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21.
Four hundred and seventeen Canadian veterinarians were surveyed to determine their postoperative use of analgesics in dogs and cats following 6 surgical procedures, and to determine their opinions toward pain perception and perceived complications associated with the postoperative use of potent opioid analgesics. Three hundred and seventeen (76%) returned the questionnaire. The percentage of animals receiving analgesics postoperatively ranged from 84% of dogs and 70% of cats following orthopedic surgery to 10% of dogs and 9% of cats following castration. In general, with the exception of orthopedic surgery, roughly equal percentages of dogs and cats received postoperative analgesics. Opioids were used almost exclusively to provide postoperative analgesia, with butorphanol the most commonly administered drug to both dogs and cats. Analgesics were usually administered either once or twice postoperatively. With regard to the administration of potent opioid agonists, the 3 major concerns included respiratory depression, bradycardia, and sedation in dogs, and excitement, respiratory depression, and bradycardia in cats. Seventy-seven percent of veterinarians considered their knowledge of issues related to the recognition and control of postoperative pain to be inadequate. Experience in practice is currently the major source of knowledge, with undergraduate veterinary school and research articles in journals ranked as the least important sources. Lectures or seminars delivered at the regional level were the preferred format for continuing education.  相似文献   
22.
The effects of maedi-visna virus infection on productivity in ewes   总被引:1,自引:0,他引:1  
A total of five data sets obtained from four separate sheep flocks were used to evaluate the effects of subclinical maedi-visna virus infection (as determined by serological procedures) on productivity in ewes. In general, infection with maedi-visna virus had a detrimental effect on productivity. Infection resulted in a reduction in conception rates, with the odds of an infected ewe conceiving being only approximately 0.67 times those of a non-infected ewe. For ewes which did conceive, there was no detrimental effect of infection on the number of lambs born. The birth weights of lambs born to middle-aged (3–4 years) infected ewes were 3–6% lower than the weights of lambs born to non-infected ewes of the same age. There was very little apparent effect of infection in younger (1–2 years) and older (5 + years) ewes: some factors which may have biased these results are discussed. Lamb weights at 25–50 days of age appeared to be reduced by maedi-visna infection in the ewe but the results were not statistically significant.  相似文献   
23.
An equine abuse policy was developed as an adjunct to an equine management survey. If at least 3 of 5 categories caused concern, a report to the authorities was indicated. The policy was not used but, in the absence of other guidelines, it might assist veterinarians considering potential abuse cases.  相似文献   
24.
The objective of this study was to assess the stability of ELISA plates prepared with one of three blocking agents and used with one of two conjugates at various time intervals after preparation of the plates. Two of the blocking agents used were commercially available: one termed stabilgaurd (stab) and one manufactured by SVANOVA Biotek AB Inc. (svan). The third blocking agent used was bovine serum albumin (bsa). A polyclonal rabbit anti-bovine IgG (poly) and an anti-bovine IgG monoclonal (mono) conjugate were used. Eighteen composite individual cow milk samples collected late in lactation (200-400 days in milk) were used in this study. An indirect microtitre plate ELISA that used the Ostertagia ostertagi antigen was used to quantify antibodies against the parasite, present in the milk samples. Each of six blocking agent/conjugate combinations (called systems) were used to test 18 milk sub-samples at 1, 4 and 24 weeks after blocking the plates. Plates blocked with stab and svan were kept at room temperature and an additional set were incubated at 37 degrees C so as to mimic long term storage (about 1 year) and tested only once at 4 weeks. Those blocked with bsa were frozen at -20 degrees C. Concordance correlation coefficients (CCC) and reproducibility were used to assess the agreement between test results conducted on the same milk sample at the various test-times using a particular system. Generally, there was good agreement between tests conducted at different times for all systems. However, the svan-mono and bsa-poly systems had the best agreement with overall CCC values of 96% and 93%, respectively. The svan-poly system had the lowest CCC of 75%. The CCC and reproducibility ranked the systems in a similar way. The high CCC between tests done using plates kept at room temperature and ones incubated at 37 degrees C, suggested that plates would be stable up to a year after blocking. The storage of plates blocked with svan and stab agents under room temperature, makes them more convenient to use and transport relative to bsa-blocked plates that have to be frozen.  相似文献   
25.
