Bone and lean tissue changes following cranial cruciate ligament transection and stifle stabilization

Following cranial cruciate ligament transection and extracapsular stabilization, dual-energy X-ray absorptiometry was used to analyze bone mineral content and lean tissue mass in the surgical and nonsurgical legs (n=14) at 0, 2, 4, and 8 weeks, and to evaluate bone mineral content and bone mineral density (BMD) of the proximal, mid-, and distal tibia of both the surgical and nonsurgical legs (n=15) at 0, 5, and 10 weeks. There was significant loss of bone mineral content and lean tissue in the surgical leg compared to the nonsurgical leg. Significant loss in bone mineral content and BMD was detected in the tibia of the surgical leg and was most pronounced in the metaphyseal region.     

What is your diagnosis? Shoulder mass in a dog with lameness

Abstract: An adult castrated male Golden Retriever of unknown age was presented with a history of weight loss and progressive left thoracic limb lameness. On physical examination, a solid mass was palpated on the left scapula that had areas of lysis on radiographs and an area of cortical bone loss on ultrasound. Hepatomegaly, abdominal distension, and numerous intra‐abdominal soft tissue masses were also found. Fine‐needle aspirates of the scapula and several abdominal masses contained numerous free nuclei mixed with fewer individualized, intact cells that were round in shape and rarely formed small sheets. The cells had high nuclear to cytoplasmic ratios, central nuclei, coarsely stippled chromatin, 1–2 prominent nucleoli, and basophilic cytoplasm with indistinct cell borders. The cytopathologic interpretation was neuroendocrine neoplasia, either metastatic or multicentric. The dog was subsequently euthanized and based on gross and histologic findings at necropsy, a diagnosis of pheochromocytoma with multiple metastases was made. The neoplastic cells stained positive with Grimelius stain and were immunoreactive for synaptophysin and chromogranin A. Pheochromocytomas are rare tumors in dogs and uncommonly undergo distant metastasis, especially to bone.     

Legacies of organic matter removal: decreased microbial biomass nitrogen and net N mineralization in New Zealand Pinus radiata plantations

The effect of variations in organic matter removal during harvesting on microbial biomass nitrogen was determined in four Pinus radiata plantations between 9 and 17 years after harvesting. Variation in microbial biomass nitrogen with season and the response of net nitrogen mineralization to organic matter removal after 9 and 17 years were also determined at two of the sites. The microbial biomass nitrogen in the fermentation-humus (FH) layer was correlated with litter fall characteristics and did not vary with organic matter removal, but the total mass of microbial biomass nitrogen in the FH layer was significantly reduced by increased organic matter removal. The microbial biomass nitrogen in the mineral soil was decreased by increased organic matter removal and was strongly correlated with moisture content and total nitrogen concentration. The FH layer microbial biomass nitrogen did not vary with season, but mineral soil microbial biomass nitrogen varied with season at one site, probably due to increased moisture availability. Net nitrogen mineralization in the mineral soil, determined by an anaerobic incubation, was decreased by increased organic matter removal and was strongly correlated with microbial biomass nitrogen. The persistence of the significant differences in microbial biomass nitrogen and net nitrogen mineralization indicated that variations in organic matter removal during harvesting have long-term effects on soil microbial properties and activity during the life of the subsequent rotation. This has implications for the selection of harvesting techniques to promote the maintenance of site productivity and to minimise disruption to the soil biota.     

Manipulating inoculum densities of Verticillium dahliae and Pratylenchus penetrans with green manure amendments and solarization influence potato yield

We used cover crops with demonstrated efficacy against Verticillium dahliae and Pratylenchus penetrans in combination with the biocidal practice of solarization to determine the importance of targeting both organisms for managing potato early dying, an issue relevant to the search for alternatives to soil fumigation. Two experiments were conducted in commercial fields using a split-plot design with cover crop treatments of rapeseed, marigold, forage pearl millet, sorghum-sudangrass, and corn as the main plot factor and solarization as the subplot factor. Cover crops were grown and solarization applied in year one, followed by potato in year two. The main effect of solarization was significant for reduced inoculum levels of both organisms in year two and increased tuber yields. The main effect of cover crop was also significant with lower population densities of P. penetrans following the marigold and millet treatments and of V. dahliae following rape and sorghum-sudangrass. The cover crop treatments influenced yield in only one of the experiments in the absence of solarization. The combinatorial effect of cover crops and solarization resulted in a wide range of pathogen population densities. Mean soil inoculum levels were negatively related to yield for V. dahliae in experiment 1, and for P. penetrans and the P. penetrans × V. dahliae interaction in both experiments.     

