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1.
J Altern Complement Med ; 11(5): 793-8, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16296912

ABSTRACT

OBJECTIVE: The aim of this study was to assess health changes seen in routine homeopathic care for patients with a wide range of chronic conditions who were referred to a hospital outpatient department. DESIGN: This was an observational study of 6544 consecutive follow-up patients during a 6-year period. SETTING: Hospital outpatient unit within an acute National Health Service (NHS) Teaching Trust in the United Kingdom. PARTICIPANTS: Every patient attending the hospital outpatient unit for a follow-up appointment over the study period was included, commencing with their first follow-up attendance. MAIN OUTCOME MEASURE: Outcomes were based on scores on a 7-point Likert-type scale at the end of the consultation and were assessed as overall outcomes compared to the initial baseline assessments. RESULTS: A total of 6544 consecutive follow-up patients were given outcome scores. Of the patients 70.7% (n = 4627) reported positive health changes, with 50.7% (n = 3318) recording their improvement as better (+2) or much better (+3). CONCLUSIONS: Homeopathic intervention offered positive health changes to a substantial proportion of a large cohort of patients with a wide range of chronic diseases. Additional observational research, including studies using different designs, is necessary for further research development in homeopathy.


Subject(s)
Chronic Disease/epidemiology , Chronic Disease/therapy , Homeopathy/statistics & numerical data , Outpatient Clinics, Hospital/statistics & numerical data , Patient Satisfaction/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Health Status , Homeopathy/methods , Humans , Male , Middle Aged , Outcome Assessment, Health Care/statistics & numerical data , Surveys and Questionnaires , United Kingdom/epidemiology
2.
Zentralbl Veterinarmed B ; 41(7-8): 483-91, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7701861

ABSTRACT

The chemotactic role of eicosanoids in the pathogenesis of Pasteurella haemolytica infection was studied, using a tissue chamber infection model and pharmacological inhibitors of eicosanoid synthesis. Tissue chambers were implanted subcutaneously in 12 calves allotted to three treatment groups of equal size. At 45 days after implantation, calves received saline, dexamethasone, or phenylbutazone treatments, and tissue chambers in all animals were then inoculated with P. haemolytica. Chamber fluid samples were collected before inoculation and at 2, 6, 18, 40, and 90 h after inoculation. Bacterial counts, total leukocyte counts, pH and albumin concentrations in chamber fluids were determined using standard bacteriological and clinical pathological methods. Concentrations of eicosanoids and activity of interleukin-1 (IL-1) were measured by radioimmunoassay and a helper T cell bioassay, respectively. Concentrations of leukotriene B4 (LTB4), thromboxane B2 (TXB2), 6-keto-prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E2 (PGE2) increased markedly after inoculation. An inhibitory effect of dexamethasone on both LTB4 production and neutrophil influx, together with the temporal relationship between these two events, suggested that LTB4 served as a chemo-attractant. Activity-time profiles for IL-1 in chamber fluids were similar to those of the eicosanoids. Phenylbutazone and dexamethasone reduced the severity of the inflammatory responses as measured by lower concentrations of albumin and higher pH in treated versus control chamber fluids. The results of this study suggest that eicosanoid inflammatory mediators play an important chemotactic role in the pathogenesis of P. haemolytica infection.


Subject(s)
Chemotaxis, Leukocyte , Eicosanoids/physiology , Mannheimia haemolytica/immunology , Animals , Cattle , Dexamethasone/pharmacology , Diffusion Chambers, Culture , Eicosanoids/antagonists & inhibitors , Phenylbutazone/pharmacology , Random Allocation
3.
Res Vet Sci ; 54(3): 366-71, 1993 May.
Article in English | MEDLINE | ID: mdl-8337485

ABSTRACT

Distribution of erythromycin into subcutaneous tissue chambers was characterised pharmacokinetically and the effect of Pasteurella haemolytica infection on the extent of penetration was studied. Thermoplastic tissue chambers were implanted subcutaneously in the paralumbar fossae of six calves. Thirty-five days after implantation, the tissue chamber distribution of intramuscularly administered erythromycin (30 mg kg-1) was studied. Chambers were then inoculated with P haemolytica and the tissue chamber pharmacokinetics of erythromycin were again studied. Diffusion of erythromycin into tissue chambers was best described using a two-compartment model with tissue chambers representing a relatively inaccessible compartment. Despite changes in chamber fluid pH, the extent of erythromycin penetration into chambers was not affected by P haemolytica inoculation. Comparison of computer simulated concentration-time curves resulting from different routes of administration revealed that penetration of erythromycin into less accessible sites was more likely to be higher after intravenous administration than after intramuscular administration.