The objective of this study was to determine the agreement between ELISA tests conducted using three O. ostertagia antigens: crude adult worm, larval stage 4 (L4) excretory/secretory (ES) and adult ES. This study was carried out on 289 Holstein cows from five herds in Prince Edward Island and one herd in Nova Scotia. Composite milk samples of these cows were collected (between May and September 2002) from the respective provincial laboratories and sent to the Atlantic Veterinary College where each sample was tested for antibodies to O. Ostertagi using an indirect microtitre ELISA test. Results were expressed as optical density ratio (ODR) values. Each milk sample was tested with three ELISA tests, with each test using a different O. ostertagi antigen. There was a slight rise in ODR values of both adult antigens, between May and August, with higher values obtained using the adult ES antigen. L4 ES ODR values were generally higher than those for both adult antigens during the study period, except for May. There was a more dramatic rise in L4 ES ODR values between May and August. Rises in ODR in May and end of July coincided with periods of mass maturation of L4 to adult worms. The results of the study showed that the concordance correlation coefficient (CCC) between tests performed using both ES and the crude antigens were low (crude adult versus adult ES=0.31, crude adult versus L4 ES=0.30). The highest CCC was observed between tests done using both ES antigens (CCC=0.56). Generally, the study results suggest that the antibody response (detectable by the ELISA) is mainly directed against ES antigens (especially L4) than the crude adult worm antigen.  相似文献   
26.
Infectious salmon anemia (ISA) is a viral disease occurring in farmed Atlantic salmon (Salmo salar) that is characterized by lethargy, anorexia, anemia and death. To control the disease in New Brunswick, Canada, 7.5 million fish from outbreak cages have been destroyed since 1997. Despite changes made by farmers, 2002 was the worst year ever for ISA losses in the region.

We evaluated the associations between potential risk factors and ISA outbreaks in the Atlantic-salmon sites in New Brunswick. This was a multilevel study in which the site-level design was a retrospective cohort study while the cage-level design was a modified case-cohort study. The questionnaire was divided into site-level questions, cage-level questions and hatchery information.

The important factors identified by this study can be categorized as environmental, farmer controlled or industry controlled according to the capacity to change or eliminate them. Environmental risk factors such as increasing the depth of the net (if nets were ≤9 m, odds ratio (OR) = 3.34) and decreasing the depth of water underneath the net (if depth of water underneath the net >3 m, OR = 3.34) are for the most part dictated by site location. Wild pollock (Pollachius virens) in the cage reflects the number of wild pollock that live in the site location. If there were ≥1000 pollock in the cage, the odds of disease in the cage increased 4.43-fold. Risk factors that are under farm control include increasing the number of times that the salmon are treated for sea lice (OR = 3.31 if lice treatments are ≤2 times), transferring small smolts into seawater (OR = 2.40 if smolts weighed >99 g) and improving on the adaptation of smolts to seawater to reduce post-transfer mortalities (OR = 4.52 if there was at least one cage with post-transfer mortalities >5%). The industry-controlled factors need to be addressed by the industry as a whole. Organizing boat travel to minimize the time and frequency of boats travelling to or by sites currently is being reviewed. This will be extremely important because the OR = 9.43 if processing boats travel within 1 km of the site and the OR = 4.03 if the site has dry feed delivered by the feed company. Because the hazard ratio increased stepwise from 1 if the nearest neighbor with ISA was ≥5 km up to 5.5 if the nearest site with ISA was within 0.5 km, increasing the distance between sites might be necessary for effective control.  相似文献   

27.
