Expression of the Vascular Endothelial Growth Factor (VEGF‐A) and its Receptors in the Umbilical Cord in the Course of Pregnancy in the Pig

The umbilical cord (UC) and the placenta are important organs through which respiratory gases, nutrients, wastes and biologically active substances are exchanged between the maternal and the foetal system. A rapid placental vascularization observed in the second half of pig pregnancy is positively correlated with the mRNA expression of the vascular endothelial growth factor (VEGF). Based on these findings, we hypothesized that VEGF may have a stimulatory effect in the dynamically growing UC. To further understand the role of the VEGF–VEGFR system during UC development, mRNA and protein expression as well as the cellular localization of VEGF‐A, VEGFR‐1 and VEGFR‐2 in UC were examined on days 40, 60, 75 and 90 of pregnancy and after physiological delivery in the pig (day 114 of pregnancy). Real Time RT‐PCR analysis showed an increase in the mRNA levels of VEGF120 and VEGF164 from day 90 of pregnancy. VEGFR‐1 mRNA expression was significantly increased on day 75 of pregnancy. No significant changes in VEGFR‐2 mRNA expression were detected. In turn, western blot analysis revealed an increase in VEGF‐A protein expression on day 40, compared to the later days of pregnancy. A rapid increase in the VEGFR‐1 protein level was noted on day 75 and 90 of gestation. No significant changes in VEGFR‐2 protein expression were detected on any of the analysed days of pregnancy. Immunohistochemical staining enabled detection of VEGF–VEGFR system, in endothelial and tunica media cells of the umbilical vessels and in allantoic duct and amniotic epithelium on all analysed days of pregnancy. Positive reactions for VEGF‐A and VEGFR‐1, but not VEGFR‐2, were also observed in myofibroblasts. In conclusion, this data shows that members of the VEGF–VEGFR system are temporally and spatially well localized for playing key roles during umbilical cord formation and its intensive growth observed after day 75 of pregnancy.     

Response of Thawed Epidi dymal Red Deer Spermatozoa to Increasing Concentrations of Hydrogen Peroxide,and Importance of Individual Male Variability

Oxidative stress represents a challenge during sperm manipulation. We have tested the effect of increasing hydrogen peroxide (H₂O₂) levels on red deer spermatozoa after cryopreservation, and the role of male‐to‐male variation in that response. In a first experiment, eight thawed samples were submitted to 0, 25, 50, 100 and 200 μm H₂O₂ for 2 h at 37°C. Intracellular reactive oxygen species (H₂DCFDA‐CM) increased with H₂O₂ concentration, but we only detected a decrease in sperm function (motility by CASA and chromatin damage by sperm chromatin structure assay) with 200 μm . Lipoperoxidation assessed by the thiobarbituric acid reactive substance (TBARS) method increased slightly with 50 μm H₂O₂ and above. In a second experiment, samples from seven males were submitted to 0 and 200 μm H₂O₂ for 2 h, triplicating the experiment within each male. Males differed at thawing and regarding their response to incubation and H₂O₂ presence. We found that the kinematic parameters reflected male‐to‐male variability, whereas the response of the different males was similar for lipid peroxidation and viability. A multiparametric analysis showed that males grouped differently if samples were assessed after thawing, after incubation without H₂O₂ or after incubation with H₂O₂. Red deer spermatozoa are relatively resilient to H₂O₂ after thawing, but it seems to be a great male‐to‐male variability regarding the response to oxidative stress. The acknowledgement of this individual variability might improve the development of optimized sperm work protocols.     

Caecal disease in equids

Objective To review the breed, age, gender, clinical and laboratory findings, treatment and outcome of horses with caecal disease presented to a referral centre. Design Retrospective study of 96 cases. Procedure The breed, age, and gender of the study population were compared with the corresponding hospital population for the same period. The means (± SD) for clinical and laboratory findings were recorded for each caecal disorder. Treatment was categorised as medical or surgical, and outcome was recorded. Results Caecal diseases included impaction (40% of total cases), rupture associated with concurrent unrelated disease (13%), rupture with parturition (9%), rupture with no associated disease (5%), infarction (11%), torsion (9%), abscess or adhesion (7%), tumour (3%), and miscellaneous conditions (3%). The breed or gender of affected horses did not differ from the hospital population, although horses > 15 years were more frequently represented (P < 0.05). This age group was specifically more predisposed to caecal impaction (P < 0.05), as were Arabian, Morgan, and Appaloosa breeds (P < 0.05). In horses with caecal impaction transrectal examination was the most useful diagnostic procedure; 90% of affected horses treated medically were discharged while horses treated by typhlotomy alone, or typhlotomy and blind end ileocolostomy, had survival rates to discharge of 71% and 86%, respectively. Horses with caecal rupture associated with concurrent un-related disease showed no signs of impending rupture; all were receiving phenylbutazone, all were euthanased, and 50% had caecal ulceration at necropsy. Of horses with caecal rupture with parturition 56% had prior dystocia; in two-thirds the site of rupture was the ileocaecal junction and all were euthanased. Horses with caecal rupture with no associated disease died or were euthanased; rupture was idiopathic. Horses with caecal infarction usually had signs of abdominal pain and abdominal fluid changes consistent with peritonitis; transrectal examination was nonspecific, and typhlectomy was successful in seven of eight horses. Horses with caecal torsion had signs of severe, acute abdominal pain and typhlectomy was successful in three of five horses. Diagnosis of caecal adhesion or abscess was assisted by transrectal palpation in two of seven horses and surgical treatment was successful in two of five horses. A caecal tumour was diagnosed in three horses aged 20 years or older that presented with chronic weight loss. Other caecal diseases were uncommon. Conclusion Caecal disease is uncommon in equids but some specific features of the history and physical findings can alert the veterinarian to the possibility of caecal involvement in horses with gastrointestinal dysfunction. Medical or surgical therapy can be effective in horses where caecal rupture has not occurred.     

An epizootic of bovine ephemeral fever in New South Wales in 2008 associated with long-distance dispersal of vectors

Objective To report the rapid transmission of bovine ephemeral fever ( BEF) virus from north-western New South Wales south to the Victorian border in January 2008 and to present data that suggests an uncommon meteorological event caused this rapid southward dispersal of vectors. Procedure The locations of reported clinical cases, data from sentinel herds and results from a survey of cattle in the southern affected area were examined to delineate the distribution of virus transmission. Synoptic weather charts for January 2008 were examined for meteorological conditions that may have favoured movement of vectors in a southerly direction. Results Cases of BEF and exposure to BEF virus in NSW were confirmed west of the Great Dividing Range, extending from the Queensland border to Finley, on the far North Coast and around the Hunter Valley. A low-pressure system moved south across the state on 18–19 January 2008, preceding the first cases of BEF in the south of NSW by 1–2 days. Conclusion Heavy rainfall in December 2007 provided a suitable environment for vector breeding, resulting in the initiation of and support for continuing BEF virus transmission in north-western NSW. The movement of a low-pressure system south across central western NSW in mid-January 2008 after the commencement of BEF virus transmission in the north-west of the state provided a vehicle for rapid southward movement of infected vectors.