Subject(s)
Erythromycin/pharmacokinetics , Mannheimia haemolytica , Pasteurella Infections/metabolism , Animals , Cattle , Erythromycin/administration & dosage , Erythromycin/toxicity , Injections, Intramuscular , Mannheimia haemolytica/drug effects , Models, Biological , Pasteurella Infections/blood , Skin/metabolism , Time Factors , Tissue Distribution
4.
Am J Vet Res ; 54(1): 107-12, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8427453

ABSTRACT

Development of the rickettsia, Anaplasma marginale, in salivary glands of male Dermacentor andersoni exposed as nymphs or adult ticks, was studied indirectly by inoculation of susceptible calves with homogenates and directly by examination, using light microscopy and a DNA probe; some unfed ticks were incubated before tissues were collected. Salivary gland homogenates made from ticks in every treatment group caused anaplasmosis when injected into susceptible calves; prepatent periods decreased as the time that ticks had fed increased. Colonies of A marginale were seen only in salivary glands of ticks exposed as adults and not in those exposed as nymphs; the percentage of salivary gland acini infected in these ticks increased linearly with feeding time. However, the probe detected A marginale DNA in salivary glands of ticks from both groups; the amount of DNA detected increased as feeding time was extended. The amount of A marginale DNA appeared to remain constant in gut tissues, but to increase in salivary glands. Salivary glands of adult-infected male ticks that were incubated, but did not feed a second time, became infected with A marginale, and the pattern of infection of acini varied with incubation temperature. Development of A marginale in salivary glands appears to be coordinated with the tick feeding cycle; highest infection rate was observed in ticks exposed as adults.


Subject(s)
Anaplasma/growth & development , Arachnid Vectors/microbiology , Dermacentor/microbiology , Anaplasmosis/microbiology , Anaplasmosis/transmission , Animals , Cattle , Cattle Diseases/microbiology , Cattle Diseases/transmission , DNA Probes , DNA, Bacterial/genetics , Digestive System/microbiology , Male , Salivary Glands/microbiology , Temperature
5.
J Med Entomol ; 29(4): 657-68, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1495076

ABSTRACT

The persistence of Anaplasma marginale Theiler in male Dermacentor andersoni Stiles ticks exposed to the organism as adults was studied as the ticks were successively transferred to five susceptible calves. All calves fed upon by these ticks rapidly developed clinical anaplasmosis; incubation periods of infection ranged from 19 to 26 d and did not change significantly with successive feedings. Development of A. marginale in tick midgut and salivary glands was followed daily during tick feeding (total, 35 d) with light microscopy and DNA hybridization. With microscopy, A. marginale colonies persisted in midgut cells throughout the experiment. Large colonies were observed in gut muscle cells on days 8 through 35 and were the predominant infected cell type during this part of feeding. Colonies were seen in salivary gland acini from day 2 throughout the 35-d experiment. The DNA probe confirmed the presence of Anaplasma DNA in midgut and salivary glands throughout the experiment. Quantitative estimates of infection intensity in tissues of individual ticks approximated 10(7) initial body equivalents, confirming heavy infections. A marginale in midgut tissues decreased with feeding time, whereas the estimated number of organisms in salivary glands remained constant. These data demonstrate that D. andersoni males are efficient vectors of A. marginale and may be potential reservoirs of infection for ruminants for extended periods.


