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Semen and blood samples from 154 rams from two Montana range flocks (Flock A, vaccinated for Brucella ovis ; Flock B, nonvaccinated) were evaluated to determine the relationship between Brucella ovis (B. ovis ) semen culture results and various semen and blood parameters. All rams utilized in this study exhibited no palpable ram epididymitis lesions. Thirteen and 25.6% of the rams tested in Flocks A and B, respectively, had positive B. ovis semen cultures. Only age of ram and ram condition scores differed (P<0.05) between flocks. No flock by semen culture interactions were detected (P>0.05) for any of the parameters evaluated. Age of ram, ram condition score, and spermatozoa rate from forward movement were unrelated (P>0.05) to B. ovis culture results. Rams with positive B. ovis semen cultures had lower sperm motility (P<0.05), higher percentage of abnormal spermatozoa cells (P<0.05), higher percentage of spermatozoa head abnormalities (P<0.01), lower percentage of live-normal cells (P<0.05), higher incidence of white blood cells in semen (P<0.01) and higher complement fixation (CF) titers (P<0.01).

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For the purpose of developing and improving vaccines to protect cattle against bovine genital campylobacteriosis, the interaction of vaccine dose, strain(s) of Campylobacter fetus, and type of adjuvant was studied in the pregnant guinea pig model. Five strains of C fetus were used in the preparation of 20 monovalent vaccines containing various doses of bacteria (0.1 mg to 20 mg, dry weight) in Freund incomplete adjuvant, Freund complete adjuvant, or aluminum hydroxide gel adjuvant. Vaccinal protection against homologous or heterologous challenge exposure with viable C fetus strains was measured in terms of infection, abortion, and serum antibody titers. Major emphasis in the study was placed on vaccines containing highly virulent C fetus subsp venerealis strains (1289 and 17761) that possess most of the heat-labile K antigens that have been identified. Vaccines incorporating strain 1289 provided greater protection against abortion than did strain 17761 vaccines (difference, 29%; P less than 0.05). A positive (P = 0.61) correlation was seen between protection from abortion and strain 1289 serum antibody titer. When the titer was greater than or equal to 4, protection was greater than 80%, whereas abortion was associated with a serum antibody titer less than or equal to 2. In an experiment comparing 2-mg vs 20-mg doses of strain 17761 prepared in aluminum hydroxide gel adjuvant, protection against challenge exposure with the heterologous strain 23 was significantly (P less than 0.05) lower than that against challenge exposure with the homologous strain at the 2-mg dose.(ABSTRACT TRUNCATED AT 250 WORDS)

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The MICs of triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) and the effect on swarming were determined for 35 isolates of Proteus mirabilis and 7 isolates of P. vulgaris of animal origin. Both species were susceptible to the antimicrobial agent, and growth of all but one isolate was inhibited by less than 1 microgram/ml in broth and on agar without blood. Swarming was inhibited at triclosan concentrations two- to fourfold less than the MICs. Higher concentrations were required with blood agar than with plain agar for inhibition of growth and swarming.

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Bulk-cell yields were obtained from 4 Campylobacter spp incubated aerobically without the use of a special atmosphere. A button agglutination test was developed for quantitation of blood serum antibodies against C fetus subsp venerealis, C fetus subsp fetus, C jejuni, and "C hyointestinalis." The test was sensitive, and different individuals reading it usually attained the same titers. Cells of C fetus subsp venerealis, C fetus subsp fetus, and "C hyointestinalis" grown aerobically in broth made satisfactory antigens for the button test, but some cell pools of C jejuni had a tendency to autoagglutinate. Cells of C jejuni grown on blood agar had less tendency to autoagglutinate.

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Nine strains of "Campylobacter fecalis" were compared with two references strains of C. sputorum subsp. bubulus considering DNA base composition and DNA-DNA-hybridization. The results showed that the two taxa could not be separated by these methods, their mol%(G+C) being 31-32 and DNA relatedness 79% or more. It is suggested that the catalase-positive "Campylobacter fecalis" should be regarded as a subspecies of the catalase-negative C. sputorum.

