris rufa) are not affected by the time of day. However, repeated blood sampling significantly reduces carotenoid concentrations due to hemodilution.

More Related Videos

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Published on: April 7, 2020

Related Experiment Videos

Last Updated: Jul 17, 2026

Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer

Measurement of Carotenoids in Perifovea using the Macular Pigment Reflectometer

Published on: January 29, 2020

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Human Circadian Phenotyping and Diurnal Performance Testing in the Real World

Published on: April 7, 2020

Area of Science:

Animal signaling and coloration
Avian physiology and endocrinology
Biochemical analysis in wildlife

Background:

Carotenoid pigments are crucial for animal signaling, making plasma carotenoid level measurement common in research.
Plasma biochemical parameters often vary with sampling time, potentially introducing error.
The diurnal variation of circulating carotenoids is not well understood.

Purpose of the Study:

To investigate the influence of sampling hour and repeated blood extraction on plasma carotenoid concentration.
To assess potential sources of error in carotenoid measurements in red-legged partridges (Alectoris rufa).

Main Methods:

A specific sampling protocol was designed to differentiate the effects of sampling time and repeated blood draws.
Plasma carotenoid concentrations and hematocrit values were measured in captive red-legged partridges.
Within-individual analyses were performed to evaluate parameter effects.

Main Results:

Sampling hour did not significantly affect plasma carotenoid variability.
Carotenoid levels significantly decreased with repeated blood sampling, evident from the second sample.
Carotenoid variability correlated positively with hematocrit, which also decreased during repeated sampling.

Conclusions:

Blood sampling time does not pose a significant risk of adding variance to carotenoid data in this species.
Repeated blood sampling can lead to hemodilution, significantly impacting carotenoid levels.
Researchers should account for potential hemodilution effects in studies involving serial blood sampling for carotenoid analysis.