Subject(s)
Anaplasma/isolation & purification , Anaplasmosis/transmission , Arachnid Vectors/microbiology , Cattle Diseases/transmission , Dermacentor/microbiology , Anaplasma/genetics , Animals , Cattle , DNA, Bacterial/analysis , Male , Nucleic Acid Hybridization
6.
Am J Vet Res ; 53(5): 684-8, 1992 May.
Article in English | MEDLINE | ID: mdl-1524293

ABSTRACT

A subcutaneous soft tissue infection model in calves was used to study the in vivo response of Pasteurella haemolytica to erythromycin and dexamethasone. Two tissue chambers were implanted SC in each of 12 calves. At 45 days after implantation, all tissue chambers were inoculated with an erythromycin-sensitive strain of P haemolytica. Starting 24 hours after inoculation, calves were allotted to 4 groups of equal size and a 2 x 2-factorial arrangement of treatments was applied: 3 calves were given erythromycin (30 mg/kg of body weight, IM, for 5 days), 3 calves were given dexamethasone (0.05 mg/kg, IM, for 2 days), 3 calves were given erythromycin and dexamethasone, and the remaining calves served as nontreated controls. Chamber fluids were tested daily, and the response to treatment was measured. Neither erythromycin nor dexamethasone affected viability or growth of bacteria within tissue chambers. Dexamethasone had no effect on the influx of neutrophils into infected chambers. Despite repeated administration of a high dose of erythromycin and attainment of adequate concentration in serum, erythromycin concentration in chamber fluids did not exceed the minimal inhibitory concentration established in vitro. These results indicate that the clinical efficacy of erythromycin against P haemolytica sequestered in consolidated pneumonic lesions may not be well correlated with predictions based on serum pharmacokinetic and in vitro susceptibility data.


Subject(s)
Cattle Diseases/drug therapy , Dexamethasone/therapeutic use , Erythromycin/therapeutic use , Mannheimia haemolytica/drug effects , Pasteurella Infections/veterinary , Albumins/analysis , Animals , Cattle , Dexamethasone/administration & dosage , Dexamethasone/pharmacokinetics , Diffusion Chambers, Culture , Disease Models, Animal , Drug Therapy, Combination , Erythromycin/administration & dosage , Erythromycin/pharmacokinetics , Hydrogen-Ion Concentration , Injections, Intramuscular/veterinary , Leukocyte Count/veterinary , Neutrophils , Pasteurella Infections/drug therapy , Tissue Distribution
7.
Am J Vet Res ; 53(4): 499-507, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1586018

ABSTRACT

The development and transmission of Anaplasma marginale was studied in Dermacentor andersoni males. Laboratory-reared male D andersoni were allowed to feed for 7 days on a calf with ascending A marginale parasitemia. The ticks were then held in a humidity chamber for 7 days before being placed on 2 susceptible calves. Anaplasmosis developed in the calves after incubation periods of 24 and 26 days. Gut and salivary glands were collected from ticks on each day of the 23-day experiment and examined with light and electron microscopy. Colonies of A marginale were first observed in midgut epithelial cells on the sixth day of feeding on infected calves, with the highest density of colonies found in gut cells while ticks were between feeding periods. The first colonies contained 1 large dense organism that subsequently gave rise to many reticulated organisms. Initially, these smaller organisms were electron-lucent and then became electron-dense. On the fifth day after ticks were transferred to susceptible calves for feeding, A marginale colonies were found in muscle cells on the hemocoel side of the gut basement membrane. A final site for development of A marginale was the salivary glands. Colonies were first seen in acinar cells on the first day that ticks fed on susceptible calves, with the highest percentage of infected host cells observed on days 7 to 9 of that feeding. Organisms within these colonies were initially electron-lucent, but became electron-dense.


Subject(s)
Anaplasma/growth & development , Anaplasmosis/transmission , Arachnid Vectors/microbiology , Cattle Diseases/transmission , Dermacentor/microbiology , Anaplasma/ultrastructure , Animals , Arachnid Vectors/ultrastructure , Cattle , Dermacentor/ultrastructure , Male , Microscopy, Electron
8.
J Anim Sci ; 69(6): 2601-7, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1885373

ABSTRACT

A double L-shaped intestinal cannula was developed in an attempt to overcome problems observed previously with simple T-type cannulas. The cannula was constructed from cyclopolyvinyl chloride water pipe fittings. Construction materials were fairly rigid, but by connecting the split cannula pieces with elastic castration bands the cannula had some flexibility. Placing a short cone over the exposed cannula barrel reduced mechanical damage to the intestine. The double L cannula required a much smaller incision in the intestine during surgical insertion than a T-type cannula; it also simplified replacement. Construction is described; use and performance of the cannula has been satisfactory.


