Experimental transmission of rabbit syphilis

Rabbit syphilis was experimentally transmitted from clinical cases to healthy rabbits. The purpose was to evaluate changes in RPR titers during the course of infection and to detect the pathogenic organism. Two of three littermate rabbits were inoculated topically. One rabbit became symptomatic, with typical clinical signs on its genitalia about 8 weeks after inoculation and a marked rise in RPR titers, another remained asymptomatic with a moderate rise in titers, and the control rabbit remained negative. These results supported the specific relationship between clinical signs and RPR titers. Histopathological examination of the skin lesion from the symptomatic rabbit revealed spirochetes.     

Ability of CD8+ T cell anti-feline immunodeficiency virus (FIV) activity and FIV proviral DNA load in mononuclear cells in FIV-infected cats

We investigated the relationship between CD8+ T cell anti-feline immunodeficiency virus (FIV) activity and FIV proviral DNA load integrated in mononuclear cells. The anti-FIV activity and the proviral DNA load were correlated, and the number of proviral DNA copies was high in cats with decreased anti-FIV activity. Particularly, no anti-FIV activity was detected in the cats staged as having an acquired immunodeficiency syndrome (AIDS)-related complex or AIDS, and the number of proviral DNA copies was obviously increased compared to those in the cats in the asymptomatic stage. These results suggest that decreased anti-FIV activity destroys the control of in vivo FIV replication, which leads to an increased proviral DNA load with the progression of the clinical stage of disease.     

Melanocytic matricoma in a dog

We report a tumor that developed at the root of the tail in a male, 2-year-old Shih Tzu dog. Histologically, the tumor consisted of basaloid epithelial cells, with shadow cells and neoplastic melanocyte proliferation. Immunohistochemically, epithelial components were positive for keratin/cytokeratin but basaloid cells were negative. Mononuclear or multinuclear melanocytes were positive for vimentin, S-100 protein, and HMB-45. In conclusion, this dog was diagnosed with canine melanocytic matricoma on the basis of the similarity of the histologic and immunohistochemical features in humans, and it may be the first case in an animal.     

Morphological, histological, and ultrastructural studies of the ovary of the cattle-tick Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae)

This study presents the morphology of the ovary, as well as the dynamics of the vitellogenesis process in oocytes of the cattle-tick Boophilus microplus. The ovary of these individuals is of the panoistic type; therefore, it lacks nurse cells. This organ consists of a single tubular structure, continuous, and composed of a lumen delimitated by a wall of small epithelial cells with rounded nuclei. In this tick species, the oocytes were classified into six stages varying from I to VI and according to: cytoplasm appearance and presence of the germ vesicle, yolk granules, and chorion. Oocytes of various sizes and at different developmental stages remain attached to the ovary through a cellular pedicel until completing stage V. Afterwards, they are liberated into the lumen and from there to the exterior. Some oocytes (classified as type VI) showed an atypical appearance indicating that some of the cellular components would be undergoing a degenerative process and/or reabsorption.     

Characteristics of Staphylococcus aureus isolated from lesions of horses.

Seventy-six Staphylococcus aureus strains isolated from various lesions of horses were characterized. All of the 76 strains were identified as biotypes B (38.2%) and C (61.8%). Of 55 strains tested, 42 (76.4%) were differentiated into 7 coagulase types. Coagulase types V and VII were predominant in the metritis strains. Coagulase type II was found most frequently in the strains from phlegmon, dermatitis, sinusitis, empyema sinus, and nasal catarrh. Forty-two (55.3%) of the 76 strains were differentiated into 24 phage patterns. Twenty (58.8%) of 34 typable strains from metritis were lysed by the human group I phage 52, and group II phages 3A, 3C, 55 and 71. Forty-five (59.2%) of the 76 strains were resistant to 1 or more of 6 antibiotics. Strains resistant to penicillin G, irrespective of source, were most frequent (95.6%). Forty (93.0%) of 43 strains resistant to penicillin G alone or in combination with other antibiotics produced beta-lactamase. Only 8 (10.5%) of the 76 strains produced enterotoxins A (n = 2), B (n = 1) or C (n = 5), and they all were isolated from metritis. Only 1 strain isolated from phlegmon and 2 from metritis produced exfoliative toxin (ET) and toxic shock syndrome toxin-1 (TSST-1), respectively. The latter 2 strains also produced enterotoxin C. The results of the present study showed the first evidence of the presence of both ET- and TSST-1-producing S. aureus isolated from horses.     

Cloning of bovine MAIL and its mRNA expression in white blood cells of Holstein cows

Molecule possessing ankyrin-repeats induced by lipopolysaccharide (MAIL) is known as an IkappaB protein induced after administration of bacterial lipopolysaccharide (LPS) to mice. In the present study, we cloned bovine MAIL cDNA and examined its mRNA expression in white blood cells isolated from Holstein cows. Bovine MAIL had more than 80% amino acid identities with murine and human MAILs, highly conserved ankyrin-repeat motifs and PEST-like sequences. Bovine MAIL mRNA was undetectable in isolated peripheral white blood cells, but rapidly induced (<1h) after stimulation by LPS and lipid A in vitro in a dose-dependent manner. The lipid A-induced MAIL mRNA expression was found in polymorphonuclear cells, monocytes/macrophages and total lymphocytes, but not in T-lymphocytes. MAIL mRNA was also induced in vivo in peripheral blood leukocytes of cows after intramammary injection of Escherichia coli derived from coliform mastitis. Thus, bovine MAIL, as rodent MAILs, is induced by inflammatory stimuli in specific immune cells in vitro and in vivo, suggesting a role in inflammatory responses to bacterial infection in cattle.