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991.
R. H. Dwinger P. Rawlings P. Jeannin A. S. Grieve 《Tropical animal health and production》1990,22(1):37-43
Summary The transmissibility of trypanosome infection to N'Dama cattle by tsetse flies caught in the field was examined. Wild-caughtGlossina palpalis gambiensis were transferred singly into small numbered cages and allowed to feed on 14 uninfected N'Dama cattle. Following a completed feed the tsetse were dissected and infection in the proboscis, the salivary glands and the gut was recorded. Each animal was bitten by a number of tsetse ranging from five up to 64 flies. Following dissection of the tsetse flies, seven of the cattle were found to have been bitten by a single infected tsetse, five by two, while the remaining two were each fed upon by three infected tsetse. The tsetse were harbouring eitherTrypanosoma vivax or a trypanosome species belonging to theNannomonas subgenus or both species. The experimental animals were monitored daily over a period of three months for the appearance of trypanosomes in the blood and for antibodies in their sera. Other parameters such as body temperature, local skin reactions, packed red cell volume and weight changes were also measured. Trypanosomes were first detected eight days after the infective bite. Only five of the 14 cattle became infected, of which three had been exposed to a single infected tsetse fly.Trypanosoma vivax was detected in one animal,Trypanosoma congolense in two cattle and mixed infections of both species in the remaining two animals. These findings show that N'Dama cattle can become infected with trypanosomes through the bite of a single infected tsetse fly under field conditions. However, only five (possibly eight) of the 23 infected tsetse were able to transmit the parasites successfully.
Infeccion Experimental De Ganado N'Dama Con Tripanosomas UsandoGlossina Palpalis Gambiensis Atrapadas En El Campo
Resumen Se estudió la transmisibilidad de infecciones con tripanosomas a ganado N'Dama, a través de moscas tsetse atrapadas en el campo. LasGlossina palpalis gambiensis atrapadas, fueron transferidas individualmente a jaulas numeradas, donde se alimentaron sobre 14 animales N'Dama sin infección alguna.Una vez completada una comida, las moscas se disecaron buscándose infecciones en la proboscis, glándulas salivares e intestino. Cada animal fue picado por un buen número de moscas, en un rango de cinco a 64. Seguida a la disección de las moscas tsetse, siete bovinos fueron picados por una sola mosca infectada; cinco por dos, mientras que los otros dos fueron cada uno picado por tres tsetse infectadas. Las moscas estaban infectadas conTrypanosoma vivax o con especies de tripanosomas pertenecientes al subgéneroNannomonas, o por ambas especies.Los animales fueron seguidos clínicamente día a día por un período de tres meses por la presencia de tripanosomas en la sangre y anticuerpos en el suero. Se tomaron en cuenta otros parámetros como la temperatura corporal, reacciones cutáneas locales, volumen corpuscular celular y peso corporal. Los primeros tripanosomas se detectaron ocho días después de la picadura de moscas infectadas. Solamente cinco de los 14 bovinos se infectaron, de los cuales tres, habían sido expuestos a una única tsetse infectada. Se detectóTrypanosoma vivax en un animal,T. congolense en dos bovinos más e infecciones mixtas en los otros dos.Estos hallazgos demuestran, que el ganado N'Dama puede infectarse con tripanosomiasis, seguidamente de la picadura de una sola tsetse infectada bajo condiciones de campo. Sin embargo, solamente cinco (posiblemente ocho) de las 23 tsetse infectadas, fueron capaces de transmitir el parásito exitosamente.
