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941.
The records of 71 horses with small intestinal disorders requiring surgical correction were disorders requiring surgical correction were reviewed to compare the prevalence of laminitis in those horses treated prophylactically with heparin and the prevalence of horses not treated with heparin. The prevalence of laminitis was 13% (9/71), and there was no significant difference (P less than 0.05) in the prevalence of laminitis between the 2 groups. The lack of significant benefit after treatment with heparin indicates that further work needs to be done on the equine coagulation system before heparin can be advocated for prevention of laminitis. 相似文献
942.
Trees and saplings of all sizes (total 229) were studied atthree amenity sites in Surrey representing mixed woodland, beechhigh forest and open parkland. Roloff's winter assessment ofthe twig pattern of growth demonstrated an underlying differencebetween the sites, which was consistent with an associationbetween greater deterioration and more exposure to climate extremesand pollutants. Trees showed deterioration with age but prematureageing was seen in 3550-year-old parkland trees. Withinthe woodland the more exposed trees had worse scores. Quantitative twig analysis was carried out on twigs from theupper canopy of 19 trees and saplings. In the most severelysuppressed trees yearly growth declined from the 1976 drought.Subsidiary shoot development was markedly reduced in such treesand there were high numbers of distorted and acute angled shoots.The latter two characteristics increased with age with younghealthy trees having very few of these types of shoots, buttwo 35-year-old trees in open parkland showed premature ageingwith larger numbers of such shoots. Twig analysis defined categories of twig pattern according toage and deterioration levels. There was generally good correlationbetween these categories and the Roloff twig canopy score beforeanalysis or with canopy scores of similar sized neighbours.Objective criteria suggested for future studies were: (1) measurementof annual primary shoot growth; (2) total secondary shoot lengthrelative to a standard primary shoot length; (3) mean numberof subsidiary shoots per year; and (4) proportion of shootsgrowing at 40° or less. 相似文献
943.
Between July 1985 and April 1986, mycobacterial lymphadenitis was recorded in six of 2407 slaughter pigs from a commercial swine herd in which the majority of pigs were raised in confinement. Records showed that all six affected pigs had access to dirt-floored pens at least 81 days prior to slaughter. The mycobacteriosis lesion rate for pigs exposed to dirt pens was 9.4% while in nonexposed pigs the lesion rate was zero. The risk associated with movement of pigs from concrete floored pens to dirt pens was evaluated by a field trial. In the field trial, two litters (5 of 15 pigs) exposed to dirt pens at 12-24 days of age but none of nine nonexposed litters (39 pigs) developed lesions. Mycobacterium avium-complex bacteria were recovered from both exposed litters (9 of 15 pigs) but from none of nine nonexposed litters. Serovars of M. avium-complex isolated from trial pigs included 1, 4, 8, 9, the dual serovar 4/8, and an untypable serovar. Incense-cedar bark (Calocedrus decurrens) used as a flooring material in the pens was demonstrated to be a potential source of M. avium-complex serovar 9. The dual serovar 4/8 and an untypable M. avium-complex were isolated from the dirt-floored pens. No evidence of cross-transmission of M. avium-complex infection was detected. The sporadic pattern of mycobacteriosis observed in the herd probably resulted from infrequent exposure to a common environmental source. 相似文献
944.
Cefuroxime pharmacokinetics were studied in unweaned calves. The antibiotic was administered at 10 mg/kg to six calves i.v., to 12 calves i.m. and to ten of the previous 12 calves i.m. at 10 mg/kg together with probenecid at 40 mg/kg. Intramuscular doses of cefuroxime alone at 20 mg/kg were given to seven calves; to five of these calves cefuroxime was also given together with probenecid at 40 mg/kg and at 80 mg/kg. The serum concentration-time data were analyzed using statistical moment theory (SMT). The elimination half-life (t1/2) was 69.2 min (harmonic mean) after i.v. and 64.8 min and 64.9 min following i.m. administration of the lower and higher dose, respectively. Co-administration of probenecid did not affect the t1/2. The mean residence time (MRT) was 80.9 +/- 23.5 min (mean +/- SD) after i.v. and 117.8 +/- 9.3 min and 117.7 +/- 5.4 min after i.m. administration of cefuroxime at 10 and 20 mg/kg, respectively. The MRTi.m. following administration of cefuroxime at 10 mg/kg together with probenecid at 40 mg/kg was 140.0 +/- 8.8 min. The MRTi.m. values were 132.8 +/- 2.3 min and 150.8 +/- 5.1 min after cefuroxime was given at 20 mg/kg together with probenecid at 40 mg/kg or 80 mg/kg, respectively. The total body clearance (ClT) was 3.56 +/- 1.11 ml/min/kg and the volume of distribution at steady state (Vd(ss] 0.270 +/- 0.051 l/kg. The MIC90 values of cefuroxime were 16 micrograms/ml for E. coli and Salmonella isolates, 0.5 microgram/ml for Pasteurella multocida and 2.0 micrograms/ml for P. haemolytica. 相似文献
945.
H J Bengelsdorff 《Berliner und Münchener tier?rztliche Wochenschrift》1989,102(6):193-198
In the course of vaccine controls, the potency of 25 foot-and-mouth disease (FMD) vaccines was tested quantitatively in parallel in cattle using the intradermal infection and the determination of the SN titres. More than 95% of the vaccinated cattle with SN titres of greater than 1:20 were protected from generalized FMD, regardless of the virus type tested. 61.5% of the vaccinated cattle with SN titres less than or equal to 1:20 were not protected and developed generalized FMD. Comparison of the PD50 values calculated from the results of the intradermal infection and the corresponding SN titres (minimum protection titre greater than 1:20) showed that the results were in complete agreement in 56% of the tested vaccines. In a further 32% of vaccines, the PD50 calculated from the SN titre was slightly below that for the intradermal infection, in the remaining 12% it was somewhat above. The possibility of using the minimum titre determination for testing a vaccine and the significance of this titre as an expression of protection by vaccination are discussed. 相似文献
946.
Oesophagogastric parakeratosis in the growing pig: effects of the physical form of barley-based diets and added fibre 总被引:1,自引:0,他引:1
In four experiments a total of 288 individually fed pigs were given barley-based diets for about 100 days from about 20 kg liveweight. Fine grinding of barley increased the number and severity of oesophagogastric lesions. Pelleting a diet based on coarsely ground barley had a similar effect. Coarser grinding of the barley and substituting small proportions of oat husk, but not of bran, gave lower incidences and severities of lesions. The performance responses of the pigs differed and give a framework for deciding on the balance to be struck between optimal performance and the risk of lesion development. 相似文献
947.
948.
949.
A review of investigations of the functional anatomy of the equine foot is presented. Emphasis is placed on the relationships of structures involved in the major diseases of the foot. 相似文献
950.
The management of guttural pouch mycosis 总被引:1,自引:0,他引:1
J G Lane 《Equine veterinary journal》1989,21(5):321-324