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Experimental sialodacryoadenitis virus infection in severe combined immunodeficient mice
1991
Percy, D.H. | Williams, K.L. | Croy, B.A.
Mice with a severe combined immunodeficiency in B and T lymphocytes and natural killer cells (SCID-beige) were inoculated intranasally with sialodacryoadenitis (SDA) virus, a coronavirus of rats. Animals were killed at designated intervals and tissues were examined for evidence of viral infection by light microscopy and immunofluorescence microscopy. Based on these criteria, there was no evidence that these immundeficient mice were susceptible to infection with SDA virus.
Afficher plus [+] Moins [-]Use of a protected catheter brush for culture of the lower respiratory tract in horses with small airway disease
1991
Grandguillot, L. | Fairbrother, J.M. | Vrins, A.
A protected catheter brush introduced by fiberoptic bronchoscopy was used to sample the tracheal and bronchial mucosa in 28 horses with small airway disease. Tracheal and bronchial brushings were examined for the presence of fungi, aerobic and anaerobic bacteria, and a cytoiogical evaluation was also done on fluid collected by the bronchoalveolar lavage (BAL) technique. Microorganisms (bacteria and fungi) were isolated more often in tracheal brushings (53.6%) than in bronchial brushings (10.7%). Anaerobic bacteria were not isolated. Results of this study indicate that fiberoptic bronchoscopy using a protected catheter brush is an easy and practical technique to obtain minimally contaminated samples for isolation of microorganisms from the lower respiratory tract of horses. However, no association was observed between isolation of high numbers of microorganisms from the bronchi and severity of small airway disease.
Afficher plus [+] Moins [-]Histopathologic features, environmental factors, and serum estrogen, progesterone, and prolactin values associated with ovarian phase and inflammatory uterine disease in cats
1991
Lawler, D.F. | Evans, R.H. | Reimers, T.J. | Colby, E.D. | Monti, K.L.
Forty-four female American Shorthair cats with inflammatory uterine disease or infertility were evaluated. Data collected included age, month of diagnosis, housing, reproductive history, results of bacteriologic culture of uterine specimens, serum concentrations of estrogen, progesterone, and prolactin and histopathologic features of the ovaries and uterus. Histologically, the ovaries of 19 cats were dominated by active or cystic follicles, whereas 25 cats had luteal-phase ovaries. Of the 25 cats with active corpora lutea, 20 had either recently weaned litters (n = 11) without subsequent exposure to a male cat, or had been housed individually for lengthy periods (n = 9). The finding of active corpora lutea under these circumstances indicates that in queens, ovulation may occur by mechanisms not involving coitus. Prominent, active corpora lutea on the ovaries were associated with adenomatotic proliferative changes in the superficial and glandular epithelium of the uterus and with myometrial hyperplasia, compared with the uterus of cats with follicular ovaries (P < 0.01). Serum progesterone concentration greater than or equal to 1.87 ng/ml was consistently associated with luteal-phase ovaries. Serum progesterone values less than or equal to 0.15 ng/ml were consistently associated with follicular-phase ovaries. Escherichia coli was the organism most commonly isolated from uterine contents.
Afficher plus [+] Moins [-]Characterization of encephalomycarditis virus isolated from aborted swine fetuses
1991
Kim, H.S. | Christianson, W.T. | Joo, H.S.
Characteristics of 2 encephalomyocarditis virus (EMCV) isolates (MN-25 and MN-30) recovered from aborted swine fetuses were examined along with 2 other swine isolates (NVSL-MDV and NVSL-PR) and a reference ATCC strain (VR-129). All 5 EMCV isolates were found to be serologically related by cross testing, using serum neutralization and fluorescent antibody assays. Hemagglutination (HA) properties of the 5 isolates were compared, using 5 diluents. The MN-25 and NVSL-MDV strains had HA activity with guinea pig RBC in all 5 diluents, whereas MN-30, NVSL-PR, and VR-129 had HA activity only in KCl-borate buffer. The HA ability with RBC of various animal species was examined using KCl-borate diluent. All virus isolates had high HA titer (1:512 to 1:2,048) with guinea pig, rat, and horse RBC and lower HA titer (1:16 to 1:64) with sheep RBC. The MN-25 and NVSL-MDV isolates agglutinated dog RBC, whereas MN-30, NVSL-PR, and VR-strains 129 did not. Viral replication was evident in 8 of 10 cell lines tested, although infectivity titers of each virus varied by cell line used. Plaque-forming ability was similar for all 5 isolates, but plaque size was different by virus and cell culture used. Virus isolates were found to be stable after being heated at 56 C and subjected to a wide range of pH. A viral polypeptide pattern difference for all 5 isolates was not found by use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It was concluded that MN-25 and MN-30 are serologically related and have similar viral characteristics as those of previous EMCV isolates and the reference ATCC strain, although differences in HA ability could be observed.
