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1.
Abstract

Extract

Madam:— The N.Z.V.A. Nominee on the National Hydatids Council, Mr Peter Malone, in his annual report states that he knows of “no professional concerns that would allow certificates to be issued to exempt dogs from dosing with droncit, and on receipt of copies of such certificates will continue to forward them to the Veterinary Council to examine for disciplinary action”. (1 1985. Report of the N.Z.V.A. Nominee on the National Hydatids Council: N.Z.V.A. Annual Report 4343.  [Google Scholar] In September 1985 I examined a nine year old miniature poodle dog that had been dosed with droncit by a hydatids control officer two hours previously. The dog had collapsed into lateral recumbancy, was pale and cyanotic with a rectal temperature of 37.3°C. Cardiac and thoracic auscultation was normal, and no other abnormal clinical signs were detected. There was no previous history of similar episodes and the dog has been dosed with droncit several times beforehand without problems. The dog was treated with betamethasone and millophylline and made a full recovery within 48 hours.  相似文献   
2.
Thirteen dogs with histopathologically confirmed malignancies were treated with mitoxantrone and cyclophosphamide combination therapy. One to four doses were administered at 21-day intervals. Recombinant human granulocyte colony-stimulating factor was administered to ameliorate myelosuppression in dogs with neutrophil nadirs less than 1,000/microl. While the protocol appears to be safe for use in tumor-bearing dogs, an advantage over mitoxantrone single-agent protocols in terms of tumor response was not demonstrated in this initial pilot study.  相似文献   
3.
The in vitro production of proinflammatory cytokines after stimulation with Actinobacillus pleuropneumoniae and the relation of these cytokines in vivo with the disease caused by A. pleuropneumoniae were investigated. Within 24 h, in vitro stimulation by A. pleuropneumoniae (serotype 1) preparations, including killed bacteria, bacterial culture supernatant, lipopolysaccharide, and bacterial extracts, porcine pulmonary alveolar macrophages (PAM) produced significant (P < 0.05) amounts of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) as measured by bioassays. The supernatants containing interleukin-8 from PAM after stimulation by bacterial preparations showed significant neutrophil chemotaxis, while bacterial preparations alone did not. After in vivo infection with A. pleuropneumoniae, the mean levels of TNF-alpha and IL-1 in serum, as measured by bioassays, were elevated 37- to 27836-fold for TNF-alpha and 11- to 5941-fold higher for IL-1 within 4 d post-infection, depending on the treatments, and remained elevated up to Day 7. Both cytokines were also detected in porcine lungs by bioassays and immunocytochemistry. The results indicated that both secreted and surface components of A. pleuropneumoniae can stimulate PAM to produce proinflammatory mediators. Neutrophil chemoattractants rather than bacterial components are the major factor causing acute lung inflammation. The elevation of TNF-alpha and IL-1 in pigs occurred coincident with the onset of acute clinical disease.  相似文献   
4.
Chronic pneumonia was investigated in a litter of young Chinese Shar Pei in which 4 of 6 dogs were affected. Serum immunoglobulin concentrations (IgA, IgG, IgM) determined by radial immunodiffusion varied over time, but were not consistently lower in affected dogs, compared with control dogs. Two dogs that died had hydrocephalus and lymphoid depletion, in addition to severe broncho-pneumonia. Evaluation of ciliary ultrastructure in 2 affected dogs revealed random orientation of adjacent respiratory tract or oviductal cilia and a greater number of microtubular disarrangements, compared with control dogs. In vivo tracheal mucociliary clearance of 99mtechnetium macroaggregated albumin was absent in 1 dog examined. The ciliary abnormalities were suspected to have resulted in an inefficient mucociliary transport system predisposing to the development of pneumonia. Further evaluation of 1 Chinese Shar Pei revealed lymphocyte mitogenesis results that were not consistently less than those of a control dog, normal total hemolytic complement values, and normal blood neutrophil chemotaxis.  相似文献   
5.
The analysis of CpG ODN induced innate immune responses in different animal species has shown substantial similarities and differences in levels and types of induced cytokines profile. The objectives of these studies were to identify innate immune biomarkers activated by three classes of CpG ODNs in pigs. For this purpose, we investigated the kinetics of innate immune responses in immune cells from pigs following in vitro and in vivo stimulation with CpG ODNs. The mRNA expression of cytokine and chemokine genes were assayed by SYBR@ green based quantitative real time PCR. A-class CpG ODN induced significant but transient levels of IFN-γ, IL-12 (P40), IL-6, IL-4 and TNF-α mRNA, C-class CpG ODN induced significant level of IFN-γ, IFN-α and IL-12 mRNA and the lowest level of IL-4 (Th-2 type) mRNA. A very low level of some cytokines stimulation was observed by GC ODNs. It is noteworthy, that IL-12 (P35) mRNA was significantly stimulated by B-class GpC ODN 7909. Interestingly, all classes of CpG ODNs induced significant level of IP-10 at 12 h post stimulation. These in vitro and in vivo observations suggest that interferon-γ inducible protein 10 (IP-10) may be a reliable biomarker for immune activity induced by CpG ODNs in pigs.  相似文献   
6.
7.
