Search Results (100)

Hair-based biomarkers offer a non-invasive window into chronic stress physiology, yet the influence of sampling body site on hair cortisol, dehydroepiandrosterone (DHEA), and their molar ratio has not been systematically characterized in domestic dogs. This study compared these three biomarkers across three anatomical sites—shoulder (mid-scapula), neck (dorsal midline), and rump (sacroiliac region)—in 30 neutered Anatolian shelter dogs (2–3 years; 15 males, 15 females; 30 dogs total, with each dog sampled at all three body sites) housed in individual kennels over eight weeks. Hair samples were collected at week 0 and week 8, extracted by methanol pulverization, and quantified by validated ELISA protocols. Hair cortisol differed significantly by site (p < 0.001), as did DHEA (p < 0.01) and cortisol-to-DHEA ratios (p < 0.001). Cortisol decreased modestly over eight weeks (p < 0.05). DHEA was inversely correlated with cortisol (r = −0.62, p < 0.01). The shoulder site yielded the highest absolute concentrations and the greatest cortisol-to-DHEA ratio, combined with the lowest within-site coefficient of variation (CV = 11.2% vs. 13.8% at neck and 15.6% at rump), jointly supporting its designation as the preferred anatomical sampling location. The cortisol-to-DHEA ratio is identified as a nuanced welfare indicator that integrates both allostatic load and adaptive resilience capacity, with implications for standardized non-invasive stress assessment protocols in shelter medicine. Full article

Hair is an easily obtainable, non-invasive biomatrix that allows for the assessment of long-term physiological responses to environmental and anthropogenic stressors in wildlife populations. Herein, an ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UHPLC-ESI-MS/MS) method was validated to verify its suitability for the simultaneous determination of cortisol (CORT) and its metabolite, cortisone (CORN), in hair samples collected from wild-living grey wolves (Canis lupus). Hair samples were extracted with methanol and purified using solid-phase extraction on Strata-X cartridges, which enabled effective mitigation of matrix effects. Data for the glucocorticoids were normalized using internal standards. The method demonstrated good linearity for the target stress hormones, with satisfactory precision (RSD < 15%) and limits of quantification of 4.13 pg/mg for CORT and 2.49 pg/mg for CORN in the hair matrix. Analysis of authentic wolf hair samples revealed CORT and CORN concentrations in the ranges of <4.13–11.86 pg/mg and <2.49–3.67 pg/mg, respectively. The CORT results showed a strong positive correlation with those obtained using enzymatic immunoassays. The method may be applied to assess the impact of stressors on the welfare of wolves, e.g., providing a useful tool for monitoring recovering European populations as they face new challenges associated with expansion into potentially suboptimal habitats. Full article

Background: Exposure of pregnant women to stress and endocrine-disrupting chemicals (EDCs) during pregnancy can have a substantial impact on mother and infant health. We investigated the concentrations of EDCs, such as parabens (PBs) and triclosan (TCS), as well as stress hormones (cortisone and cortisol), across pregnancy trimesters and examined their associations with maternal average telomere length (TL). Methods: Hair samples from 49 postpartum women were analyzed using liquid chromatography–mass spectrometry (LC-MS) to quantify EDCs and stress hormone concentrations. Results: The mean methyl paraben concentrations in the hair of postpartum women were prevalent across all pregnancy trimesters, while butyl paraben was detected at the lowest levels. The mean concentration of PBs followed the order methyl > propyl > ethyl > benzyl > butyl paraben across pregnancy trimesters. We found that ethyl paraben and triclosan were each positively and significantly associated with cortisol levels in postpartum women’s hair. Consistent with this, the mean cortisone concentration gradually increased from the first to the third pregnancy trimester, whereas cortisol reached the highest mean concentration at the second trimester. A significant positive association between cortisol and cortisone levels was observed. Further analyses revealed that mothers’ average TL was positively associated with ethylparaben and triclosan levels and inversely associated with benzylparaben levels. Last but not least, we found that cortisol/cortisone levels were positively associated with postpartum women’s TL in a statistically significant manner. Conclusions: In the present study, prenatal exposure to stress hormones and EDCs appears to exert a statistically significant impact on maternal TL dynamics. Full article

