The Efficacy of a 3ß-Hydroxysteroid Dehydrogenase Inhibitor for the Termination of Mid-Term Pregnancies in Dogs.

Progesterone (P4) is the only hormone needed to maintain pregnancy in dogs. Therefore, a competitive inhibitor of 3ß-hydroxysteroid dehydrogenase (3ß-HSD) could be a safe and effective option to terminate pregnancy by inhibiting P4 synthesis. To address this hypothesis, we investigated the efficacy of trilostane (TRL), a competitive inhibitor of 3ß-HSD, in terminating pregnancy in dogs. Twenty-one dogs between days 30 and 38 of pregnancy were randomly assigned to one of two treatment groups (trilostane (TRL) and aglepristone (AGL)) and an untreated control (CON) group (n = 7 dogs each). Fetal heart rates (FHRs) (measured at 12 h intervals) and serum P4 concentrations (measured at 6 h intervals) were evaluated. The pregnancy termination rates were 0% and 100% in the TRL and AGL groups, respectively. The decrease in the FHR in the TRL and AGL groups was significantly lower than that observed in the CON group. There was a marked decrease in P4 concentrations in the TRL group 6, 54, and 102 h after the initiation of treatment. The luteal expression of StAR appeared to be weaker in the AGL group than the CON group. In conclusion, although a treatment-induced decrease was observed in plasma P4 concentrations, a seven-day TRL treatment alone was not effective in terminating pregnancies. Further studies are needed on the effects of the prolonged administration of TRL with varying doses and frequencies for the termination of mid-term pregnancy in dogs.

Laparoscopic ovariectomy in dogs: comparison between single portal and two-portal access.

OBJECTIVE: To compare surgical times and perioperative complication rates of single portal access and 2-portal laparoscopic ovariectomy (LapOVE) in dogs using a bipolar vessel sealer/divider device, and to evaluate the performance of novice laparoscopists for right ovariectomy. STUDY DESIGN: Controlled clinical trial. ANIMALS: Female dogs (n=42). METHODS: Dogs were divided into groups: 1=single portal and 2=2 portal. LapOVE was performed using a 5 mm vessel sealer/divider device and a 10 mm operating laparoscope (Group 1) or a 5 mm laparoscope (Group 2). Dog characteristics (weight, body condition score, ovarian ligament fat score), operative time, and perioperative complication rate were compared between groups. Right ovariectomy duration was evaluated for 2 novice laparoscopists. RESULTS: No significant difference was found in mean total surgical time between group 1 (21.07 min/s) and group 2 (19.06 min/s). Factors significantly affecting times included body condition scores, ovarian ligament fat score, ovarian bleeding, and surgeon expertise. Minor complications (bleeding from ovaries or after splenic trauma) occurred and were similar in both groups. Bleeding was correlated to body condition score and ovarian ligament fat score. Interindividual differences were found among surgeons for right ovariectomy time. CONCLUSIONS: Single portal access LapOVE using vessel sealer/divider device is feasible, safe, and does not significantly increase total surgical time in comparison with 2-portal approach. Laparoscopic skills may play a role in ability to perform single portal LapOVE. CLINICAL RELEVANCE: LapOVE can be performed using single portal access.

Effect of oral misoprostol, alone or in combination with aglepristone, on mid-term pregnancy termination in cats.