Afficher plus [+] Moins [-]Comparison of flunixin meglumine and flurbiprofen for control of ocular irritative response in dogs
1991
Millichamp, N.J. | Dziezyc, J.
Dogs were treated with the cyclo-oxygenase inhibitors flunixin meglumine IV or flurbiprofen topically. Acute inflammation was induced in the eyes by disruption of the anterior lens capsule, using a neodymium:yttrium aluminum garnet laser. Pupil diameter and intraocular pressure were measured before and after inducing ocular inflammation. Both drugs maintained mydriasis and increased intraocular pressure in the inflamed eyes, compared with untreated controls.
Afficher plus [+] Moins [-]Effects of intra-articular administration of dimethylsulfoxide on chemically induced synovitis in immature horses
1991
Welch, R.D. | Watkins, J.P. | DeBowes, R.M. | Leipold, H.W.
The effects of intra-articular administration of dimethylsulfoxide (DMSO) on chemically induced synovitis in the middle carpal joint of 6 weanling horses were evaluated. Following aseptic collection of synovial fluid, the middle carpal joint of each forelimb was injected with 50 mg of Na-monoiodoacetate to induce synovitis. Eight days after injection, synovial fluid was obtained and the right middle carpal joints were injected with 2 ml of 40% DMSO in lactated Ringer solution. The corresponding joints of the left limb (control) were injected with 2 ml of lactated Ringer solution. Sampling and treatments were repeated on post-injection days 11 and 14, for a total of 3 treatments. Horses were visually evaluated daily for lameness and joint effusion. Synovial fluid was evaluated for color and clarity, differential and total WBC count, total protein content, and hyaluronic acid concentration. The Kaegi gait analysis system provided an objective assessment of lameness prior to inducing synovitis, again on day 7, and on day 17. At necropsy (day 17), synovial fluid, synovial membrane, and articular cartilage specimens were collected. Joint effusion was evident 12 hours after injection ofNa-monoiodoacetate in all joints. Mild lameness was evident at 24 hours; however, the lameness resolved by 72 hours. Objective assessment of lameness did not reveal significant differences between treatment or control limbs. Hyaluronic acid concentrations increased significantly (P = 0.023) above baseline values in most joints over the study period. Synovial fluid WBC counts increased significantly (P = 0.002) following Na-monoiodoacetate injection and remained significantly (P = 0.002) above baseline values throughout the study. There was a significantly greater decrease (P = 0.04) in total WBC counts between the pretreatment and final sampling period in the DMSO-treated joints, compared with the controls. Histologic evaluation of synovial membrane samples revealed a significantly less inflammatory response in 4 of 6 DMSO-treated joints, compared with that in the controls. Histochemical staining of articular cartilage did not reveal any observable difference between treated or control specimens.
Afficher plus [+] Moins [-]Use of a multivariable indexing score for hygiene variables in relation to egg production
1991
Mohammed, H.O. | Carpenter, T.E.
An indexing system for hygiene variables associated with egg production was developed by use of datacollected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm.
Afficher plus [+] Moins [-]High sulfide concentrations in rumen fluid associated with nutritionally induced polioencephalomalacia in calves
1991
Gould, D.H. | McAllister, M.M. | Savage, J.C. | Hamar, D.W.
Nine 115- to 180-kg, hay-adapted, Holstein steers were fed an experimental diet with added sodium sulfate that induces polioencephalomalacia (PEM). Five calves developed the disease. Thiamine concentrations in blood, CSF, brain, and liver were not indicative of thiamine deficiency. The odor of hydrogen sulfide in eructated rumen gas was associated with the onset of PEM. Sulfide concentrations in rumen fluid were measured 1 or 2 times a week by 2 techniques. Sulfide concentrations progressively increased in all 9 calves after the feeding of the PEM-inducing diet commenced. The highest concentrations coincided with the onset of clinical signs of PEM and were significantly higher in the calves that developed PEM than in those that did not. This suggests that PEM can result from sulfide toxicosis following excess production of sulfide in the rumen.
