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Najdeno v: osebi
Ključne besede: dlaka, kortizol, krave molznice
Objavljeno: 16.06.2016; Ogledov: 2876; Prenosov: 14
Polno besedilo (0,00 KB)

Najdeno v: osebi
Ključne besede: kortizol dlake, proizvodnja semena, semenčece
Objavljeno: 16.06.2016; Ogledov: 2506; Prenosov: 14
Polno besedilo (0,00 KB)

Najdeno v: osebi
Ključne besede: rastni hormon, plazemske koncentracije, žrebeta
Objavljeno: 16.06.2016; Ogledov: 2552; Prenosov: 12
Polno besedilo (0,00 KB)

Opis: Traditional superovulation protocols that include multiple gonadotropin treatments are time-consuming and labor intensive. These protocols require multiple handling and restraining of embryo donors. This will likely increase the risks of injuries in both animals and humans and induce stress that may lead to a reduced superovulatory response. These are more evident when working with cattle that are rarely handled or raised on extensive grazing. The objectives of this experiment were to compare the efficacy of a split-injection protocol of porcine pituitary-derived porcine FSH (pFSH) preparation (slow release [SR] group) to the traditional 4-day treatment with pFSH administered twice daily (C group) and to determine the concentrations of cortisol in the hair as a marker of activation of the hypothalamic-pituitary-adrenal (HPA) axis during the two superovulatory treatments. Thirty-two heifers were stimulated twice in a 2 × 2 crossover design and compared for ovarian response and numbers and characteristics of recovered ova-embryo among treatments. No differences between SR and C groups were found in terms of percentage of responsive animals (100% vs. 93.8%) and ovulation rate (83.7 ± 1.1 vs. 79.5 ± 1.0%). A positive correlation was found between the number of follicles responsive to pFSH (2-8 mm) at the beginning of treatments and the superovulatory response, and no differences were found in these follicular populations between the two treatment groups. The numbers of CLs, ova-embryos, fertilized ova, transferable and freezable embryos recovered per cow were found to be significantly higher in SR compared with C group (14.0 ± 1.6 vs. 10.6 ± 1.0, 12.1 ± 1.6 vs. 7.6 ± 1.0, 11.1 ± 1.1 vs. 7.3 ± 1.0, 9.6 ± 1.4 vs. 6.6 ± 1.0, and 9.4 ± 1.4 vs. 6.0 ± 1.0 for SR and C group, respectively). The SR group produced also a significantly greater number of excellent- and/or good-quality embryos compared with the C group. The concentrations of cortisol in the hair at Days 14 and 21 were significantly greater in the C compared with the SR group (P < 0.05). In conclusion, these results indicate that the dilution of gonadotropin in a 5% hyaluronan solution, reducing the administration frequency, improves the quantitative and qualitative superovulatory response of Marchigiana heifers. Further studies using other breeds of cattle are needed to verify the results herein obtained and to confirm the lower activation of the hypothalamic-pituitary-adrenal axis caused in the donor by the split-injection protocol.
Najdeno v: osebi
Ključne besede: Beef heifer, Bovine, Hair cortisol, Hyaluronic acid, Slow release, Superovulation
Objavljeno: 01.03.2016; Ogledov: 2654; Prenosov: 227
Polno besedilo (403,15 KB)
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Opis: 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.
Najdeno v: osebi
Ključne besede: DIET, HAIR, CORTISOL, DHEA, MOUSE
Objavljeno: 21.07.2016; Ogledov: 3031; Prenosov: 0
Polno besedilo (3,65 MB)