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101.
Mercier P Alves-Branco F Sapper Mde F White CR 《American journal of veterinary research》2003,64(10):1221-1224
OBJECTIVE: To evaluate the safety of an orally administered ivermectin and praziquantel paste with regard to variables associated with clinical findings, parturition, lactation, maternal care, and neonate viability in pregnant mares. ANIMALS: 40 pregnant mares. PROCEDURE: Mares were randomly allocated into treatment (n = 20) and control (20) groups and administered a placebo or 3 times the therapeutic dosage of ivermectin (0.6 mg/kg) and praziquantel (4.5 mg/kg) at 14-day intervals until parturition. Physical examinations were performed on mares and their foals after parturition (on postpartum days 30, 60, and 90) to identify any drug-related effects. As an aid in assessing general health, hematologic and serum biochemical analyses were performed monthly on the mares. RESULTS: In blood constituents, minor alterations that were not biologically important were observed. Reproductive performance was not affected by the unusual treatment duration or high dosage, although the drugs were administered during a crucial period of equine embryonic development (30 to 60 days). Neither adverse effects on mares nor abortions occurred. Follow-up evaluations of the foals for a 3-month period did not detect any abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of the ivermectin-praziquantel paste appears to be safe in pregnant mares and their foals. 相似文献
102.
Navegantes LC Machado CR Resano NM Migliorini RH Kettelhut IC 《British poultry science》2003,44(1):149-154
1. The role of beta2-agonist and of cAMP in chick skeletal muscle proteolytic pathways and protein synthesis was investigated using an in vitro preparation that maintains tissue glycogen stores and metabolic activity for several hours. 2. In extensor digitorum longus (EDL) muscle total proteolysis decreased by 15 to 20% in the presence of equimolar concentrations of epinephrine, clenbuterol, a selective hbetaagonist, or dibutyryl-cAMP. Rates of protein synthesis were not altered by clenbuterol or dibutyryl-cAMP. 3. The decrease in the rate of total protein degradation induced by 10(-5)M clenbuterol was paralleled by a 44% reduction in Ca2+-dependent proteolysis, which was prevented by 10(-5)M ICI 118.551, a selective fbeta2antagonist. 4. No change was observed in the activity of the lysosomal, ATP-dependent, and ATP-independent proteolytic systems. Ca2+-dependent proteolytic activity was also reduced by 58% in the presence of 10(-4)M dibutyryl-cAMP or isobutylmethylxanthine. 5. The data suggest that catecholamines exert an inhibitory control of Ca2+-dependent proteolysis in chick skeletal muscle, probably mediated by fbeta2adrenoceptors, with the participation of a cAMP-dependent pathway. 相似文献
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104.
Eguaras M Palacio MA Faverin C Basualdo M Del Hoyo ML Velis G Bedascarrasbure E 《Veterinary parasitology》2003,111(2-3):241-245
The efficacy of formic acid in a gel matrix was evaluated in two groups of honeybee colonies. In Group 1, a dispenser with 120 g of formic acid (70%) in gel was placed on the brood combs and another dispenser with the same dose was located on the hive bottom (total dose, 240 g). Group 2 received two doses of 240 g of formic acid (70%) in gel and each application was applied in two dispensers containing 120 g of the formic acid solution each and they were located over the brood chamber (total dose, 480 g). In Group 2, the period between both applications was 15 days, and the efficacies after the first and both applications were calculated. Significant differences were registered for final efficacy between both groups. When final efficacy of Group 1 was compared with efficacy after first application of Group 2, significant differences were found (P=0.0005). Same doses in different positions within the hive have different final efficacy. The higher efficacy was registered when the dispensers were placed over brood combs and on the hive bottom. It is suggested that efficacy is related to dispenser position within the hive. 相似文献
105.
Avian pathogenic Escherichia coli (APEC) are often found in poultry and are responsible for a set of diseases, commonly referred to as avian colibacillosis. One of the important virulence factors is adhesion to different epithelial surfaces, which is mediated by pili. P pili are thought to play a role by means of their PapG adhesin, which occurs in three molecular variants: PapGI, PapGII and PapGIII. This study is the first to determine and analyse the distribution of the different papG alleles in APEC. Our results show a significant predominance of the papGII allele above all other alleles or allele combinations. No statistically significant associations could be found between papG allele distribution and the type of bird, organ of isolation and O serogroup. Finally, the papGII and papGIII sequences showed high homology with mammalian (including human) source papG sequences. 相似文献
106.