Subject(s)
Catheterization/veterinary , Cattle/surgery , Digestion , Intestines/surgery , Animals , Cattle/physiology , Duodenum/physiology , Duodenum/surgery , Eating , Female , Ileum/physiology , Ileum/surgery , Intestines/physiology , Male , Specimen Handling/veterinary , Weight Gain
9.
Am J Vet Res ; 51(8): 1292-4, 1990 Aug.
Article in English | MEDLINE | ID: mdl-2386330

ABSTRACT

The development of Anaplasma marginale was studied in Dermacentor andersoni nymphs after they had fed on a calf with ascending Anaplasma infection. Gut tissues were collected on day 4 of tick feeding, from newly replete (fed) nymphs and on postfeeding days (PFD) 5, 10, 15, 20, and were processed for light and electron microscopy to determine density of A marginale colonies. Homogenates of gut tissues were prepared from nymphs collected on the same days and inoculated into susceptible, splenectomized calves to test for infectivity. Anaplasma colonies were detected in gut cells on PFD 5, 10, 15, and 20. Although colony density appeared to be higher on PFD 10 and 15, differences were not significant. Nymphal type-1 colonies were detected in highest numbers on PFD 5 and 10, transitional colonies were seen in highest numbers at PFD 10 and 15, and nymphal type-2 colonies were observed only on PFD 20. Gut homogenates that were collected from ticks at 4 days of feeding, when newly replete, and on PFD 20 caused anaplasmosis when injected into susceptible calves, but homogenates made from ticks collected on PFD 5, 10, and 15 were not infective. The data indicate that of the colony types of A marginale that develop in replete nymphs, nymphal type-1 and transitional colonies may contain organisms that are not infective for cattle.


Subject(s)
Anaplasma/growth & development , Dermacentor/microbiology , Ticks/microbiology , Anaplasma/pathogenicity , Animals , Cattle , Colony Count, Microbial , Intestines/microbiology , Nymph/microbiology , Random Allocation , Time Factors , Virulence
10.
Am J Vet Res ; 51(1): 128-32, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2301812

ABSTRACT

The development of Anaplasma marginale in midgut epithelial cells was studied in feeding, transmitting adult Dermacentor andersoni ticks. Laboratory-reared ticks experimentally infected as nymphs were allowed to feed from 1 to 9 days on susceptible calves. Gut tissues from ticks were collected on each day they fed (total, 9 days) and were processed for light and transmission electron microscopy. Colonies of A marginale were abundant during the first 6 days of feeding, after which numbers decreased. Colonies were adherent to the basement membrane of gut cells early during feeding, with resultant flattening of the colonies. Colonies also were seen in muscle cells on the hemocoel side of the basement membrane. Morphologic features of A marginale within muscle cells varied and were similar to those observed in gut cells. In addition, however, a large reticulated form in the colonies was observed in muscle cells and appeared to give rise to small particles by budding. Development of A marginale in muscle cells appears to represent an intermediate site of development between those in gut and in salivary glands.


Subject(s)
Anaplasma/growth & development , Basement Membrane/ultrastructure , Dermacentor/microbiology , Ticks/microbiology , Anaplasmosis/microbiology , Animals , Female , Intestines/ultrastructure , Male , Microscopy, Electron , Nymph/microbiology
11.
Am J Vet Res ; 50(8): 1377-80, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2782719

