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991.
Uncinaria stenocephala hookworm dermatitis (uncinariosis) was diagnosed on fecal examination and macerated skin biopsy in a 1.5-year-old greyhound dog from Saskatchewan. This is the first reported case in Canada. Treatment with moxidectin cleared gastrointestinal and dermal infections.  相似文献   
992.
993.
994.
Litter was collected from four turkey farms (eight houses) with a history of fluoroquinolone (FQ) treatment failure, 10 adult broiler breeder chicken farms (43 houses) with one having a history of FQ treatment, and 30 broiler chicken farms (110 houses) with 24 having a history of FQ treatment. In the turkey litter, the percentage of nalidixic acid-resistant (at 100 microg/ml) coliforms/total number of coliforms ranged from 0.6% to 61.9%. Two of the four farms had houses containing coliforms resistant to the two FQs, enrofloxacin (1 microg/ml) and sarafloxacin (1 microg/ml). There was also multiple resistance to other antimicrobials on all four turkey farms (ampicillin, tetracycline, chloramphenicol, kanamycin). The level of total coliforms from the adult broiler breeder litter was low, and there were no nalidixic acid-resistant isolates from any of the 10 farms. In the broiler chickens, 7 of 91 houses with a history of FQ usage contained coliforms resistant to nalidixic acid; however, 2 of the 19 houses on farms with no history of FQ usage had nalidixic acid-resistant coliforms. All of the broiler farms with nalidixic acid-resistant isolates were also resistant to the FQ sarafloxacin, whereas only 3 of the 24 treatment history farms and 1 of the no-treatment history farms exhibited enrofloxacin-resistant coliforms in the litter.  相似文献   
995.
Clinical, electromyographic, and pathologic findings characteristic of lead toxicosis were detected in a turkey vulture (Cathartes aura). The bird had generalized lower motor neuron dysfunction that progressed over 5 days. Electromyography revealed diffuse denervation potentials and a presumed decrement in the sciatic-tibial nerve conduction velocity. Histologic examination of peripheral nerves obtained at necropsy revealed changes that could be compatible with lead-induced neuropathy. Lead toxicosis was confirmed by determination of blood lead concentrations. Lead toxicosis causing neurologic disorders in birds has been described. However, this report emphasizes the effects of lead on the peripheral nervous system and demonstrates the use of electromyography for diagnosis of peripheral neuropathy in birds.  相似文献   
996.
OBJECTIVE: To report the occurrence of medullary bone infarction in both femoral canals after bilateral total hip arthroplasty (THA) and the subsequent unilateral development of an osteosarcoma at the site of bone infarction. STUDY DESIGN: Clinical report. ANIMAL POPULATION: An 8-month-old neutered male Samoyed dog. METHODS: Serial physical and radiographic examinations performed at 1, 2, 3, and 5 years after THA. Bone biopsy specimens of the right distal femoral metaphysis were taken 5 years after THA, and a complete necropsy was performed at the time of euthanasia. RESULTS: Bilateral medullary bone infarction was visible in the femoral canals 1 year after THA and remained visible on subsequent evaluations. An osteosarcoma developed in the right distal femoral metaphysis at the site of infarction, 5 years after THA, and was found to have metastasized widely throughout the body. CONCLUSION: Bone infarction may occur in the femoral canal after canine THA. CLINICAL RELEVANCE: Bone infarction may be a predisposing factor for the development of osteosarcoma in the femora of dogs with THAs.  相似文献   
997.
OBJECTIVE: To evaluate the reliability of taurine concentrations measured in a single urine sample obtained from dogs 8 hours after eating, compared with taurine concentrations measured in 24-hour urine samples. ANIMALS: 18 healthy Beagles. PROCEDURE: After emptying the urinary bladder by transurethral catheterization, dogs were fed a canned maintenance diet. Approximately 8 hours later, urine, plasma, and serum samples were obtained for determination of fractional urinary excretion of taurine and urine taurine-to-creatinine concentration ratios (Utaur:Ucr). Results were compared with 24-hour urinary taurine excretion rate. RESULTS: Unbound and total fractional urinary taurine excretion correlated well with unbound and total 24-hour urinary taurine excretion. However, bound fractional urinary taurine excretion correlated poorly with bound 24-hour urinary taurine excretion. Unbound and total Utaur:Ucr correlated well with unbound and total 24-hour urinary taurine excretion. However, bound Utaur:Ucr correlated poorly with bound 24-hour urinary taurine excretion. CONCLUSION AND CLINICAL RELEVANCE: Fractional urinary excretion of unbound and total taurine, and unbound and total Utaur:Ucr are reliable indicators of 24-hour urinary unbound and total taurine excretion in healthy dogs. However, determination of 24-hour urinary taurine excretion is recommended for evaluating urinary bound taurine concentrations of dogs.  相似文献   
998.
