Stimulatory effects of fasting on vascular endothelial growth factor (VEGF) production by growing pig ovarian follicles

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Climatology of snow depth and water equivalent measurements in the Italian Alps (1967-2020)

A climatology of snow water equivalent (SWE) based on data collected at 240 gauging sites was performed for the Italian Alps over the 1967-2020 period, when Enel routinely conducted snow depth and density measurements with homogeneous methods. Six hydrological sub-regions were investigated spanning from the eastern Alps to the western Alps at altitudes ranging from 1000 to 3000 m a.s.l. Measurements were conducted at fixed dates at the beginning of each month from 1 February to 1 June and on 15 April. To our knowledge, this is the most comprehensive and homogeneous dataset of measured snow depth and density for the Italian Alps. Significant decreasing trends over the years at all fixed dates and elevation classes were identified for both snow depth, equal to - 0.12 +/- 0.06 m per decade, and snow water equivalent, equal to - 51 +/- 37 mm per decade, on average in the six macro-basins we selected. The analysis of bulk snow density data showed a temporal evolution along the snow accumulation and melt season, but no altitudinal trends were found. A Moving Average and Running Trend Analysis (MARTA triangles), combined with a Pettitt's test change-point detection, highlighted a decreasing change of snow climatology occurring around the end of the 1980s. The comparison with winter temperature and precipitation data from the HISTALP dataset identified a major role played by temperature on the long-term decrease and changing points of snow depth and SWE with respect to precipitation, mainly responsible for its variability. Correlation with climatic indexes indicates significant negative values of the Pearson correlation coefficient with winter North Atlantic Oscillation (NAO) and positive values with winter Western Mediterranean Oscillation (WeMO) for some areas and elevation classes. Results of this climatology are synthesized in a temporal polynomial model that is useful for climatological studies and water resources management in mountain areas

Different approaches for assessing sperm function

Different approaches can be used to assess sperm function in different conditions, i.e. sperm storage, freezing-thawing or activation by induction of capacitation and acrosome reaction. In this review we will focus on the assays routinely performed in our laboratories, giving a literature support to critically analyse different approaches. In fact, researchers usually tend to look for the \u201cone shot\u201c parameter that could explain itself a specific process; it is our conviction that a multiparametric approach is still more valid, as some changes in sperm function are very complex and could be explained only by operating in different ways. Sperm motility, the most evident sperm characteristic, should be assessed by computer-aided sperm analysers that permit an objective evaluation of the motility and its kinematic parameters. Commercial and open source instruments are available and could be profitably used together with specific statistical approaches. The use of microscopy, and particularly fluorescent microscopy, could be a very useful tool to assess different parameters in sperm cells both by fluorophores that give indication of a determined function, and by immunolocalization of proteins, that permits the discover of new features or to explain particular sperm functions. The same substrates could be used also in flow cytometry: the difference is that it permits to study wider sperm populations (and their sub-population distribution). Flow cytometry is undergoing a very wide use in spermatology and technical and experimental rigor is needed to obtain reliable results. Metabolic assessment of sperm features, particularly energetic supply, ATP formation and other enzyme activities, could represent a very important challenge to acquire new information and complete/integrate those derived from other techniques. Finally, functional assays such as oocyte binding and in vitro fertilization, represent a very strong tool to assess sperm function in vitro, as they could evidence the functional intactness of some pathways

Comparative analysis of some methods for deriving the expected flood reduction curve in the frequency domain

International audienceThis article compares the results of three different models, namely empirical, geomorphoclimatic and stochastic, proposed in the literature for synthesising the reduction curve of average river discharges, of given frequency, over different durations. The analysis used observed reduction ratios inferred for twelve recording gauge stations with known rating curves, situated on central Italian watercourses all of which flow into the Adriatic sea. Particular emphasis was laid on the difficulties encountered in the parameterisation of the models, on the relations between the different formulations and on the existence of a link between the model parameters and the characteristic response times of the basins

EFFECTS OF RESVERATROL ON VITRIFIED PORCINE OOCYTES

Vitrified MII porcine oocytes are characterized by reduced developmental competence, associated with the activation of the apoptotic pathway. Resveratrol (R), a polyphenolic compound present in several vegetal sources, has been reported to exert, among all its other biological effects, an antiapoptotic one. The aim of this study was to determine the effects of R (2\u2009\ub5M) on the apoptotic status of porcine oocytes vitrified by Cryotop method, evaluating phosphatidylserine (PS) exteriorization and caspases activation. R was added during IVM (A); 2\u2009h postwarming incubation (B); vitrification/warming and 2\u2009h postwarming incubation (C); all previous phases (D). Data on PS exteriorization showed, in each treated group, a significantly higher (P<0.05) percentage of live nonapoptotic oocytes as compared with CTR; moreover, the percentage of live apoptotic oocytes was significantly (P<0.05) lower in all R-treated groups relative to CTR. The results on caspase activation showed a tendency to an increase of viable oocytes with inactive caspases in B, C, and D, while a significant (P<0.05) increase in A compared to CTR was recorded. These data demonstrate that R supplementation in various phases of IVM and vitrification/warming procedure can modulate the apoptotic process, improving the resistance of porcine oocytes to cryopreservation-induced damage

