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91.
In this investigation, we determined the prevalence of the Ornithobacerium rhinotracheale (ORT) infection in broilers and broiler breeders in southern Brazil. We also correlated the presence of antibodies in broilers with performance. Sera from 1550 broilers from 50 flocks were collected during the slaughter time in nine companies with federal veterinary inspection of the state of Rio Grande do Sul. Sera from 480 meat-type breeders of 40 flocks from 14 companies in southern Brazil were also analyzed by enzyme-linked immunosorbent assay, and the prevalence of antibodies was determined. The prevalence of ORT antibodies in broiler flocks was 63.83%, but in each individual flock only 6.52% of the birds were positive. The prevalence in broiler breeder flocks was 100.00%, and in each individual flock 94.62% of the birds were positive. There was a positive correlation between the presence of antibodies to ORT and decreased body weight in broilers. There was no significant correlation between presence of antibodies to ORT and age, lineage, efficiency index, feed conversion, and mortality. There was a positive correlation between the presence of respiratory signs and antibodies to ORT, although the reverse correlation was not significant. These results confirm that ORT is present and widespread in broilers and broiler breeders in southern Brazil. 相似文献
92.
Belozerov VN Van Niekerk DJ Butler HJ 《The Onderstepoort journal of veterinary research》2003,70(4):325-330
During winter populations of Argas arboreus from heronries of the cattle egret, Bubulcus ibis, in South Africa are composed of adults, with some predominance of males, and II-IV instar nymphs, in a state of diapause. The period of tick activity, including reproduction and development of eggs, larvae and N1 nymphs, is synchronized with the nesting and breeding season of their avian hosts. It begins during spring with the return of birds to the heronry, and ceases in autumn through induction of reproductive diapause in engorged females, and behavioural diapause in unfed nymphs and adult ticks. Many ticks showed morphological anomalies and malformations, the study of which could possibly be used for monitoring of environmental pollution. 相似文献
93.
van Duijkeren E Box AT Mulder J Wannet WJ Fluit AC Houwers DJ 《Tijdschrift voor diergeneeskunde》2003,128(10):314-315
In the Netherlands, methicillin resistant Staphylococcus aureus (MRSA) are regularly isolated from humans. We present the first isolation of MRSA from animal origin in the Netherlands. A coagulase positive staphylococcus was cultured from an infected wound in a Dutch dog that recently underwent surgery abroad. The staphylococcus was resistant to methicillin, ampicillin, amoxycillin + clavulanic acid, cephalexin, erythromycin, lincomycin, tetracycline, gentamicin and enrofloxacin. It was identified as S. aureus by fermentation of mannitol and Martineau-PCR. The presence of mecA was confirmed by PCR. 相似文献
94.
In 1998 a questionnaire was sent to graduates from all the veterinary schools in Great Britain and Ireland who had obtained their veterinary degree within the previous five years, to assess their opinions of the undergraduate clinical veterinary curriculum. Ninety-five per cent of the graduates who responded were working full time in veterinary practice, with small animal work occupying 90 per cent of them for a median of 70 per cent of their time. Their assessment of the curriculum suggested that they were generally satisfied, but that there were some subjects they considered important in which the teaching and extramural studies had failed to provide adequate learning opportunities. Twelve subjects were rated as 'very important', two subjects, small animal medicine and anaesthesia, were considered to be 'very well' taught, and extramural studies were considered to be 'very useful' for three subjects, small animal surgery, cattle medicine and cattle surgery. The survey provided evidence that graduates are keen to continue learning and specialise after they graduate. 相似文献
95.
96.
Pasnik DJ Vemulapalli R Smith SA Schurig GG 《Veterinary immunology and immunopathology》2003,95(1-2):43-52
A recombinant vaccine was constructed for piscine mycobacteriosis utilizing a Brucella abortus strain RB51 vector expressing a mammalian Mycobacterium sp. 85A antigen. Juvenile striped bass were inoculated with the resulting construct at doses equivalent to 10(6), 10(7), 10(8), 10(9), and 10(10) colony-forming units/fish. Blood and tissue samples from these fish demonstrated significant specific humoral and cell-mediated immune responses towards the 85A antigen in a dose-dependent manner. However, survival studies determined that inoculated fish failed to demonstrate cross-protective responses after live Mycobacterium marinum challenge 70 days post-inoculation. 相似文献
97.
Puccio M Marino DJ Stefanacci JD McKenna B 《Journal of the American Animal Hospital Association》2003,39(5):473-478
A retrospective study was performed describing the clinical presentations, radiographic findings, and surgical outcomes of 17 dogs (18 elbows) following medial coronoidectomy for the treatment of elbow joint incongruity as a sole disease entity. Complete resolution of lameness was achieved in 100% of the cases. The mean radiographic arthrosis grade progressed in 70% of the cases. Results of this study indicate that resolution of clinical lameness may be achieved with medial coronoidectomy in dogs with elbow incongruity; however, progression of degenerative joint disease with unknown, long-term clinical significance can be expected after surgery. 相似文献
98.