Primary desmitis of the palmar and plantar annular ligaments in horses: 25 cases (1990-2003)

OBJECTIVE: To determine clinical and ultrasonographic abnormalities in horses with primary desmitis of the palmar or plantar annular ligament (PAL) and the response to treatment. DESIGN: Retrospective study. ANIMALS: 25 horses. PROCEDURE: Data collected from medical records included signalment, horse use, affected limb, severity and duration of lameness, results of diagnostic tests performed, ultrasonographic findings, treatment, and outcome. RESULTS: All horses had a prominent swelling in the region of the affected PAL, and signs of pain were evident during palpation of the swelling. In all horses, the affected PAL was thicker than normal as determined ultrasonographically. Twenty horses had hypoechoic regions in the PAL. Four horses, including 1 horse with 3 affected limbs, were treated by means of PAL desmoplasty, 9 were treated by means of PAL desmotomy, and 12 were treated with rest. Follow-up information was available for 21 horses. All 4 horses that underwent PAL desmoplasty, 4 of 7 horses that underwent PAL desmotomy, and 7 of 10 horses treated with rest alone became sound. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that primary desmitis of the PAL may be a cause of lameness in horses. Although significant differences in outcome between horses treated with rest alone versus PAL desmoplasty versus PAL desmotomy were not identified, because it is less invasive, PAL desmoplasty should be considered for treatment of horses with PAL desmitis that do not respond to conservative treatment and do not have any evidence of constriction of the digital flexor tendons.     

Control of urine marking by use of long-term treatment with fluoxetine or clomipramine in cats

OBJECTIVES: To determine whether clomipramine differs from fluoxetine in reducing feline urine marking; whether reduction of marking continues in cats treated >8 weeks; whether recurrence of marking, after abrupt drug withdrawal, is less in cats treated >8 weeks; and whether cats that are successfully treated but resume marking after drug withdrawal can be successfully treated again with the same drug regimen. DESIGN: Positive-controlled, double-masked clinical trial. ANIMALS: 22 neutered cats (2 females, 20 males) > or =1 year old with objectionable urine marking. PROCEDURE: Cats that marked vertically > or =3 times/wk were treated with fluoxetine (1 mg/kg [0.45 mg/lb], q 24 h, PO) or clomipramine (0.5 mg/kg [0.23 mg/lb], q 24 h, PO) for 16 weeks, and efficacy was compared. Recurrence of marking was determined after abrupt withdrawal of fluoxetine at 16 or 32 weeks. Reduction in marking in cats treated with fluoxetine for 8 weeks after returning to marking following drug withdrawal was compared with the initial 8 weeks of successful treatment. RESULTS: Efficacy of fluoxetine and clomipramine was similar. Treatment >8 weeks revealed increasing efficacy in reduction of marking. Return of marking after termination of fluoxetine administration occurred in most cats. Cats successfully treated initially with fluoxetine responded similarly to repeated treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Clomipramine and fluoxetine were equivalent in treating urine marking. Longer treatment increased efficacy. Most cats return to marking after abrupt drug withdrawal. A second course of treatment can be expected to be as effective as the first.     

Correlation between hepatobiliary scintigraphy and surgery or postmortem examination findings in dogs and cats with extrahepatic biliary obstruction, partial obstruction, or patency of the biliary system: 18 cases (1995-2004)

OBJECTIVE: To evaluate the usefulness of serum biochemical variables and scintigraphic study results for differentiating between dogs and cats with complete extrahepatic biliary obstruction (EHO) and those with partial EHO or patent bile ducts. STUDY DESIGN: Retrospective case series. ANIMALS: 17 dogs and 1 cat. PROCEDURE: Animals that underwent hepatobiliary scintigraphy and had either surgical or postmortem confirmation of the degree of bile duct patency were included. Scintigraphic images were evaluated and biliary tracts were classified as patent, partially obstructed but patent, or obstructed. Surgery or postmortem examination was considered the gold standard for diagnosis, and compared with those findings, sensitivity and specificity of scintigraphy were calculated. RESULTS: With absence of radioactivity in the intestinal tract as the diagnostic criterion for EHO, the sensitivity and specificity of scintigraphic diagnosis were both 83% when final images were acquired at 19 to 24 hours, compared with 100% and 33%, respectively, when 180 minutes was used as the cutoff time. Animals with partial biliary obstruction had less intestinal radioactivity that arrived later than that observed in animals with patent biliary tracts. CONCLUSIONS AND CLINICAL RELEVANCE: Animals in which intestinal radioactivity has not been observed after the standard 3 to 4 hours should undergo additional scintigraphic imaging. Findings in animals with partial biliary obstruction include delayed arrival of radioactivity and less radioactivity in the intestine. Distinguishing between complete and partial biliary tract obstruction is important because animals with partial obstruction may respond favorably to medical management and should not be given an erroneous diagnosis of complete obstruction.