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Abstract: The aim of this study was to assess hair cortisol concentrations in New Zealand white rabbits (Oryctolagus cuniculus) that were subjected to relocation and surgery to evaluate HPA-axis activity; in addition, we used this marker of cortisol secretion to evaluate the allostatic load of animals undergoing surgery. After a period of acclimatisation, which lasted 40 days from their arrival at the enclosure, 19 rabbits were subjected to T1–T12 dorsal arthrodesis (RS), 19 were sham-operated (SS), and 19 were non-operated (CON). Hair samples were collected at the time of arrival (ST1) at the animal facility, and seven other sets of hair samples were collected at 40-day intervals from the same area of skin for a period of 240 days as re-shaved hair (anagen phase): immediately before surgery (ST2) and after the surgery (ST3, ST4, ST5, ST6, ST7, and ST8). The transition from the rabbitry to the animal breeding facility led to a significant increase in cortisol concentration (ST2) in all of the groups. At ST3, the RS group presented higher cortisol concentrations than those of the SS group and the CON group. At ST4, the experimental groups showed similar values that remained constant until ST8. The results show that the management of rabbits undergoing surgery should be evaluated very carefully, and hair cortisol concentrations may provide a means of avoiding the dangerous cumulative effects of additional stressors close to surgery.
Found in: ključnih besedah
Keywords: animal welfare, cortisol, hair, HPA axis, rabbit, surgery
Published: 09.02.2018; Views: 3269; Downloads: 0
Fulltext (186,99 KB)

Abstract: Hypothalamus-pituitary-adrenal (HPA) axis of both mother and fetus, is one of key mechanisms involved in fetal programming. Cortisol, the end-product of this axis, plays a critical role in regulating fetal and new-born metabolism and development. The aim of the study was to evaluate maternal and fetal cortisol concentrations shortly after delivery on hair samples non-invasively collected. The study was carried out on 11 pairs of beef cows and their calves (calves were 12 because of one case of twins) from the same farm and subjected to the same managerial conditions. Hair from new-born calves and from their mothers was collected on the day of birth shaving their withers to the level of the skin. The hair cortisol concentrations (HCC) were determined by RIA as previously described (Peric et al. 2013: J Dairy Sci 96:3023–3027). The results showed that fetal and maternal HCC ranged from 16.11 to 40.43 pg/mg and from 1.88 to 15.73 pg/mg respectively, with fetal and maternal mean ± SE HCC of 23.72 ± 2.21 and 6.40 ± 1.32 pg/mg respectively (p < 0.001). Fetal HCC were on average 3.5 higher than those of mothers but this ratio differed among the pairs. These differences were also found among the twin calves. These results indicate that in beef cows-and-calves pairs, although HCC at delivery were always higher in calves than in cows, the ratio between fetal and maternal HCC differs among pairs, suggesting an individuality in the fetal programming processes that may also rely on genetic and epigenetic factors.
Found in: ključnih besedah
Keywords: hair, cortisol, cattle, delivery
Published: 09.04.2019; Views: 2562; Downloads: 0
Fulltext (802,60 KB)

Abstract: During their life, birds face several challenges which can threaten the stability of physiological functions. These situations typically trigger a cascade of endocrine secretions involving the hypothalamic–pituitary–adrenal (HPA) axis, and resulting in the release of both cortisol and corticosterone also in birds. The use of a non-invasive approach to collect samples of biological material derived from natural populations represents a greatly combination for an improvement of knowledge avoiding handling animals. Steroid concentrations in feathers are mainly acquired from the capillary around the follicle during the long period of feather grown reflecting their bloodstream concentrations. Accordingly, a chronic HPA axis activation could be assessed using molted feathers cortisol concentrations. Another hormone, dehydroepiandrosterone (DHEA), is secreted by adrenals and it could be assessed in molted feathers. This study was aimed to evaluate the feasibility of using feathers cortisol and DHEA concentrations to provide a retrospective assessment of the activity of the HPA axis in griffon vulture acquired for health monitoring purposes. For this, we introduced two groups of animals with a known health condition: one group composed by griffons that have experienced a long-term physiologically compromised period (PC group; n=8) and the other group composed by griffons physiologically not compromised (CTRL group; n=9). The feathers cortisol and DHEA analyses were carried out using RIA [1,2] adapted for feathers. The results revealed different feather hormone concentrations between the two groups of animals. The feathers cortisol had a median value higher in the PC group than in the CTRL group, with cortisol concentrations showing a central value 1.6 times higher in those animals that suffered a long-term physiological impairment. The PC group showed also (Kruskal- Wallis test) higher feather concentrations of DHEA (P=0.01) than the CTRL group. Pearson’s correlation coefficients were used to examine the associations between cortisol and DHEA, showing no correlation between cortisol and DHEA feather concentrations in the PC group (r=0.18, P=0.34) and a moderate positive correlation in the CTRL group (r=0.51, P=0.011). In conclusion, our study reveals that molted feathers can be an interesting way to evaluate the physiological status of wild animals by using a non-invasive approach. Our analyses reveal that in addition to cortisol also DHEA could be evaluated to better understand the relationships between these hormones and to determine the resilience condition of wild species.
Found in: ključnih besedah
Keywords: CORTISOL, DHEA, GRIFFON VULTURE, Gyps fulvus, FEATHER
Published: 09.04.2019; Views: 2336; Downloads: 0
Fulltext (4,05 MB)

Abstract: Attention must be paid to C-section anesthesia effects on mother and offspring. Alfaxalone induction results in improved puppy viability when compared to propofol. The present study aims to evaluate effects of alfaxalone or propofol induction for elective C-section on newborns, expressed as Apgar score and fetal fluids cortisol concentration. Anesthesia was induced with alfaxalone 3 mg/kg iv in 5 bitches (group A), and propofol 4 mg/kg iv in another 5 (group P), maintained with isoflurane. Amniotic and allantoic fluids were collected to determine cortisol concentration. Apgar score, litter size, newborn gender, birth-weight, maternal age, and parity were recorded. ANOVA, U Mann-Whitney test and ANCOVA assessed the effects of drugs on the Apgar score and fetal fluids cortisol. Thirty-six puppies were randomly selected for the study: 16 from group A and 20 from group P. Only the Apgar score significantly differed between groups. ANCOVA confirmed a significantly higher Apgar score in group A underlining the influence of fetal fluids cortisol concentrations, both resulting in covariates. Present results confirm the effect of anesthesia on the Apgar score of newborns, which is significantly higher for alfaxalone than propofol, suggesting the use of fetal fluids cortisol as a covariate. These findings could be a starting point for further investigations when less viable puppies are detected or expected, such as during an emergency C-section. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.
Found in: ključnih besedah
Summary of found: ...expressed as Apgar score and fetal fluids cortisol concentration. Anesthesia was induced with alfaxalone 3...
Keywords: Alfaxalone, Apgar score, C-section, Canine neonates, Cortisol, Fetal fluids
Published: 26.11.2019; Views: 2075; Downloads: 87
Fulltext (234,45 KB)