Alberto Prandi

Shelter dogs may experience long-term environmental and social stressors that can affect their behaviour and welfare. Some individuals show reduced activity, low responsiveness to environmental stimuli, and limited interaction with their surroundings. This pilot study investigated behavioural patterns and allopregnanolone concentrations in shelter dogs exhibiting these behavioural characteristics. Ten shelter dogs were enrolled and divided into two groups: five dogs showing depression-like patterns and five matched control dogs. Each dog wore a three-axis accelerometer for 30 days to quantify activity levels. Behavioural observations were conducted using video recordings, and hair samples were collected at baseline and after 30 days to assess allopregnanolone concentrations as a potential stress marker. Dogs in the case group showed significantly longer resting time than controls (p ≤ 0.05), indicating reduced activity levels. Trends toward lower levels of exploratory and social behaviours were also observed, although the differences were not statistically significant. Allopregnanolone concentrations ranged from 0.6 to 4.6 pg/mg and showed considerable inter-individual variability, with no significant differences detected between groups. These findings provide preliminary evidence of behavioural and physiological alterations in shelter dogs displaying depression-like patterns. However, further studies with larger populations are needed to validate these findings and improve welfare assessment in shelter environments.

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.

Besides metabolic and cardiovascular parameters, fluctuations in endocrine and inflammatory biomarkers might be regarded as reliable indicators of allostatic load. Among them, glucocorticoids have been shown to correlate with social stress in animals, regardless of whether they are dominant or subordinate, thus highlighting the crucial role of physiological energetic costs, together with social challenges, in the onset and severity of allostasis. Therefore, in the present work, we evaluated and monitored monthly the concentration of cortisol in bristles (pg/mg) over six months in young (n = 8), sub-adult (n = 5) and adult female wild boars (n = 5), which were kept in a controlled State Forest in Southern Italy. Our data revealed higher concentrations of cortisol in young animals when compared to sub-adult (p < 0.01) and adult (p < 0.05) groups. Moreover, such an increase faded away over time, and cortisol concentrations were found to be overlapping those of sub-adult and adult groups, which did not display any significant variation throughout monitoring. Collectively, our findings suggest that the wild boars adapted to the controlled environment, thus preserving both a physiological state and animal welfare.

Poor health and increased susceptibility to infectious diseases are among the main sources of economic losses in the pig industry worldwide, and they also serve as indicators of compromised animal welfare. However, there is limited information on long-lasting biomarkers of poor health and common infections experienced by piglets early in life. Hair cortisol, dehydroepiandrosterone sulfate (DHEA(S)), and their ratio have been proposed as components of the mammalian stress response due to the activation of the hypothalamus–pituitary–adrenal axis and were investigated in this study using 30 batches of pigs from 16 farms. The research hypothesis was that batches of piglets experiencing clinical syndromes (as indicated by enteric, neurological, cutaneous, and locomotor scores) during suckling would exhibit a different pattern of resilience and allostatic load later in life compared to healthy ones. Hair from 25 gilts per batch were collected at either 3.5 or 9 months of age, and hormone extraction was subsequently performed. The farm of origin and the age of the animals significantly influenced hormone concentrations. Moreover, batches affected by enteric disease showed lower DHEA(S) levels (p < 0.0001; 15.89 vs. 23.51 pg/mg) and higher cortisol/DHEA(S) ratio (p < 0.0001; 82.83 vs. 55.02) than healthy batches. Similar results were observed in batches with a neurological syndrome (DHEA(S): p < 0.0001; 12.91 vs. 19.43; cortisol/DHEA(S) ratio: p < 0.0001; 97.15 vs. 70.26 pg/mg). These results suggest that pig hair biomarkers carry an intrinsic and temporally stable signal related to early life health status.

Assay of steroid hormones in hair has become an attractive alternative for studies focusing on the perinatal period in equine medicine. The aim of the present study was to evaluate mares’ and foals’ hair ALLO concentrations and their ratio in relation to clinical conditions and selected clinical parameters. The 37 mare–foal pairs were categorized into healthy (group H; n = 15) and sick (group S; n = 22) groups. ALLO from hair was measured using a commercial ELISA kit. Foal ALLO and foal/mare ALLO ratio were lower in group S compared to group H (p < 0.001). Moderate positive correlations were found between both the foal ALLO and foal/mare ALLO ratio and the mare’s gestation length (p = 0.003; r = 0.476 and p = 0.002; r = 0.487), between the foal ALLO and foal’s weight (p = 0.042; r = 0.336), and between the foal/mare ALLO ratio and foal’s Apgar score (p = 0.047; r = 0.410). Based on a logistic regression model, a strong relationship (R² = 0.75) emerged between ALLO concentrations and foals’ clinical outcome, with concentrations of the hormone predicting foals’ clinical outcome with high accuracy (86.8%). Decreased foal ALLO and foal/mare ALLO ratio in sick foals appear to be potential biomarkers of prenatal disease toward the end of pregnancy.

