Prevalence of Hantaviruses Harbored by Murid Rodents in Northwestern Ukraine and Discovery of a Novel Puumala Virus Strain.

In Europe, two species of hantaviruses, Puumala orthohantavirus (PUUV) and Dobrava orthohantavirus (DOBV), cause hemorrhagic fever with renal syndrome in humans. The rodent reservoirs for these viruses are common throughout Ukraine, and hence, the goal of this study was to identify the species and strains of hantaviruses circulating in this region. We conducted surveillance of small rodent populations in a rural region in northwestern Ukraine approximately 30 km from Poland. From the 424 small mammals captured, we identified nine species, of which the most abundant were Myodes glareolus, the bank vole (45%); Apodemus flavicollis, the yellow-necked mouse (29%); and Apodemus agrarius, the striped field mouse (14.6%) Using an indirect immunofluorescence assay, 15.7%, 20.5%, and 33.9% of the sera from M. glareolus, A. glareolus, and A. flavicollis were positive for hantaviral antibodies, respectively. Additionally, we detected antibodies to the hantaviral antigen in one Microtus arvalis, one Mus musculus, and one Sorex minutus. We screened the lung tissue for hantaviral RNA using next-generation sequencing and identified PUUV sequences in 25 small mammals, including 23 M. glareolus, 1 M. musculus, and 1 A. flavicollis, but we were unable to detect DOBV sequences in any of our A. agrarius specimens. The percent identity matrix and Bayesian phylogenetic analyses of the S-segment of PUUV from 14 M. glareolus lungs suggest the highest similarity (92-95% nucleotide or 99-100% amino acid) with the Latvian lineage. This new genetic information will contribute to future molecular surveillance of human cases in Ukraine.

Free-living capybaras (Hydrochoerus hydrochaeris) in an urban area in Brazil: biochemical and hematological parameters

Capybaras have found favorable conditions for survival and reproduction in green urban environments. In recent years, the population of these large rodents has been increasingly abundant in several brazilian cities such as Uberlândia, a municipality of the southeastern region with a Cerrado biome. Capybaras are important in the Brazilian Spotted Fever epidemiological chain, by amplifying infection rates of the vector population. However, knowledge of this host's physiology is scarce. Thus, the aim of this work was to describe hematological and biochemical parameters of free-living capybaras groups in urbanized areas in the city of Uberlândia, Minas Gerais State, Brazil. Capybaras were captured in 4 different locations of Uberlândia city, Minas Gerais state, including 1 Condominium (P1), 1 Private Market Garden (P2), 1 Private Club (P3) and 1 Municipal Park (P4). The animals were baited into an octagonal iron corral and chemically contained with anesthetic darts. After sedated, blood was collected from the femoral vein in tubes with and without EDTA. Biochemical evaluation, hematological analysis with differential leukocyte counts and search for Dirofilaria sp. were done. The blood count and biochemistry values obtained from animals of different ages, sex and sectors (P1, P2, P3 and P4) were submitted to the Shapiro-Wilk normality test, considering 95% significance. Values that had a normal distribution were subjected to ANOVA tests followed by Student's t-test. Values that did not follow normality were submitted to the Kruskal-Wallis test, to obtain a P-value, with a significance level of 95%. A total of 19 capybaras were captured: 4 in P1, 6 in P2, 4 in P3 and 5 in P4. From the 19 animals, 13 were females (68.42%) and 6 were males (31.57%), 12 adults (63.15%) and 7 juveniles (36.84%). Apart from occasional skin scars and moderate to intense Ambyomma spp. tick infestations, all captured animals were healthy on a broad examination. From 5 animals captured in P4, despite the use of anticoagulant, blood from 4 animals clotted fast. No microfilariae were found in the thick drop test in any of the 19 animals sampled, and in 2 adult female capybaras captured in P1, Kurloff cells were observed. Hematological and biochemical values presented no major differences when comparing sex and age. Nevertheless, differences in liver and kidney profile were observed between the capybara groups, including ALT, alkaline phosphorus, BUN and creatinine. Blood from 4 animals clotted fast, despite the use of EDTA tubes. Blood clotting of samples with anticoagulant in this work could be associated with some physiological features inherent to capybaras. Many attempts were required to obtain enough blood from each individual due to the rapid hemostasis, what come in accordance with reports in literature. Kurloff cells were observed in 2 adult female capybaras captured in P1, which can be found in peripheral blood of female rodents during follicular phase of estrous cycle. Hematological and biochemical values differences in liver enzymes such as ALT and alkaline phosphorus, and kidney profile enzymes including BUN and creatinine could be associated to capture stress or dietetic variation between groups. Despite statistical relevant, the values were still in accordance with other works, although comparisons should be done with caution since various environments exert a diverse array of stimulus upon the animals such as parasitic, infective, stress, nutritional, social and undoubtedly blood parameters mirror them. In conclusion, this work contributes to the standardization of free-living capybaras' physiological parameters in urban areas.(AU)

