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991.
Gunn GJ Saatkamp HW Humphry RW Stott AW 《Preventive veterinary medicine》2005,72(1-2):149-62; discussion 215-9
The objective of this paper is to present a preliminary assessment of variation in the economic impact of bovine viral diarrhoea virus (BVDV) at dairy farm level between a sample of nations within the EU and hence assess differences in pressure to respond to this disease that may be impeding progress in control and hence restricting collective benefits from healthier livestock. We used a questionnaire to obtain national average values of key epidemiological and economic parameters for a typical dairy farm from BVDV experts in the countries concerned. These parameters were converted into assessments of economic impact using a computer simulation model. Uncontrolled output losses for a BVDV-na?ve herd with virus introduced in year 1 of a 10-year epidemic represented 22, 7, 8, 5, 8 and 20% of the BVDV-free annuity for the UK, Northern Portugal, Holland, Norway, Italy and Germany, respectively. Differences between countries will be widened by differences in the risk of acquiring BVDV. These will be much reduced in countries, such as Norway that have a national BVDV eradication programme. Farmers in such countries can therefore justify spending much less on maintaining BVDV-free status than BVDV-free farms in other countries. This result illustrates the paradox that in countries where BVDV prevalence is high, farmers have least to gain from unilateral BVDV eradication because of the high cost of maintaining freedom from the disease. We discuss this issue in the light of increasing recognition at international level of the importance of BVDV control. 相似文献
992.
2005 Guidelines for the diagnosis, prevention and management of heartworm (Dirofilaria immitis) infection in dogs 总被引:2,自引:0,他引:2
993.
Approximately 88% of Norwegian dairy cattle are housed in tie stalls. Free stall housing for all dairy cattle will be implemented within 20 years. This means that the majority of existing stalls will be rebuilt in the near future. Fifty-seven free stall herds of the Norwegian Red breed were randomly selected and 1547 cows and 403 heifers were trimmed by 13 claw trimmers during the late winter and spring of 2002. The claw trimmers had been taught diagnosing and recording of claw lesions. Environment, management- and feeding routines were also recorded. Fifty-three herds had concrete slatted alleys while 4 had solid concrete. Thirty-five herds had concrete as a stall base, while 17 had rubber mats, 2 had wood and 3 had deep litter straw beds. The prevalence of lameness was 1.6% in hind claws. Models for lameness and claw lesions were designed to estimate the influence of different risk factors and to account for the cluster effects within herd and claw trimmer. Detected risk factors for lameness were: parity three and above and narrow cubicles; for heel horn erosions: lactation stage around 5-7 months after calving and solid concrete alleys; for haemorrhages of the white line: lactation stage around 3-5 months after calving and solid concrete alleys; for haemorrhages of the sole: parity one, lactation stage around 5-7 months after calving and short cubicles, for white line fissures: slatted concrete alleys; for asymmetrical claws: parities two and above and for corkscrewed claws: solid concrete alleys. The prevalence of lameness in heifers was low, however 29% had one or more claw lesions. Heifers that were housed in pens or free stalls had more heel-horn erosions, haemorrhages of the sole and white-line fissures than heifers in tie stalls. As new free stalls are being built, it is important to optimise the conditions for claw health. 相似文献
994.
Saker KE Remillard RL 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(4):291-302
Two canine studies evaluating the effectiveness of a specific computerized weight reduction program in two different clinical settings are summarized to give an overall assessment of an obesity management software program. The weight loss program utilizes a low calorie food formulation (dry, canned and treat) and software to suggest daily calorie intake for weight loss. The software utilizes current body weight and a desired weekly rate of weight loss to predict the dog's body weight in 30 days. The dietary product and software were used in a 3- and 6-month weight loss regime for 60 overweight adult dogs in two different clinical settings. On average, the dogs in this summary lost 0.75% per week regardless of more aggressive rates set by the nutritionist. Accuracy in predicting future weights by the software was dependent upon the desired rate of weight loss selected, the equation used to estimate maintenance energy requirement, and owner compliance. Over time, accuracy in predicting future canine weights improved. All healthy, overweight or obese dogs summarized in these two studies did lose weight and reached an optimal or at least lower body condition score with the aid of this software program and diet. 相似文献
995.
OBJECTIVE: To evaluate biochemical analytes in vitreous humor collected after death in West Indian manatees (Trichechus manatus latirostris). DESIGN: Prospective study. ANIMALS: 73 West Indian manatees of various ages and both sexes. PROCEDURE: The condition of manatee carcasses submitted for routine postmortem examination was categorized as fresh, moderately autolyzed, or severely autolyzed. The eyes were removed, frozen for shipping, and thawed on arrival at the laboratory. Vitreous humor was extracted, and various biochemical analytes were measured. Values for each analyte were compared with published reference ranges for corresponding biochemical analytes in serum. Values were also compared among the carcass condition groups. RESULTS: Creatinine and urea nitrogen concentrations in vitreous humor were significantly higher in severely autolyzed carcasses than in fresh carcasses. Potassium concentrations in vitreous humor were significantly higher in moderately autolyzed carcasses than in fresh carcasses but were highly variable in severely autolyzed carcasses. These data were consistent with those reported in other species. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that measurement of biochemical analytes in vitreous humor of manatees is feasible and has potential for assisting in the postmortem diagnosis of certain metabolic, renal, and nutritional diseases; determining severity of autolysis at time of necropsy; and determining the time of occurrence of human-induced trauma. 相似文献
996.