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A selective medium was developed for the isolation of Bacteroides fragilis directly from ovine and bovine fecal samples. The medium (tryptose blood agar plus polymyxin B, triclosan (Irgasan), novobiocin, and nalidixic acid) permitted growth of B. fragilis and several other species of Bacteroides but inhibited growth of most other intestinal bacteria.

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Fecal specimens from 136 healthy beef calves (1 day to 12 weeks of age) were examined for the presence of infectious agents known to cause enteric disease in calves. The calves were selected from 22 herds in which all calves were free of clinically apparent enteric disease. Salmonella sp, enterotoxigenic Escherichia coli, Cryptosporidium, and coronavirus were not detected in any of the calves. Three calves were infected with rotavirus and 1 calf was infected with Yersinia enterocolitica. Campylobacter-like bacteria were isolated from 50 of 130 calves, with 36 of the calves positive for C jejuni. Seemingly, clinically normal calves may be infected more often with enterotoxigenic E coli, Cryptosporidium, coronavirus, or rotavirus in herds in which some calves have enteric disease than in herds free of major enteric disease. Campylobacter jejuni was well adapted to the bovine host and was of similar prevalence in diarrheal and nondiarrheal calves. The K99 positive, nonenterotoxigenic E coli was isolated from the feces of 16 healthy calves. Information in addition to the presence of K99 antigen is useful when diagnosing enterotoxic colibacillosis in calves.

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Bacteroides fragilis with enterotoxin-like activity (BFEL) was isolated from the feces of 24- to 48-h-old lambs with acute diarrheal disease on three different sheep ranches in the Northern Rocky Mountain region of the United States. The lamb intestinal loop test was used to enrich for the bacterium before its initial isolation. Pure cultures of B. fragilis from the feces of diarrheic lambs caused fluid accumulation in five of five lamb intestinal loop tests and in three of three calf intestinal loop tests. Two different serogroups of BFEL were found in diarrheic lambs, and a third serogroups was found in the feces of a diarrheic ewe. Enteric disease characterized by diarrhea, depression, and inappetence occurred in three of eight newborn, colostrum-fed lambs after oral challenge inoculation with viable BFEL. One of the three lambs died 32 h after challenge. Clinical signs of disease were similar to those observed in the naturally occurring disease. B. fragilis is an obligately anaerobic bacterium found in the intestinal tract of most animals and humans. It is a serious cause of extraintestinal infection in humans. The bacterium has not been reported to cause fluid accumulation in the intestine or to cause diarrhea in any species of animal.

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Fecal samples from 127 diarrheic and 3 healthy beef calves, representing 25 herds with enteric disease, were cultured for Campylobacter, using filtration and a selective medium. Campylobacter fetus subsp jejuni (CFJ) was isolated from 51 (40%) of the diarrheic calves representing 14 (56%) herds and from the 3 clinically healthy calves (1 each in 3 of these 14 herds). Campylobacter fetus subsp intestinalis was not isolated from the calves. Fecal samples from 36 diarrheic and 20 healthy lambs representing 8 ranches were negative for Campylobacter. Isolates of CFJ from aborted lambs and from the feces of calves, ducks, dogs, and persons, appeared identical from the standpoint of morphology and physiologic reactions. In 12 calves and 5 lambs fed cultures, CFJ became colonized. Three of the calves developed diarrhea, but 2 were compromised by other disorders at the time of challenge exposure. None of the other calves or lambs developed diarrhea, but 10 of the calves and all of the lambs had frank or occult blood in the feces. Lamb intestinal loops were not distended by cultures of CFJ, but some cultures caused pathologic changes in the loops. None of 10 cultures of CFJ tested caused diarrhea in infant mice. Campylobacter fetus subsp jejuni is apparently capable of causing irritation and pathologic changes in the intestinal tract of young calves and lambs. Additional studies are needed to assess the role of CFJ in spontaneous enteric disease of calves.

