Adrenal Gland Ultrasonographic Measurements and Plasma Hormone Concentrations in Clinically Healthy Newborn Thoroughbred and Standardbred Foals.

Adrenal hormones, ACTH plasma concentrations and the ultrasonographic evaluation of the adrenal glands are considered complementary in clinical evaluations of the hypothalamic-pituitary-adrenal (HPA) axis function in several species. In dogs, age, size and weight have a significant effect on the ultrasonographic size of the adrenal glands. In neonatal foals, ultrasonographic evaluation and measurements of the adrenal glands have been demonstrated to be reliable; however, the effect of individual variables on ultrasonographic features has not been investigated, and the clinical usefulness of adrenal gland ultrasonography is still not known. The aims of this study were: (i) to provide and compare adrenal glands ultrasound measurements in healthy newborn Thoroughbred and Standardbred foals, and assess any effect of age, weight and sex on them; (ii) to assess and compare ACTH and steroid hormone concentrations in healthy neonatal foals of the two breeds. Venous blood samples and ultrasonographic images of the adrenal glands were collected from 10 healthy neonatal Thoroughbred and 10 healthy neonatal Standardbred foals. Ultrasonographic measurements of the adrenal glands were obtained and adrenocorticotropin (ACTH), cortisol, dehydroepiandrosterone (DHEA), progesterone (P4) and aldosterone plasma concentrations were assessed. The ACTH/cortisol, ACTH/progesterone, ACTH/aldosterone, ACTH/DHEA and cortisol/DHEA ratios were calculated. A significant positive correlation was found between the height of the right adrenal gland and the foal's weight; the width of the right and left adrenal gland and the medulla was significantly lower in Thoroughbreds than in Standardbreds. Cortisol and ACTH plasma concentrations were significantly higher and lower, respectively, in Thoroughbreds compared with Standardbreds. The cortisol/DHEA ratio was significantly higher in Thoroughbreds. This study provides reference ranges for neonatal Thoroughbred and Standardbred foals, and suggests the presence of breed-related differences in ultrasonographic adrenal gland measurements, plasmatic cortisol and ACTH concentrations. The higher cortisol/DHEA ratio detected in Thoroughbred foals could suggest a different response to environmental stimulation in the two breeds.

Ultrasonographic measurement of the adrenal gland in neonatal foals: reliability of the technique and assessment of variation in healthy foals during the first five days of life.

BACKGROUND: Adrenal gland ultrasonographic measurements are useful in clinical evaluation of patients with adrenal dysfunction in several species. In human healthy neonates, the ultrasonographic size of the adrenal glands decreases during the first days of life. Ultrasonography of adrenal glands was demonstrated to be feasible in neonatal foals. The aims of this study were to describe a technique for ultrasonographic measurement of adrenal gland size to test its reliability in neonatal foals, and to assess any variation of ultrasonographic measurements during the first five days of life in healthy foals. METHODS: First, measurements of the adrenal glands were retrospectively obtained by three observers in 26 adrenal gland images of 13 healthy and sick neonatal foals. The interobserver and intraobserver agreement were tested. Later, adrenal gland ultrasonographic images and measurements were acquired by one operator in 11 healthy neonatal foals at one, three and five days of life and differences among the measurements obtained at the different time points were assessed. RESULTS: Interobserver agreement ranged from fair to excellent (0.48-0.92), except for cortex width (<0.4); intraobserver agreement ranged from good to excellent (0.52-0.98). No significant differences were found among the measurements obtained at one, three and five days of life. CONCLUSION: Adrenal glands ultrasonographic measurements can be obtained consistently in equine neonates, and in contrast to people they do not vary during the first five days of life in healthy foals.

Steroids in pig hair and welfare evaluation systems: combined approaches to improve management in pig breeding?