Infection Experimentale De Bovins N'Dama Avec Des Trypanosomes A l'Aide DeGlossina Palpalis Gambiensis Capturees A l'Etat Sauvage
Résumé La transmissibilité de possibilité de transmission de la trypanosomose à des bovins N'Dama par des mouches tsé-tsé capturées sur le terrain a été examinée. DesGlossina palpalis gambiensis capturées à l'état sauvage ont été transférées individuellement dans de petities cages numérotées et placées pour se nourrir sur 14 bovins N'Dama indemnes.A la suite d'un repas complet, les mouches ont été disséquées et on a enregistré l'infection dans le proboscis, les glandes salivaires et l'intestin. Chaque animal a été piqué par un nombre de mouches allant de cinq à soixante quatre. A la suite de la dissection des glossines, on a trouvé que sept bovins avaient été piqués par une seule mouche infectée, cinq par deux mouches, alors que les deux derniers avaient servi à nourrir chacun trois glossines infectées. Les mouches tsé-tsé hébergeaient soitTrypanosoma vivax ou une espèce de trypanosomes appartenant au sous genreNannomonas ou par les deux espèces.Les animaux d'expérience ont été suivis quotidiennement pendant trois mois pour observer l'apparition des trypanosomes dans le sang et des anticorps dans leur sérum. D'autre paramètres tels que la température corporelle, les réactions cutanées locales, le volume erythrocytaire et les variations pondérales ont également été mesurés. Les trypanosomes ont été détectés pour la première fois huit jours après la morsure infectante. Seuls cinq des 14 bovins se sont infectés, parmi lesquels trois avaient été exposés à une seule mouche infectée. On a détéctéTrypanosoma vivax chez un animal,T. congolense chez deux bovins et des infections mixtes des deux espèces chez les deux derniers animaux infectés. Ces observations montrent que les bovins N'Dama peuvent devenir infectés par des trypanosomes par la piqure d'une unique mouche tsé-tsé infectée dans les conditions du terrain. Cependant, seulement cinq (peut-être huit) des 23 glosssines infectées ont été capables de transmettre les parasites avec succès.相似文献
992.
S Schwarz M Cardoso H Blobel 《DTW. Deutsche tier?rztliche Wochenschrift》1990,97(11):498, 501-498, 503
A total of 33 Staphylococcus hyicus-cultures from piglets with exudative epidermatitis were analyzed for the presence of antibiotic resistance plasmids. Four small plasmids encoding resistances to chloramphenicol, macrolide-lincosamide-antibiotics, streptomycin or tetracyclines could be identified in plasmid-curing and plasmid-transformation experiments. For further characterization these plasmids were digested with restriction endonucleases. This led to the construction of a specific restriction map for each of the 4 plasmids. On the basis of their restriction maps, these 4 antibiotic resistance plasmids from "porcine" S. hyicus-cultures were compared with the respective resistance plasmids of other staphylococcal species from infections of humans and animals. 相似文献
993.
Efficacy of ceftiofur hydrochloride for treatment of experimentally induced colibacillosis in neonatal swine 总被引:2,自引:0,他引:2
R J Yancey R A Evans D D Kratzer J B Paulissen S G Carmer 《American journal of veterinary research》1990,51(3):349-353
Ceftiofur hydrochloride was tested for effectiveness against induced colibacillosis in neonatal swine. In this model, pigs less than 12 hours old were inoculated via stomach tube with a virulent, K99+, nalidixic acid-resistant strain of Escherichia coli. Six hours after challenge exposure, 1 dose of ceftiofur was administered either IM or orally in experiment 1 and orally only in experiment 2. Mortality, shedding of bacteria, fecal consistency scores, and body weight changes were monitored for 10 days. In experiment 1 (n = 383 pigs), all treatments at dosage that ranged between 0.5 and 64.0 mg of ceftiofur/kg of body weight significantly (P less than 0.001) reduced mortality, bacterial shedding, and diarrhea and increased weight gain, compared with findings in untreated controls. There were no detectable differences between oral and IM routes, except that there was greater reduction in bacteria shedding associated with the oral route of administration. In experiment 2 (n = 505 pigs), ceftiofur was administered orally either once at 6 hours after challenge exposure or twice at 6 and at 48 hours after the first dose. Dosage of ceftiofur was 0, 5, 10, 20, 30, or 60 mg/kg administered once, or half the same dose was administered at each of 2 times. At the optimal dosage (10 mg/kg), a single dose was as effective as 2 doses. The single administration at all dosages reduced mortality, bacterial shedding, and diarrhea scores and increased body weight gain, compared with findings in untreated pigs (P less than 0.01). In this induced infection model, the optimal treatment dosage was determined to be 10 mg/kg administered once. 相似文献
994.
