Prevalence of enteric zoonotic organisms in cats.

OBJECTIVE: To determine prevalence of enteric zoonotic organisms in cats in north-central Colorado. DESIGN: Prospective study. SAMPLE POPULATION: Serum and fecal samples from 87 cats with diarrhea, 106 cats without diarrhea, and 12 cats for which fecal consistency was unknown. PROCEDURES: Samples were obtained from client-owned cats and cats at a humane society shelter. Serum was assayed for feline leukemia virus antigen and antibodies against feline immunodeficiency virus, IgM antibodies against Toxoplasma gondii, and IgG antibodies against T gondii and Cryptosporidium parvum. Microscopic examination of unstained feces was performed after centrifugation in a zinc sulfate solution, thin fecal smears were stained with acid fast stain and examined for C parvum, and bacteriologic culture of feces was used to detect aerobic and anaerobic bacteria. RESULTS: Enteric zoonotic organisms were detected in feces from 27 of 206 (13.1%) cats and included C parvum (5.4%), Giardia spp (2.4%). Toxocara cati (3.9%), Salmonella enterica serotype Typhimurium (1.0%), and Campylobacter jejuni (1.0%); each organism was detected in samples from cats with and without diarrhea. Although differences between groups were not significant, a higher proportion of shelter cats (18.2%) had enteric zoonotic organisms than client-owned cats (10.1%). CONCLUSIONS AND CLINICAL RELEVANCE: Enteric zoonotic organisms were detected in feces of 13.1% of cats, suggesting that cats, particularly those in homes of immunocompromised humans, should be evaluated for enteric zoonotic organisms.

Development and testing of a bovine trichomoniasis vaccine.

Eighteen culled dairy cows were randomly allocated into 1 of 5 treatment groups. Six cows were vaccinated twice (2V), 21 days apart, 3 with whole cell (2WC) and 3 with fragmented cell membrane (2FC) containing 1 x 10(9)Trichomonas fetus organisms or protein equivalent in a commercial mineral oil adjuvant vaccine. Six more cows were vaccinated once (1V), 3 with whole cell (1WC) and 3 with fragmented cell vaccine (1FC), using the same vaccine, while 6 cows were used as the unvaccinated controls. All cows were challenged with 1 x 10(5) organisms 4 weeks after the second or the only vaccination. After challenge, cervico-vaginal mucus (CVM) samples were cultured for T . fetus weekly for 9 weeks. Whole cell vaccines were superior to fragmented cell vaccines, and both performed better than no vaccination for apparent elimination of trichomonad infections in dairy cows. In addition, 2V was superior to 1V, which, in turn, was superior to no vaccination. Furthermore, clearance time was reduced most by 2V and whole cell vaccination compared with 1V and fragmented cell vaccination. Clearance time was decreased significantly in all vaccinated cows compared with that in unvaccinated cows.

Testing of trichomoniasis vaccine in heifers mated to infected bulls.

This study was conducted to evaluate the effectiveness of a Trichomonas fetus vaccine to protect heifers from infection when bred to infected bulls. The vaccine consisted of a whole cell vaccine of T. fetus organisms stabilized in formaldehyde and adjuvanted in a mineral oil base. In the trial, fewer vaccinated heifers became infected than unvaccinated controls (69.4 vs 93.0%, respectively; P<0.08). The vaccinated heifers tended to clear the infections sooner than the controls (48.9 vs 68.5 days, respectively; P<0.10). The average number of days open was shorter in the vaccinated heifers than in the controls (33.2 vs 56.9 days, respectively; P<0.07). The first service conception rate was higher in the vaccinated heifers than in the controls (66.7 vs 33.3%, respectively; P<0.05). The number of services per conception in conceiving heifers was lower in vaccinated than in control heifers (1.44 vs 1.73, respectively; P<0.16). Cervicovaginal mucus (CVM) samples were collected every 14 days following first challenge (first service). On average, more CVM samples were positive for T. fetus for a longer period of time in the control than in the vaccinated heifers (3.9 vs 1.85 sampling periods, respectively; P<0.08). We concluded that, under the conditions of this trial, some protection to T. fetus was afforded by double vaccination with a whole cell vaccine. However, vaccination does not completely prevent heifers from developing infection.

