Decreased reproductive effects from snakeweed (Gutierrezia microcephala) in Sprague-Dawley rats with increased dietary snakeweed consumption.

Sprague-Dawley rats have been used to study the pathogenesis and toxicokinetics of snakeweed (Gutierrezia microcephala and G sarothrae) toxicosis. Diets containing as little as 10% snakeweed (SW) will induce early embryonic toxicosis and abortion in Sprague-Dawley rats. The sc administration of safflower oil to inseminated female rats will provide protection/tolerance against SW embryotoxins. Two studies evaluated this embryotoxin protection. In the first study, an increase in daily consumption of SW resulted in increased embryo-fetal survival in the SW-containing diet+saline group from 0% in previous studies to 35%. In the second study, once again an increase in diet consumption was associated with 40% of the females in the SW-containing diet+saline group carrying litters to term.

Effects on reproduction in female offspring from Sprague-Dawley rats fed 10% snakeweed (Gutierrezia microcephala) throughout pregnancy and concurrent treatment with safflower oil.

Previous studies determined that safflower oil administration provided protection against the embryotoxicity seen following ingestion of 10% snakeweed (Gutierrezia microcephala) throughout pregnancy. Sixty-two young primiparous female rats born in those studies were paired with adult male Sprague-Dawley rats. After 4 d they were removed and carried their litters to term. Observations were made of the presence and extent of reproductive effects attributable to the 10% snakeweed exposure and differences in fecundity that were attributable to dosing with safflower oil or normal saline during the snakeweed exposure. Of the 62 rats, 50 carried litters to term and approximated the reproductive efficiency of normal primiparous Sprague-Dawley rats. There was no significant difference between the fecundity of females born to rats fed the 10% snakeweed and dosed with safflower oil, those born of rats fed snakeweed dosed with normal saline, or those fed a snakeweed-free diet and dosed with normal saline. Regardless of the diet or treatment administered, dams carrying their litters to parturition gave birth to healthy, normo-reproductive offspring. While the toxic principles in Gutierrezia species plants may act as estrogenic or anti-estrogenic compounds, they did not impair fertility in the female offspring of dosed rats.

Promethazine toxicity in a seven-month-old Doberman pinscher.

A 7-mo-old female Doberman Pinscher undergoing antibiotic treatment for tonsillitis was presented in near collapse with markedly low blood pressure, tachycardia, dilatation of pupils (non-responsive to light), and gastrointestinal distress. Since the owner could provide no history of significant toxin exposure, general supportive and non-specific toxicologic treatment protocols were initiated. Within 4 h marked improvement was observed. The owner's wife revealed that promethazine suppositories had been administered at a toxic level to control the vomition accompanying the tonsillitis.

Evaluation of tuberculin testing and measles prophylaxis procedures used in rhesus macaque quarantine/conditioning protocols.

Twenty-three of 103 adult rhesus macaques (Macaca mulatta) entering NIH holding facilities with no history of measles vaccination or infection, no titer to rubeola virus, a minimum of four negative results of intrapalpebral tuberculosis tests, and negative for Herpesvirus simiae and type D retroviruses were selected to evaluate the adequacy of commonly used quarantine/conditioning protocol procedures. One month after sensitization by subcutaneous inoculation with 100 mg of killed Mycobacterium tuberculosis in oil, an intrapalpebral tuberculosis test was administered in the right eyelid. All animals had reactions that ranged from grade II to grade V. The animals were then randomly allotted to three groups. Ten animals were inoculated with a rubeola-containing veterinary vaccine (VET), 10 were inoculated with a human measles vaccine routinely used in macaque quarantine procedures (HUM), and 3 were used as unvaccinated controls. Intradermal tuberculosis tests were administered in the left eyelid and the skin of the abdomen at vaccination (day 0), and subsequent abdominal skin tests were performed on days 5, 14, and 28. In addition, intrapalpebral tests were conducted on day 28. A higher response in the rubeola antibody enzyme-linked immunosorbent assay (ELISA) optical density (OD) results was observed in the VET-inoculated group at 14 days after inoculation. More significantly, two members of the HUM-vaccinated group had negative ELISA results after a single dose of vaccine. Three other members of the HUM-inoculated group had ELISA results that were near the OD cutoff value (0.15) and were retested by the measles indirect fluorescent antibody (IFA) test.(ABSTRACT TRUNCATED AT 250 WORDS)

Loperamide intoxication in a seven-week-old pup.

A 7-w-old Samoyed-cross pup was presented with central nervous system signs approximately 18 h following administration of the second of 2 doses of loperamide. Circling, vocalization, head pressing and unreactive pupils were present. There was no history of trauma. Improvement was seen shortly following administration of activated charcoal and 0.2 ml naloxone. Naloxone treatment was repeated at 2-h intervals over 12-h. Approximately 20 h following the initial clinical evaluation, the puppy was released to the owner for home care and observation.

Use of permethrin as a miticide in the African hedgehog (Atelerix albiventris).

The African hedgehog, Atelerix albiventris (also known as Erinaceous albiventris; 1,2) has recently undergone an increase in popularity as an exotic pet. This popularity (Beatrix Potter not withstanding) is due in part to the small size of the African hedgehog (adults are 4-6 in in length, weighing approximately 1 lb), its lack of hibernation or aestivation if reared under controlled light and temperature, and its general good nature and accommodation to handling.

Induced oral infection of the owl monkey (Aotus trivirgatus) with hepatitis A virus.

Several species of nonhuman primates have served as animal models for hepatitis A virus (HAV) infection and disease. This study was to determine the suitability of Aotus trivirgatus as an orally induced model for HAV infection and to reconfirm the owl monkey's susceptibility to the intravenous route of inoculation. Animals were inoculated, either orally or intravenously, with varying concentrations of PA-33 strain of HAV. Serum enzymes ALT, AST and GGTP levels were monitored and liver biopsies performed when values exceeded three standard deviations above individualized mean baseline values. All animals had postinoculation elevations of serum ALT and AST values, shed virus in their feces, and were seropositive to HAV by 60 days after inoculation. Eight of the ten postinoculation biopsy specimens had histologic lesions compatible with acute viral hepatitis. We conclude that the owl monkey is a useful and valuable model for the study of HAV disease.

Preparation of a prototype inactivated hepatitis A virus vaccine from infected cell cultures.

Studies were conducted on the preparation, inactivation, safety, and immunogenicity of a prototype hepatitis A virus vaccine prepared from infected cell cultures. BS-C-1 cells maintained in medium 199 without serum were infected with the HM175 strain of hepatitis A virus and harvested after 21-28 days. The harvested virus preparation contained 6.8-7.4 (log 10) cell culture infectious doses/ml. After exposure to 1:4,000 formalin at 35 C, the infectivity titer decreased 10(6)-fold in 30 hr at an exponential rate, although virus was detected in 5.0-ml vaccine samples for up to three days. Three separate vaccine lots elicited antibody in all the guinea pigs given three doses. Owl monkeys given three doses of vaccine did not have any evidence of HAV infection but developed antibodies identifiable by radioimmunoassay and serum neutralization tests. After either oral or intravenous challenge with at least 10(6) monkey infectious doses of a virulent field strain of hepatitis A virus, none of the vaccinated monkeys shed virus in their feces or had elevated serum levels of alanine aminotransferase. The findings suggest that an effective inactivated whole virus hepatitis A vaccine can be prepared from cell culture.