Cortisol and DHEA(S) are markers of allostatic load and resilience; as such, they may be added to the definition of performance measures alongside immunocompetence. We aimed at studying the potential carryover effects of management practices on growth performances and the interrelationship between the hypothalamic–pituitary–adrenal (HPA) axis, immunocompetence and performances during the preweaning period in dairy calves. This study consisted of first a retrospective cohort study and second a prospective study. Calves had their growth performances and disease occurrence recorded, and their hair steroids (T1 at 20.03 ± 0.39 and T2 at 50.83 ± 0.41 days from birth) and plasmatic and colostral immunoglobulin G (IgG) was measured by immunoassays. The occurrence of preweaning diseases and the duration of individual housing negatively correlated to body weight (BW) at 60 days and the hair cortisol-to-DHEA(S) ratio (HC/HDHEA(S)) (T2) was negatively correlated to the daily weight gain (DWG) (−0.36; p < 0.05), plasmatic IgG (plaIgG) and the apparent efficiency of absorption (AEA) (−0.41; p < 0.01). Our results confirmed that the occurrence of diseases during the preweaning period and individual housing duration are pivotal for calves’ growth. This prospective study highlighted a detrimental effect of allostatic load on immunocompetence and described a link between resilience and growth performances.

Background: Unlike psychological distress, which has been extensively studied during the COVID-19 pandemic, the impact of the pandemic on stress hormones has been overlooked. The aim of this study is to examine the hair cortisol/dehydroepiandrosterone sulfate (DHEA-S) ratios as markers of HPA axis dysregulation in healthcare workers and their patients. Methods: A total of 200 healthcare workers and 161 “patients” patients with special healthcare needs due to chronic illness or motor disabilities were included in this study. The hormone concentrations were measured using a radioimmunoassay. Results: Our results show that the patients had significantly higher cortisol/DHEA-S ratios than the workers. A high cortisol/DHEA-S ratio in the patients reflects higher cortisol concentrations (p < 0.001) and lower DHEA-S (p < 0.05) concentrations compared to those of the healthcare workers, suggesting that they may be exposed to a greater degree of stress and a decrease in their ability to cope with their disease. The cut-off value of the hair cortisol/DHEA-S ratio in our study for detecting people with needs that require special consideration and attention was 1.46 (p ≤ 0.01). Conclusions: Assessing the hair cortisol/DHEA-S ratios in both healthcare workers and the patients allowed us to identify a non-homeostatic condition that could lead to disease and to understand psychophysical well-being during the COVID-19 pandemic. They also play a crucial role in preventive and personalized medicine.

Studies about puberty in dogs are few, probably because many factors are involved in the delicate process of puberty onset, leading to difficulties in the proper enrollment of subjects. Moreover, the use of blood for monitoring hormonal changes can be problematic, and not feasible for long-term studies. Hair and nails proved to be suitable matrices for the retrospective evaluation of hormones’ long-term accumulation. This study was performed using hair and nails for the evaluation of testosterone (T), 17β-estradiol (E2) and progesterone (P4) concentrations to assess possible sexual steroid changes during the peripubertal period in dogs. The results, obtained on five males and five females, showed a significant increase in T in hair and nails of males immediately before puberty. In females, a significant increase in E2 at puberty and a marked increase in P4 after puberty was found in both biological specimens. Sex-related differences were detected only for T hair concentrations, but when the sex and sampling time were considered together, hair and nails T and nails P4 concentrations allowed us to discern between male and female dogs at specific sampling times. The results from this study showed that hair and nails are useful biological specimens for the retrospective evaluation of changes in T, E2 and P4 concentrations in peripubertal dogs.

Testicular ultrasonography and steroid concentrations (cortisol, dehydroepiandrosterone sulfate (DHEA-S), cortisol/DHEA-S ratio, testosterone) in hair were examined for their utility in the bull breeding soundness evaluation (BBSE). Beef and dairy bulls (n = 16; 2.7 ± 0.4 years old; body condition score 3.2 ± 0.1) of five breeds were maintained under the same conditions at an accredited semen collection center. Bulls underwent routine semen collection twice weekly for 12 weeks and semen was processed and cryopreserved. Ultrasonography and hair sampling were undertaken at the last semen collection. Bulls with homogeneous testicular parenchyma (n = 8) had a higher (p < 0.05) percentage of motile sperm post-thawing compared with bulls with heterogeneous parenchyma (n = 8). There were no differences (p > 0.05) in the hair concentrations of cortisol, DHEA-S, and testosterone between bulls with homogeneous and heterogeneous parenchyma. In bulls with homogeneous parenchyma, hair DHEA-S concentration was positively correlated with percentage motile sperm (R² = 0.76), progressively motile sperm (R² = 0.70), and motility yield (R² = 0.71). The findings indicate that the integration of testicular ultrasonography and hair DHEA-S status in the BBSE could provide a more comprehensive assessment of indicative fertility in bulls. Additionally, ultrasonography can be used in the BBSE when the evaluation of semen parameters is not available.

The latest intrauterine fetal developmental stage and the neonatal period represent the most challenging phases for mammalian offspring. Toward the term of pregnancy, during parturition, and after birth, the hypothalamic–pituitary–adrenal axis (HPA) is a key system regulating several physiologic processes, through the production of cortisol and dehydroepiandrosterone (DHEA). This study was aimed to assess DHEA concentrations in hair and claws of 126 spontaneously dead newborn puppies, classified as premature puppies (PRE-P), stillborn puppies (STILL-P) and puppies that died from the 1st to the 30th day of life (NEON-P). The possible influence of newborn sex, breed body size, and timing of death on DHEA concentrations in both matrices was evaluated. Claw DHEA concentrations were higher in the PRE-P group when compared to STILL-P and NEON-P puppies (p < 0.05), whilst no significant differences were found in hair for all the studied factors. The results confirm the hypothesis that higher amounts of DHEA are produced during the intrauterine life in dogs, also in puppies that will die soon after birth.