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1.  The failure of flurofamide to control ureaplasma in bovine semen. 
The flurofamide sensitivities of 21 bovine ureaplasma isolates were determined using the metabolic inhibition method. The 21 isolates included seven each of vaginal, preputial and seminal origin. The minimum inhibitory concentrations of flurofamide ranged from 0.0125 to 0.2 meg/mL against a ureaplasma titer of 10(4) organisms/mL. The minimum lethal concentrations ranged from less than or equal to 0.1 to 3.2 mcg/mL. Flurofamide was then evaluated in a system comparable to the procedure for semen extension with respect to temperature, time and dilution. The compound was found to be ineffective in reducing ureaplasma numbers in this system at levels up to 1500 mcg/mL.
PMCID: PMC1255208  PMID: 3756683
2.  Studies on Mycoplasma mycoides subsp. mycoides (LC) in lambs and calves. 
Six cesarean-derived lambs were inoculated either with 4.5 X 10(4), 4.5 X 10(6) or 4.5 X 10(8) Mycoplasma mycoides subsp. mycoides intratracheally. One animal receiving the intermediate dose died four days post-inoculation, the two receiving the high dose died six days postinoculation, while one receiving the low dose died eight days postinoculation. The two surviving lambs were challenged on day 20 postinoculation with 1 X 10(8) organisms subcutaneously and 2 X 10(9) organisms intravenously. One animal died eight days following this challenge while the other survived and was killed. Six conventionally reared lambs challenged with 90 to 8500 organisms by intranasal and intraocular instillation failed to become infected. Three conventionally reared calves were each inoculated with 1 X 10(8) organisms by each of intratracheal, subcutaneous and intravenous routes. They were killed 20 days post-inoculation without having shown any clinical signs.
PMCID: PMC1236156  PMID: 3893663
3.  The effect of antibiotics against bovine mycoplasmas and ureaplasmas. 
A combination of lincomycin-spectinomycin-tylosin was tested against several strains of mycoplasmas and acholeplasmas as might be encountered in bovine semen and shown to be effective against them. This combination as well as minocin , rosaramicin, rosoxacin, tiamulin, gentamicin and declomycin were tested in vitro against 58 isolates of ureaplasma from the bovine urogenital tract. The lincomycin-spectinomycin-tylosin combination, minocin , rosaramicin, tiamulin and declomycin were quite active, while rosoxacin and gentamicin were much less active against the test strains.
PMCID: PMC1236032  PMID: 6232992
4.  Factors associated with the determination of antibiotic activity in bovine semen. 
Rosaramicin, an agent shown to be effective in vitro against ureaplasma of bovine origin was tested as an additive to bovine semen extender. Although some reduction in semen quality occurred it was still deemed satisfactory for use. In a test involving 41 cows inseminated once at estrus with rosaramicin-treated semen (162 mcg/mL) the nonreturn rate was 24% compared to a calculated average for this semen of 63% (n = 3310). The effect of centrifugation, time and temperature was examined in vitro using a combination of 150 mcg of lincomycin, 300 mcg of spectinomycin and 450 mcg of tylosin against ten strains of bovine ureaplasma. This combination has ureaplasmacidal activity and is suggested as an additive to semen extenders for the control of ureaplasma.
PMCID: PMC1235980  PMID: 6230144
5.  Ureaplasma serotypes associated with the bovine urogenital tract. 
One hundred and thirty-one ureaplasma isolates were tested using the immunoperoxidase system. Thirty-four were from semen, 34 from preputial washes of normal bulls and 63 were from vaginal swabs from herds experiencing infertility problems and/or vulvovaginitis. The serotypes from semen were T44 (12.1%), Bu2 (11.2%), D48 (2.8%), T315 (0.9%) and T288 (0.9%). Those from preputial washes were T44 (9.3%), Bu2 (8.4%), T288 (7.5%), D48 (0.9%) and T95 (0.9%). From vaginal swabs the serotypes were D48 (22.4%), Bu2 (10.3%), T45 (4.7%), T288 (3.8%) and T315 (1.9%).
PMCID: PMC1235978  PMID: 6365295
6.  A comparison of two enrichment and two plating media for the isolation of Salmonella sp. from broilers. 
Twenty duplicate cloacal swabs and the intestines of 98 broilers were cultured using Rappaport-Vassiliadis and tetrathionate as enrichment broths. These were plated to brilliant green and modified dulcitol brilliant green agars at one, two and seven days. Salmonellae were recovered with greater frequency from tetrathionate plated to modified dulcitol brilliant green than the other combinations.