S Avgeris C D Lothrop T P McDonald 《Journal of the American Veterinary Medical Association》1990,196(6):921-924
Plasma von Willebrand factor antigen concentration was determined in 15 dogs with suspected hypothyroidism, in 1 dog with hyperthyroidism, and in 14 euthyroid dogs. The mean +/- SEM von Willebrand factor:antigen concentration in hypothyroid dogs (47.1% +/- 12.6%) was significantly decreased (P less than 0.0005), compared with that in euthyroid dogs (94.7 +/- 5.6%). Four hypothyroid dogs were given thyroxine for 1 month and all 4 had an increase in von Willebrand factor:antigen concentration. The plasma von Willebrand factor:antigen concentration was 200% in the hyperthyroid dog. Seemingly, reduced concentrations of plasma von Willebrand factor:antigen can be found in dogs in association with congenital von Willebrand disease or with von Willebrand disease acquired through hypothyroidism. 相似文献
995.
I M Ismail F Mohamed N M Aly N M Allam H B Hassan M S Saber 《Archiv fuer experimentelle veterinaermedizin》1990,44(5):789-792
2 Egyptian goats and Boscat rabbits were experimentally inoculated with peste des petits ruminants (PPR) local Egyptian strain (PPR, Egypt 87). The inoculated animals contracted the disease with minor clinical manifestations, accompanied by rise of neutralizing antibodies to PPR virus. Virus was isolated from ocular and nasal secretions, buffy coat, spleen, and liver. No contact infection was observed between inoculated and healthy goats. 相似文献
996.
P J Armstrong M S Hand G S Frederick 《Veterinary Clinics of North America: Small Animal Practice》1990,20(1):237-275
When oral intake is unsatisfactory or contraindicated, maintenance of nutrition by tube feeding is an alternative to the parenteral route. A large volume of research data supports the decision to use the enteral route whenever possible. Entry of food into the alimentary tract is a stimulus to structural and functional maintenance of that tract. Enteral nutrition can be given via indwelling nasoesophageal, pharyngostomy, esophagostomy, percutaneous or surgical gastrostomy, or enterostomy tube. Use of an appropriate catheter, familiarity with the technique used, and careful patient selection and monitoring are important factors in successful tube feeding. Blenderized pet food diets should be fed whenever possible; commercially available liquid diets provide an alternative when tube caliber or patient factors preclude the use of blenderized foods. 相似文献
997.
Procollagen type-III aminoterminal peptide in serum and synovial fluid of dogs with hip dysplasia and coxarthrosis 总被引:1,自引:0,他引:1
J S Madsen L T Jensen H Str?m K H?rslev-Petersen E Svalastoga 《American journal of veterinary research》1990,51(10):1544-1546
Hip dysplasia is an affection of the coxofemoral joint that progresses until stabilization is caused by fibrosis and osteoarthritic changes. This stabilization process can be examined by clinical and radiographic methods. The capability of evaluating the procollagen concentrations in liquids, such as serum and synovial fluid, has further offered the basis for an objective biochemical evaluation of the stabilization process. Our study was performed to evaluate whether determination of procollagen concentrations was suitable for the use in practice. The procollagen type-III aminoterminal peptide (P-III-NP) concentration was measured in serum and in synovial fluid from coxofemoral joints in 20 dogs. Dogs were grouped on the basis of evidence of dysplasia and osteoarthritic changes of the hip: (1) a control group of 6 dogs without clinical or radiographic signs of hip dysplasia, and (2) dysplastic group of 14 dogs, which was further grouped with respect to the coxofemoral joint laxity, as determined by the Ortolani test. Synovial fluid concentration of P-III-NP was significantly (P less than 0.05) higher in fluid from dysplastic joints than in fluid from normal joints. Serum concentrations of P-III-NP were significantly (P less than 0.05) higher in dogs in which results of the Ortolani test were positive. 相似文献
998.