Human cryptosporidiosis associated with an epizootic in calves.

An outbreak of human cryptosporidiosis occurred among previously healthy persons in a veterinary medical teaching hospital. Human illness began after admission of calves from a farm which had been experiencing an epizootic of neonatal diarrhea due to Cryptosporidium. The clinical syndrome in humans was characterized by watery diarrhea, abdominal cramping, flatulence, and headache. Cryptosporidiosis was confirmed by zinc sulfate flotation of fecal specimens in four persons, three of whom had been responsible for the care and treatment of infected calves. A fourth patient had washed her husband's soiled clothing and appeared to have been infected indirectly through fomite contamination. Among 112 persons surveyed, 26 (23.2 percent) had a diarrheal illness during the outbreak and nine met the case definition of a diarrheal illness lasting at least three days. These persons were more likely to have had contact with a calf with diarrhea than were 52 referents who did not become ill during the outbreak.

Parasitism in llamas.

Llamas in North America are infected with a number of helminth parasites, including: gastrointestinal nematodes, lungworms, meningeal worms, tapeworms, and flukes. Most of these helminths can be treated with the anthelmintic currently used to treat cattle and sheep. At least two protozoan parasites, coccidia and toxoplasma, have been reported in the llamas in North America. Coccidia can be controlled with the anticoccidial drugs used to control these organisms in other domestic animals. Toxoplasma has been reported uncommonly in llamas in North America and control is very difficult. Several external parasites occur in llamas in North America, including lice, mites, ticks, and the deer nasal bot. Except for the deer nasal bot, the other external parasites in the llama can be treated with pesticides approved for use in cattle.

Scrotal cestodiasis in a dog.

Scrotal cestodiasis was diagnosed from a surgical biopsy specimen from an 8-year-old Miniature Poodle. Peritoneal cestodiasis with secondary scrotal cestodiasis was suspected and could be explained by migration of the parasite along the vaginal tunics. Subsequent necropsy confirmed severe peritoneal cestodiasis due to Mesocestoides sp. It appears that scrotal cestodiasis may be an early indicator of peritoneal cestodiasis in male dogs and diagnostic pathologists and clinicians should be aware of this condition.

Control of venereal disease in infected herds.

Losses from trichomoniasis can be controlled by management and treatment strategies. The best strategy for control of campylobacteriosis is vaccination of cows and bulls with a competent vaccine.

Brain extract induces synaptic characteristics in the basal lamina of cultured myotubes.

The basal lamina (BL) that occupies the synaptic cleft of the skeletal neuromuscular junction is antigenically distinct from extrasynaptic muscle fiber BL, rich in acetylcholinesterase (AChE), and bears projections that form junctional folds in the postsynaptic membrane. We report here that these synapse-specific features of BL are all present at low levels in embryonic rat myotubes cultured without nerve, and that their levels are markedly increased by addition of a soluble extract from adult rat brain. Light and electron microscopic methods show that: (1) antibodies which bind preferentially to synaptic BL in vivo stain small, discrete patches of the myotube's BL; (2) AChE accumulates in patches on the myotube surface; and (3) myotube BL and membrane form invaginations that resemble junctional folds. Patches of BL that bear synaptic antigens, AChE, or folds usually overlie clusters of acetylcholine receptors in the plasma membrane. Myotubes treated with a brain extract bear 5 to 20 times more junctional folds and patches rich in acetylcholine receptors, synaptic BL antigens, and AChE than control myotubes. Together with a previous demonstration that electrical and/or contractile activity can modulate the amount and composition of myotube BL (Sanes, J.R., and J.C. Lawrence, Jr. (1983) Dev. Biol. 97: 123-136), these results suggest that nerves could regulate differentiation of muscle fiber BL by a combination of activity-dependent and -independent mechanisms.