Perfil hematológico e bioquímico sérico de capivaras (Hydrochoerus hydrochaeris) de vida livre nos biomas Mata Atlântica e Caatinga / Hematological and serum biochemical profile of free-living capybaras (Hydrochoerus hydrochaeris) in Atlantic Forest and Caatinga biomes

Devido à ausência de estudos sobre capivaras na região Nordeste do Brasil, o objetivo deste estudo foi avaliar a sanidade desses roedores de vida livre em três áreas dos biomas Mata Atlântica (2) e Caatinga (1) do estado de Pernambuco, por meio da determinação de parâmetros da hematologia e bioquímica sérica. De novembro de 2016 a dezembro de 2017, foram capturados 21 animais, dos quais foram coletadas amostras de sangue para avaliação hematológica (eritrograma, leucograma e plaquetometria) e bioquímica sérica (atividade enzimática, perfil proteico, energético e mineral). A maioria dos parâmetros esteve dentro dos valores de normalidade para a espécie, embora alguns apresentassem diferenças estatisticamente significativas de acordo com a área de estudo (hemoglobina, hematócrito, VCM, CHCM, eosinófilos, fosfatase alcalina, proteína total, albumina, ácido úrico, creatinina, lactato, sódio e magnésio) e o sexo dos animais (ácido úrico). Os parâmetros obtidos são apresentados como referência e atestam a sanidade e o bom estado nutricional de populações de capivaras nos biomas Mata Atlântica e Caatinga da região Nordeste do Brasil. As informações aportadas neste estudo pioneiro na região Nordeste contribuem para aumentar o conhecimento sobre a ecofisiologia e a conservação in situ de capivaras.(AU)

Due to the lack of studies about capybaras in the northeast region of Brazil, the objective of this study was to evaluate the health status of free-ranging capybaras in three areas of Atlantic Forest (2) and Caatinga (1) biomes in Pernambuco state, through the determination of hematological and serum biochemical parameters. From November 2016 to December 2017, 21 animals were captured and blood samples were collected for the hematological (erythrogram, leukogram and platelet counts) and serum biochemistry (enzymatic activity, protein, energy and mineral profile) evaluation. Hematological and serum biochemical parameters were within the normal range for the species, but some presented statistically significant variations according to the study area (hemoglobin, hematocrit, MCV, MCHC, eosinophils count, alkaline phosphatase, total proteins, albumin, uric acid, creatinine, lactate, sodium and magnesium) and sex of the animals (uric acid). The parameters obtained are presented as reference and attest to the health and good nutritional status of populations of capybaras in the Atlantic Forest and Caatinga biomes of northeastern Brazil. The information provided in this pioneering study in the northeast region contributes to increased knowledge about the ecophysiology and in situ conservation of capybaras.(AU)

Elevated basal corticosterone levels increase disappearance risk of light but not heavy individuals in a long-term monitored rodent population.

According to the cort-fitness hypothesis, glucocorticoid levels correlate negatively with fitness. However, field studies found mixed support for this hypothesis, potentially because the association between glucocorticoids and fitness might depend on prevailing environmental conditions. Based on the long-term monitoring of a natural rodent population, we tested whether individuals with elevated corticosterone levels were more likely to disappear, accounting for individual condition and among-year variation in food availability, population density and predation pressure. We used basal corticosterone levels measured at the onset of the pre-breeding season in 331 African striped mice from six generations. While basal corticosterone levels were highly repeatable within individuals, between-individual variation was large. Survival analysis revealed that disappearance risk over the pre-breeding season increased with elevated basal corticosterone levels for light but not for heavy individuals. High levels of corticosterone may be more deleterious to smaller individuals (i.e. through allostatic overload), eventually increasing their mortality risk, and disappearance would represent actual death. An alternative non-exclusive explanation could be that high levels of corticosterone selectively trigger dispersal in light individuals, and disappearance would rather reflect their departure from the population. Although environmental conditions varied considerably among generations, none of the interactions between corticosterone and environmental variables were significant. Disappearance probability was positively correlated with both predation pressure and with food availability, a factor favoring dispersal. In sum, elevated basal corticosterone levels increased disappearance in light striped mice, either directly via reduced survival prospects and/or indirectly via dispersal.

Detection of New World Hantavirus Antibodies in Rodents of Eastern New Mexico, USA.

Hantaviruses, causal agents of the potentially lethal hantavirus pulmonary syndrome, have widely distributed rodent hosts. Using an enzyme-linked immunosorbent assay, we tested blood from 398 wild rodents captured in eastern New Mexico, US in 2015-17 and found 42 antibody-positive samples representing six genera.

A Tale of Two Valleys: Disparity in Sin Nombre Virus Antibody Reactivity Between Neighboring Mojave Desert Communities.

