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Abstract: Obesity and MetS (Metabolic Syndrome) are both linked to persistent long-term hormonal and metabolic changes. In most of the studies, cortisol (C) and dehydroepiandrosterone (DHEA) concentrations have been measured in obese and normal-weight subjects, obtaining heterogeneous results. Plasma, saliva and urine, matrices that represent timepoint or short-term steroids exposure, were used for these studies. The aim was to study C, DHEA and C/DHEA ratio of mice pups in the hair, matrix capable of providing cumulative hormonal exposure. Sixty C57Bl/6 mice pups (30 males and 30 females) were housed in a temperature-controlled environment (22±2°C) and on a 12h light/dark schedule, under ad-libitum access to food and water for 16 weeks (welfare: Italian Law Decree 116-92 and EC Directive 86-609-EEC). Control and experimental diets were offered immediately after weaning (3 weeks old pups), for 16 weeks. Four experimental checkpoints were established (T1: 4 weeks, T2: 8 weeks, T3: 12 weeks and T4: 16 weeks of diet). T3 and T4 showed the hormonal concentrations of pubertal animals. Twentyseven pups (13 females and 14 males) were randomly group-housed in cages (6 for T1, 5 for T2, 6 for T3, 10 for T4) and assigned to control diet (CTRL: D12328, Research Diets, New Brunswick, NJ). 33 pups (17 females and 16 males) were randomly group-housed in cages (5 for T1, 6 for T2 and T3, 16 for T4) and assigned to the HFHC diet (HFHC: D12331, Research Diets, New Brunswick, NJ - plus 42g/L fructose/sucrose in drinking water). At each experimental checkpoint, all the animals of one cage for each experimental group were suppressed. Hair strands were carefully cut with scissors as close as possible to the skin from the back of the mice, paying attention to not to wound the animals. Hair was stored in an envelope at RT in a dry room until use. C and DHEA hair concentrations was measured by a solid-phase microtiter RIA assay (Peric et al., 2016 adapted in the mouse). Only at 8 weeks the HFHC group showed significantly higher C concentrations than the CTRL group (1.56±0.06 vs 1.92±0.130 pg/mg; P<0.05). DHEA concentrations were significantly reduced in the HFHC group than the CTRL group at 4 (114.64±13.93 vs 69.08±5.33 pg/mg; P<0.05), 8 (71.67±7.08 vs 50.38±4.74 pg/mg; P<0.05), 12 (73.27±8.29 vs 41.59±1.60 pg/mg; P<0.01) and 16 weeks (65.26±3.35 vs 55.05±1.84 pg/mg; P<0.05). The C/DHEA ratio was significantly increased in the HFHC than the CTRL group, at 8 (0.023±0.002 vs 0.040±0.005; P<0.01), 12 (0.024±0.003 vs 0.036±0.004; P<0.05) and 16 weeks (0.019±0.001 vs 0.025±0.002; P<0.01). The gender effect was not significant. Taking into account the lag time required for the hair emersion from the skin (about 1 week), the significant stimulation of the C at 8 weeks in the HFHC group refers to its chronic elevation from 5 to 7 weeks of treatment when the animals were not pubertal. Conversely, DHEA shows a chronic reduction in obese mice leading to consider an independent adrenal regulation of C and DHEA, both stimulated by ACTH. Research was supported by the Project CBM (MIUR DM60643). Peric et al. 2016 J Appl Anim Welf Sci 18:1-8.
Found in: osebi
Keywords: DIET, HAIR, CORTISOL, DHEA, MOUSE
Published: 21.07.2016; Views: 4183; Downloads: 0
Fulltext (3,65 MB)

Abstract: The aim of this research has been to evaluate the presence of anomalies in the ovarian cycle activity during postpartum and to verify whether 72-hr dietary fasting during the dominance phase, the phase before ovulation, might modify the ovarian follicle population. The presence of anomalies in ovarian cycle activity has been evaluated in 30 Italian Friesian cows starting from 20 days postpartum until 211 days of lactation. Long oestrus and brief dioestrus or scarce luteal activity have been the main anomalies found through measuring progesterone concentrations in the whey. Until 100 days of lactation, the BCS values of the problematic animals have been significantly lower than those in animals with normal ovarian activity. After 100 days of lactation, the ovarian anomalies continued to appear despite the fact that all the animals have reached comparable BCS values. Starting from the results of this trial, the effect of 72-hr dietary fasting on dominant follicles has been studied in six cows. Ultrasonography revealed that the diameter of the follicles at 71 days postpartum has been significantly lower than at 181 days. A 72-hr dietary restriction at 101 and 211 days postpartum did not affect the size of the dominant follicle. However, at 101 days postpartum, half of the animals presented follicular cysts. The effect of fasting differed if the animal has been in early postpartum or 211 days of lactation. Further researches are necessary to understand how different metabolic conditions can modify the follicular population but on the other hand the study shows the utility for farmers and field veterinarians of monitoring the resumption of the ovarian cycle postpartum through the whey progesterone concentrations.
Found in: osebi
Keywords: dairy cow, cyclic activity, follicles, fasting
Published: 06.04.2017; Views: 3704; Downloads: 0
Fulltext (651,67 KB)