ABSTRACT

Transstadial and transovarial transmission of Anaplasma marginale by Dermacentor variabilis were attempted with with ticks exposed to the organism once by feeding as larvae or nymphs, and twice by feeding as larvae and nymphs. Typical colonies of A marginale were in gut tissues of adults that were infected as larvae, larvae and nymphs, and as nymphs; repeated exposure of ticks did not appear to result in an increase in the number of colonies in the gut of subsequently molted adults nor did it affect severity of the clinical disease that developed in cattle they fed on. In contrast, colonies of A marginale were not found in the midgut epithelium of unfed nymphs exposed as larvae, even though companion nymphs transmitted the parasite, causing severe clinical anaplasmosis in susceptible calves. The organism was not transmitted transovarially by F1 larvae or nymphs from the groups exposed as parent larvae, nymphs, larvae and nymphs, and as adults. Some of the calves fed on by F1 progeny had a few erythrocytic marginale bodies that looked suspiciously like A marginale, as well as postchallenge exposure prepatent periods that were longer than other calves in the transovarial transmission study. Sera from these calves were tested for antibody to A marginale, using a highly sensitive immunoblot technique. Antibodies were not detected in any of the sera.


Subject(s)
Anaplasma/growth & development , Anaplasmosis/transmission , Arachnid Vectors/microbiology , Cattle Diseases/transmission , Dermacentor/microbiology , Ticks/microbiology , Animals , Arachnid Vectors/physiology , Cattle , Dermacentor/growth & development , Dermacentor/physiology , Female , Immunoblotting , Larva/microbiology , Male , Oviposition
12.
Am J Vet Res ; 49(7): 1010-3, 1988 Jul.
Article in English | MEDLINE | ID: mdl-2458688

ABSTRACT

On each day of feeding on susceptible calves, salivary glands obtained from groups of adult ticks that transmitted Anaplasma marginale were examined for A marginale colonies by use of light microscopy and transmission electron microscopy. On day 8 of feeding, salivary glands were examined, using fluorescein-labeled antibody and methyl green-pyronine stain. Use of fluorescein-labeled antibody consistently revealed small numbers of fluorescent foci in salivary gland acinar cells obtained from ticks that had fed for 8 days. Colonies of A marginale were seen by transmission electron microscopy only in salivary gland acini of male ticks; these colonies could not be identified, using light microscopy, in companion 1-micron plastic sections stained with Mallory stain. Methyl green-pyronine stain, used commonly to detect theilerial parasites in tick salivary glands, did not differentiate A marginale from cytoplasmic inclusions normally found in salivary gland acinar cells.


Subject(s)
Anaplasma/growth & development , Arachnid Vectors/microbiology , Dermacentor/microbiology , Ticks/microbiology , Anaplasma/ultrastructure , Anaplasmosis/transmission , Animals , Cattle , Female , Male , Microscopy, Electron , Salivary Glands/microbiology , Staining and Labeling
13.
Am J Vet Res ; 48(1): 96-9, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3826850

ABSTRACT

Three isolates of Anaplasma marginale--Virginia (VAM), Illinois (IAM), and Florida (FAM)--were compared for infectivity for Dermacentor andersoni. The isolates were selected, in part, because of a tail-like appendage that has been demonstrated in the VAM and IAM, but not in the FAM. Ticks were exposed to the isolates as nymphs either naturally by feeding on a calf with anaplasmosis or artificially by percutaneous inoculation with infected bovine erythrocytes. They were examined for infectivity after molting to the adult stage by determining their capability to transmit the disease to susceptible calves and by demonstrating colonies in tick gut sections. Only those ticks exposed to the VAM proved to be infected with A marginale; ticks naturally exposed and those artificially infected with this isolate transmitted the disease to susceptible calves. Colonies of A marginale were observed only in gut tissues of ticks naturally infected with VAM. The IAM (appendage present) and FAM (appendage absent) could not be found in ticks exposed by either method, indicating that factors other than the presence of inclusion appendages may be involved in infection of ticks by A marginale.


