Clinical and pathologic comparison of acute leptospirosis in dogs caused by two strains of Leptospira kirschneri serovar grippotyphosa

OBJECTIVE: To develop a method for inducing acute leptospirosis in dogs. ANIMALS: 31 nine-week-old female Beagles. PROCEDURE: Beagles were randomly assigned to 2 inoculation groups or a control group. Dogs were inoculated on 3 successive days by conjunctival instillation of 5 x 10(7) cells of Leptospira kirschneri serovar grippotyphosa strain 82 (12 dogs) or strain RM 52 (14 dogs). Control dogs (n = 5) were similarly inoculated with sterile leptospiral culture media. Clinical signs, clinicopathologic variables, anti-leptospiral antibody titers, and evidence of leptospires in tissues and body fluids were evaluated. Dogs were euthanatized and necropsied on days 7, 14, 22, or 28 after inoculation or as required because of severe illness. RESULTS: Clinical signs in infected dogs included conjunctivitis, lethargy, diarrhea, dehydration, vomiting, and icterus. Consistent clinicopathologic alterations included azotemia, hyperphosphatemia, increased anion gap, hyperbilirubinemia, and an increase in alkaline phosphatase activity. Leptospires were cultured from the kidneys (11/12), urine (6/9), aqueous humor (9/12), blood (12/12), and liver (12/12) of dogs inoculated with strain 82. Only 3 of 14 dogs became infected after inoculation with strain RM 52. Histopathologic lesions in infected dogs included interstitial nephritis, renal tubular degeneration and necrosis, pulmonary hemorrhage, and hepatic edema and perivasculitis. CONCLUSIONS AND CLINICAL RELEVANCE: Conjunctival exposure to L kirschneri serovar grippotyphosa strain 82 resulted in acute leptospirosis in all inoculated dogs, but only 3 of 14 dogs inoculated with strain RM 52 became infected. This method of infection by serovar grippotyphosa can be used to study the pathogenesis and prevention of leptospirosis in dogs.     

Effects of long-term administration of enalapril on clinical indicators of renal function in dogs with compensated mitral regurgitation

OBJECTIVE: To determine the effect of long-term administration of enalapril on renal function in dogs with severe, compensated mitral regurgitation. DESIGN: Randomized controlled trial. ANIMALS: 139 dogs with mitral regurgitation but without overt signs of heart failure. PROCEDURE: Dogs were randomly assigned to be treated with enalapril (0.5 mg/kg [0.23 mg/lb], PO, q 24 h) or placebo, and serum creatinine and urea nitrogen concentrations were measured at regular intervals for up to 26 months. RESULTS: Adequate information on renal function was obtained from 132 dogs; follow-up time ranged from 0.5 to 26 months (median, 12 months). Mean serum creatinine and urea nitrogen concentrations were not significantly different between dogs receiving enalapril and dogs receiving the placebo at any time, nor were concentrations significantly different from baseline concentrations. Proportions of dogs that developed azotemia or that had a +/- 35% increase in serum creatinine or urea nitrogen concentration were also not significantly different between groups. Conclusions: And Clinical Relevance: Results suggest that administration of enalapril for up to 2 years did not have any demonstrable adverse effects on renal function in dogs with severe, compensated mitral regurgitation.     

Chronic splenic torsion in a dog with an accessory spleen

A 4-year-old, neutered male, mixed breed Old English sheepdog was presented for evaluation and treatment of anorexia, vomiting, and diarrhea. Presumptive severe pancreatitis was diagnosed based on the referral bloodwork. Abdominal ultrasonography identified a suspected liver lobe torsion based on the presence of a normal spleen. However, an exploratory laparotomy identified a splenic torsion in addition to a grossly normal spleen.Key clinical message:This case demonstrates that a second, potentially large area of splenic tissue (ectopic or accessory) can be present in the dog; therefore, the presence of a normal appearing spleen on abdominal ultrasonography does not rule out splenic torsion.     