Background/Objectives: Work stress (WS), occupational fatigue (OF), and Burnout syndrome (BS) among administrative workers are associated with negative psychosocial and metabolic effects. Although antioxidant-rich nutritional strategies have been proposed to help manage stress, evidence from real-world occupational settings is still limited. This study evaluated the total antioxidant capacity (TAC) of a multi-antioxidant dietary supplement 2.0 (DS2.0; apple polyphenols, [APP], astaxanthin [AXT], and fucoxanthin [FXT]; 387:12:1 ratio) and explored its association with metabolic parameters, OF, psychosocial outcomes, and hair cortisol concentration (HCC) in administrative workers with and without obesity. Methods: A quasi-experimental pilot study was conducted among 22 workers, who received DS2.0 (52.13 mg/day, n = 17) or a placebo (n = 5) for 30 days. TAC was analytically assessed using standardized assays. Metabolic outcomes (lipid profile, fasting plasma glucose), psychosocial variables (SOFI-SM, CESQT/SBI, and IMSS tests), and HCC (competitive immunoassay) were evaluated before and after supplementation. Statistical analyses included within-group pre–post comparisons, independent-sample tests, and effect size estimation. Results: DS2.0 demonstrated high TAC. Supplementation was associated with reductions in total lipids, total cholesterol, and non-HDL cholesterol, as well as decreases in OF, BS, and WS scores. HCC decreased in the overall sample (217.19 vs. 31.64 pg/mg; p = 0.000) and among workers with obesity (276.80 vs. 34.13 pg/mg; p = 0.002). Stress-related symptoms, including sleep deprivation, exhaustion, appetite changes, difficulty waking, and palpitations, also improved (p ≤ 0.05). Conclusions: An antioxidant-rich DS2.0 supplement may be associated with psychosocial and stress-related biomarkers; however, these exploratory findings require confirmation in larger randomized controlled trials. Trial registration: ISRCTN 12762846. Full article

Tobacco smoke exposure not only increases the risks of lung cancer and cardiovascular disease, but can be a stressor contributing to mental illness. It is important to clarify the relationship between chronic tobacco smoke exposure and mental stress from the perspective of disease prevention. We developed a simple and highly sensitive method for simultaneously analyzing nine biomarkers: nicotine and cotinine (tobacco smoke exposure markers); cortisol, testosterone, and dehydroepiandrosterone (stress-related markers); and serotonin, melatonin, dopamine, and oxytocin (relaxation-related markers). Biomarkers were extracted and concentrated by in-tube solid-phase microextraction with a Supel-Q PLOT capillary, followed by separation and detection within 7 min using liquid chromatography–tandem mass spectrometry on a Discovery HS F5 column. Calibration curves using stable isotope-labeled internal standards showed good linearity (0.005–100 ng mL⁻¹) with detection limits of 0.09–13.5 pg mL⁻¹. Intra-day and inter-day precision had relative standard deviations below 7.2% and 15.5% (n = 6), respectively, with recovery rates of 84.0–108.8%. The automated method requires only ultrafiltration of hair methanol extract, enabling non-invasive pg-level analysis using just a few milligrams of hair. Hair analysis reflects an association between chronic tobacco smoke exposure and stress. This method is effective for analyzing the relationship between long-term tobacco smoke exposure and chronic stress. Full article

Tongue-rolling behavior (TR) is commonly observed in dairy cows and is considered a stereotypic behavior indicative of compromised welfare. Chronic stress can impair lactation and immune function, yet the interaction between behavior (TR vs. normal behavior (NB)) and chronic stress (high vs. low) remains unclear. In this study, hair cortisol concentration (HCC) was used to assess stress levels in cows. The cows were first classified into high- and low-stress cows using K-means clustering. Subsequently, cows exhibiting high levels of TR and those exhibiting NB (i.e., no stereotypic behaviors) were selected from both stress categories to establish four groups (n = 8 per group): high-stress TR (HT), high-stress NB (HN), low-stress TR (LT), and low-stress NB (LN). We analyzed milk protein composition, milk proteome, and plasma immune-inflammatory indicators. Behavior (TR vs. NB) and chronic stress (high vs. low) showed significant interaction effects on plasma tumor necrosis factor-α (p = 0.046), interleukin-6 (p = 0.002), and proteomic profiles, involving multiple guanosine triphosphate-binding proteins (p < 0.05), transferrin (p = 0.001), and complement factors (p < 0.05). In addition, TR cows had significantly lower levels of αs1-casein (p = 0.019), β-casein (p < 0.001), κ-casein (p = 0.016), lactoferrin (p = 0.003), and plasma immunoglobulin A (p = 0.002). These results indicate that, under different chronic stress levels, TR cows differ markedly from NB cows in milk protein expression, immune function, and inflammatory responses. Moreover, milk from TR cows showed reduced quality, and immune dysfunction and inflammation were exacerbated under high stress. Overall, this study provides new insights into the physiological consequences of stereotypic behavior in dairy cows. These findings may help dairy farmers identify cows exhibiting TR as at risk of reduced milk quality and immune dysfunction, allowing for early management interventions to improve animal welfare and productivity. Full article