In a report describing life ending fractures (255 horses) from the Livestock Disease Diagnostic Center, Kentucky (1993 and 1994), 32 foals had rib fractures. The purpose of our study was to examine the incidence of rib fractures in newborn foals on a Thoroughbred studfarm by physical and radiographic examination, to determine factors which may contribute to the problem and to document any clinical consequences. All foals (263) included were examined within 3 days of birth. The thoracic cage was palpated externally for abnormalities and all foals were placed in dorsal recumbency to evaluate thoracic cage symmetry. Radiographs were used to diagnose foals with thoracic cage asymmetry (TCA) and rib fracture (RF). A diagnosis of costochondral dislocation (CD) was made when no radiographic evidence of fracture was present but there was severe TCA. Fifty-five foals (20.1%) had TCA (9 RF). One to 5 ribs were fractured on 9 of 40 radiographic studies. No consequences of the thoracic trauma was detected clinically, radiographically or ultrasonographically in this group of foals or at a 2- and 4-week follow-up examination. The percentage of foals with a history of abnormal parturition was higher in the TCA foals (15%) compared to the normal foals (6.8%). There were more primiparous dams in the TCA group than in the normal foal group. Fillies (56.6%) had a higher incidence of birth trauma than colts (43.4%). This study demonstrates that thoracic trauma is often present in newborn foals and may not always be of clinical significance. Dystocia foals and foals from primiparous mares should be considered high risk for thoracic trauma.  相似文献   
999.
Heifers treated with ivermectin at weaning have been reported to reach puberty at a younger age and lighter weight than untreated heifers. We tested the hypothesis that heifers administered ivermectin would respond with earlier follicular development and a greater LH response to a 1-mg estradiol-17beta challenge (E2C) than untreated heifers. Fall-born Angus heifers (n = 32) were randomly assigned on 284 +/- 9 d of age (215.5 +/- 20.8 kg) to receive ivermectin (IVR) or albendazole (ALB), IVR + ALB, or to remain as untreated controls (CONT). Each group (n = 8) was housed separately in adjacent pens throughout the trial and managed to gain .8 kg/heifer on a ration containing 13.2% CP, 58.8% TDN, and 49.9% DM. The CONT heifers received an additional 2.27 kg/heifer of corn silage and 1.59 kg/heifer of corn daily to maintain ADG at comparable levels. Individual body weight was recorded weekly, and nematode eggs per gram (EPG) of feces were measured every 21 d. Ultrasonography was performed on alternate days starting 2 wk prior to E2C to characterize follicular wave patterns. Follicles were separated into classes (C1 [3 to 5 mm], C2 [6 to 9 mm], and C3 [10 mm]) and sizes (largest [LF], second [SLF], third [TLF], and fourth largest follicles [FLF]). The sizes of the regressing dominant follicle 1 (DF1) and the progressing dominant follicle 2 (DF2) were also determined. Serum concentrations of LH were determined from hourly jugular blood samples collected 8 to 24 h after injection of E2C. The IVR + ALB treatment group had more C3 follicles than ALB and CONT (P < .07). The IVR-treated heifers had larger TLF than ALB and CONT (P < .04). The IVR- and IVR + ALB-treated heifers had larger FLF and DF2 than ALB and CONT (P < .1). Least squares means for DF2 were 9.5 +/- .5, 8.0 +/- .4, 9.5 +/- .3 and 8.3 +/- .3 mm, for IVR, ALB, IVR + ALB and CONT, respectively (P = .02 for treatment effect). The E2C-induced serum LH concentration did not differ with respect to treatment. We conclude that heifers administered IVR display increased follicular development, supporting our earlier investigations regarding reduced age at puberty in heifers treated with IVR near weaning.  相似文献   
1000.
Cell surface hydrophobicities of streptococci of serological group B were determined by the adherence of the bacteria to hexadecane droplets. A significant adherence to hexadecane was observed with the group B streptococcal type reference strains Ib, V, Ic, R and X, but not with those of serotype Ia, II, III and IV. Cultivation of the bacteria in microcapsule-inducing media reduced the hexadecane adherence properties. The adherence to hexadecane was not related to fibrinogen binding properties of the cultures. Screening a large number of group B streptococci isolated from humans and bovines revealed that those with polysaccharide type antigen alone were generally hydrophilic, those with protein antigen alone or with protein antigen in combination with polysaccharide antigen were mostly hydrophobic. Cultivation of the bacteria under microaerobic conditions or after a single mouse passage enhanced microcapsule production and correspondingly reduced the hexadecane adherence values. Treatment of the bacteria by guanidinium chloride or by neuraminidase enhanced the hexadecane adherence. The hydrophobic component on group B streptococcal surface appeared to be partly inactivated by heat or proteolytic treatment of the bacteria.  相似文献   
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