OBJECTIVES: This study aimed to determine the efficacy and safety of oral misoprostol (MIS) administration in the induction of mid-term pregnancy termination in cats. METHODS: Twenty-eight cats that were pregnant for 30-40 days were allocated to four groups. The aglepristone (AGL) group (n = 7) received 10 mg/kg SC aglepristone q24h for two consecutive days. In the AGL+MIS group (n = 7), AGL (as administered in the AGL group) and MIS (200 µg/cat PO q12h until the start of abortion) were administered. The MIS200 (n = 7) and MIS400 groups (n = 7) received MIS (200 or 400 µg/cat misoprostol, respectively) alone PO q12h until the start of abortion. Blood samples were collected at the start of treatment (d0), 4 days after the start of treatment (d4) and on the day of complete abortion/end of administration (dA/d7). RESULTS: The efficacy of the treatment was 71.4% in the AGL group, 100% in the AGL+MIS group, 0% in MIS200 group and 57.4% in MIS400 group (P = 0.004). No significance was found in relation to the interval from treatment to the start/end of abortion and the duration of abortion in all groups. The most observed side effect was vomiting in both groups administered MIS, particularly in the MIS400 group (56.7%). Progesterone (P4) concentrations were reduced during the abortion, but not to basal levels, in all groups. P4 concentrations were significantly lower at dA/d7 in the MIS400 group compared with the AGL and AGL+MIS groups (P = 0.002). CONCLUSIONS AND RELEVANCE: The results obtained from this study showed that low doses of MIS do not induce abortions in cats but increase the effect of AGL. Although higher doses could terminate pregnancies, this also causes intense unwanted side effects. Therefore, the use of MIS alone as an abortifacient in cats is not recommended. For mid-term pregnancy termination in cats, the combination of misoprostol and aglepristone provides a more effective abortifacient than using either of them alone.

Effect of deslorelin on testicular function, serum dihydrotestosterone and oestradiol concentrations during and after suppression of sexual activity in tom cats.

Objectives The aim of the study was to evaluate the efficacy of a 4.7 mg deslorelin implant in tom cats. Methods Nine mature male cats were included in the deslorelin group and five cats in the control group. Before the study started, all cats were confirmed to have distinct sexually dimorphic behaviour. Blood samples were taken on the implantation day, at day 7 and at day 15, then monthly, in order to measure serum dihydrotestosterone (DHT) and 17beta(ß)-oestradiol concentrations. The deslorelin group (n = 9) was divided into two subgroups: five cats (cats 1-5) were neutered in the postimplantation period during suppression of sexually dimorphic behaviour, and four cats (cats 6-9) were neutered after re-expression of sexually dimorphic behaviour. The control group cats (n = 5) were castrated without administration of the implant. Results Sexually dimorphic behaviours ceased within a mean ± SD of 13-58 days (23.30 ± 14.17) after implantation. DHT concentration decreased within 30 days. The mean duration of suppression was 26.5 ± 7.42 months and reactivation coincided with increased DHT values reaching preimplantation concentrations within 1 month. 17ß-oestradiol concentrations significantly correlated with DHT concentrations ( P <0.01). For cats castrated during suppression of sexual behaviour, the length of the long axes of the nuclei of Leydig cells, the diameter of seminiferous tubules and the height of the epithelium of the seminiferous tubules did not change until 3-6 months after implantation, whereas at 12 and 32 months the measured values were even lower than in the control group. For cats castrasted after reactivation, the length of long axes of the nuclei of Leydig cells and the diameter of seminiferous tubules approached the values of the control group between 4 and 6 months after reactivation. Conclusions and relevance A deslorelin implant (4.7 mg) suppresses sexually dimorphic behaviour in tom cats without any side effects and with full reversibility; however, duration of suppression is highly individual.

Tarantula cubensis extract alters the degree of apoptosis and mitosis in canine mammary adenocarcinomas.

In the present study, 13 clinical cases of canine mammary adenocarcinoma were evaluated in order to understand the effect of Tarantula cubensis extract (TCE) on tumor tissue. Punch biopsies were taken from the tumors before treatment with TCE. Subcutaneous injections of TCE were administered three times at weekly intervals (3 mL per dog). Between days 7 and 10 after the third injection, the tumor masses were extirpated by complete unilateral mastectomy. Pre- and post-treatment tumor tissues were immunohistochemically assessed. The expression of B-cell lymphoma 2 (Bcl-2) was found to be higher in pre-treatment compared to post-treatment tissues (p < 0.01) whereas Ki-67 expression was lower in post-treatment tissues (p < 0.01). No significant differences in fibroblast growth factor or vascular endothelial growth factor expression were observed between pre- and post-treatment tissues (p > 0.05). The apoptotic index was determined to be low before treatment and increased during treatment. These results suggest that TCE may be effective for controlling the local growth of canine mammary adenocarcinoma by regulating apoptosis.