Afficher plus [+] Moins [-]Effects of mechanical and pharmacologic manipulations on portal pressure, central venous pressure, and heart rate in dogs
1991
Swalec, K.M. | Smeak, D.D. | Brown, J.
Central venous pressure (CVP), portal pressure (PP), and heart rate (HR) were monitored in 6 female, sexually intact, middle-age Beagles during temporary portal vein obstruction, anesthetic recovery, abdominal bandaging, and propranolol administration. Intraoperative baseline PP was 7.3 mm of Hg (+/- 1.7 SD). Portal pressure was significantly increased throughout portal vein occlusion, but returned to baseline values 2 minutes after release of the ligature. Central venous pressure was significantly decreased throughout portal vein occlusion, but did not differ significantly from baseline values 3 minutes after release of the portal vein ligature. Portal pressure increased significantly (8 +/- 3.3 mm of Hg) over baseline values after application of an abdominal bandage; however, CVP did not change significantly. During postoperative monitoring, CVP and PP did not change significantly from respective 18-hour mean postoperative values in resting dogs. At 60 and 75 minutes after surgery, heart rate was significantly increased over the 18-hour mean. Portal pressure and CVP, respectively, were significantly increased over intraoperative baseline values in the first hour and the first 8 hours after surgery. Postoperative CVP and HR were significantly correlated. Individual measurements of PP in dogs that were abdominal pressing during barking or defecation were significantly increased (9 +/- 3 mm of Hg) above measurements taken after cessation of abdominal press. Portal pressure measurements in standing dogs decreased 7.5 +/- 2 mm of Hg, compared with measurements of the same dog in lateral recumbency. Central venous pressure was inaccurate in dogs performing abdominal press. Portal pressure did not decrease significantly from baseline after injection of propranolol (2 mg/kg, IV). Central venous pressure was significantly decreased at 2.5 and 3.0 hours after propranolol injection, and HR was significantly decreased from 1 to 3.5 hours after injection. Heart rate quickly returned to normal values if the dogs became excited. After propranolol administration, significant correlations were found between PP and HR, and between CVP and HR.
Afficher plus [+] Moins [-]Quantitative urinalysis in kittens from four to thirty weeks after birth
1991
Hoskins, J.D. | Turnwald, G.H. | Kearney, M.T. | Gossett, K.A. | Fakier, N.
To evaluate renal function and obtain reference values for measurements of urinary excretion of various substances, quantitative urinalysis was performed in healthy, growing kittens from 4 to 30 weeks after birth. Endogenous creatinine clearance, 24-hour urine protein excretion, and urine protein-to-creatinine ratio were determined. Additionally, fractional excretion to creatinine clearance was calculated for calcium, inorganic phosphorus, sodium, potassium, and chloride. Mean +/- SD endogenous creatinine clearance values (range, 3.80 +/- 0.48 to 4.74 +/- 0.61 ml/min/kg) were significantly (P < 0.0001) higher in kittens 9 to 19 weeks old, compared with younger (range, 1.39 +/- 0.85 to 3.59 +/- 0.86 ml/min/kg) and older kittens (range, 2.69 +/- 0.40 to 3.46 +/- 0.37 ml/min/kg). Mean values for all kittens for 24-hour urine protein excretion (range, 2.54 +/- 1.81 mg/kg at 4 weeks to 11.39 +/- 7.61 mg/kg at 14 weeks) and for urine protein-to-creatinine ratio (range, 0.14 +/- 0.03 to 0.34 +/- 0.18) varied from week to week of age. The urine protein-to-creatinine ratio in kittens greater than or equal to 9 weeks old correlated well (R2 = 0.861) with 24-hour urine protein excretion. Urinary fractional excretion of calcium, inorganic phosphorus, sodium, potassium, and chloride in kittens varied among age groups, being significantly (P < 0.01) different for potassium and calcium in young kittens (4 to 6 weeks) and older kittens (greater than or equal to 7 weeks).
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