E A Morris B S McDonald A C Webb L J Rosenwasser 《American journal of veterinary research》1990,51(1):59-64
Interleukin-1 (IL-1) is a protein secreted by stimulated cells of the monocyte-macrophage line, which has a number of important biologic activities. Interleukin-1 has been implicated in the induction and augmentation of the pathologic processes involved in arthritis and articular cartilage destruction. Horses develop osteoarthritis with a frequency and degree of severity similar to human beings. To further document the similarity of the osteoarthritic process in people and horses, the synovial fluid from 5 horses with clinical osteoarthritis was tested for IL-1 bioactivity. Interleukin-1 activity was found in all tested synovial fluids. Upon column chromatography, the synovial fluid-derived factor had a molecular weight consistent with that of IL-1 in other mammalian species. Ion exchange chromatography of osteoarthritic synovial fluid revealed the principal peaks of bioactivity to be in the fractions with isoelectric points of 7.2, 5.4, and 4.7, which are characteristic of IL-1. A considerable degree of homology between human and equine IL-1 was demonstrated by the cross hybridization of human IL-1 beta cDNA probe with RNA derived from IL-1-producing equine adherent monocytes. These results indicate that equine IL-1 is in all of the osteoarthritic equine joints tested and that equine IL-1 has many of the characteristics of IL-1 isolated from other species. 相似文献
999.
Antimicrobial supplementation of growing pigs: the effect of porcine sera fractions on in vitro muscle cell proliferation 总被引:1,自引:0,他引:1
M R Hathaway M S Pampusch S G Cornelius C E Allen W R Dayton 《Journal of animal science》1990,68(11):3642-3648
Sera obtained from pigs before and after subtherapeutic levels of ASP250 supplementation (pre and post serum pools) have been subjected to comparative fractionation by using gel filtration and affinity chromatography on immobilized Cibacron Blue F3G-A. Comparable serum fractions obtained from pre- and post-ASP250 blood sera were assayed in muscle cell culture bioassays designed to measure their effect on proliferation. Pre- and post-ASP250 sera were subjected to gel filtration and divided into the following fractions: fraction 1, Kav less than .17; fraction 2, Kav = .17 to .41; fraction 3, Kav = .41 to .59. Post-ASP250 fractions 2 and 3 increased proliferation rate in cultured muscle cells to a greater extent than comparable pre-ASP250 fractions (P less than .001). Chromatography of fraction 3 on immobilized Cibacron Blue F3G-A showed that both pre- and post-ASP250 fraction 3 contained a putative inhibitor of myogenic cell proliferation as well as mitogenic factors. However, negative growth factor activity was greater in pre-ASP250 fraction 3 than in post-ASP250 fraction 3 (P less than .05). Additionally, positive growth factor activity was lower in pre-ASP250 fraction 3 than in post-ASP250 fraction 3 (P less than .05). These data suggest that levels and(or) activities of both positive and negative muscle growth factors in serum may be altered by the addition of antimicrobials to the diets of growing pigs. 相似文献
1000.
Analysis of southern Ontario Actinobacillus (Haemophilus) pleuropneumoniae isolates by restriction endonuclease fingerprinting. 总被引:2,自引:1,他引:2 下载免费PDF全文
J I MacInnes J D Borr M Massoudi S Rosendal 《Canadian journal of veterinary research》1990,54(2):244-250
Isolates of Actinobacillus (Haemophilus) pleuropheumoniae were studied by restriction endonuclease fingerprinting (REF) analysis using the enzymes BamHI and HindIII. Restriction fragments were resolved by polyacrylamide gel electrophoresis and visualized by silver staining. Except for serotypes 1 and 9, reference strains of A. pleuropneumoniae serotypes 1 to 10 had clearly distinguishable REF profiles. Analysis of REF profiles of southern Ontario field isolates revealed limited heterogeneity amongst isolates of serotype 1 or serotype 5. The REF profiles of the serotype 7 isolates studied showed greater variation. Heterogeneity could not be correlated with the presence of plasmids nor with antibiotic resistance. Limited heterogeneity could also be detected amongst REF profiles of A. pleuropneumoniae isolates recovered from a closed herd suggesting that there is a small amount of genetic variation within clonal populations. 相似文献