Dynamics of porcine circovirus type 2 infection in a herd of pigs with postweaning multisystemic wasting syndrome 总被引:6,自引:0,他引:6
Rodríguez-Arrioja GM Segalés J Calsamiglia M Resendes AR Balasch M Plana-Duran J Casal J Domingo M 《American journal of veterinary research》2002,63(3):354-357
OBJECTIVE: To determine the pattern of infection for porcine circovirus type 2 (PCV2) in a herd of pigs with postweaning multisystemic wasting syndrome (PMWS). ANIMALS: 29 sows and 250 pigs. PROCEDURE: Blood samples were collected from all 3-, 7-, and 12-week old pigs and 59 pigs at 28 weeks of age. Pigs that died during the study were necropsied. Porcine parvovirus and PCV2 antibodies were assayed. A polymerase chain reaction (PCR) was used to detect PCV2 genome in serum of selected pigs. RESULTS: The PMWS started when pigs were 8 weeks old, with a prevalence of 30% in 8- to 10-week-old pigs. Eighty-three pigs died during the period between 3 and 12 weeks of age. Microscopic lesions consistent with PMWS were observed, and PCV2 nucleic acid was detected (50 of 68 pigs). Antibodies to PCV2 decreased from 3 to 7 weeks of age, increased at 12 weeks of age, and were maintained until 28 weeks of age. One sow had a positive result for PCR of serum. Nine, 37 and 8 pigs had PCV2 genome in serum obtained at 7, 12, and 28 weeks of age, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Infection with PCV2 coincided with severe clinical signs; however, infected 28-week-old pigs did not have evidence of disease. Immunity declined over time in young pigs. A long duration of PCV2 viremia was apparent in a high percentage of infected pigs, which may affect transmission and persistence of the virus in a herd. 相似文献
107.
108.
109.
OBJECTIVE: To evaluate use of a pasteurized tumoral autograft prepared from the resected primary bone neoplasm for limb sparing in a dog with distal radial osteosarcoma (OSA). STUDY DESIGN: Clinical case report. ANIMALS: A 9-year-old male Maremma shepherd dog. METHODS: After right distal radial OSA removal, the tumoral autograft was pasteurized. The excised bone segment was placed in a sterile watertight box containing sterile saline solution preheated to 65 degrees C in a water bath. The box was kept immersed in the water bath at 65 degrees C for 40 minutes to kill the tumor cells. The autograft was then fixed in the host with a plate and screws based on standard AO/ASIF technique for carpal arthrodesis. Three doses of cisplatin (70 mg/m(2) intravenously) were administered, 3 weeks apart; the initial dose was administered the day after surgery. RESULTS: The autograft was incorporated in a manner comparable to an allograft, and after 708 days, the metallic implants were removed. A 1-month activity restriction as well as spoon splint to protect the leg from a full loading were used thereafter. Limb function was fair to good, and the dog remains disease free after 56 months. CONCLUSIONS: A pasteurized autograft consisting of the resected primary bone neoplasm is a valid alternative to a cortical bone allograft for limb sparing in dogs with appendicular OSA in terms of feasibility and pattern of healing. CLINICAL RELEVANCE: This procedure can be an alternative method of limb sparing when difficulties are encountered in establishing and maintaining a canine bone allograft bank. 相似文献
110.
Guarga JL Moreno J Lucientes J Gracia MJ Peribáñez MA Castillo JA 《Veterinary immunology and immunopathology》2002,88(1-2):13-20
The efficacy of specific immunochemotherapy against Leishmania infantum infection in dog was studied. The effects on transmission of the disease, as well as the cellular and humoral immune response were examined. The treated animals showed a significant reduction in the infection rates that were detected in Phlebotomus perniciosus females fed on the dog. The humoral immune response, assayed with an indirect immunofluorescence antibody test (IFAT), did not show significant variations under the influence of the therapy. The characterisation of the peripheral blood mononuclear cells (PBMC) using flow cytometry indicated a significant increase in the proportion of T lymphocytes, especially of CD4/TcR(alpha)(beta)(+) and CD4/CD45RA(+) cells, without showing evidence for modifications in the other leukocyte subsets. Cellular lymphoproliferation studies indicated a lack of a specific response to soluble leishmanial antigen (SLA), but the non-specific lymphoproliferative capacity assayed with phytohemagglutinin (PHA) was maintained. 相似文献