The aim of the present pilot study was to determine the allostatic load by analysing the hair cortisol and dehydroepiandrosterone­sulphate (DHEA­S) of commercial pigs belonging to different farms having good overall animal welfare according to the CREnBA (Centro di Referenza Nazionale per il Benessere Animale - Brescia, Italy) assessment protocol. The study was conducted on 86 pigs belonging to three farms with a grade higher than 8 on the CReNBA welfare evaluation system. Hair samples were taken by shaving on sows 1­10 days after weaning (Farms 1 and 2) and at the age of 8­10 months (Farm 3). The hormone concentrations were measured by radioimmunoassay. From the box plots, it is evident that the hair cortisol concentrations of animals were different between farms. Conversely, the variability of the hair DHEA­S concentration was similar between the F1 and F2 farms but much lower at F3. For all the variables considered (cortisol, DHEA­S and cortisol/DHEA­S ratio), F2 showed a higher hair concentration level than F1 (P < 0.05). The study's results indicate that the measurement of cortisol and DHEA­S in pig hair shows a different allostatic load between them, although the official welfare evaluation method assessed the farms as having good overall animal welfare.

Analysis of 19 Minerals and Cortisol in Red Deer Hair in Two Different Areas of the Stelvio National Park: A Preliminary Study.

The aim of the study was to perform an investigation on the concentration of 19 minerals and cortisol in red deer (Cervus elaphus) hair, a matrix that is easy to collect with non-invasive and painless sampling, able to represent an integrative values of long-term substance concentrations, and able to give useful information, also when performed on dead animals, given its extreme stability over time. In the study thirty-five animals were included, coming from two different sides of a valley in the Stelvio National Park, where official water analysis had pointed out elevated concentrations of As in one of the two orographic sides. Hair cortisol concentrations were measured using a RIA(Radio Immuno Assay), while minerals were detected using ICP-MS (Inductively Coupled Plasma- Mass Spectrometry). Results showed a negative relationship between cortisol and some mineral concentrations (Li, Co, As, Cd, Cr and Tl) and significant differences in some mineral concentrations between park areas (Al, Co, Cu, Cd and Ni). As, Cr and cortisol differences approached statistical significance. This preliminary study represents a step forward in the study of wildlife allostatic load and a valid method for applications in wildlife management programs, in environmental studies and in public health programs.

Cortisol, DHEA, and Sexual Steroid Concentrations in Fattening Pigs' Hair.

The aim of this study was to analyze the feasibility and reliability of using hair as a matrix to determine the dehydroepiandrosterone (DHEA) and sexual steroid concentrations and the cortisol/DHEA ratio in fattening pigs. The results could be also used to plan future research to identify threshold values in order to set up strategies to control the allostatic load and increase the resilience of fattening pigs before slaughter. The study was conducted on 107 commercial crossbred rearing pigs. The hair samples were taken by shaving at the age of 36 weeks, and concentrations of the hormones were measured using a solid-phase microtiter radioimmunoassay. Females had significantly higher cortisol levels (p < 0.01), significantly lower DHEA concentrations (p < 0.05) and significantly higher cortisol/DHEA ratios (p < 0.01) than barrows. Progesterone was significantly higher in gilts than in barrows (p < 0.01). Testosterone and 17ß-estradiol were significantly higher in barrows than in gilts (p < 0.05). If future research can produce threshold values for the different markers examined, the evaluation of animals under subclinical stress conditions will be possible.

Hair cortisol and dehydroepiandrosterone concentrations in naturally Taenia solium infected pigs in Tanzania.

The aim of this study was to measure hair cortisol and dehydroepiandrosterone (DHEA) concentrations in naturally Taenia solium infected and non-infected control pigs and assess the effect of an environmental change on the aforementioned parameters. Three hair patches were obtained from 13 T. solium infected and 15 non-infected controls sows, respectively corresponding to 3 time points (prior to, at and approximately two weeks after arrival at the research facility). Cortisol and DHEA were extracted using methanol and analysed by radio immune assay. Mean hair cortisol concentrations were significantly lower (p<0.001) in T. solium infected (4.7±3.0pg/mg) compared to control pigs (9.0±3.7pg/mg) prior to arrival at the research facility, however no significant difference was observed between the two groups at arrival and after approximately two weeks. Similar patterns were also observed for DHEA concentrations (infected pigs 253.9±82.3pg/mg, control pigs 387.7±116.4pg/mg) (p<0.001). Results showed that lean animals had significantly higher cortisol concentrations in both groups, infected and controls pigs, while DHEA was not significantly different between lean and normal animals. Results of this study have shown that an environmental change could have an effect on pigs' hormonal levels suggesting an undergoing adaptation process. After the pigs were kept under the same conditions, fed and watered ad libitum, no significant differences were observed between the groups, but a drop in DHEA concentrations was observed in all the pigs. Weight however had an effect on cortisol levels as lean animals had significantly higher cortisol concentrations in both groups, compared to normal pigs.