PMCID: PMC1235956  PMID: 6640417
7.  Nongenital Mycoplasma Infections in Cattle 
The Canadian Veterinary Journal  1981;22(11):335-338.
A brief definition and classification of the organisms is followed by a history of their isolation and general role in disease. Diseases associated with various types of mycoplasma are discussed under respiratory tract, mastitis, arthritis and keratoconjunctivitis. Descriptions include methods of infection, clinical signs, lesions and prognosis.
PMCID: PMC1789992  PMID: 7337907
8.  A comparison of the in vitro activity of two antibiotics against bovine ureaplasmas. 
A comparison of the in vitro activity of rosaramicin and minocin against 52 bovine Ureaplasma sp. strains, 20 of which were isolated from semen, 23 from vaginal swabs, and nine from preputial washings, has shown that both antibiotics have good inhibitory action against the strains tested. Rosaramicin was ureaplasmacidal in most instances at, or close to the inhibitory level while for most strains studied a ureaplasmacidal level of minocin was not found.
PMCID: PMC1320133  PMID: 7260728
9.  Synovial immunoglobulin and antibody in vaccinated and nonvaccinated calves challenged with Mycoplasma bovis. 
Intravenous injection of Mycoplasma bovis produced in calves arthritis with synovial infiltration of lymphocytes, macrophages and neutrophils. Necrosis was observed focally around blood vessels. Joint spaces contained fibrinopurulent exudate. Parenterally vaccinated calves had a markedly reduced frequency of arthritic joints. Immunoglobulin classes and specific antibody in joint fluids were quantitatively less than in sera but significantly greater in arthritic than in normal joints. The possible mechanisms of induction of joint fluid antibody are discussed.
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PMCID: PMC1320127  PMID: 7272847
10.  Temperature sensitivity studies on selected strains on Mycoplasma gallisepticum. 
Mycoplasma gallisepticum (MG324), a tylosin resistant strain of low virulence, was compared with four other strains with respect to their survival at temperatures from 46.1 to 48.9 degrees C. MG324 was found to be more resistant than the other strains tested.
PMCID: PMC1277523  PMID: 1000381
11.  Necrotic enteritis in broiler chickens. III. Reproduction of the disease. 
Lesions typical of necrotic enteritis could be produced experimentally in from 11-26% of broiler chickens consuming feed containing approximately 10(7) Clostridium perfringens per gram. Highest mortality was produced using isolates from field cases of necrotic enteritis which were reisolated from experimental cases in the laboratory. Penicillin in the drinking water at 100,000 I.U./litre completely prevented mortality whereas chloramphenicol at 110 mg/litre delayed the onset and reduced the number of deaths compared to controls.
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PMCID: PMC1277518  PMID: 187291
12.  The recovery of Mycoplasmas from the genital tracts of bulls in artificial breeding units in Ontarïo. 
One hundred and thirty-two penial-preputial swabbings, 140 raw and 42 processed semen samples were cultured for mycoplasmas. Mycoplasma or acholeplasma were recovered from 87, 32 and one respectively, while ureaplasmas were recovered from 46, 34 and six respectively.
PMCID: PMC1277505  PMID: 1175080
13.  In vitro antimicrobial sensitivity of Mycoplasmas isolated from the bovine genital tract. 
The in vitro antimicrobial sensitivity of 14 mycoplasma and 13 ureaplasma strains isolated from the genital tracts of bulls was examined. It was found that at relatively low concentrations, tetracycline, declomycin and tylosin were lethal to both types of organisms. Lincospectin, berenil, streptomycin and erythromycin were lethal to mycoplasmas but were only inhibitory to the ureaplasma strains at the same concentrations. Polymyxin B and novobiocin were ineffective at the levels tested.
PMCID: PMC1277489  PMID: 169970
14.  Studies on the control of Mycoplasma gallisepticum in hatching eggs. 
Lincomycin-spectinomycin, while effective in eliminating Mycoplasma gallisepticum from hatching eggs when administered via the yolk sac, had a marked deleterious effect on hatch-ability when given by this route. On the other hand when lincomycin-spectinomycin was injected into the air cell there was a reduction in the level of experimental infection with an acceptable effect on hatchability.