Anderson GM Lewis DD Radasch RM Marcellin-Little DJ Degna MT Cross AR 《Journal of the American Animal Hospital Association》2003,39(5):479-498
Fracture stabilization using circular external skeletal fixation was evaluated in 14 dogs with antebrachial fractures and 11 dogs with crural fractures. Most dogs were consistently weight bearing on the stabilized limb by 3 days following surgery. Although all dogs developed minor wire/pin tract inflammation and eight dogs developed major wire/pin tract inflammation, postoperative lameness was not consistently associated with wire/pin tract complications. Fractures in 23 dogs achieved radiographic union (mean +/- standard deviation [SD], 61 +/- 21 days; median, 57 days) without additional surgery; two dogs required restabilization of their fractures with linear fixators. Twenty of the 21 owners that could be contacted felt their dog had no (n=15) or only a mild (n=5) intermittent lameness at the time of final, long-term (mean +/- SD, 37 +/- 17 months; median, 42 months) assessment. 相似文献
99.
Wright IM Smith MR Humphrey DJ Eaton-Evans TC Hillyer MH 《Equine veterinary journal》2003,35(6):613-619
REASONS FOR PERFORMING STUDY: Contamination and infection of synovial cavities are a common occurrence in clinical practice and, if inadequately treated, may have career or life threatening consequences for affected horses. HYPOTHESIS: The objectives in treating contamination and infection of joints, tendon sheaths and bursae are most effectively met by endoscopic surgery. METHODS: Over a 6 year period, cases of synovial contamination and infection admitted to a referral clinic were evaluated and treated endoscopically. The horses received local and systemic antimicrobial drugs with minimal nonsteroidal anti-inflammatory medication but no other medical or surgical treatment. All arthroscope and instrument portals and, whenever possible, all traumatic wounds were closed. Diagnostic information, endoscopic observations and results of treatment were evaluated retrospectively. RESULTS: A total of 140 affected animals were referred and 121 cases were treated endoscopically. These involved 70 joints, 29 tendon sheaths, 10 bursae and in 12 cases a combination of synovial cavities. The most common aetiologies were open wounds (n = 54) and self-sealing punctures (n = 41). Foreign material was identified endoscopically in 41 but predicted prior to surgery in only 6 cases. Osteochondral lesions were evident at surgery in 51 and recognised before surgery in 25 cases; 32 horses had intrathecal tendon or ligament defects. Follow-up information was obtained for 118 animals; 106 (90%) survived and 96 (81%) returned to their preoperative level of performance. The presence of osteitis/osteomyelitis, other osteochondral lesions and marked deposits of pannus were associated with nonsurvival. For those animals which survived, non-Thoroughbred horses, a combination of synovial structure involvement and regional i.v. antimicrobial administration were associated with reduced post operative performance. Marked pannus, regional i.v. antimicrobial administration and duration of systemic antimicrobial administration were associated with a group combining nonsurviving animals and those with reduced post operative performance. CONCLUSIONS: Endoscopic surgery makes a valuable contribution to the management of synovial contamination and infection. POTENTIAL RELEVANCE: The information obtained from and therapeutic options offered by endoscopy justify its early use in cases of synovial contamination and infection. 相似文献
100.
OBJECTIVE: To evaluate lipopolysaccharide (LPS)-induced activation of equine neutrophils in blood. SAMPLE POPULATION: Blood samples from 5 healthy adult Thoroughbreds. PROCEDURES: Neutrophil integrin (CD11/CD18) expression, size variation, degranulation, and deformability were measured with and without incubation with LPS. Time and concentration studies were done. The mechanism of endotoxin-induced neutrophil activation was investigated by inactivating complement or preincubating neutrophils with inhibitors of tumor necrosis factor-alpha (TNF-alpha) synthesis, prostaglandin-leukotriene synthesis, or platelet-activating factor. RESULTS: Incubation of equine neutrophils with LPS increased cell surface expression of CD11/CD18, decreased neutrophil deformability, increased and decreased neutrophil size, and induced neutrophil degranulation. The LPS-induced neutrophil activation was attenuated by addition of inhibitors of TNF-alpha and prostaglandin-leukotriene synthesis. CONCLUSIONS AND CLINICAL RELEVANCE: Equine neutrophils are readily activated in vitro by LPS, resulting in increased expression of integrin adhesion molecules, decreased deformability, variation in neutrophil size, and degranulation. The tests used to detect activated neutrophils in this study may be useful in detecting in vivo neutrophil activation in horses with sepsis and endotoxemia. 相似文献