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Aglepristone was administered in bitches during the follicular phase to evaluate its effects on progesterone, estradiol‐17β and LH serum concentrations. Ten German Shepherds were divided into two groups (treated n = 5; control n = 5). Treated bitches received 10 mg/kg BW of aglepristone subcutaneously during the early follicular phase, 24 hr after and then 7 days later. The control group was injected, at the same time periods, with saline solution (0.3 ml/kg BW). For the steroid evaluations, blood was collected daily from the onset of proestrus until the first day of cytological dioestrus. For LH base‐line serum determination, blood was also collected every 20 min for 2 hr at the onset of proestrus. For LH surge identification, blood was collected daily (every 6 hr) starting from the day of the first administration of aglepristone or saline solution until the first day of dioestrus. All animals ovulated but the treated group presented longer ovulation‐dioestrus intervals than the control group (5.2 ± 2.2 days p <.05). Serum concentrations of the evaluated hormones were similar between experimental animals except for serum LH. Indeed, no LH peaks were detected in the treated group while LH surges were clearly observed in the control group (9 ± 1 days after the beginning of proestrus. In particular, the area under the curve for LH was significantly lower in treated than control animals (12 ± 4 ng/ml x Day; p =.01). In conclusion, administrations of aglepristone during the follicular phase of the bitch does not affect the steroid hormone patterns but does prevent the occurrence of a LH surge. This work raises significant questions and opens perspectives concerning the mechanisms of ovulation in bitches. [ABSTRACT FROM AUTHOR]

The study of the immune response in several types of tumours has been rapidly increasing in recent years with the dual aim of understanding the interactions between neoplastic and immune cells and their importance in cancer pathogenesis and progression, as well as identifying targets for cancer immunotherapy. Despite being considered one of the most immunogenic tumour types, melanoma can progress in the presence of abundant lymphocytic infiltration, therefore suggesting that the immune response is not able to efficiently control tumour growth. The purpose of this study was to investigate whether the density, distribution and grade of tumour‐infiltrating lymphocytes (TILs) in 97 canine melanocytic tumours is associated with histologic indicators of malignancy and can be considered a prognostic factor in the dog. As a further step in the characterization of the immune response in melanocytic tumours, an immunohistochemical investigation was performed to evaluate the two main populations of TILs, T‐lymphocytes (CD3+) and B‐lymphocytes (CD20+). The results of our study show that TILs are present in a large proportion of canine melanocytic tumours, especially in oral melanomas, and that the infiltrate is usually mild. The quantity of CD20+ TILs was significantly associated with some histologic prognostic factors, such as the mitotic count, the cellular pleomorphism and the percentage of pigmented cells. Remarkably, a high infiltration of CD20+ TILs was associated with tumour‐related death, presence of metastasis/recurrence, shorter overall and disease‐free survival, increased hazard of death and of developing recurrence/metastasis, hence representing a potential new negative prognostic factor in canine melanocytic tumours. [ABSTRACT FROM AUTHOR]

Leptin regulates body weight and several physiological processes including reproduction. We evaluated the circulating levels of leptin in pregnant and non‐pregnant bitches as well as their correlation with body weight, food intake and number of foetuses. Nineteen healthy German shepherd bitches were used and divided in two groups (pregnant n = 12 and non‐pregnant n = 7). Blood samples were collected every 15 days starting from ovulation (Day 0) throughout pregnancy (pregnant group, P) or throughout luteal phase (non‐pregnant group, NP) In pregnant bitches, leptin concentrations increased from the day of ovulation (1.32 ± 0.06 ng/ml) up to day 45 (1.51 ± 0.06 ng/ml; p <.01) and returned to baseline values from day 60 post‐ovulation. In non‐pregnant bitches, leptin concentrations remained constant throughout the whole observation period (estimated marginal mean ± SE=1.33 ± 0.38 ng/ml). Pairwise comparisons showed significant differences between P and NP at day 45 post‐ovulation (p <.05). Multivariable models indicated that, controlling for time and litter size, there was a positive relationship between leptin concentration and BW (p <.05) although Pearson coefficients showed that the correlation between BW and leptin was only significant in NP animals at day 45 (r = 0.76, p <.05). The multivariable approach also suggested that, holding BW and time constant, leptin concentrations tend to increase as the number of puppies increased (p =.06). Our study supports indirectly the contribution of the feto‐placental unit to the circulating maternal leptin concentration. [ABSTRACT FROM AUTHOR]

Contents: This is the first time that PAG determination using two different antisera raised against PAG molecules purified from both caprine (RIA‐706) and bubaline placentas (RIA‐860) is reported in water buffalo. Ninety‐eight buffalo cows, belonging to a buffalo herd subjected to a synchronization and artificial insemination (AI) programme, were enrolled in this study. Blood samples were taken on days 0 (AI), 23, 25, 28, 30 and 45. Pregnancy was confirmed by ultrasonography on days 28 and 45. The blood of 20 buffaloes that had calved was tested every five days from the day of calving until day 50 postcalving. Differences in PAG concentrations were observed between pregnant and nonpregnant buffaloes starting from day 23 post AI using both RIA‐706 and RIA‐860 (p < 0.001). However, estimated mean concentrations of PAG measured by RIA‐706 were higher than RIA‐860 (p < 0.001) and Bland–Altman analysis showed biases ranged from 0.0 ng/ml at day 23 to 0.79 ng/ml at day 28 post AI. Moreover, RIA‐706 showed greater sensitivity and accuracy both at 23 and 25 days of pregnancy. RIA‐706 and RIA‐860 decreased below 1 ng/ml from 40 and 30 days postpartum, respectively, suggesting that PAG are better recognized by the antisera raised against the caprine PAG in the postpartum period also. This is essential when using PAG as an appropriate marker of early pregnancy after postpartum for detecting new pregnancies. The results of this study show that the ability of RIA systems to recognize early PAG could be improved using antisera raised against PAG molecules isolated from caprine placenta. [ABSTRACT FROM AUTHOR]

Contents: Throughout gestation, changes in foetal umbilical cord Doppler parameters in ewes were detected. Doppler ultrasonography of the umbilical artery was performed weekly starting at 18 weeks before parturition until birth. In the foetal umbilical artery (UA), systolic peak velocity (SPV), end diastolic velocity (EDV), increased (p for within‐subjects effect <0.001) while pulsatility index (PI) resistance index (RI) decreased (p for within‐subjects effect <0.001) with the progress of pregnancy. A linear trend was found on all patterns (p < 0.001). In particular, the EDV values increased significantly (p < 0.05) with respect to previous weeks, at weeks 16, 11, 10, 7, and 1 before parturition. The SPV values increased significantly (p < 0.05), with respect to previous observations, at weeks 11, 10, and 7 before parturition. Finally, the PI and RI decreased significantly (p < 0.05) only at week 7 before parturition. The increased velocities and reduced resistance index suggest a progressive increment in blood flow to the foetus towards the end of pregnancy. Foetal and utero‐placental vascular parameters can be reliably evaluated using high‐frequency ultrasound. [ABSTRACT FROM AUTHOR]