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These studies were designed to identify the antigens of Campylobacter fetus subsp fetus that elicit vaccinal immunity. Heifers were vaccinated subcutaneously twice (42 days between vaccinations) with bacterins containing K, O, and H antigens (group A), O and H antigens (group B), or O antigen (group C) of the challenge strain. Five heifers were not vaccinated and served as controls (group D). Two weeks after heifers were given the second vaccination, the immunity of all heifers was challenge exposed by inoculating a live culture against the cervical os. Cervicovaginal mucus samples were examined by microbiological culture technique, using a selective medium, at 7- and 14-day intervals after challenge exposure. One of the six vaccinated heifers in group A became infected, as did all vaccinated heifers in groups B and C and the controls (group D). Only heifers vaccinated with bacterin containing K antigen were resistant to experimental infection with C fetus subsp fetus (P = 0.0002). Humoral antibody responses to whole-cell antigen were monitored, using a tube agglutination test, with and without treatment of the serum with 2-mercaptoethanol. An anamnestic antibody response of 2-mercaptoethanol-resistant antibody was detected in heifers in both groups A and B. An agglutination test (IGGK) was developed to measure immunoglobulin G directed against the K antigen and was used in an attempt to correlate agglutination titers with the immunity to challenge exposure. With the IGGK test, the serum agglutination titers of heifers in group A were significantly higher (P less than 0.0001) than those of heifers in group B. The results of these studies indicate that K antigen of C fetus subsp fetus elicits vaccinal immunity and that a direct correlation exists between the IGGK test and immunity on a group basis.

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Thirteen heifers (group A) given a booster vaccination with Campylobacter fetus 4 1/2 months before breeding to bulls infected with the homologous strain had a pregnancy rate of 54%, compared with a pregnancy rate of 92% for 12 heifers (group B) given a booster vaccination 10 days before the 63-day breeding period began. None of 7 nonvaccinated heifers became pregnant, and all remained infected for at least 136 days. All three groups of heifers were bred by the same infected bulls. Nine of the heifers in group A, but none of the heifers in group B, became infected during the first estrus. Blood serum agglutination titers peaked 2 weeks after the first vaccination but decreased to prevaccination titers 6 weeks later. Titers more than double those produced by one vaccination peaked between 2 and 3 weeks after booster vaccination but in most heifers had decreased to low titers 7 weeks later. When the breeding period began, the median antibody titer was 640 for heifers in group A and 10, 240 for heifers in group B. Indications of an anamnestic response due to natural challenge were not found in any of the 9 infected heifers in group A when serum titers were determined 27 and 34 days after breeding began. Therefore, it appears that in many heifers and cows, only the antibodies produced by booster vaccination will be available to provide protection. Inasmuch as vaccinal antibody titers decrease rapidly, it was concluded that booster vaccinations should be given approximately 10 days before breeding so that titers will be high during the breeding period.

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A method was developed for making viable counts of Campylobacter fetus (Vibrio fetus) in tube cultures using a medium containing alkaline hematin and incubation in a carbon dioxide incubator.

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Severe enteric colibacillosis, characterized by profuse watery diarrhea, dehydration, apathy, hypothermia, and inability to stand, was produced in seven of eight newborn, colostrum-fed calves from nonvaccinated dams after oral challenge of calves with 10(11) viable cells of Escherichia coli strain B44. Twenty-nine of 32 calves from dams vaccinated with various preparations of E. coli strain B44 were protected against severe enteric colibacillosis after oral challenge. Calves were protected if the dams received two subcutaneous vaccinations prior to calving. Calves also were protected if the dams were given a homologous vaccine of live or killed whole cells or a broth culture supernatant vaccine via the subcutaneous and intramammary routes 1 year earlier. Nineteen of the 29 protected calves had a transient diarrhea.

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