Abstract: This study was conducted in order to assess the changes of cortisol and dehydroepiandrosterone (DHEA) concentrations in hair of Italian Simmental dairy cows managed indoor in tie-stall barns or grazing on high mountain pasture. In experiment I, animals were kept in tie-stalls throughout the year (n = 27). In experiment II, animals remained on mountain pastures during summer (from 20th June to 20th September) and then kept indoors in tie-stalls for the rest of the year (n = 18). At the end of July, following vertical transhumance, dairy cows were moved to a pasture located at a higher altitude. In the two studies, hair samples, obtained using clippers from the animal's forehead, were collected on the 20th June (P1), 20th July (P2), 20th August (P3), 20th September (P4) and 20th October (P5) and analysed for cortisol and DHEA. In experiment I, DHEA concentration was unaffected by sampling time (P > 0.05), whereas, cortisol/DHEA ratio was similar between P1 and P2 (P > 0.05) and then increased during the experimental period reaching the highest value at P5 (P < 0.05). In experiment II, dairy cows had higher concentration of DHEA during grazing compared to cows kept indoors (P < 0.05), conversely cortisol/DHEA ratio decreased from P1 to P2 (P < 0.05), remained constant from P2 to P3 (P > 0.05) and then increased from P3 to P4 (P < 0.05), the highest value was recorded at P5. In conclusion, cortisol and DHEA concentrations and their ratio measured in the hair of dairy cows can be useful to evaluate the allostatic load in animals managed indoor in tie-stall barn or grazing on mountain pasture.
Found in: osebi
Keywords: Dairy cow, Mountain pasture, Hair, Cortisol, DHEA
Published: 28.05.2017; Views: 3980; Downloads: 0
Fulltext (205,07 KB)

Abstract: Biometric measurements of horn, body and physiological variables of 35 Alpine ibex, Capra ibex ibex, (14 females and 21 males, age range: 2-15 years) were analysed in relation to gender and area of origin. Moreover, for the first time hair cortisol concentration was evaluated in this species. The ibexes were live-captured in spring in the Maritime Alps Natural Park. All the horn and body morphometric measurements were significantly different between genders and a statistical difference was found between horn and body data considering the area of origin of ibexes, with the exception of horn circumference and height as well of body and hock length. Among the physiological variables, female ibex showed higher heart rate and glycemia, but tended to have lower respiratory rate than male. The mean hair cortisol concentration was 22.40±1.44 pg/mg (±SE). A different distribution was described for the male hair cortisol concentrations compared to that in females. Obtained data indicate that the geographical area where Alpine ibex lives could affect the endurance of an ibex population but further investigations are needed to understand if intra- and inter-specific competition and different environment could be the basis of the HPA axis activation. Hair cortisol evaluation together with biometric values could be an interesting way to obtain information on the adaptation that the animal attempts to reach in relation to environmental factors and pursuing organism homeostasis. This feature could be important in attempting to preserve wildlife biodiversity that also depends from the state of animal welfare.
Found in: osebi
Keywords: allostatic load, Alps, ibex, biometry, hair cortisol
Published: 06.03.2018; Views: 3608; Downloads: 0
Fulltext (1,11 MB)

Abstract: Although steroidogenesis in maternal, placental and fetal compartments is interdependent, the maternal and fetal hypothalamic-pituitary-adrenal (HPA) axes represent separate biological systems, with dehydroepiandrosterone (DHEA) recognized as the main fetal steroid. Fetal steroids are likely to influence development and have long-term effects on HPA function. Hair analysis represents a promising methodological approach for the non-invasive measurement of steroids, allowing for a retrospective analysis of the total exposure to steroids over time, and avoiding the influence of acute events or circadian fluctuations (Schury et al. 2017, BMC Psychiatry 17:213). Hair coat DHEA (hcD) concentrations have been investigated in cows (Peric et al. 2017, Livestock Sci 202:39–43), but no studies have been performed on newborn calves. Hair samples of 12 beef calves (7 males, 5 females) were collected by shaving at calving (T0) and monthly up to 10 months of age (T1-T10), only on the re-growth area. Hair DHEA was analyzed by RIA2. Statistical analysis revealed that hcD concentrations in calves were influenced by age, with higher levels at T1 and T2 compared to the other samples (p < 0.05). HcD levels were not influenced by newborn gender, birth weight and Apgar score. These data demonstrate that DHEA is quantifiable in the hair coat of newborn calves, and that hcD levels are influenced by the age of calves. The higher accumulation of DHEA was detected from birth to 2 months of age, suggesting that DHEA continues to be secreted by the newborn calf also beyond birth and could be involved in the events occurring during the first months of age.
Found in: osebi
Keywords: hair, dehydroepiandrosterone, cattle, calf
Published: 09.04.2019; Views: 2530; Downloads: 0
Fulltext (4,53 MB)