DIAGNOSTIC ACCURACY OF TESTS BASED ON RADIOLOGIC MEASUREMENTS OF DOGS AND CATS: A SYSTEMATIC REVIEW

A systematic review of diagnostic tests based on radiologic measurements of structures in dogs and cats was done in order to reach generalizable conclusions about the value of making such measurements. Literature search was done using the ISI Web of Knowledge^SM for studies in the subject category Veterinary sciences. Studies were eligible for inclusion that employed length, angle, area or volume measurements from radiographic, ultrasonographic, CT or MR images of dogs or cats as a diagnostic test for a naturally occurring condition, compared the results of imaging with a reference standard, included at least 10 subjects, and sufficient data that a 2 × 2 table of results could be constructed. Quality of studies was assessed using the QUADAS‐2 tool. Twenty‐six studies were found describing 40 tests that satisfied the inclusion criteria. Tests were radiographic in 22 (55%) instances and ultrasonographic in 18 (45%). Quality of studies was generally low, with a risk of bias in patient selection in 92% studies, performance of the index test in 73% studies, and patient flow in 42% studies. Median (range) number of subjects was 64 (20–305), sensitivity was 77% (38–99%), specificity was 82% (50–99%), positive likelihood ratio was 4.1 (1–103), and negative likelihood ratio was 0.29 (0.01–1). Two studies that compared accuracy of radiographic measurements to subjective image interpretation alone found no difference. Evidence is weak that radiologic measurements of structures in dogs and cats are useful for diagnosis, hence measurements should not be emphasized as a basis for diagnosis in either teaching or clinical imaging reports.     

Seroprevalence of Neospora caninum antibodies and its consequences for reproductive parameters in dairy cows from Dakar–Senegal,West Africa

The aim of this study was to determine the seroprevalence of Neospora caninum antibodies and its effects on reproductive parameters in cows in intensive dairy herds in Dakar. Randomised blood samples were taken for serology from 196 cows in four herds with a history of sporadic abortion. All of the sera were assayed for antibodies against N. caninum, Candida guillermondii, Coxiella burnetii, and Chlamydophila sp. The associations between serostatus and reproductive parameters (abortion, number of inseminations to conception, and calving to conception interval) were assessed over a period of 5 years (2004–2008). The seroprevalence of N. caninum antibodies in dairy cattle was 17.9%. The local Gobra breed and crossbreeds had higher levels of N. caninum antibodies than exotic breeds (p < 0.05). For the most recent pregnancies, seropositive cows required more inseminations to establish conception than seronegative cows (p < 0.05). The results indicate that dairy cattle from Dakar are exposed to N. caninum. Neosporosis should, therefore, be systematically considered as a cause when the calving to conception interval is prolonged.     

Influence of combined angiotensin-converting enzyme inhibitors and spironolactone on serum K, Mg, and Na concentrations in small dogs with degenerative mitral valve disease

ObjectiveTo determine if the administration of an angiotensin-converting enzyme inhibitor (ACEI) plus spironolactone caused hyperkalemia, hypermagnesemia, or hyponatremia in elderly small dogs with degenerative mitral valve disease (MVD).BackgroundACEIs and spironolactone can increase serum potassium and magnesium concentrations and lower serum sodium concentrations. It has been recommended to either not combine these drugs or to do so with caution.Animals, material and methodsFifty client-owned dogs with MVD, left atrial dilation, and without congestive heart failure or azotemia were evaluated retrospectively. Baseline data sets, followed by 1–9 (mean = 2.66) data sets, comprised of serum urea nitrogen (SUN), creatinine, sodium, potassium, and magnesium concentrations, were tabulated. Each dog received an ACEI plus spironolactone for a mean of 23.8 ± 26.6 weeks (range: 2–150) and a median of 15 weeks. No cardiac drugs other than an ACEI and spironolactone were administered during the study period.ResultsThere were no significant differences between baseline and follow-up serum sodium or potassium concentrations. Serum magnesium concentrations increased significantly (p = 0.02) with time >20 weeks compared to baseline.ConclusionsThe combination of an ACEI and spironolactone results in no significant difference between baseline and follow-up serum sodium or potassium concentrations. Although serum magnesium concentrations may increase significantly with time >20 weeks compared to baseline concentrations, hypermagnesemia appears to be rare, mild, and unlikely to be of clinical importance. The combination of an ACEI and spironolactone is safe in elderly small dogs with MVD with normal SUN and creatinine concentrations.     

Agronomic performance and genetic progress of selected historical soybean varieties in the southern USA

This study was conducted to compare recently developed and historical soybean varieties and evaluate genetic gain in yield and other agronomic traits in the southern USA. A total of 45 southern varieties from public breeding programs, which were released from 1928 to 2008, were used in this study. Three experiments were conducted in 2007 and 2008 at Keiser, Stuttgart, and Marianna in Arkansas (USA). Varieties with maturity groups (MG) late IV to early V had a yield gain of 21.7 kg/ha/yr from the 1950s to the 2000s, mid to late MG V had a yield gain of 16.4 kg/ha/yr from the 1940s to the 2000s, and MG VIs had a yield gain of 12.4 kg/ha/yr from the 1920s to the 2000s. Yield increased linearly for all combined experiments by 16.8 kg/ha/yr. Plant height remained steady over time for most experiments. No significant changes were observed in maturity. Lodging scores decreased, protein concentration decreased, and oil concentration increased linearly over time for all combined experiments. Hutcheson, Narrow, R97‐1634, and Young were recommended as parent lines in future soybean breeding efforts.