Optimal timing for canine artificial insemination with frozen semen and parentage testing by microsatellite markers in superfecundency.

Parentage testing was performed in sixteen litters by canine artificial inseminations with frozen semen from different sires on Days 5 and 7 after the LH surge. It became apparent that only 25% of dams had superfecundation, but 43.8% of dams were whelped after insemination only on Day 5 after the LH surge and 31.3% of dams after insemination only on Day 7. Of the total 87 puppies, 46% were born after insemination on Day 5 after the LH surge and 54% after insemination on Day 7. This result strongly suggested that canine artificial insemination with frozen semen could be sufficiently successful also on Days 5 and 7 after the LH surge.

Development of a method of diagnosing ovarian disorders in sows and gilts using uterine ultrasonography.

In ultrasonographic diagnosis of ovarian disorders and the estrous cycle in sows, transverse observation of the uterus yielded more characteristic findings than observation of sagittal sections. Transverse ultrasonography revealed that the low progesterone (P) type uterus showed a round structure, while the high P type uterus showed a flattened structure. These results corresponded well with rectal palpation findings: the low P type uterus had a hard, pipe-like structure and the high P type a soft, balloon-like structure. For gilts, we employed a minimum convex type transrectal prostate probe that had an approximately 18 cm insertion handle. The images of the uterus obtained thereby were a similar to those obtained from sows. The above results suggest that it should be possible to diagnose and treat many ovarian disorders in sows and gilts based only on the ultrasonograhic findings. In short, ultrasonograhic findings of a round structure of the uterine wall might be an indication for PMSG (pregnant mare serum gonadotropin) treatment, while findings of a flattened structure might be an indication for PGF(2) (alpha) administration.

CD56 is expressed exclusively on CD3+ T lymphocytes in canine peripheral blood.

CD56+ cells in canine blood leukocytes were characterized by flow-cytometric analysis of peripheral blood of 30 healthy adult beagle-dogs (15 males and 15 non-pregnant females). In 19 of the 30 dogs, anti human CD56 antibody, Leu-19, reacted with 8.8-21.7% of peripheral blood lymphocytes. All CD56+ cells simultaneously expressed CD3 molecules on their surface. Further phenotypic analysis revealed that 50.6+/-13.1% of the CD56+ cells showed CD4-CD8+ phenotype and 43.7+/-10.1% showed CD4+CD8- phenotype. Expression intensity of CD56 on the CD4-CD8+CD56+ cells was significantly higher than that on CD4+CD8-CD56+ cells (P<0.001). These findings indicate that CD56, which is a neural cell adhesion molecule, is uniquely expressed on subsets of T lymphocytes in canine peripheral blood.