Two field trials were conducted in a beef cow herd in Saskatchewan to determine the effectiveness of a combined Pasteurella haemolytica and Haemophilus somnus vaccine in increasing passively and actively acquired antibodies in beef calves. Vaccination of dams at 4 and/or 7 weeks prepartum was associated with increased antibody titers to P. haemolytica and H. somnus in their serum (P < 0.05), colostrum (P < 0.05), and serum of their calves at 3 days and 1 month of age (P < 0.05). There was no significant (P > 0.05) difference in antibody titers in the colostrum and serum of calves from single or double vaccinated dams. Calves vaccinated at 1 and 2 months of age in the face of maternal antibodies to P. haemolytica and H. somnus had significantly (P < 0.05) higher antibodies to P. haemolytica and H. somnus at 4 and 6 months of age than did unvaccinated calves. Calves vaccinated at 3 and 4 months of age in the face of low levels of preexisting antibodies had significantly (P < 0.05) higher antibodies to P. haemolytica at 5 months of age and to H. somnus at 5 and 6 months of age than did unvaccinated calves. Calves vaccinated once at 4 months of age had significantly (P < 0.05) higher antibody titers to P. haemolytica and H. somnus at 4.5 months of age than did unvaccinated calves, but this difference was not apparent at 6 months of age.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
In a replicated 4 × 4 Latin square experiment conducted in summer, eight mature Thoroughbred horses received two diets, control and fat-supplemented, and were exercised at two fitness levels designed to increase daily digestible energy (DE) requirements to approximately 150% (fitness level I) and 200% (fitness level II) of maintenance. In a second experiment during the winter, horses received the two diets in a switchback design and exercised at fitness level II. After 3 wk adaptation to treatments, feed and fecal samples were collected and horses galloped a standardized exercise test (SET) designed to increase the heart rate above 185 bpm for 1200 m. Vital signs were monitored and blood samples were obtained. Feed intake increased as fitness level increased (P < .05). Horses on the fat-supplemented diet required less feed (P < .05) to meet the energy requirements at a given fitness level. Daily DE intake was higher (P < .05) for the horses exercised at fitness level II to meet the increased metabolic demands. Heart rate, respiration rate and rectal temperature all increased (P < .05) with exercise. No treatment effects were found for heart rate (P >. 10) or rectal temperature (P > .30). Horses exercised in the winter had lower (P < .05) respiration rates, indicative of less problems dissipating excess body heat. Plasma aldosterone concentrations increased (P < .05) with exercise, corresponding to an increase in plasma K concentrations. Horses exercised in the summer exhibited higher (P < .05) plasma aldosterone concentrations than horses worked in the winter. Plasma CI and Na concentrations did not change (P > .30) with any treatment or exercise, indicating that the horses were not sufficiently stressed to induce any significant dehydration.  相似文献   
9.
Monensin, a polyether ionophore antibiotic, is potentially an important agent for bloat relief in dairy cows grazing temperate legume-based pasture. A series of studies was undertaken to determine the effect of monensin, when delivered continuously in the rumen of lactating dairy cows by means of controlled-release capsules (monensin CRC). Such devices release approximately 300 mg/head/day for 100 d. A short-term pilot study made at Ruakura, New Zealand, tested monensin CRC in cows selected for high susceptibility to bloat and grazing lucerne (Medicago sativa) or red clover (Trifolium pratense). Treatment significantly reduced the incidence of bloat, while milk yield and protein yield were increased. There was no effect on fat yield. Following the pilot study, 6 large-scale field experiments involving a total of 368 lactating dairy cows, were made in Australia and New Zealand to confirm the effectiveness of monensin CRC for bloat control and to measure the effect of such treatment on milk production and composition. A severe bloat problem occurred in 2 experiments, mild bloat occurred in 2 others, while no visual signs of bloat were observed in the remaining 2 experiments. Bloat was significantly (P less than 0.05) reduced by monensin CRC treatment when data was pooled over the 4 experiments in which bloat occurred. Daily milk yield was increased in all experiments from a mean of 17.7 in untreated groups to 18.8 kg/head/day (P less than 0.05) in monensin CRC-treated cows. Protein percentage was not affected by treatment, while there was a decrease from 4.29 to 4.10% fat, although total fat yield was not affected.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Monensin toxicity in cattle   总被引:3,自引:0,他引:3  
Monensin has been tested to determine its toxicity and safety in cattle. Single dose acute toxicity and signs associated with toxicity were determined by oral gavage, 7-d oral gavage and feeding experiments with high concentrations of monensin in feed. Oral feeding studies indicated a near complete anorexia resulting from intake of sublethal amounts of monensin. In these cases, cattle recovered from the insulting dose and resumed growth and feed intake. In long-term chronic feedlot, pasture supplement, and reproduction safety studies conducted with monensin administered in the feed, the high concentrations caused cattle to show signs of mild monensin intoxication. Mortality resulted from feeding groups of cattle large quantities of monensin in small quantities of feed. Furthermore, these studies have demonstrated no detrimental effects upon reproduction. Collectively, these studies indicate that the greatest risk of intoxication occurs when cattle first receive a feed containing monensin. Mixing errors and misuse situations under actual use conditions have resulted in cases of cattle mortality. In most cases the mortality was predictable based upon the exposure in controlled studies.  相似文献   
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