Morphology of Reproductive Organs,Semen Quality and Sexual Behaviour of the Male Rabbit Exposed to a Soy‐containing Diet and Soy‐derived Isoflavones during Gestation and Lactation

Placental and breastfeeding transfer of soy isoflavones are potential routes for animal and human exposure to phytoestrogens, and reproductive dysfunctions have been linked to early exposure to these compounds. So, the aim of this study was to investigate the effects of perinatal (intrauterine and lactational) exposure to soy‐containing diet and soy‐derived isoflavones on the reproductive parameters of male rabbits. For this purpose, 12 female rabbits were randomly assigned to receive: (1) a soy‐ and alfalfa‐free diet (control diet); (2) a soy‐ and alfalfa‐free diet supplemented with 10 mg/kg body wt/day of soy isoflavones; (3) a soy‐ and alfalfa‐free diet supplemented with 20 mg/kg body wt/day of soy isoflavones; and (4) a diet containing 18% of soy meal, throughout gestation and lactation. Weight and morphology of the reproductive organs of some of the male offspring were evaluated at weaning (between days 29 and 31). The remaining males were placed on the control diet from weaning to adulthood (gestational and lactational exposure only). Sexual behaviour, semen quality and reproductive organs’ morphology were evaluated after puberty. There were no significant differences in litter size and gestation duration between control and treatment groups. Perinatal exposure to soy‐containing diet and soy isoflavones did not alter testis, epididymides, proprostate and prostate weight and gross morphology. After puberty, sexual behaviour and semen parameters did not differ significantly from the control group. These results indicate that intrauterine and lactational exposure to soy‐containing diet and soy‐derived isoflavones may not adversely affect reproductive development and function of male rabbits.     

Effects of meiotic inhibitors and gonadotrophins on porcine oocytes in vitro maturation,fertilization and development

This study evaluated the effect of three reversible meiotic inhibitors (MINs) and their interaction with gonadotrophins (Gns) on the meiotic maturation and developmental competence of porcine oocytes. In experiment 1, the oocytes were matured for 22 hr in the presence or absence of dbcAMP (1 mM), cycloheximide (7 μM) or cilostamide (20 μM) with or without Gns, and for an additional 22 hr in the absence of MINs and Gns. At 22 hr of maturation, regardless of the presence of Gns, a higher proportion (p < .001) of oocytes cultured in the presence of MINs were effectively arrested at the germinal vesicle stage compared with the oocytes cultured without MINs. At 44 hr of maturation, the proportion of oocytes that reached MII was higher (p < .05) in groups with Gns compared with groups without Gns. In experiment 2, oocytes that were matured as in experiment 1 were inseminated and cultured for 7 days to evaluate fertilization parameters and blastocyst formation. Only oocytes from the dbcAMP + Gns group had higher (p < .05) efficiency of fertilization compared with the other treatment groups. The presence of dbcAMP during maturation also increased (p < .05) blastocyst formation and efficiency of blastocyst formation in both the presence and absence of Gns. These results indicate that the interaction of Gns with the tested MINs improved meiotic progression. In addition, regardless of supplementation with Gns, the presence of dbcAMP during the first maturation period increased and even doubled the capacity of oocytes to develop to the blastocyst stage.     

Effects of Developmental Stage, Embryonic Interferon-τ Secretion and Recipient Synchrony on Pregnancy Rate after Transfer of in vitro Produced Bovine Blastocysts

Three separate trials of bovine embryo transfers were performed consisting of 32, 41 and 33 transfers, respectively, to examine the effects of (a) the developmental stage of in vitro‐derived blastocysts, (b) the amount of interferon‐τ (IFN‐τ) they secreted during culture and (c) the cyclic stage of the recipient at the time of transfer on the probability of establishment of pregnancy. One blastocyst was transferred into the ipsilateral uterine horn to the CL. At the time of transfer, blastocysts were classified into one of three developmental stages (early blastocyst, blastocyst and expanded blastocyst) and the cyclic stage of each cow was assessed (?12 h, on time, +12 h, +24 h, >24 h). Prior to the second and third trials, blastocysts were individually cultured for 24 h in 50 μl medium droplets and the IFN‐τ concentration in the droplet was determined. Logistic regression analyses revealed that expanded blastocysts had a significantly higher likelihood of establishing pregnancy (p = 0.009), and that there was a significant interaction with the cyclic stage of the recipient in this group with lower rates of pregnancy resulting from decreasing synchrony with the recipient (p = 0.033). IFN‐τ secretion during culture was significantly higher in expanded blastocysts than in the other two groups (p < 0.05). A significant effect of the pre‐transfer level of IFN‐τ secretion was found only in the ‘Blastocyst’ group where transfer of embryos with lower IFN‐τ production prior to transfer resulted in higher pregnancy rates (p = 0.047). These results demonstrate that IFN‐τ secretion may be a useful tool to predict pregnancy outcome, but only within certain developmental stages.     