Canine eosinophilic granuloma (CEG) is a rare skin disease of unknown origin. It has been reported in Siberian huskies, Cavalier King Charles spaniels and occasionally in other breeds. The lesions comprise nodules or plaques, mostly localised in the oral cavity. A case of a single cutaneous nodular lesion of CEG on the eyelid of a Siberian husky is described. Complete remission was achieved with oral glucocorticoid treatment. 相似文献
997.
998.
REASONS FOR PERFORMING STUDY: Previous studies have implicated tension in the deep digital flexor tendon (DDFT) in the rotation of the distal phalanx (DP) after the breakdown of the dorsal laminae caused by laminitis. Howeveer, once the DP has rotated, the DDFT should become shorter, reducing the force it exerts on the DP. OBJECTIVE: To compare DDFT force and ground reaction forces (GRFs) in normal ponies and ponies with rotation of the DP as a sequel to laminitis. METHODS: Six normal ponies (Group 1) and 6 sound ponies with 6-13 degrees of rotation of the DP in relation to the dorsal hoof wall (Group 2) were assessed at trot using forceplate and motion analysis. The force in the DDFT was calculated by assuming that the extending moment at the distal interphalangeal (DIP) joint resulting from the GRF was equal to the flexing moment created by the force in the DDFT during the stance phase (inverse dynamics). RESULTS: In early stance, the peak DDFT force (mean+/-s.d.) in the normal ponies was 1.92+/-1.63 N/kg. However, in Group 2, the point of zero moment was palmar to the centre of rotation of the DIP joint for the first 40% of stance and hence DDFT force was zero. Force in the DDFT reached a peak of 10.00+/-3.56 N/kg at 60.7+/-5.6% of stance in Group 1 and 6.41+/-1.37 N/kg at 79.2+/-9.6% of stance in Group 2. CONCLUSIONS: DDFT force in Group 2 laminitic ponies was much reduced until late stance, when it neared normal values. POTENTIAL RELEVANCE: Further studies of ponies with rotation of the DP as a sequel to laminitis should assist farriery aimed at reducing the force in the DDFT through the breakover phase of stance to protect damaged dorsal laminae. 相似文献
999.
The lipopolysaccharide of Salmonella and other Gram negative pathogenic species has been implicated as a major virulence determinant and in this study we report the role of LPS of S. Enteritidis in the colonisation and persistent gastrointestinal infection of young poultry. The gene encoding the unique O-antigen ligase, waaL, was mutated by insertional inactivation in a well characterised S. Enteritidis strain, S1400/94. The waaL mutant, designated PCP, produced rough colonies on agar medium, did not agglutinate O9 antiserum, did not produce an LPS ladder on silver stained gels and was serum sensitive. PCP and a nalidixic acid marked derivative of S1400/94 (S1400/94 Nalr) were used to orally challenge young chicks, separately and together in competitive index experiments. At post-mortem examination of 1-day-old chicks challenged S1400/94 Nalr and PCP separately there were no significant differences in the numbers of S1400/94 Nalr and PCP bacteria in tissues sampled on days 1, 2, and 5. By day 42 after challenge S1400/94 Nalr bacteria were recovered in significantly higher numbers than PCP from the caecal contents (P < 0.001). In competitive index studies in the 1-day-old chick PCP colonised, invaded and persisted in lower numbers than S1400/94 Nalr. In 4-week-old chicks challenged separately, PCP bacteria were recovered from all tissues examined in significantly lower numbers than S1400/94 Nalr. In competitive index experiments in 4-week-old chicks, PCP was not detected at any site and at any time point. Therefore, the O-antigen of S. Enteritidis plays an important role in poultry infections although this role is less important in the newly hatched chick. 相似文献
1000.
Vinayak A Greene CE Moore PA Powell-Johnson G 《Journal of the American Veterinary Medical Association》2004,224(11):1804-7, 1788-9
A 2-year-old spayed female mixed-breed dog was referred with an 8-month history of recurrent bilateral anterior uveitis and hyphema secondary to infection with Brucella canis. Treatment with doxycycline PO and atropine and prednisone acetate topically prior to referral had failed to resolve the ocular inflammation. Successful control of ocular inflammation was achieved after initiation of treatment with gentamicin SC and ciprofloxacin and doxycycline PO. The finite indirect fluorescent antibody (IFA) titer was reduced by half, and results of an agar gel immunodiffusion (AGID) test became negative after rifampin was added to the treatment protocol. Treatment with gentamicin was eventually discontinued because of evidence of renal toxicosis and cutaneous reactions to repeated injections. Thirty-five months after initial examination of the dog, results of the AGID test were still negative, the finite IFA titer was stable, and ocular inflammation had resolved, suggesting that the ocular infection may have been eliminated. To our knowledge, this represents the first report of the successful treatment of ocular inflammation caused by B canis infection in a dog. 相似文献