PMCID: PMC1277452  PMID: 124623
15.  Studies with Radioactive Endotoxin I. Clearance of 51Cr-Labelled Endotoxin from the Blood of Calves 
The clearance of 51Cr-labelled Pseudomonas endotoxin from the blood was studied in calves in a nontolerant and in an endotoxin-tolerant state. Calves were rendered tolerant to the toxic effects of the endotoxin by four daily intravenous injections of endotoxin at the dose rate of 5 µg/kg body weight.
Clearance of a small amount of 51Cr-endotoxin from the blood of nontolerant calves was almost complete within three minutes of injection and was not significantly faster in tolerant calves. The lungs and liver were the major organs involved in clearance of endotoxin from the blood. The 51Cr label was slowly excreted by the kidneys. Neither platelets nor leukocytes were demonstrated to participate in endotoxin clearance in calves. 51CrCl3 was injected into control calves. Relative to the distribution and loss of labelled endotoxin, the 51CrCl3 was cleared slowly from the blood, was distributed uniformly throughout the body and was excreted rapidly.
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PMCID: PMC1319836  PMID: 4279754
16.  An Infection in Chickens with a Strain of Mycoplasma gallisepticum of Low Virulence 
A slow-spreading infection due to a strain of Mycoplasma gallisepticum was detected serologically in a flock which remained free of clinical symptoms. The strain was shown to be tylosin resistant. Serological studies indicated that vertical transmission occurred.
PMCID: PMC1319878  PMID: 4277360
17.  Studies of Escherichia coli Infection in Chickens 
The pathogenesis of infection with Escherichia coli was studied in chickens using live O78:K80 cells and a heat-labile chick lethal toxin. The results obtained were compared with those observed in field outbreaks. The common histological findings of subepicardial edema and congestion, focal necrosis in the spleen and focal necrosis, congestion, edema and accumulation of fibrin in the liver support an active role for chick lethal toxin in the pathogenesis of E. coli disease.
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PMCID: PMC1319989  PMID: 4274822
18.  Studies on the Chick-lethal Toxin of Escherichia coli 
A toxin which is lethal for two week old chicks has been recovered from strains of Escherichia coli O78:K80 of bovine and avian origin and from avian isolates of serogroups O2, O45 and O109. The toxin is heat-labile, antigenic, high in protein, inactivated by pronase, trypsin, amylase, and pancreatic lipase. The toxin may be precipitated by ammonium sulfate or TCA treatment from the supernatant obtained by repeated centrifugation of sonicated cells. Considerable purification has been obtained by column chromatography using Sepharose 6B.
PMCID: PMC1319795  PMID: 4270809
19.  Studies on the Serological and Immunological Response of Chickens to Endotoxin and Endotoxoid 
Chicks two, three and four weeks of age respond well serologically to endotoxin given intravenously, with the older chicks giving a better response. The induced immunity against live organism challenge produced by homologous endotoxin from Escherichia coli or Salmonella typhimurium is specific between these two organisms, however, cross-immunity occurs between E. coli 045 and E. coli 0109 and between Salmonella enteritidis and S. typhimcrium and further, endotoxins from different organisms may be combined to provide immunity against the homologous organisms. Endotoxoid administered to chicks rendered them more susceptible to live organism challenge for five days, following which some immunity developed.
PMCID: PMC1319638  PMID: 4259932
20.  The Transfer of Endotoxin Induced Immunity from Hens to Poults 
Turkey hens were vaccinated six times with Salmonella typhimurium endotoxin prior to and during their egg production cycle. The resultant poults possessed a significant degree of immunity to challenge with S. typhimurium.
PMCID: PMC1319659  PMID: 4258548
21.  Endotoxin Studies in Chicks: Effect of Lead Acetate 
Lead acetate administered intravenously in a mixture with endotoxin preparations potentiates the toxic effect of endotoxin for 14-21 day old meat strain chicks. A dose of 2.8 mg of lead acetate/100 g body weight is more effective with endotoxin than a dose of 2.5 mg; however, a dose of 3.0 mg or greater is toxic alone. The degree of potentiation appears to be at least 1000 fold and permits toxicity determinations using endotoxin levels ranging from 0.125 µg to 250 µg/chick. Endotoxin preparations made using NaCl, TCA or phenol-water extraction procedures, possessed toxic activity for chicks when tested by this method.
PMCID: PMC1319518  PMID: 4245789

Results 1-25 (27)