Dog-assisted interventions (DAIs) are an established procedure to support military staff, but their implementation during active warfare has not yet been systematically studied. In addition, the welfare of therapy dogs participating in DAIs during war remains unexplored. Therapy dogs may develop clinically relevant emotional disorders, including trauma-related stress responses, analogous to human psychopathologies. The present study sought to monitor physiological arousal in therapy dogs performing DAI sessions with their handlers in two Ukrainian military hospitals (Vinnyzja and Kyiv). Biomarkers of hypothalamic–pituitary–adrenal (HPA) axis activity, including salivary, urinary, and hair cortisol concentrations, were assessed in Ukrainian (UA) therapy dogs to capture their acute and long-term stress responses. Additionally, cortisol levels in German (GE) therapy dogs performing similar DAIs under peaceful conditions were measured to compare cortisol levels between dogs from both regions. Results suggest that GE therapy dogs exhibited significantly higher urinary concentrations, reflecting alterations in longer-term glucocorticoid secretion that is possibly caused by war-related stimulation in the UA cohort. In contrast, no significant differences in salivary cortisol emerged as a consequence of performing DAIs. The present findings suggest that the environment rather than involvement in DAIs has an impact on therapy dogs’ cortisol secretion. Full article

Gastrointestinal nematodes (GIN) represent a major constraint to sheep production, and sustainable alternatives to routine anthelmintic use are increasingly required. This study compared two parasite control strategies in Zerasca sheep: routine albendazole treatment administered twice yearly (T) and a long-term non-chemical approach based on rotational grazing (relocation to a new pasture when grass height fell below 10 cm) combined with quarterly veterinary monitoring (NT). Twenty-four adult ewes (n = 12 per group) were monitored over an eight-month period. Mean faecal egg counts (EPG) differed significantly between groups (T: 210 ± 78; NT: 529 ± 89; p = 0.0007). In group T, EPG values decreased markedly 7 days after treatment but increased again by 150 days, resulting in no persistent differences between groups over time. Despite higher parasite burdens, NT sheep showed significantly higher body condition scores compared with treated animals (3.00 ± 0.61 vs. 2.51 ± 0.53; p = 0.0014). Haematological parameters were largely comparable between groups, although mild reductions in RBC, HGB, and HCT were observed in both. Treated sheep exhibited higher AST activity (p < 0.0001) and transient increases in ALT and BUN following treatment. Hair cortisol concentrations did not differ significantly between groups. Overall, these findings suggest that a non-chemical parasite management strategy, when combined with controlled grazing and veterinary monitoring, may maintain acceptable parasite levels while supporting body condition and stable welfare indicators, potentially reducing reliance on routine anthelmintic treatments. Full article

Although sample matrices are available for assessing cortisol output over hours/days (serum, saliva, or urine) or months (hair or nails), there is no current method for measuring integrated cortisol output over a period of 1 week. Therefore, the primary aim of this study was to develop and validate a method for collecting and measuring sweat-derived cortisol from commercially available skin patches worn for 1 week. Additional aims were to determine whether the accumulated sweat cortisol correlated with salivary cortisol measured during the same week, and whether sweat cortisol was related to psychological stress measured using two different questionnaires. After conducting preliminary in vitro validation studies, we obtained the following data from a convenience sample of university students and employees: (a) cortisol and sodium contents of patches worn for 1 week (sodium was used to correct for variation in sweating rate), (b) mean area-under-the-curve of salivary cortisol concentrations measured for 3 days during the week of patch wearing, and (c) two different measures of psychological stress. The results demonstrate that a continuously worn sweat patch can be used to collect and measure sweat cortisol over a 1-week period. However, the patch’s cortisol contents did not correlate with either the salivary cortisol area under the curve or the participants’ psychological stress. Because previous findings showed that sweat cortisol is significantly related to both circulating and salivary cortisol levels, we hypothesize that the lack of an observed correlation between patch and salivary cortisol may have resulted from limitations of our experimental design. Full article