A polyphenol-rich extract from an oenological oak-derived tannin influences in vitro maturation of porcine oocytes

Tannins have been demonstrated to have antioxidant and various health benefit properties. The aim of this study was to determine the effect of an ethanol extract (TRE) of a commercial oenological tannin (Quercus robur toasted oak wood, Tan'Activ R \uae ) on female gamete using an in vitro model of pig oocyte maturation (IVM) and examining nuclear maturation, cytoplasmic maturation, intracellular GSH and ROS levels and cumulus cell steroidogenesis. To this aim, during IVM performed in medium either supplemented (IVM A) or not supplemented (IVM B) with cysteine and \u3b2-mercaptoethanol, TRE was added at different concentrations (0, 1, 5, 10, 20 \u3bcg/ml). The addition of TRE at all the concentration tested to either IVM A or IVM B, did not influence oocyte nuclear maturation. When IVM was performed in IVM A, no effect was induced on cytoplasmic maturation by TRE at the concentration of 1, 5 and 10 \u3bcg/ml, while TRE 20 \u3bcg/ml significantly reduced the penetration rate after IVF (p &lt; 0.05) and the blastocyst rate after parthenogenetic activation (p &lt; 0.01). Oocyte maturation in IVM B, compared to IVM A group, decreased GSH (p &lt; 0.001) and increased ROS (p &lt; 0.01) intracellular levels and in turn impaired oocyte cytoplasmic maturation reducing the ability to sustain male pronuclear formation after IVM (p &lt; 0.001) and the developmental competence after parthenogenetic activation (p &lt; 0.001). TRE supplementation to IVM B significantly reduced ROS production (5, 10, 20 \u3bcg/ml TRE) to levels similar to IVM A group, and increased GSH levels (10, 20 \u3bcg/ml TRE) compared to IVM B (p &lt; 0.05) without reaching those of IVM A group. TRE supplementation to IVM B at the concentrations of 1, 5 and 10 \u3bcg/ml significantly improved (p &lt; 0.001) oocyte cytoplasmic maturation enhancing the ability to sustain male pronuclear formation without reaching, however, IVM A group levels. TRE addition at all the concentration tested to both IVM A and IVM B, did not induce any effect on E2 and P4 secretion by cumulus cells suggesting that the biological effect of the ethanol extract is not exerted thought a modulation of cumulus cell steroidogenesis. In conclusion, TRE, thanks to its antioxidant activity, was partially able to reduce the negative effect of the absence of cysteine and \u3b2-mercaptoethanol in IVM B, while TRE at high concentration in IVM A was detrimental for oocyte cytoplasmic maturation underlying the importance of maintaining a balanced redox environment during oocyte maturation

Overstocking dairy cows during the dry period affects dehydroepiandrosterone and cortisol secretion

Stressful situations trigger several changes such as the secretion of cortisol and dehydroepiandrosterone (DHEA) from the adrenal cortex, in response to ACTH. The aim of this study was to verify whether overstocking during the dry period (from 21&nbsp;\ub1&nbsp;3 d to the expected calving until calving) affects DHEA and cortisol secretion and behavior in Holstein Friesian cows. Twenty-eight cows were randomly divided into 2 groups (14 animals each), balanced for the number of lactations, body condition score, and expected date of calving. Cows in the far-off phase of the dry period (from 60 to 21 d before the expected calving date) were housed together in a bedded pack. Then, animals from 21&nbsp;\ub1&nbsp;3 d before the expected calving until calving were housed in pens with the same size but under different crowding conditions due to the introduction of heifers (interference animals) into the pen. The control condition (CTR) had 2 animals per pen with 12.0&nbsp;m2 each, whereas the overstocked condition (OS) had 3 interference animals in the same pen with 4.8&nbsp;m2 for each animal. On d 1230&nbsp;\ub1&nbsp;3, 1221&nbsp;\ub1&nbsp;3, 1215&nbsp;\ub1&nbsp;3, 1210&nbsp;\ub1&nbsp;3, and 125&nbsp;\ub1&nbsp;3 before and 10, 20, and 30 after calving, blood samples were collected from each cow for the determination of plasma DHEA and cortisol concentrations by RIA. Rumination time (min/d), activity (steps/h), lying time (min/d), and lying bouts (bouts/d) were individually recorded daily. In both groups, DHEA increased before calving and the concentration declined rapidly after parturition. Overstocking significantly increased DHEA concentration compared with the CTR group at d 1210 (1.79&nbsp;\ub1&nbsp;0.09 vs. 1.24&nbsp;\ub1&nbsp;0.14 pmol/mL), whereas an increase of cortisol was observed at d 1215 (3.64&nbsp;\ub1&nbsp;0.52 vs. 1.64&nbsp;\ub1&nbsp;0.46&nbsp;ng/mL). The OS group showed significantly higher activity (steps/h) compared with the CTR group. Daily lying bouts tended to be higher for the OS group compared with CTR group in the first week of treatment. The overall results of this study documented that overstocking during the dry period was associated with a short-term changes in DHEA and cortisol but these hormonal modifications did not influence cow behavior

