Real-time PCR investigation of feline leukemia virus proviral and viral RNA loads in leukocyte subsets

Cats exposed to feline leukemia virus (FeLV), a naturally occurring gammaretrovirus develop either progressive or regressive infection. Recent studies using analyses with enhanced sensitivity have correlated loads throughout FeLV with the clinical outcome, though remarkably, during the acute phase of infection, proviral and viral RNA burdens in the peripheral blood do not differ between groups. We hypothesized that viral loads in specific leukocyte subsets influence the infection outcome. Using a method established to determine the proviral and cell-associated viral RNA loads in specific leukocyte subsets, we evaluated viral loads in eleven FeLV-exposed specific pathogen-free (SPF) cats 2.5 years post-infection. Six cats had undergone regressive infection whereas five were persistently viremic. Aviremic cats had lower total proviral blood loads than the persistently infected cats and FeLV proviral DNA was shown to be integrated into genomic DNA in four out of four animals. Lymphocytes were predominantly infected vs. moncytes and granulocytes in aviremic cats. In contrast, persistently viremic cats were provirus-positive in all leukocyte subsets. The acute phase kinetics of FeLV infection were analyzed in two additional cats; an early lymphoreticular phase with productive infection in lymphocytes in both cats and in monocytes in one cat was followed by infection of the granulocytes; both cats became persistently infected. These results indicate that FeLV persistent viremia is associated with secondary viremia of bone marrow origin, whereas regressive cats only sustain a non-productive infection in low numbers of lymphocytes.     

Frequencies of feline blood types in the Rio de Janeiro area of Brazil

Background: The distribution and frequency of blood types in cat populations vary according to geographic region and breed. Frequencies of feline blood types in Rio de Janeiro city, as well as in other Brazilian areas, are unknown, and the risk of unmatched transfusions and neonatal isoerythrolysis has not been estimated. Objectives: The purpose of this study was to determine the frequency of feline blood types in the area of Rio de Janeiro, Brazil. Methods: EDTA blood samples were obtained from 172 nonpedigreed domestic shorthair (DSH) cats (92 female, 80 male, 3 months-20 years old) in different sites of Rio de Janeiro city. Blood typing was performed by agglutination assays using Triticum vulgaris lectin and feline anti-A serum. The hemagglutination results for type B and AB cats were confirmed by high-performance thin-layer chromatography (HPTLC) of erythrocyte membrane gangliosides. Results: The majority (163/172, 94.8%) of cats were type A, 2.9% were type B, and 2.3% were type AB. High-titer anti-A serum agglutinated RBCs from all cats in type A and type AB blood groups, with 3+ to 4+ agglutination. The probability that a type A cat would receive type B or AB blood in a first random transfusion was calculated as 2.25% and 2.20%, respectively. HPTLC analysis of glycolipids yielded a chromatographic profile characteristic of feline gangliosides for all blood groups. Conclusions: These results indicate a high prevalence of type A cats in Rio de Janeiro, Brazil, and a low frequency of type B and AB cats, consistent with what has been observed for DSH cats in other regions of the world.     

Relative insensitivity of avian skeletal muscle glycogen to nutritive status

Previous studies in avian species have reported time-dependent losses in muscle glycogen with prolonged feed withdrawal (FW). However, cervical dislocation was used to collect tissues, a method that results in significant involuntary muscle convulsions. In this study, cervical dislocation alone was found to reduce muscle glycogen by 23%, therefore, barbiturate overdose was used to collect tissue samples before and after FW, at the end of refeeding, and from continuously fed controls at each interval. Additionally, plasma samples from 6-wk-old male chickens were taken at the initiation and end of a 24-hr feed withdrawal, and at various times during refeeding. After 24 hr of FW, liver glycogen decreased markedly (77%; P < 0.05), whereas muscle glycogen decreased slightly and transiently, such that it returned to and remained at control levels, even after prolonged (72 hr) FW. Plasma glucose was decreased, whereas glucagon was elevated after a 24-hr feed withdrawal (P < 0.05), when compared with control concentrations. Muscle glycogen levels were not significantly increased over control levels after refeeding, but liver glycogen was increased by 380% (P < 0.05). Feed deprivation followed by refeeding resulted in increased circulating insulin and glucose levels when compared with control levels. Therefore, by using methods of tissue collection that ensure that muscle glycogen determinations are not confounded by artifactual degradation, these results verify that regulation of avian muscle glycogen stores is similar to that in mammals.     

Policy analysis of the ‘MPA‐process’ in temperate continental shelf areas

• 1. The decision to designate, implement and manage marine protected areas (MPAs) is often made ad hoc without clear guiding procedures. This study evaluates the process of establishment and management of MPAs in temperate soft‐bottom marine areas, including identification of objectives, site selection, designation, implementation, ecological effectiveness and socio‐economic impacts.
• 2. For the first time, literature about marine conservation strategies in soft‐bottom temperate areas is brought together in one ‘systems approach’, which is visualized in a flow chart including three phases: setting policy objectives, making decisions and evaluating the eventual effects of the MPA. Policy objectives are generally easy to identify and in most cases national policy objectives are driven by international and regional legal obligations. The decision making process is the most complex phase, as the acceptance of MPAs has to be balanced against the human activities that take place in the area.
• 3. The relation between fisheries and MPA‐management appears to be most challenging in soft‐bottom temperate marine areas because of conflicting interests and institutional differences. Activities limited in space and not relying directly on ecosystem functions (e.g. offshore energy production and aggregate extraction) are generally easier to manage than fisheries.
• 4. The conceptual mapping exercise presented here serves as a basis for a systems approach for MPAs and has been tested for the Belgian coastal environment. In the Belgian ‘MPA‐process’, the application of the systems approach proves to be useful in providing insight into the complex interactions of various authorities with scattered jurisdictions.
• 5. The unified and simplified representation of the various aspects is (1) a useful communication tool for policy makers and managers to inform other sectors and the public at large and (2) a valuable support during the ‘MPA‐process’ that considerably enhances the prospects for success.

