Effects of beta-glucans ingestion (Saccharomyces cerevisiae) on metabolism of rats receiving high-fat diet.

We investigated the effects of beta-glucans (Saccharomyces cerevisiae) ingestion on metabolic parameters of Wistar rats receiving high-fat diet. The experimental period was divided into two stages: in the first one, the animals were divided into two groups containing 12 animals each. The first group received commercial feed and the second received high-fat diet containing 20% of pork fat during 60 days. At the end of this period, body weight, blood glucose and Lee index were assessed. In the second stage, those 24 animals were redivided into four groups: (C) - control diet; (CB) - control diet and treated with Beta-glucan (BG); (O) - obese animals and (OB) - obese animals treated with BG. Animals from groups CB and OB received 30 mg/kg of BG dissolved in saline solution by gavage. Animals from groups C and O received only saline solution for 28 days. The design used was totally randomized in 2 × 2 factorial scheme. Data were submitted to analysis of variance (anova). Animals from OB group showed inferior levels (p < 0.05) of total cholesterol (13.33%), triacylglycerols (16.77%) and blood glucose (23.97%) when compared to the animals from group O. The use of BG has provided smaller increase in Lee index (p < 0.05), without promoting alteration in feed and water consumption, organs weight, HDL-C, LDL+VLDL-C, carcass composition, villus/crypt ratio, and pancreas, kidney and stomach histology. BG from S. cerevisiae promoted beneficial metabolic effects in rats receiving high-fat diet.

Recovery, cryopreservation and fertilization potential of bovine spermatozoa obtained from epididymides stored at 5 degrees C by different periods of time.

The objetive of the present study was to evaluate the effect of the interval between animal's death and sperm recovery on the freezability and fertilizing ability of spermatozoa from bull epididymides stored for different periods of time. Testis from 25 bulls were collected at the abattoir 2h after the slaughter. In the laboratory spermatozoa from one epididymis were recovered and analysed for motility. The remaining epididymis was stored for 24h (G24), 48h (G48) and 72h (G72) at 5 degrees C. At the end of each time period, spermatozoa were recuperated and cryopreserved in Tris-egg yolk and glycerol. Pre-freeze and post-thaw sperm samples were taken to assess total and progressive motility, concentration, membrane integrity and acrosome integrity. For evaluation of fertilizing ability, in each time period five straws of each bull were thawed, pooled and used for in vitro embryo production. The results showed that after 48h of storage there was a decline in total motility, which did not change until 72h. Progressive motility, plasma membrane and acrosome integrity were not affected by any of the storage periods. Conversely, all sperm parameters, except progressive motility, were reduced after cryopreservation. Embryo production was less (P<0.05) in the treatments than in the reference group. However, there was no differences (P>0.05) in blastoycst rate among experimental groups. Considering all the embryos produced by epididymal spermatozoa a greater proportion of female embryos was observed, which was similar to the reference embryos. The shift observed on sex ratio toward female for those two groups was also observed when they were compared with the expected 1:1 ratio (P<0.05). The results showed the possibility to produced in vitro embryos using cryopreseved spermatozoa from epididymides and stored for long period of time at 5 degrees C. These procedures became an important tool for animal preservation when the sperm cells cannot be cryopreserved immediately after the animal's death.