Our aim was to compare certain physiological traits and pregnancy rates in dairy heifers classified by coat color during summer and winter months in a Sonoran Desert region. Sixty Holstein heifers were randomly selected (age and weight of 13.1 ± 0.82 months and 382 ± 5.3 kg) and divided by season (i.e., winter and summer) and hair coat color (i.e., black and white). There were 28 summer heifers (13 black/15 white) and 32 in winter (18 black/14 white). Respiratory frequency (RF) was determined visually, and body surface temperatures (BSTs) of several anatomic regions were collected using thermography at 06:00 and 15:00 h every 3rd day. Furthermore, three blood samples were collected from each heifer in each season to determine hematological profiles and serum analytes (i.e., electrolytes, metabolites, hormones). Reproductive variables were pregnancy rate and services per pregnancy. Ambient temperatures ranged from 25 to 49 °C in summer and 3 to 28 °C in winter. In summer and winter, RF and most BST were higher (p < 0.05) in black heifers in the morning, while only head, right flank, and loin were higher (p < 0.05) in the afternoon. Cortisol and progesterone concentrations were higher (p < 0.01) in summer, while thyroid hormones were higher (p < 0.05) in winter. Glucose, triglycerides, cholesterol, urea, and sodium were higher (p < 0.05) in winter. Reproductive traits were unaffected by season or coat color. Although there were some differences in physiological variables and some biochemical parameters by season and coat color, these alterations were not enough to modify reproductive responses of Holstein heifers. Full article

Background: Cortisol is known as the main hormone released during stress responses in cattle and has been used to assess various stressors, including heat stress. This study investigated hair cortisol concentration (HCC) in different hair coat colors in dairy cows under natural heat stress conditions (temperature humidity index = 75). Methods: Hair samples were collected from the forehead region of ten multiparous cows (Brown Swiss, Montbéliarde, and Holstein) per group color at both the beginning and end of a three-week peak summer period in 2024 in the region of Jendouba, North Tunisia. Cows were grouped according to hair coat color (black, brown, red, white, and yellow) for subsequent analysis. Hair samples were prepared using a methanol-based separation protocol and analyzed via enzyme-linked immunosorbent assay (ELISA). Results: Meteorological data confirmed that cows were sustained under heat stress, with an average temperature humidity index value of 75; results indicated that black hair had considerably more HCC than white hair (p < 0.05). The results showed that there is a significant difference between HCC under three clusters (p < 0.05) according to hair color. Conclusions: The study emphasizes that hair color, along with factors such as breed and environmental conditions, should be carefully considered when using HCC to assess stress in cattle beyond simply black or white hair color. Full article

An unhealthy prepubertal diet can have long-lasting effects throughout life. This study investigated hair concentrations of adrenal and sex steroids, in an in vivo mouse model of juvenile obesity subjected to control (CTRL), obesogenic (HFHC) diet, or nutraceutical supplementation (silymarin or coconut oil) diets. 87 3-week-old C57BL/6 mice (42 females, 45 males) were fed CTRL or HFHC diets for 8 weeks. Afterward, the CTRL group continued on CTRL diet while the HFHC diet group was divided into five groups: HFHC, HFHC→CTRL, HFHC→CTRL + silymarin (SIL), HFHC→HFHC + SIL and HFHC→HFHC + Coconut oil. At 4 weeks, the HFHC group showed increased cortisol/dehydroepiandrosterone (DHEA) ratio compared to CTRL group. At 20 weeks, the HFHC→HFHC group showed higher levels of progesterone (P4) and dehydroepiandrosterone sulfate (DHEA-S) and lower levels of estradiol (E2) compared to the CTRL→CTRL group. The switch from HFHC→CTRL was the optimal therapy because the body weight and almost all the hormones were close to those observed for the CTRL diet group. Supplement with SIL or Coconut oil reduced DHEA-S and increased in E2 compared with the endocrine setting seen with the HFHC diet. These interventions should be considered as supportive measures rather than substitutes for dietary correction. Full article

