No abstract

Precise prediction of the time of onset of parturition in the bitch is of clinical importance. Many parturition management cases in clinical practice are presented in the last two weeks of pregnancy without a reliable estimate of the parturition date. The aim of this study was to assess the value of a single progesterone level in the blood plasma from a preparturient bitch to predict the time of onset of parturition. The temporal relationship between the decrease in the plasma progesterone levels and the time of cervical dilatation (TCD)-which correlates to the onset of stage 1 of parturition-was evaluated in 25 bitches in the preparturient period. Among bitches destined to reach TCD within 12 h there is a 2% probability of having a plasma progesterone level of 15.8 nmoL/L or above and a 6% probability of having a level of 8.7 nmoL/L or above. Conversely, if the level is below 8.7 nmoL/L there is a 99% probability of reaching TCD within 48 h and if the level is below 3.18 nmoL/L there is a 100% probability of reaching TCD within 24 h. These results allow the veterinary obstetrician to make prompt decisions in the management of parturition.

Although dog prostatic fluid decreases the longevity of ejaculated dog spermatozoa, it also increases their rate of motility and their fertility after vaginal insemination, as well as the fertility of epididymal spermatozoa after uterine insemination. These findings indicate a need to further characterize the effects of prostatic fluid on dog spermatozoa. This study was done to determine the effects (P < 0.05) of homologous prostatic fluid added prior to cooling, after thawing, or at both times to epididymal spermatozoa from 21 dogs. The

A I radioimmunoassay (RIA) has long been used to determine the value of progesterone in serum or plasma of bitches but was discontinued in 2014. A chemiluminescence immunoassay (CLIA) gained prominence since 2003 to determine the value of progesterone in serum of bitches but the assay changed in 2012. This study assessed the agreement between progesterone values obtained with RIA in plasma (progRIA) and with the post-2012 CLIA (progCLIA) in the serum of bitches. ProgCLIA was determined in 110 serum samples from 40 bitches in pro-oestrus or early oestrus and compared to progRIA in plasma samples collected from the same bitches at the same time, where progRIA had a uniform distribution between 0.5 and 25 nmol/L. Two replicate analyses of each serum or plasma sample were simultaneously done in the same assay. For RIA and CLIA, the intra-assay CVs were 5.85% and 6.70% and the interassay CVs 8.45% and 9.16%. For RIA and CLIA the progesterone values obtained with replicate analyses differed by as much as 11%-31% in 25% of samples. On average, the value of progCLIA was 85% of that of progRIA (95% CI 58%-112%, n = 110), with 88% of progCLIAs being lower than the progRIAs. This study shows that RIA and CLIA may yield replicate values that differ by as much as 11%-30% in about a quarter of samples analysed, necessitating replicate analyses if precise values are required. The study provides an equation by which to estimate progCLIA from progRIA.