Subject(s)
Anaplasma/pathogenicity , Cattle Diseases/microbiology , Dermacentor/microbiology , Ticks/microbiology , Anaplasmosis/transmission , Animals , Cattle , Cattle Diseases/transmission
14.
Am J Vet Res ; 47(8): 1657-61, 1986 Aug.
Article in English | MEDLINE | ID: mdl-3752671

ABSTRACT

Colonies of Anaplasma marginale in midgut epithelial cells of experimentally infected Dermacentor andersoni were studied in adult ticks 1, 3, and 6 months old. Longevity of the parasite in ticks was assessed by evaluating its infectivity for splenectomized calves; calves were exposed by feeding ticks and by inoculation of tick gut homogenates. Longevity was also evaluated by determining size, type, and density of colonies in male and female ticks. The effect of incubation (2.5 days at 37 C) on colony density was also examined for ticks at each age period. All methods used to assess longevity of A marginale in ticks (tick transmission, calf inoculation, and histologic studies) indicated a decrease of the numbers of organisms in 6-month-old ticks. Furthermore, when tick gut homogenates from 6-month-old nonincubated ticks were not infectious for susceptible calves, incubation of ticks before dissection restored infectivity of homogenates. Colonies of A marginale were detected in gut tissues of 6-month-old ticks that were not infective; therefore, infectivity of ticks could not be confirmed merely by presence of A marginale colonies.


Subject(s)
Anaplasma/growth & development , Dermacentor/microbiology , Ticks/microbiology , Anaplasma/classification , Anaplasmosis/microbiology , Animals , Cattle , Digestive System/microbiology , Epithelium/microbiology , Female , Male
15.
Am J Vet Res ; 47(8): 1662-4, 1986 Aug.
Article in English | MEDLINE | ID: mdl-3752672

ABSTRACT

Newly replete nymphal Dermacentor andersoni (principals) were percutaneously exposed to Anaplasma marginale by injection of either intact or lysed infected bovine erythrocytes. Control nymphs were fed on calves with anaplasmosis. The subsequently molted adults were examined for infection by light microscopy, and companion ticks were tested for infectivity by allowing them to feed on susceptible calves. When they fed as adults, both control ticks and percutaneously inoculated principals transmitted A marginale to susceptible calves. Prepatent periods in calves varied according to the method by which nymphs were infected. Colonies of A marginale were found in all ticks that acquired infection by feeding, but colonies were not observed in any ticks exposed percutaneously. The possible developmental cycle of A marginale in artificially infected ticks is discussed.


Subject(s)
Anaplasma/growth & development , Anaplasmosis/transmission , Dermacentor/microbiology , Ticks/microbiology , Animals , Cattle , Dermacentor/growth & development , Digestive System/microbiology , Erythrocytes/microbiology , Female
17.
Infect Immun ; 50(3): 881-6, 1985 Dec.
Article in English | MEDLINE | ID: mdl-2415457

ABSTRACT

Epitopes of major surface proteins of the intraerythrocytic cattle stage of Anaplasma marginale were demonstrated in the midgut stage of the organism within the infective tick host Dermacentor andersoni. These proteins were common to all A. marginale isolates tested and at all stages of parasitemia. Sera from cattle immunized with the tick midgut stage of A. marginale immunoprecipitated multiple-erythrocyte-stage proteins, as demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The major proteins recognized (primarily greater than 14 and less than 200 kilodaltons [kDa]) included two major-erythrocyte-stage surface proteins of 36 and 105 kDa molecular size. To confirm the presence of common tick and erythrocyte A. marginale antigens with the immunized cattle sera, we purified the 36-kDa erythrocyte-stage protein by monoclonal immunoaffinity chromatography and developed an enzyme-linked immunosorbent assay based on the purified protein. All sera from cattle immunized with tick-stage A. marginale and cattle infected with various isolates of A. marginale developed antibodies to the 36-kDa protein. The potential immunoprophylactic, diagnostic, and epidemiologic value of the major epitopes common to both the invertebrate and mammalian stages of A. marginale, especially the 36-kDa protein, is discussed.


Subject(s)
Anaplasma/immunology , Antigens, Bacterial/analysis , Cattle/microbiology , Epitopes/analysis , Ticks/microbiology , Animals , Antibodies, Monoclonal/analysis , Chemical Precipitation , Enzyme-Linked Immunosorbent Assay , Iodine Radioisotopes , Radioimmunoassay , Sulfur Radioisotopes
18.
Am J Vet Res ; 46(8): 1762-4, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4037505

ABSTRACT

Infection with Brucella ovis was established by conjunctival instillation in 8 male white-tailed deer (Odocoileus virginianus). Infection was transient in young bucks, but persisted in bucks that were mature when inoculated. The deer were euthanatized and necropsied at various intervals after inoculation. Brucella ovis was recovered from a mature buck at necropsy on postinoculation day 429. Four deer had gross lesions and histopathologic changes of the epididymides. A mature noninfected buck confined for 7 months with an infected buck acquired infection and developed epididymal lesions.


