Search Results
You are looking at 1 - 3 of 3 items for
- Author or Editor: Larry Johnson x
- Refine by Access: All Content x
SUMMARY
Three ejaculates from each of 3 stallions were used to evaluate a computerized system (Hamilton-Thorn motility analyzer; htma) for measuring equine spermatozoal motility. Variance components (ejaculate-within-stallion, chamber-within-ejaculate, and microscopic field-within-chamber) were determined for each stallion after diluting ejaculates to 25 × 106 spermatozoa/ml with a skim milk-glucose seminal extender. The htma was compared with frame-by-frame playback videomicrography (video) for determining: percentage of spermatozoal motility and spermatozoal number in microscopic fields; curvilinear velocity and straight-line velocity of individual spermatozoa for 5 track types; and repeatability of those velocity measurements. The effect of spermatozoal number per microscopic field on incidence of intersecting spermatozoa and the outcome of intersecting spermatozoa also were evaluated. Greatest variability in motility measures was generally attributed to the microscopic field-within-chamber component. The htma was highly correlated with video for estimation of spermatozoal numbers per microscopic field (r = 0.99; P < 0.001) and motility (r = 0.97; P < 0.001); however over the entire range of spermatozoal numbers, the htma yielded higher spermatozoal numbers per microscopic field (P < 0.05) and higher motility (P < 0.05) than did video. The htma- and video-derived measurements of curvilinear and straight-line velocities were highly correlated for all spermatozoal track types, but both measures were higher (P < 0.05) by use of the htma than by use of video for most track types. For 3 of 5 track types, measurements of curvilinear and straight-line velocities were less variable (P < 0.05), using the htma, rather than video. Using the htma, the number of intersecting spermatozoa was highly correlated with spermatozoal numbers per microscopic field (r = 0.97; P < 0.001). The percentage of erroneous track interpretations involving intersecting spermatozoa was high (85.3 ± 2.7%). The htma was a reliable system for determining percentage of spermatozoal motility and velocity measures in video recordings of equine semen diluted to spermatozoal concentration of 25 × 106/ml prior to evaluation.
Abstract
OBJECTIVE
To determine whether ultrasonographic features in dogs with protein-losing nephropathy (PLN) were associated with renal biopsy findings and compare corticomedullary ratios between dogs with PLN versus non-renal disease.
ANIMALS
71 dogs with PLN and 33 dogs without renal disease.
PROCEDURES
Medical records and archived ultrasonographic images for dogs with PLN that underwent renal biopsy between 2008 and 2018 were reviewed. Corticomedullary ratios were measured.
RESULTS
In dogs with PLN, median serum creatinine and BUN concentrations and urine-protein-to-creatinine-ratio prior to renal biopsy were 3.4 mg/dL (interquartile range [IQR], 1.2 to 5.3 mg/dL), 80 mg/dL (IQR, 28 to 105 mg/dL), and 11.4 (IQR, 6.4 to 18.3), respectively. Histologic abnormalities within the tubulointerstitial space were associated with cortical echogenicity. Gastric wall thickness > 5 mm was associated with a histologic diagnosis of acute glomerular disease. Dogs with immune complex–mediated glomerular disease were more likely to have abnormal gastric mural architecture. Other ultrasonographic features of the kidneys, liver, and stomach and the presence of ascites did not help to differentiate immune complex–mediated from non-immune complex–mediated glomerular disease, acute from chronic disease, or amyloid from non-amyloid disease or distinguish whether tubulointerstitial disease was present or absent. Median left corticomedullary ratio for 66 dogs with PLN (1.2) was significantly higher than that for the 33 dogs without renal disease (1.0).
Clinical Relevance
Ultrasonographic features were poorly associated with specific pathological disorders in dogs with PLN. In this study, the corticomedullary ratio was higher in dogs with PLN, indicating the presence of cortical thickening, but the clinical relevance is unknown.
Abstract
Objective
To evaluate fecal shedding of Cryptosporidium parvum from California cow-calf herds with respect to age, geographic region, temporal effects, and association with watery feces.
Animals
Cows and calves from 38 beef cow-calf operations.
Procedure
Fecal specimens were collected and examined for C parvum oocysts, using immunofluorescent microscopy. Associations between age, geographic region, month of collection, watery feces, and likelihood of shedding C parvum were evaluated.
Results
3.9% of cattle were shedding C parvum oocysts. Prevalence of shedding among calves ranged from 0 to 13%, and was 0.6% among cattle ≥ 12 months old. The odds of shedding C parvum among 2-month-old calves were 41 times greater than among cattle > 4 months old. The odds of shedding C parvum among cattle tested in May were 8.7 times greater than among cattle tested during June, July, or August. The odds of infected individuals having watery feces were 3 to 4 times greater than for noninfected individuals, but the etiologic fraction was only 8 to 9%.
Conclusions and Clinical Relevance
Substantial fecal shedding of C parvum by cow-calf herds was limited to calves 1 to 4 months old, with low prevalence detected in older animals. Risk of contamination of watersheds with C parvum was limited to those periods when young calves were in the herd. Although the odds of having watery feces were greater for animals infected with C parvum than for noninfected animals, the low etiologic fraction suggests that most calves with watery feces were not infected with C parvum. (Am J Vet Res 1999;60: 420-425)