Copyright © 2008 John Wiley & Sons, Ltd.     

Design,optimization, and application of a conventional PCR assay with an internal control for detection of ‘Candidatus Mycoplasma turicensis’ 16S rDNA in domestic cats from Brazil

Background: ‘Candidatus Mycoplasma turicensis’ (CMtc) is a hemotrophic bacterial species that can, alone or in combination, induce anemia in cats. The diagnostic test of choice for hemoplasma infections is PCR. Conventional PCR assays have been developed for the detection of Mycoplasma haemofelis (Mhf) and ‘Candidatus M. haemominutum’ (CMhm) but not for CMtc. Although real‐time PCR assays have been reported for all of the feline hemoplasmas, the expense of necessary instrumentation precludes its use in Brazil and many other countries. Objectives: The goals of this study were to develop and optimize a conventional PCR assay to diagnose CMtc using an internal control to detect false‐negative results, and to evaluate the occurrence of CMtc infection in domestic cats from Brazil. Methods: Species‐specific primers were designed and a PCR assay was developed for the detection of CMtc 16S rDNA in cat blood. Sensitivity was determined by serial 10‐fold dilutions of plasmid and DNA extracted from blood from an experimentally infected cat. EDTA blood samples from 373 cats were collected. DNA was extracted using a silica‐based protocol and tested using the PCR assay. Results: Primer concentration, annealing temperature, and MgCl₂ concentration were optimized in the presence and absence of the internal control. Two samples negative for the internal control were excluded. Of the remaining 371 samples (117 healthy and 254 unhealthy cats), 17 (4.6%) were positive for CMtc. Conclusion: These results demonstrate the utility of an optimized PCR assay to detect CMtc in feline blood samples. We also report for the first time the prevalence of CMtc infection in domestic cats in Brazil.     

Distribution of equine infectious anemia in horses in the north of Minas Gerais State, Brazil.

The paper examines the prevalence of equine infectious anemia (EIA) in horse populations in the northern part (comprising 89 cities) of Minas Gerais State, Brazil, from January 2002 to December 2004. Data on 8,981 agar gel immunodiffusion test results from the region were used as input for a statistical and autoregressive analysis model to construct a city-level map of the distribution of EIA prevalence. The following EIA prevalence (P) levels were found: 49 cities with 0 < P < or = 0.5%, 26 with 0.5% < P < or = 1.5%, 10 with 1.5% < P < or = 5%, and 4 with 5% < P < or = 25%.     

Seasonal influence on hematologic values and hemoglobin electrophoresis in Brazilian boa constrictor amarali.

As ectothermic animals, snakes depend exclusively on the environment for proper temperature maintenance, which may greatly influence their activity. Twenty-five adult Boa constrictor amarali snakes maintained in captivity were used to determine the influence of seasons on their hematologic values and electrophoretic profile of hemoglobin. A complete blood cell count (CBC) and examination for hemoparasites were performed in the summer and winter of 2004. Hemoglobin was stored for later electrophoresis. Significant differences (P < 0.05) were obtained in RBC, WBC, lymphocyte, thrombocyte, and monocyte counts, demonstrating the importance of the period of the year in the interpretation of reference values in these animals. Two snakes were detected with blood parasites (Hepatozoon sp.) in the winter and four in the summer, although it appears that their presence did not cause any significant alterations in the CBC. The electrophoretic analysis of the samples demonstrated two-four hemoglobin bands in this species.     

Enhancement of attraction and trap catches of the old-house borer, Hylotrupes bajulus (Coleoptera: Cerambycidae), by combination of male sex pheromone and monoterpenes

Monoterpenoid compounds extracted from wood of Scots pine, Pinus sylvestris L, synergized the attraction of the old-house borer, Hylotrupes bajulus (L), to the male pheromone (3R)-3-hydroxy-2-hexanone ((3R)-ketol) + 1-butanol. Glasshouse experiments using ground traps baited with extracts derived from Scots pine wood or the monoterpenes (+)-alpha-pinene, (-)-verbenone, (-)-trans-pinocarveol and (+)-terpinen-4-ol attracted significantly more H bajulus females, but caught fewer of them, than the synthetic pheromone mixture alone. Traps baited with higher concentrations of the monoterpene mixture attracted fewer females than those baited with lower dosages, whilst very high concentrations of the mixture (6-10 vials) caught no insects. However, a combination of (3R)-ketol + 1-butanol or (+/-)-3-ketol + 1-butanol with monoterpenes resulted in the capture of significantly more females than either the sex pheromone or the monoterpene mixture alone. Traps baited with a blend of the male's sex pheromone or the monoterpenes attracted significantly more, but caught fewer, males than females. Here again, a combination of the above blends enhanced the attraction of males significantly when compared with the attractancy of either of the compounds/mixtures used alone.