Effects of short- and long-term fasting on the ovarian axis and reproductive performance of rabbits does

To assess the impact of acute nutritional challenges on reproductive performance, 116 rabbit does were randomly assigned to either \u201ccontrol\u201d or two \u201cfasting\u201d groups. In the control group, the does were fed ad libitum (AL) while in the treated groups the animals were fasted for 24 (STF) or 48 h (LTF) before artificial insemination (AI). In both treated groups, the rabbits were re-feed 2 hours before AI, which was performed at day 11 post partum (pp) in STF does and at day 32 or 55 pp in LTF does following GnRH injection to induce ovulation. In a parallel experiment, blood samples were collected from 10 rabbits/groups by catheterization of the central ear vein at 15 min intervals for 4 h prior and after GnRH, then at hourly intervals for other 4 h, and again 24 and 48 h later to measure LH, estradiol-17b? and leptin. The expression of estradiol-17b receptors (ER) was evaluated by immunohistochemistry in the hypothalamus and anterior pituitary obtained from both control and treated rabbits after 24 and 48 h of fasting. The 24-h long fasting reduced receptivity (55.8 vs. 70.9%), fertility rate (42.8 vs. 59.2%) especially in does with parity =4 (50 vs. 80%; P=0.05), and kits born alive (6.6 vs. 7.7). Also the does fasted for 48 h, showed lower fertility (31.2 vs. 52,6 %) and litter size at birth (8.7 vs. 9.6) than controls. Following GnRH injection, the LH peak was higher in AL and STF than in LTF does (Mean \ub1 SEM, 39.3\ub117.04 vs. 31.3\ub13.39 and 12.2\ub11.23 ng/ml, respectively). Estradiol-17b showed higher pulse frequency and amplitude in AL than in STF and LTF does. Toward the end of fasting, mean plasma leptin concentrations were lower (P\ua30.01) in both STF and LTF does than in control rabbits (0.82\ub10.19, 1.20\ub10.1, and 2.32\ub10.33 ng/ml, respectively), but then gradually increased in both treated groups following re-alimentation. Compared to controls or STF does, ER-like immunoreactivity decreased in the ventromedial nucleus of LTF rabbits, but increased in the medial preoptic area. ER expression was greatly reduced in the anterior pituitary of LTF does

Milk production in saanen goats treated with repeated low doses of intermediate-release insulin during early lactation

The effect of insulin administration on the productive responses of Saanen goats during early lactation was investigated. Ten of 20 adult females were subjected to subcutaneous administration of intermediate-acting insulin (0.14UI/kg body weight) at 2, 9, and 14 days postpartum. Milk yield was measured twice daily for 13 weeks and milk samples were collected to measure protein and fat contents. Plasma levels of progesterone, insulin, non-esterifies fatty acids, glucose and other metabolites were measured. Results showed a significantly increased effect of insulin treatment on the content of milk fat and protein; moreover, milk production in the first and second postpartum weeks were higher than control group. The peak of lactation in the insulin group was achieved one week earlier in comparison to the control group. In addition, the milk production rate showed lower persistency (milk yield 13 week/milk yield at peak) in the same group. During the first four weeks of postpartum, treated animals showed greater weight loss and higher non-esterified fatty acid concentration, whereas no effect was observed on the concentration of progesterone and other metabolites. The above results indicated that repeated administration of insulin in dairy goats during early lactation increase yield and qualitative components of milk, but has substantial consequences on animal productive rate and metabolic response