Effect of resveratrol supplementation in conventional slow and ultra-rapid freezing media on the quality and fertility of bull sperm.

The study investigated the impact of resveratrol (RES) on bull sperm cryopreservation employing conventional slow (CS) and ultra-rapid (UR) freezing methods on sperm quality and in vitro fertility. Twenty-four ejaculates from four bulls were divided into four groups based on the cryopreservation method and RES addition: CS-RES (n = 80), CS-Co (n = 80), UR-RES (n = 24), and UR-Co (n = 24). The CS freezing involved exposing sperm straws with 5% glycerol to liquid nitrogen (LN2) vapors, while UR freezing submerged sperm drops with 100 mM sucrose directly into LN2. Overall, sperm kinematic parameters and integrity of plasma and acrosome membranes significantly decreased (P < 0.001) after cryopreservation. Post-thaw values of motilities (total [TM] and progressive [PSM]), velocities (curvilinear and straight-line), beat cross frequency (BCF), and sperm with intact plasma membrane/intact acrosome (PI-/PNA-) were higher (P < 0.05) with CS-RES and CS-Co treatments compared to UR-RES and UR-Co treatments. CS-RES treatment resulted in greater percentages (P < 0.05) of TM, PSM, PI-/PNA-, and fertility (blastocyst rate) than their control, CS-Co; while UR-RES showed higher BCF values (P < 0.05) than its control, UR-Co. Additionally, UR-RES treatment exhibited lower oxidative stress percentages than UR-Co (P < 0.05). This study presents the following conclusions: (1) the CS freezing resulted in better cryosurvival of bull sperm than UR freezing; (2) the RES supplementation to CS freezing medium improved sperm motility, membrane integrity, and fertility; and (3) despite low cryosurvival sperm and fertility, the RES addition to ultra-rapid freezing medium reduced oxidative stress.

Effect of Agroindustrial Waste Substrate Fermented with Lactic Acid Bacteria and Yeast on Changes in the Gut Microbiota of Guinea Pigs.

The aim of the study was to evaluate the impact of probiotics obtained from an agroindustrial waste substrate fermented with lactic acid bacteria and/or yeasts on the health and changes in the microbiota of the digestive tract of guinea pigs. Eighty male guinea pigs, Kuri breed, 30 days old and 250 g live weight, were randomly selected and divided into four groups of 20 animals each: T0, control; T1, Lactobacillus acidophilus and L. bulgaricus; T2, Saccharomyces cerevisiae and Kluyveromyces fragilis; and T3. L. acidophilus, L. bulgariccus, S. cerevisiae and K. fragilis. T1, T2 and T3 contained molasses-vinasse substrate in their base, the dose administered was 1.00 mL/animal orally every 3 days. The indicators evaluated were weight gain, occurrence of diarrhea and mortality, macroscopic lesions in the digestive tract organs and changes in the microbiota of the stomach, caecum, small and large intestine. Treatments T1, T2 and T3 improved weight gain (p < 0.05) and reduced the presence of guinea pigs with diarrhea (p < 0.05) and there was no mortality; animals in the control group presented a greater amount (p < 0.05) of macroscopic lesions in the digestive tract organs; in the T1, T2 and T3 groups there was an improvement in the natural microbiota. It is concluded that the inclusion of a microbial additive in young guinea pigs improves intestinal health and consequently improves weight gain, reduces diarrhea and deaths and normalizes the natural microbiota of the gastrointestinal tract.

Cryopreservation of dog epididymal spermatozoa by conventional freezing or ultra-rapid freezing with nonpermeable cryoprotectant.

This study was aimed to assess the effectiveness of two methods for cryopreservation of dog epididymal spermatozoa, one by conventional freezing (CF) with shortening both equilibration and cooling times, and the other by ultra-rapid freezing (URF) with nonpermeable cryoprotectant. Sixty epididymides were recovered from thirty orchiectomized adult dogs and the sperm samples were retrieved by retrograde flushing using TCG-EY (tris, citric acid, glucose + 20% egg yolk) extender and then 20 pools were conformed. Each pool was divided into 2 aliquots and then cryopreserved by CF and URF methods respectively. The CF method maintained the cooled-pool samples for 2h (1h without and 1h with 5% glycerol) and then were frozen by liquid nitrogen (LN2) vapors for 2 min. The URF method cryopreserved the cooled-pool samples using TCG-EY+250 mM sucrose, equilibrating during 30 min (5 °C) and submerging 30-µL drops directly in LN2. The results showed that the URF method produced a lower percentage of total and progressive motilities and acrosome integrity (P < 0.05) than the CF method. However, the kinetic variables (curvilinear and straight-line velocities, straightness, linearity, wobble, amplitude of lateral head displacement, and beat-cross frequency) and plasma membrane integrity did not differ (P > 0.05) between both cryopreservation methods. Unlike the URF method, the width, area and perimeter of sperm head were reduced after the CF method (P < 0.05). In conclusion, despite the low motility achieved after the ultra-rapid freezing method, the similar values of kinetic, viability and head morphometric dimensions to those obtained after conventional freezing, suggest that ultra-rapid freezing with sucrose may be a useful alternative for the cryopreservation of canine epididymal sperm.

Seasonal predictability of the East Atlantic pattern from sea surface temperatures.

This study analyzes the influence of sea surface temperatures (SSTs) on the second mode of atmospheric variability in the north Atlantic/European sector, namely the East-Atlantic (EA) pattern, for the period 1950-2012. For this purpose, lead-lag relationships between SSTs and the EA pattern, ranging from 0 to 3 seasons, were assessed. As a main result, anomalies of the EA pattern in boreal summer and autumn are significantly related to SST anomalies in the Indo-Pacific Ocean during the preceding seasons. A statistical forecasting scheme based on multiple linear regression was used to hindcast the EA-anomalies with a lead-time of 1 to 2 months. The results of a one-year-out cross-validation approach indicate that the phases of the EA in summer and autumn can be properly hindcast.

Changes in present and future circulation types frequency in northwest Iberian Peninsula.

The aim of the work described herein was to study projection scenarios in order to find changes in the synoptic variability of the northwest Iberian Peninsula in the 21st century. To this end, we investigated the changes in the frequency of the different circulation types computed for the study area using three different models used in the IPCC 4(th) assessment report. The circulation types were computed using the procedure known as Lamb circulation types. The control simulation for the late 20th century was evaluated objectively from the results obtained using data from the NCEP/NCAR reanalysis, as to evaluate the ability of the model to reproduce the present climate. We have compared not only seasonal mean sea level pressure fields but also the mean seasonal frequency of circulation types. The results for the end of the 21st century show a decrease in the frequency of cyclonic, W, and SW circulation types in the spring and summer months. This trend also appears in the autumn, with a concomitant increase in the anticyclonic types.