Reaction of fresh and frozen bull spermatozoa incubated with fresh and frozen bovine oviduct epithelial cells.

The hypothesis was tested that frozen bovine oviduct epithelial cells (BOEC) could provide a physiologic and standardized system for studying motility and acrosomal changes of fresh and frozen-thawed sperm. The BOEC were collected by lavage from cows and monolayers prepared from both fresh and frozen-thawed cells. Fresh and frozen semen processed from five bulls was extended in a modified Tyrode's medium and coincubated with both types of monolayers at 39 degrees C in 5% CO2 and 95% humidified air. After 5, 10 and 24 h of incubation, percentages of motile, progressively motile and acrosome-reacted unattached sperm were measured. The percentage of motile fresh sperm exceeded the motility of frozen sperm, and more fresh sperm attached to BOEC. More frozen sperm than fresh sperm were acrosome reacted. Fresh and frozen epithelial cells produced similar effects, except sperm motility was higher after 5 h of incubation with fresh BOEC. Thus, the convenient frozen-thawed coincubation protocol provides a practical in vitro system for studying capacitation and the acrosome reaction.

Granulocytic ehrlichiosis in dogs from North Carolina and Virginia.

Medical records of 3 dogs from North Carolina and 3 dogs from Virginia with ehrlichial morulae in circulating neutrophils were studied retrospectively. Two clinically distinct disease syndromes, including chronic, moderate to severe anemia (n = 3) and polyarthritis (n = 2) were associated with canine granulocytic ehrlichiosis (CGE) in these dogs. One dog was clinically healthy, and abnormalities were not detected during physical examination. Clinical signs were nonspecific and included fever, lethargy, anorexia, vomiting, and diarrhea. The most frequent laboratory abnormalities were normocytic normochromic nonregenerative anemia, moderate thrombocytopenia with large platelets, lymphopenia, and eosinopenia. Considerable variability was found in the serologic responses to Ehrlichia equi, Ehrlichia canis, and Ehrlichia chaffeensis antigens among the 5 dogs for which stored sera were available for indirect fluorescent antibody testing. Polymerase chain reaction amplification and sequencing of portions of the 16S rRNA gene from blood (collected in ethylenediaminetetraacetic acid) of 1 severely anemic dog (dog 3) and 1 polyarthritic dog (dog 4) resulted in DNA sequences nearly identical to the GenBank accessions for Ehrlichia ewingii. The DNA sequence from a 3rd dog (dog 5) was most similar to that of E. canis. Serologic or molecular results support the possibility of E. ewingii, E. equi, and E. canis coinfection or serologic cross-reactivity among canine granulocytic and monocytic Ehrlichia species in dogs from North Carolina and Virginia. Variability in response to tetracycline or doxycycline treatment was noted in these dogs, with more rapid resolution of signs in dogs with polyarthritis. We report the 1st cases of CGE in dogs from North Carolina and Virginia, including recognition of CGE in a healthy dog.

Development and survival after transfer of cow embryos cultured from 1-2-cells to morulae or blastocysts in rabbit oviducts or in a simple medium with bovine oviduct epithelial cells.

This study compares development of bovine 1-2-cell embryos in bovine oviduct epithelial cell co-culture (Group EC) with a glucose- and serum-free simple medium (CZB), or after surgical transfer to ligated oviducts of rabbits (Group RO). Embryos were surgically collected from superovulated donor cows 40-48 h after the beginning of oestrus and randomly distributed between the two groups. Embryos were cultured or incubated for 5 days. In Exp. 1, embryo quality scores and total numbers of cells in the two groups were compared. In Exp. 2, pairs of similarly treated morulae were transferred to each of 10 or 12 recipients in the Groups RO and EC, respectively. Total cell counts per embryo in both groups averaged 52 (P greater than 0.05), and the in-vitro culture system was equivalent to the rabbit oviducts in promoting embryo development for all characteristics measured. Embryo survival, as determined by ultrasound between Days 39 and 43 after oestrus, in 13 ideal recipients was 57% for embryos in Group EC and 58% for embryos Group RO. None of the 9 less desirable recipients was pregnant for either group. These results establish that cattle zygotes can develop to morulae in culture with bovine oviduct epithelial cells in a simple medium and can produce normal pregnancy rates.