Relocation and Hair Cortisol Concentrations in New Zealand White Rabbits.

To investigate how long relocation modified hair cortisol concentrations in New Zealand white rabbits, 19 rabbits were subjected to a change in their breeding facility at the beginning of the trial and then were kept under stable environmental conditions. Hair samples were collected at the time of arrival to the nonhuman animal facility and at 40-day intervals from the same skin area for up to 440 days after the animals' arrival to the facility. A period effect on the hair cortisol concentration was found (p < .01). The transfer of the rabbits to the new facility might have induced an increase in the hypothalamic-pituitary-adrenal axis activity (p < .01). A second increase in hair cortisol concentration (p < .01) occurred at 320 days, after a change of personnel at the facility that occurred at 280 days, which was the only environmental change. The relocation of rabbits to the facility resulted in a stress response leading to elevated cortisol levels. The effect of relocation on mean cortisol concentrations was exhausted within 120 days when all environmental factors were kept stable.

Anti-Mullerian hormone (AMH) concentration in follicular fluid and mRNA expression of AMH receptor type II and LH receptor in granulosa cells as predictive markers of good buffalo (Bubalus bubalis) donors.

High individual variability in follicular recruitment and hence in the number of embryos produced is a major factor limiting the application of reproductive technologies in buffalo. Therefore, the identification of reliable markers to select embryo donors is critical to enroll buffaloes in embryo production programs. Better understanding of factors involved in follicular growth is also necessary to improve the response to superovulation in this species. The aim of this work was thus to determine the anti-Mullerian hormone (AMH) concentration in follicular fluid (FF) recovered from different size follicles and evaluate the mRNA expression profiles of development-related (AMHR2, CYP19A1, FSHR, and LHR) and apoptosis-related genes (TP53INP1 and CASP3) in the corresponding granulosa cells (GCs) in buffalo. Another objective was to evaluate whether the AMH concentration in FF and gene expression of GCs is associated with the antral follicular count. Ovaries were collected at the slaughterhouse, and all follicles were counted and classified as small (3-5 mm), medium (5-8 mm), and large (>8 mm). Follicular fluid was recovered for AMH determination, and the mRNA expression of AMHR2, FSHR, LHR, CYP19A1, TP53INP1, and CASP3 was analyzed in GCs. The AMH concentration in FF decreased (P < 0.01) at increasing follicular diameter. The mRNA expression of AMHR2 and FSHR was higher (P < 0.05) in small follicles, whereas that of LHR and CYP19A1 was higher (P < 0.05) in large follicles. The intrafollicular AMH concentration was positively correlated with the antral follicular count (r = 0.31; P < 0.05). Interestingly, good donors (≥12 follicles) had a higher (P < 0.05) concentration of AMH and AMHR2 levels in small follicles and higher (P < 0.05) LHR levels in large follicles than bad donors (<12 follicles). These results suggest a potential use of AMH to select buffalo donors to enroll in embryo production programs, laying the basis for further investigations.

Hair cortisol level as a retrospective marker of hypothalamic-pituitary-adrenal axis activity in horse foals.

Stimulation of the hypothalamic-pituitary-adrenal (HPA) axis and elevated cortisol concentrations in fetal plasma are associated with foal maturity, viability and adaptation to independent life. However, non-invasive measurement of cortisol in hair samples has not yet been validated in horses. The current study developed a radioimmunoassay to analyse cortisol in horse hair and was used to measure cortisol hair concentration at birth and at 30 and 60 days of age as a retrospective study of HPA axis activity. Cortisol was detectable in the hair of foals from birth until 2 months, but decreased with time and varied greatly between individuals. Analysis of hair cortisol could be useful for non-invasive retrospective studies of HPA axis activity in perinatal horse.