35 research outputs found
Descriptive Statistics.
<p>Descriptive statistics for hormone data for bottlenose dolphins sampled in Sarasota Bay, FL (2000–2012). Abbreviations: N<sub>i</sub> = number of individuals; “% BDL” indicates the percentage of observations with hormone concentrations below respective detection limits.</p><p>*Values below detection limit calculated as ½ of the detection limit for the assay (Schwacke et al. 2009)</p><p><sup>+</sup>Detection Limits: cortisol (0.2 μg/dL); aldosterone (11 pg/mL)</p><p>Descriptive Statistics.</p
Serum Cortisol Reference Intervals.
<p>Serum cortisol (ÎĽg/dL) 95<sup>th</sup> percentile reference intervals and associated 90% confidence intervals for free-ranging bottlenose dolphins sampled in less than 30 minutes following net deployment (pre-sampling) and dolphins sampled following veterinary procedures (post-sampling).</p><p>Serum Cortisol Reference Intervals.</p
Linear Mixed Models.
<p>Linear mixed model (LMM) results for covariates significantly associated with bottlenose dolphin serum concentrations of cortisol and aldosterone. Parameters in bold were significantly associated with cortisol concentrations (p<0.05). Abbreviations: N<sub>o</sub> = number of observations; N<sub>i</sub> = number of individuals; F = F statistic; df = numerator, denominator degrees of freedom.</p><p>^Log-transformed</p><p>Linear Mixed Models.</p
Aldosterone Plots.
<p>(a) Pre-sampling aldosterone concentration (pg/mL) versus elapsed sampling time (min) and (b) pre-sampling aldosterone concentration (pg/mL) versus pre-sampling cortisol concentration (μg/dL) for bottlenose dolphins sampled in Sarasota Bay, FL 2000–2012 <i>(N = 103)</i>. Correlation coefficient (r) and statistical significance (p) reported for Spearman’s correlation test.</p
Cortisol Reference Intervals.
<p>(a) Pre-sampling (<30 minutes elapsed time) and (b) post-sampling 95<sup>th</sup> percentile reference intervals for serum cortisol (μg/dL) versus elapsed sampling time (min). Points represent measured pre-sampling <i>(N = 93)</i> and post-sampling <i>(N = 52)</i> serum cortisol values for bottlenose dolphins sampled in Sarasota Bay, FL 2000–2012; solid lines represent upper and lower bounds for the 95<sup>th</sup> percentile.</p
Pre-Sampling Cortisol versus Elapsed Sampling Time.
<p>Pre-sampling cortisol concentration (μg/dL) vs. elapsed sampling time (min) for bottlenose dolphins sampled in Sarasota Bay, FL 2000–2012 <i>(N = 118)</i>.</p
Adrenal Hormones in Common Bottlenose Dolphins (<i>Tursiops truncatus</i>): Influential Factors and Reference Intervals
<div><p>Inshore common bottlenose dolphins (<i>Tursiops truncatus</i>) are exposed to a broad spectrum of natural and anthropogenic stressors. In response to these stressors, the mammalian adrenal gland releases hormones such as cortisol and aldosterone to maintain physiological and biochemical homeostasis. Consequently, adrenal gland dysfunction results in disruption of hormone secretion and an inappropriate stress response. Our objective herein was to develop diagnostic reference intervals (RIs) for adrenal hormones commonly associated with the stress response (i.e., cortisol, aldosterone) that account for the influence of intrinsic (e.g., age, sex) and extrinsic (e.g., time) factors. Ultimately, these reference intervals will be used to gauge an individual’s response to chase-capture stress and could indicate adrenal abnormalities. Linear mixed models (LMMs) were used to evaluate demographic and sampling factors contributing to differences in serum cortisol and aldosterone concentrations among bottlenose dolphins sampled in Sarasota Bay, Florida, USA (2000–2012). Serum cortisol concentrations were significantly associated with elapsed time from initial stimulation to sample collection (p<0.05), and RIs were constructed using nonparametric methods based on elapsed sampling time for dolphins sampled in less than 30 minutes following net deployment (95% RI: 0.91–4.21 µg/dL) and following biological sampling aboard a research vessel (95% RI: 2.32–6.68 µg/dL). To examine the applicability of the pre-sampling cortisol RI across multiple estuarine stocks, data from three additional southeast U.S. sites were compared, revealing that all of the dolphins sampled from the other sites (N = 34) had cortisol concentrations within the 95th percentile RI. Significant associations between serum concentrations of aldosterone and variables reported in previous studies (i.e., age, elapsed sampling time) were not observed in the current project (p<0.05). Also, approximately 16% of Sarasota Bay bottlenose dolphin aldosterone concentrations were below the assay’s detection limit (11 pg/mL), thus hindering the ability to derive 95th percentile RIs. Serum aldosterone concentrations from animals sampled at the three additional sites were compared to the detection limit, and the proportion of animals with low aldosterone concentrations was not significantly different than an expected prevalence of 16%. Although this study relied upon long-term, free-ranging bottlenose dolphin health data from a single site, the objective RIs can be used for future evaluation of adrenal function among individuals sampled during capture-release health assessments.</p></div
Overall common bottlenose dolphin abundance and density estimates by stratum in Mississippi Sound from the spatially-explicit robust-design capture-recapture model applied to 2010–2012 photo-identification data.
<p>Overall common bottlenose dolphin abundance and density estimates by stratum in Mississippi Sound from the spatially-explicit robust-design capture-recapture model applied to 2010–2012 photo-identification data.</p
Monthly 2013 Getis-Ord Gi* (“hotspots”) of the inshore common bottlenose dolphins tagged with satellite-linked transmitters in Mississippi Sound.
<p>Monthly 2013 Getis-Ord Gi* (“hotspots”) of the inshore common bottlenose dolphins tagged with satellite-linked transmitters in Mississippi Sound.</p
Number of marked common bottlenose dolphin individuals from each site fidelity bin observed during photo-identification surveys in Mississippi Sound during 2010–2012 (Low = 1–2 primary periods; moderate = 3–4 primary periods; high = ≥ 5 primary periods).
<p>Number of marked common bottlenose dolphin individuals from each site fidelity bin observed during photo-identification surveys in Mississippi Sound during 2010–2012 (Low = 1–2 primary periods; moderate = 3–4 primary periods; high = ≥ 5 primary periods).</p