Background: Adverse childhood experiences (ACEs) can lead to hypothalamic–pituitary–adrenal axis dysregulation, negatively impacting child growth and development. Methods: The Hair Biomarkers Study (HBS-I) evaluated healthy preschool children using parent-reported surveys, anthropometrics, and painlessly obtained scalp hair to measure hair cortisol (HCC; ng/mg) and oxytocin concentrations (HOC; ng/mg) via ELISA; log-transformed data were used in analyses. Height, weight, and BMI percentiles were based on CDC growth curves. Linear regressions examined associations of child and maternal hair biomarkers with percentiles, adjusting for sociodemographic factors. Results: The median age was 39.1 months (IQR 23.5–53.0, N = 1189). Higher child Ln-HCC was associated with an increased BMI percentile (0.027; 95%Cl: 0.013, 0.040), while higher child Ln-HOC was associated with a decreased BMI (−0.016; 95%Cl: −0.028, −0.005). Similar significant associations were observed between maternal biomarkers and child growth. In models mutually adjusted for mother and child hair biomarkers, maternal Ln-HCC was associated with an increased BMI percentile (0.036; 95%Cl: 0.003, 0.069), while maternal Ln-HOC was associated with a decreased BMI percentile (−0.034; 95%Cl: −0.052, −0.016). Maternal ACEs of 2–3 vs. 0–1 were associated with increased child weight (0.057; 95%Cl: 0.003, 0.112) and BMI percentiles (0.076; 95%Cl: 0.017, 0.135). Conclusions: We show that higher maternal and child HCC was associated with increased child BMI percentiles, while higher HOC was linked with decreased BMI percentiles. Hair biomarkers may reflect the effects of nurturing vs. adverse experiences during critical windows of growth and development in early childhood. Full article

The Nero di Lomellina (NL) pig, a newly established breed from the cross of the Poland China with the Berkshire breed, which was created to reconstitute a local breed called Nero di Cavour, was recognized by the Italian Ministry of Agriculture in 2020 (DM 12222/2020). The objective of this study is to investigate, for the first time, the zootechnical performance and environmental response of the NL breed in comparison with a commercial crossbreed (CH; Large White × Duroc). An evaluation was conducted of a traditional closed-cycle farming system rearing NL and CH mixed in the same units. Pigs were observed for two cycles of 10 months each, one with piglets born in winter and the other in summer, to evaluate the productive performance and stress response through hair cortisol (HCC) levels of the pigs according to environmental conditions. For this purpose, the temperature–humidity index (THI) was calculated for each phase of the two cycles, and the values were compared with the comfort zone values indicated by the Italian Classyfarm values. The NL pigs showed slower growth performance in the first phase, with a high THI (p < 0.05). In the R2 phase, the backfat thickness was higher in the NL than CH pigs (p < 0.001). The CH had consistently higher HCC compared with the NL pigs across the production phases, showing a potential higher response to chronic stress. It is worth noting that the NL weaners and growers seemed to better face a cold environment, referring to their growth performance in comparison with the commercial breed, although the local breeds usually show a slower growth rate and hair cortisol levels during the second cycle, which was characterized by prolonged low temperatures far from the comfort zones. More studies are needed to deepen the influence of the environment, as well as consider the outdoor conditions on the physiological status, productivity, and meat quality of this new breed. Full article

Background: Over the last 30 years, stress and anxiety in children have risen exponentially, especially as a result of school expectations. As no studies have examined the effect of increased outdoor recess on children’s chronic stress levels, this preliminary work focused on comparing hair cortisol concentration (HCC) scores of elementary children who received varied amounts of daily recess. Methods: HCC scores were collected from 4th grade elementary children (N = 130) from three intervention schools (45 min daily recess) (N = 64; M = 35; F = 29) and three control schools (30 min daily recess) (N = 66; M = 31; F = 35). Results: A two-way ANOVA, F(1, 123) = 5.47, p = 0.021, ω² = 0.034, showed that the intervention group reflected lower HCC levels (marginal M = 5.69, 95% CI [−1.92, 13.30]) than the control group (marginal M = 18.22, 95% CI [10.83, 25.61]). Post hoc analysis revealed an estimated marginal mean difference of −12.53 (SE = 5.36, p = 0.021). Sample t-tests compared HCC levels against the pre-COVID normative value of 7.5 pg/mg. The intervention group HCC mean (M = 5.85, SD = 6.26) was significantly lower than the normative value, t(61) = −2.08, p = 0.042. The control group’s mean HCC (M = 18.22, SD = 41.39) was significantly higher than the normative value, t(64) = 2.09, p = 0.041. Conclusions: Increasing daily recess may contribute to lower chronic stress levels among 4th grade children. With obesity and mental health disorders on the rise and American students’ academic performance on the decline, these pilot results cannot be overlooked or dismissed. Full article