Anterior uveitis as an atypical presentation of large granular lymphoma in a caracal (Caracal caracal)

An 11-year-old, female, spayed caracal (Caracal caracal) presented with a 3-month history of intermittent anorexia, vomiting, and weight loss. At examination, bilateral anterior uveitis with anisocoria was present. Further examination under general anesthesia revealed the anterior chamber of the right eye contained copious amounts of thick fibrin, hypopyon, and hyphema obscuring the ventral pupil margin and ventral iris. Aqueous paracentesis revealed a cytologic diagnosis of large granular lymphoma. Additional antemortem diagnostics (computed tomography, ultrasound with fine needle aspiration, and cytology) confirmed the diagnosis of multicentric large granular lymphoma with associated intestinal perforation. Necropsy and histopathology confirmed multicentric large granular lymphoma in the right eye, jejunum, mesenteric lymph nodes, and right kidney. Large granular lymphoma in nondomestic felids is likely rare since it has not been previously reported, but should be considered as a differential in any felid species with anterior uveitis or when lymphoma is considered. In the case of this caracal, the use of aqueous paracentesis with cytology was a powerful diagnostic.     

The pond network: can structural connectivity reflect on (amphibian) biodiversity patterns?

Landscape connectivity is a very recurrent theme in landscape ecology as it is considered pivotal for the long term conservation of any organism’s populations. Nevertheless, this complex concept is still surrounded by uncertainty and confusion, largely due to the separation between structural and functional connectivity. Amphibians are the most threatened vertebrates around the globe, in Europe mostly due to habitat alteration, and to their particular life cycle. Pond breeding amphibians are considered to be organised in metapopulations, enhancing the importance of landscape connectivity in this group of animals. We sampled the amphibian species present in two pond groups in Central Western Spain. We applied the graph theory framework to these two pond networks in order to determine the importance of each pond for the entire network connectivity. We related the pond importance for connectivity with the species richness present in each pond. We tested if connectivity (partially) determined the presence of the amphibian species sampled using logistic regression. The results show that the structural connectivity of the pond network impacts on the amphibian species richness pattern and that the importance of the pond for the connectivity of the network is an important factor for the presence of some species. Our results, hence, attest the importance of (structural) landscape connectivity determining the pattern of amphibian (functional) colonization in discrete ponds.     

Evaluation of bradyrhizobia strains isolated from field-grown soybean plants in Argentina as improved inoculants

Bradyrhizobium strains were isolated from nodules obtained from field-grown soybean plants sampled in 12 soybean production locations in Argentina. These fields had been annually cropped with soybean and did not show decreases in yields even though they had been neither N-fertilized nor inoculated for at least the last 5 years. We hypothesized that the isolated strains maintained high competitiveness and efficiency in fixing adequate N₂ levels. A set of strains that showed the highest nodular occupancy in each sampling location were assayed for symbiotic performance under greenhouse and field conditions and comparatively evaluated with Bradyrhizobium japonicum E109, the strain officially recommended for inoculant formulation in Argentina. An inoculant pool, formed by four strains obtained from nodules collected from Cañada Rica, developed higher nodular biomass than B. japonicum E 109 in assays carried out in greenhouses under well irrigated conditions. Additionally, neither nodule production nor specific nitrogenase activity decreased with respect to B. japonicum E 109 when plants were drought stressed during 7 days from sowing. The mean yields obtained under field conditions and plotted against the principal component one (CP1) obtained with an additive main effect and multiplicative interaction (AMMI) model showed that the inoculant pool from Cañada Rica had higher contribution to yield than strain E 109, although with lower environmental stability. The inoculant pool from Cañada Rica could be considered an improved inoculant and be used for preliminary assays, to formulate inoculants in Argentina.     

Flow cytometric analysis of peripheral blood mononuclear cells induced by experimental endotoxemia in horse

Cellular activation and functional cell surface markers were evaluated during experimentally-induced endotoxemia in healthy horses. Eight healthy adult horses were infused a low dose of endotoxin (lipopolysaccharide from Escherichia coli O26: B6, 30 ng/kg of body weight, IV) and five control horses were given an equivalent volume of sterile saline solution. Venous blood samples were collected for flow cytometric analysis of peripheral blood mononuclear cells (PBMCs) and to measure plasma endotoxin concentrations. Clinical signs of endotoxemia were recorded at 10, 20, 30, 40, 50 min, 1, 2, 3, 4, 8, 16, 24 and 48 hr after endotoxin or saline solution administration. Clinical findings characteristic of endotoxemia (tachycardia, tachypnea, increased rectal temperature, and leukopenia) occurred transiently in all horses administered endotoxin; however, plasma endotoxin concentrations were detectable in only 50% (4/8) of the endotoxin-infused horses. The percentage of CD4(+), CD5(+), and CD8(+) cells decreased while the percentage of CD14(+), IgM(+), and MHC class II(+) cells increased significantly after endotoxin infusion. Alterations in the immunophenotype of PBMCs from horses with experimentally-induced endotoxemia were associated with changes in vital signs, indicating that endotoxin altered the immuno balance.     

Pharmacokinetics of azithromycin in the blue and gold macaw (Ara ararauna) after intravenous and oral administration.