Pentaborate Polyanion in the Crystal Structure of Ulexite, NaCaB5O6(OH)6{middle dot}5H2O

Triclinic ulexite crystals contain isolated borate polyanions [B(5)O(6)(OH)(6)](3-) related to the well known pentaborate polyanion [B(5)O(6)(OH)(4)](-) by addition of two hydroxyl groups to two opposite B-O triangles. The isolated ulexite polyanions form the [B(5)O(7)(OH)(4)](n)(3n-) chains previously found in crystals of the related mineral probertite, NaCaB(5)O(7)(OH)(4).3H(2)O.     

Stratospheric Mean Ages and Transport Rates from Observations of Carbon Dioxide and Nitrous Oxide

Measurements of stratospheric carbon dioxide (CO2) and nitrous oxide (N2O) concentrations were analyzed to investigate stratospheric transport rates. Temporal variations in tropospheric CO2 were observed to propagate into the stratosphere, showing that tropospheric air enters the lower tropical stratosphere continuously, ascends, and is transported rapidly (in less than 1 month) to both hemispheres. The mean age A of stratospheric air determined from CO2 data is approximately 5 years in the mid-stratosphere. The mean age is mathematically equivalent to a conserved tracer analogous to exhaust from stratospheric aircraft. Comparison of values for A from models and observations indicates that current model simulations likely underestimate pollutant concentrations from proposed stratospheric aircraft by 25 to 100 percent.     

Efficacy of metoclopramide for treatment of ileus in horses following small intestinal surgery: 70 cases (1989–1992)

Summary: In this retrospective study, postoperative ileus was studied in horses having resection of the small intestine followed by a jejunojejunal (n=35) or a jejunocaecal (n=35) anastomosis. Twenty-six horses received no metoclopramide, 27 received metoclopramide as an intermittent intravenous infusion and 17 horses received metoclopramide as a continuous intravenous infusion (0.04 mg/kg/hour). Horses receiving a continuous infusion of metoclopramide had a reduced total volume (P< 0.001), shorter duration (P< 0.001), and a slower rate (P< 0.001) of postoperative gastric reflux, and a shorter postoperative hospital stay (P< 0.01) when compared to horses receiving no metoclopramide and horses receiving metoclopramide as an intermittent infusion. Horses having jejunocaecostomy performed had a larger volume (P< 0.05), longer duration (P< 0.05), and a greater rate (P< 0.05) of postoperative gastric reflux, and a longer postoperative hospital stay (P< 0.001) than horses undergoing jejunojejunostomy. Horses that had an abdominal drain placed during surgery had a longer length of intestine resected (P< 0.05) and a longer postoperative hospital stay (P< 0.05) than horses without an abdominal drain. Horses that died or were euthanased during the postoperative period had a greater total volume (P< 0.05), longer duration (P< 0.05), and greater rate of postoperative gastric reflux (P< 0.01), a longer length of small intestine resected (P< 0.01), and a shorter postoperative hospital stay (P< 0.05) than horses that survived until discharge from the hospital. In a multivariate regression analysis the continuous infusion of metoclopramide was the only variable that contributed significantly to predicting the total volume (P< 0.001; r²= 0.24), duration (P< 0.001; r²= 0.24) and rate (P< 0.001; r²= 0.25) of postoperative gastric reflux. We concluded that metoclopramide given as a continuous intravenous infusion decreased the incidence and severity of ileus following small intestinal resection and anastomosis in horses.     

Seroprevalence of equine herpesvirus 1 in Thoroughbred foals before and after weaning

Objective To investigate the seroprevalence of equine herpesvirus 1 in foals around weaning and after weaning on two large Thoroughbred farms using a type-specific enzyme-linked immunosorbent assay to determine exposure to infection.
Design A longitudinal population study in groups of Thoroughbred weanling foals.
Study population Two hundred weanling Thoroughbred foals from a population of about 380 foals were enrolled on two adjacent stud farms in the Hunter Valley of New South Wales. Foals on both farms were weaned from February to May 1995 into randomly selected groups of 10 to 15 foals. Farms were selected because of their willingness to cooperate in the survey and because their detailed records of foals and their movements. They were representative of well-managed large Thoroughbred stud farms in New South Wales. Both studs had upper respiratory tract disease among weanling foals around weaning each year although the sero-prevalence of viral respiratory disease on either farm was not known before the study.
Procedure Serum was collected from foals within each group at fortnightly intervals from 9th February until 1st June 1995, and at a single follow-up period in August 1995. Each sample was tested in triplicate using an antibody-detection ELISA which is type-specific for EHV-1 and EHV-4 antibodies.
Results and conclusions There was serological evidence of EHV-1 infection both before and after weaning. The prevalence of EHV-1 antibody in the sample population increased during the study and individual cases of EHV-1 infection were identified. The increase was caused both by the seroconversion of foals within the groups and by the recruitment into the study of foals with pre-existing EHV-1 antibody. Evidence of EHV-1 infection in Thoroughbred foals after weaning has not been reported previously in Australia and this has implications for vaccination regimens.