The present study was carried out to evaluate the relationship between milk optical density ratios (ODRs) from an indirect Ostertagia ostertagi ELISA, total milk IgG levels and milk production and then establish a correction factor to adjust ODR. Five hundred and sixty composite milk samples collected from 358 cows on four dairy herds in June and August 2002 were used in this analysis. The average ODR was 0.34. A positive correlation was found between ODR and IgG values in milk, days in milk, age and log transformed somatic cell counts (SCC). However, ODR was negatively correlated with milk production. The IgG levels and ODR values were constant from 30 to 200 days in milk. However, ODRs increased from 200 days until the end of the lactation. After controlling for age, season, herd and SCC, an increase in milk production of 13 kg/day was associated with a reduction in ODR values of 0.052. The results of the present study suggest that ODR values are not greatly influenced by production factors. ODR follow the same pattern as the IgG variation across lactation and could be adjusted in order to compare ODR values obtained from high producing cows with those obtained from low producing animals.  相似文献   
28.
In North America, there are few representative data about the effects of management practices on equine welfare. In a randomized survey of 312 nonracing horses in Prince Edward Island (response rate 68.4%), owners completed a pretested questionnaire and a veterinarian examined each horse. Regression analyses identified factors affecting 2 welfare markers: body condition score (BCS) and stereotypic behavior. Horses' BCSs were high (mean 5.7, on a 9-point scale) and were associated with sex (males had lower BCSs than females; P < 0.001) and examination date (P = 0.052). Prevalences of crib biting, wind sucking, and weaving were 3.8%, 3.8%, and 4.8%, respectively. Age (OR = 1.07, P = 0.08) and hours worked weekly (OR = 1.12, P = 0.03) were risk factors for weaving. Straw bedding (OR = 0.3, P = 0.03), daily hours at pasture (OR = 0.94, P = 0.02), and horse type (drafts and miniatures had a lower risk than light horses; P = 0.12) reduced the risk of horses showing oral stereotypies. Some of these results contradict those of other studies perhaps because of populations concerned.  相似文献   
29.
A random sample of 652 Canadian veterinarians was surveyed to determine perioperative use of analgesics in dogs and cats following common surgeries. The response rate was 57.8%. With the exception of taildocking in puppies, at least 85% of animals received preincisional analgesics, and 30% to 98.1% received postincisional analgesics. A similar survey was conducted in 1994; since then, analgesic usage has increased markedly, as have ratings of the pain caused by different surgeries. In 2001 most veterinarians (62%) used at least 2 classes of analgesic perioperatively. However, strong opioids, local anesthetics, and alpha-2 agonists were underused, and there was an overreliance on weak opioids (butorphanol, meperidine). Up to 12% of veterinarians did not use any analgesics. Nationally, this may have affected many animals monthly; for example, approximately 6000 dogs or cats undergoing ovariohysterectomy. Continuing education (provincial level) and review articles were considered effective ways to inform veterinarians about optimal analgesic practices.  相似文献   
30.
OBJECTIVE: To determine whether insertion of an internal teat sealer (ITS) at the end of lactation would prevent development of new intramammary infections (IMIs) during the nonlactating period. DESIGN: Controlled clinical trial. ANIMALS: 939 Holstein-Friesian dairy cows from 16 herds. PROCEDURES: Results of bacteriologic culture of milk samples collected 14 days prior to the end of lactation were used to assign cows to groups (group 1 = negative results for all quarters; group 2 = positive results for > or = 1 quarter). Quarters of cows in group 1 were treated with an ITS or a single intramammary dose of cloxacillin; quarters of cows in group 2 were treated with cloxacillin in conjunction with an ITS or with cloxacillin alone. Milk samples were collected at the end of lactation and within 8 days after calving. RESULTS: Regardless of whether the outcome of interest was new IMIs caused by any pathogens, major pathogens, environmental pathogens, or streptococci other than Streptococcus agalactiae, quarters in group 2 treated with both cloxacillin and an ITS were less likely to develop a new IMI than were quarters treated with cloxacillin alone. For cows in group 1, no significant difference in risk of new IMIs was found between treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that for dairy cattle with an IMI late in the lactation period, intramammary administration of cloxacillin at the end of lactation followed by insertion of an ITS enhanced protection against development of new IMIs, compared with use of cloxacillin alone.  相似文献   
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