Azithromycin is classified as an azalide, a subclass of macrolide antimicrobials with a broad spectrum of activity in vitro against many potential bacterial pathogens including spirochetes, anaerobes, and Chlamydia trachomatis. Because of limited data on the use of azithromycin in avian medicine, this study was designed to determine the pharmacokinetics of azithromycin in blue and gold macaws (Ara ararauna), a species commonly seen in clinical practice. Azithromycin (10 mg/kg) was administered via crop lavage to five birds and intravenously to five birds, and blood samples were obtained at 0, 0.5, 1, 3, 6, 12, 24, 48, 72, and 96 hr post-azithromycin administration. Following a 4-wk washout period, the study was repeated with a complete crossover study performed. Concentration of azithromycin in plasma samples was quantified using a validated liquid chromatography/mass spectrometry assay. Pharmacokinetic parameters were determined using noncompartmental analysis. Based on the pharmacokinetic data generated from this study, a starting dose of azithromycin at 10 mg/kg p.o. every 48 hr for susceptible bacterial infections in blue and gold macaws is recommended.     

Mycobacterium asiaticum infection in a red-handed tamarin (Saguinus midas).

A 4-yr-old, intact male red-handed tamarin (Saguinus midas) was evaluated because of a 6-mo history of an enlarging axillary mass. Diagnostic findings included a positive intradermal tuberculin test, persistent severe leukocytosis, and hyperglobulinemia. A nontuberculous mycobacterium species isolated from the mass was identified as Mycobacterium asiaticum using 16s ribosomal DNA sequencing and high-performance liquid chromatography.     

Host-parasite relationships of Zootoca vivipara (Sauria: Lacertidae) in the Pyrenees (North Spain)

The helminths infesting the common lizard, Zootoca vivipara (Jacquin, 1787), were studied with special attention to the relations between the number of nematodes, Oswaldocruzia filiformis (Goeze, 1782), and the size, sex and age class of the host. The possible seasonality of the parasite intensity and the relationship with the feeding habits of the host were also tested. Helminth infracommunities of Z. vivipara were depauperate with lizards harbouring only two species, the trematode Plagiorchis molini (Lent et Freitas, 1940) and the nematode O. filiformis. A positive correlation between host size and the number of O. filiformis was found for female Z. vivipara. However, no correlation was detected between intensity and sex or age class. The feeding habits of Z. vivipara, the isolation of the population studied and the low level of interaction with other reptilian or amphibian species are suggested as the causes of the depauperate helminth infracommunities found in this lacertid lizard.     

Effects of hypercalcemia on serum concentrations of magnesium, potassium, and phosphate and urinary excretion of electrolytes in horses

OBJECTIVE: To determine effects of experimentally induced hypercalcemia on serum concentrations and urinary excretion of electrolytes, especially ionized magnesium (iMg), in healthy horses. ANIMALS: 21 clinically normal mares. PROCEDURES: Horses were assigned to 5 experimental protocols (1, hypercalcemia induced with calcium gluconate; 2, hypercalcemia induced with calcium chloride; 3, infusion with dextrose solution; 4, infusion with sodium gluconate; and 5, infusion with saline [0.9% NaCl] solution). Hypercalcemia was induced for 2 hours. Dextrose, sodium gluconate, and saline solution were infused for 2 hours. Blood samples were collected to measure serum concentrations of electrolytes, creatinine, parathyroid hormone, and insulin. Urine samples were collected to determine the fractional excretion of ionized calcium (iCa), iMg, sodium, phosphate, potassium, and chloride. RESULTS: Hypercalcemia induced by administration of calcium gluconate or calcium chloride decreased serum iMg, potassium, and parathyroid hormone concentrations; increased phosphate concentration; and had no effect on sodium, chloride, and insulin concentrations. Hypercalcemia increased urinary excretion of iCa, iMg, sodium, phosphate, potassium, and chloride; increased urine output; and decreased urine osmolality and specific gravity. Dextrose administration increased serum insulin; decreased iMg, potassium, and phosphate concentrations; and decreased urinary excretion of iMg. Sodium gluconate increased the excretion of iCa, sodium, and potassium. CONCLUSIONS AND CLINICAL RELEVANCE: Hypercalcemia resulted in hypomagnesemia, hypokalemia, and hyperphosphatemia; increased urinary excretion of calcium, magnesium, potassium, sodium, phosphate, and chloride; and induced diuresis. This study has clinical implications because hypercalcemia and excessive administration of calcium have the potential to increase urinary excretion of electrolytes, especially iMg, and induce volume depletion.     

A new system to reduce formaldehyde levels improves safety conditions during gross veterinary anatomy learning

Dissection is a very useful method of learning veterinary anatomy. However, formaldehyde, which is widely used to preserve cadavers, is an irritant, and it has recently been classified as a carcinogen. In 1997, the Instituto Nacional de Seguridad e Higiene en el Trabajo [National Institute of Workplace Security and Hygiene] found that the levels of formaldehyde in our dissection room were above the threshold limit values. Unfortunately, no optimal substitute for formaldehyde is currently available. Therefore, we designed a new ventilation system that combines slow propulsion of fresh air from above the dissection table and rapid aspiration of polluted air from the perimeter. Formaldehyde measurements performed in 2004, after the introduction of this new system into our dissection laboratory, showed a dramatic reduction (about tenfold, or 0.03 ppm). A suitable propelling/aspirating air system successfully reduces the concentration of formaldehyde in the dissection room, significantly improving safety conditions for students, instructors, and technical staff during gross anatomy learning.