Diagnosis of systemic cryptococcosis by fecal cytology in a dog

A 3-year-old Boxer was presented with progressive diarrhea, vomiting, and lethargy of 5-months duration. The dog had watery black feces, a mature neutrophilia, and microcytic anemia. Cytologic evaluation of a direct fecal smear stained with Wright's-Giemsa revealed numerous encapsulated, narrow-based, budding organisms consistent with Cryptococcus sp. Pyogranulomatous inflammation and Cryptococcus organisms also were observed in ultrasound-guided fine-needle aspirates of the small intestine and mesenteric lymph nodes, and in histologic sections of colonic biopsies obtained by endoscopy. Multifocal chorioretinitis by fundic examination was consistent with systemic mycosis, and the reciprocal antigen titer (1600) on a cryptococcal antigen latex agglutination test for Cryptococcus neoformans was markedly increased. Using immunohistochemistry, the organism was identified further as C neoformans var. grubii (C neoformans var. neoformans serotype A). After 3 weeks of antifungal treatment, ultrasound examination revealed urinary bladder wall thickening, and Cryptococcus organisms were found in a urine sediment preparation. After 4 months of treatment, the dog was clinically normal and had no abnormal findings on CBC, serum biochemistry, urinalysis, or fecal cytology; however, the antigen titer remained unchanged, mesenteric lymphadenomegaly and jejunal wall thickening were still evident, and cytologic evaluation of fine-needles aspirates of the jejunal wall revealed budding Cryptococcus organisms. Intestinal involvement in dogs with cryptococcosis is rare, and diagnosis by fecal cytology has not been documented previously.     

Oxytocin Secretion and Management of Parturition in the Pig

This paper will examine the augmentation of oxytocin (OT) secretion in the final day before parturition in the pig, and review the key endocrine systems of influence. Recent experiments have shown that increases in plasma OT above baseline secretion were not seen until 7 hours prior to the birth of the first piglet. Progesterone release begins to decline some days before birth and is unlikely to provide such acute control of OT release immediately before birth. The involvement of relaxin is complex but it is possible that the prepartum relaxin surge, which ends close to the OT rise, attenuates OT secretion to prevent excessive myometrial activity until cervical softening has occurred. Increasing myometrial electromyographic activity appears to be seen as relaxin concentrations decline and OT increase. Endogenous opioid peptides within the hypothalamus exert a profound influence upon OT secretion during birth, and some effects are also seen prepartum. It has been proposed that this system may allow parturition to be interrupted or slowed in response to changes in environment. The therapeutic choice of exogenous injections of OT to control the onset time of parturition will be discussed in the light of current physiological knowledge.     

Landscape dynamics of floral resources affect the supply of a biodiversity-dependent cultural ecosystem service

Context

Cultural ecosystem services, many of which depend on biodiversity, are recognized as important but seldom quantified biophysically across landscapes. Furthermore, many ecosystem service models are static, and the supply of cultural ecosystem services may be misrepresented if seasonal shifts in biotic communities are ignored.

Objectives

We modeled landscape dynamics of wildflower blooms in a temperate montane landscape to determine (1) how floral resources (wildflower species richness, abundance, timing, and presence of charismatic species) changed over the growing season, (2) how projected wildflower viewing hotspots varied over space and time, and (3) how spatial shifts in floral resources affected potential public access to wildflower viewing.

Methods

Data were collected at 63 sites across a rural-to-urban gradient in the Southern Appalachian Mountains (USA). Generalized linear models were used to identify factors affecting floral resources at two temporal scales. Floral resources were projected across the landscape and hotspots of wildflower viewing were quantified using overlay analysis.

Results

Floral resources were affected by topoedaphic conditions, climate, and surrounding building density and changed seasonally. Seasonal models revealed locational shifts in ecosystem service hotspots, which changed the proportion of hotspots accessible to the public and identified wildflower-viewing opportunities unnoticed by static models.

Conclusion

Relationships between landscape gradients, biodiversity, and ecosystem service supply varied seasonally, and our models identified cultural ecosystem service hotspots otherwise obscured by simple proxies. Landscape models of biodiversity-based cultural ecosystem services should include seasonal dynamics of biotic communities to avoid under- or over-emphasizing the importance of particular locations in ecosystem service assessments.

     

Evaluation of Two Reagent Strips and Three Reflectance Meters For Rapid Determination of Blood Glucose Concentrations

We evaluated three reflectance meters (Accu-Chek II, Glucometer II, and Glucoscan 2000) and two reagent strips (Chemstrip bG and Glucostix) for accuracy and precision in determining blood glucose concentrations in the dog. To evaluate accuracy, we compared results of blood glucose determinations performed on 95 samples using the various strips and meters vs. the glucose concentrations obtained using the glucose-oxidase method on a Beckman Glucose Analyzer. Accuracy was evaluated statistically using least squares regression analysis. To evaluate precision, samples in various ranges of blood glucose concentration were tested repeatedly (20 times within a 1-hour period) on the same reflectance meter. Coefficient of variation (CV) was determined to evaluate reproducibility of results. Overall, there were significant correlations (P less than 0.001) between the laboratory glucose values and the blood glucose concentrations obtained with Chemstrip bG (r = 0.976), Glucostix (r = 0.904), Accu-Chek II (r = 0.986), Glucometer II (r = 0.911) and Glucoscan 2000 (r = 0.944). In the precision study, all three meters had excellent CVs in the normal range (3.6% to 4.9%). However, Accu-Chek II was found to be more precise in the hypoglycemic and hyperglycemic ranges (3.6% and 2.6%, respectively) than either Glucometer II (8.8% and 5.4%) or Glucoscan 2000 (7.8% and 8.2%). The results of this study indicate that all of the meters and reagent strips tested are highly accurate in determining blood glucose concentrations in the dog. However, both in terms of accuracy and reproducibility of results, Accu-Chek II and Chemstrip bG, gave the highest correlation coefficients and, as such, are probably of the greatest clinical value.     

Enzyme-linked immunosorbent assays for detecting antibody to Rickettsia australis in sera of various animal species

New endemic areas of spotted fever-like rickettsial disease have been found in south-eastern Australia (Gippsland, Victoria and Flinders Island, Tasmania). The rickettsia responsible is currently unknown although it may be Rickettsia australis. To investigate serological evidence of rickettsial exposure in various wild animal species, a competitive ELISA was developed which detected antibodies to R. australis. It was based on inhibition of an indirect ELISA detecting antibody to R. australis in guinea pig sera. Pre- and post-infection sera from 2 dogs, 2 rabbits, 5 mice and 6 rats, experimentally infected with R. australis, were tested by competitive ELISA. The results showed that all pre-infection sera were negative and all post-infection sera positive for antibody to R. australis. To test the utility of the competitive ELISA for detecting natural rickettsial infection in non-laboratory animals, 51 dog sera, negative for rickettsial antibody by immunofluorescence (IF) and 20 IF positive dog sera (collected from various locations on the east coast of Australia) were tested. Compared to the IF test the competitive ELISA was 90% sensitive and 96% specific. This new test has potential for detecting antibody to R. australis in the sera of different wild animal species.