Subject(s)
Brucellosis/veterinary , Deer , Animals , Brucella/isolation & purification , Brucella/pathogenicity , Brucellosis/immunology , Brucellosis/pathology , Disease Susceptibility , Epididymis/microbiology , Epididymis/pathology , Male , Semen/microbiology , Species Specificity , Testis/pathology
19.
Am J Vet Res ; 46(7): 1565-7, 1985 Jul.
Article in English | MEDLINE | ID: mdl-4026042

ABSTRACT

Laboratory-reared Dermacentor andersoni ticks experimentally infected as nymphs with Anaplasma marginale were allowed to feed as adults from 1 to 9 days on susceptible, splenectomized calves to determine when, during feeding, the hematozoan was transmitted from ticks to cattle. In experiment 1, ticks were allowed to feed on calves for 1, 2, 3, 4, 5, or 6 days and anaplasmosis did not result. The same calves were used for experiment 2, and ticks were allowed to feed for 1, 3, 6, 7, 8, or 9 days and anaplasmosis occurred in all calves on which ticks fed for greater than or equal to 6 days. In 2 trials in experiment 3, ticks were allowed to feed on calves for 1 to 9 days. Anaplasmosis developed only in calves on which ticks fed for 7, 8, or 9 days. The prepatent periods shortened with longer tick feeding, and linear regression analysis of combined prepatent periods of both trials of experiment 3 indicated a significant (P = 0.05) slope with an estimated daily decrease of 7.75 days from day 7 to 9 of feeding. There was no apparent correlation between length of tick feeding and severity of clinical signs in those calves that developed anaplasmosis. Seemingly, A marginale can be transmitted to cattle by adult D andersoni ticks no earlier than the 6th or 7th day of feeding.


Subject(s)
Anaplasmosis/transmission , Arachnid Vectors , Cattle Diseases/transmission , Dermacentor/microbiology , Ticks/microbiology , Animals , Blood , Cattle , Dermacentor/physiology , Feeding Behavior , Female , Male
20.
Am J Vet Res ; 45(9): 1800-7, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6497136

ABSTRACT

Dermacentor andersoni nymphs were placed in stockinettes and allowed to feed on a splenectomized calf with experimentally induced anaplasmosis when the parasitemia was 3%-5%. Nymphs were selected on each of the 6 days of feeding and every 5 days from repletion through molting to the adult stage (25 days postrepletion); they were killed and midgut tissues were processed and examined by light and electron microscopies. No stages of A marginale were seen in tissues of feeding ticks. Visualization of individual components of gut contents was difficult owing to presence of the concentrated, electrondense blood meal containing hemoglobin. Inclusion appendages were observed in midgut tissues of nymphs at 5 and 10 days postrepletion, but not at 20 or 25 days. The morphology of the appendages was similar to that described for inclusion appendages commonly associated with anaplasmal inclusions in bovine erythrocytes. Some appendages were free in the lumen of the midgut and occurred either alone or with clusters of small vesicular particles. Occasionally, initial bodies like those generally found in bovine erythrocytes were seen with the appendage, but most of them were swollen and appeared to be degenerating. Frequently, inclusion appendages were observed attached to the luminal surface of the midgut cell membrane by a blunt, electron-dense attachment complex. The attachment of the appendage appeared to be extracellular, with the pointed end extending into the lumen. Often, small particles were observed immediately across the cell membrane from where the appendages were attached; the small particles appeared to be generated from the appendage itself and to have passed through the membrane of the midgut cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Anaplasma/ultrastructure , Dermacentor/microbiology , Ticks/microbiology , Anaplasma/physiology , Animals , Cattle , Dermacentor/ultrastructure , Erythrocytes/microbiology , Microscopy, Electron , Nymph/microbiology , Nymph/ultrastructure
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