INTRODUCTION: Hantaviruses are a group of globally distributed rodent-associated viruses, some of which are responsible for human morbidity and mortality. Sin Nombre orthohantavirus, a particularly virulent species of hantavirus associated with Peromyscus spp. mice, is actively monitored by the Department of Public Health in California (CDPH). Recently, CDPH documented high (40%) seroprevalence in a potentially novel reservoir species, the cactus mouse (Peromyscus eremicus) in Death Valley National Park. METHODS: This study was performed in the extremely isolated Mojave Desert Amargosa River valley region of southeastern Inyo County, California, 105 km from Death Valley, approximately over the same time interval as the CDPH work in Death Valley (between 2011 and 2016). Similar rodent species were captured as in Death Valley and were tested for select hantaviruses using serology and RT-PCR to assess risk to human health and the conservation of the endemic endangered Amargosa vole. RESULTS: Among 192 rodents tested, including 56 Peromyscus spp., only one seropositive harvest mouse (Reithrodontomys megalotis) was detected. DISCUSSION: These data highlight the heterogeneity in the prevalence of hantavirus infection even among nearby desert communities and suggest that further studies of hantavirus persistence in desert environments are needed to more accurately inform the risks to public health and wildlife conservation.

Biochemical and histological characterisation of an experimental rodent model of non-alcoholic steatohepatitis - Effects of a peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist and a glucagon-like peptide-1 analogue.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a prevalent disease that is highly associated with the metabolic syndrome and type II diabetes. The development of in vivo models that reflect all nuances of the human NASH pathology is essential for drug discovery and development. We aimed to further characterise a dietary induced model of NASH both biochemically and histologically. In addition, we also investigated whether pioglitazone and liraglutide, drugs that have both been investigated as potential NASH treatments, could modulate the pathological changes induced by the NASH diet. Furthermore, to aid the translation of data from pre-clinical in vivo models, we aimed to adapt the NASH Clinical Research Network (CRN) histological score system for use in rodent studies. METHODS: Sprague Dawley rats were fed a high-fat diet (HFD) for 9 weeks, after which they were switched to a high fat, high cholesterol and cholate diet (HFCC) for 12 weeks. The rats were divided into treatment groups, receiving either 30 mg/kg pioglitazone p.o. SID or liraglutide s.c. 200 µg/kg BID or the respective vehicles. Serum levels of triglycerides (TG), cholesterol (Chol), LDL, HDL, AST and ALT, as well as body weight were assessed in all subjects. Upon termination, the liver was weighed and evaluated histologically using modified NASH-CRN criteria. RESULTS: HFCC feeding induced severe hepatic injury and hepatomegaly as indicated by significant increases in AST, ALT and an increased liver weight. Additionally, HFCC feeding induced dyslipidaemia, significant increases in circulating cholesterol and LDL were observed. No obesogenic effect of the HFCC diet was observed, though the diet did induce insulin resistance. Histological analysis showed that the HFCC diet induced several NASH like features, though it did not induce the development of severe fibrosis. However, microgranulomas were often prevalent in addition to lobular inflammatory foci. Pioglitazone showed little efficacy upon both biochemical and histological features. However, liraglutide induced weight loss, improved glycaemic control, reduced ALT and AST and showed some beneficial effects upon steatosis and lobular inflammation. CONCLUSION: Similar to previous reports we have shown that the atherogenic diet, HFCC, induces a phenotype akin to that seen in human NASH patients. Despite inducing all histological features of NASH, HFCC feeding does not promote the development of significant fibrosis within rodents. Pioglitazone and liraglutide have been investigated as potential NASH treatments. Within this model of NASH we have shown that pioglitazone has little efficacy, whereas liraglutide reduced the levels of circulating aminotransferases and had some beneficial effects upon NASH histological parameters.

Potential effects of blood meal host on bacterial community composition in Ixodes scapularis nymphs.

Tick microbiomes may play an important role in pathogen transmission. However, the drivers of microbiome variation are poorly understood, and this limitation has impeded mechanistic understanding of the functions of microbial communities for pathogen acquisition. The goal of this research was to characterize the role of the blood meal host in structuring the microbiome of Ixodes scapularis, the primary vector of Lyme disease in the eastern United States, and to determine if ticks that fed from different host species harbor distinct bacterial communities. We performed high-throughput 16S rDNA amplicon sequencing on I. scapularis nymphs that fed as larvae from known wildlife hosts: raccoon, Virginia opossum, striped skunk, red squirrel or gray squirrel. Using Analysis of Similarity, we found significant differences in the abundance-weighted Unifrac distance matrix among ticks fed from different host species (p = 0.048) and a highly significant difference in the weighted and unweighted Unifrac matrices for individuals within species (p < 0.01). This finding of associations between the blood meal host and I. scapularis microbiome demonstrates that the blood meal host may be a driver of microbiome variation that should be accounted for in studies of pathogen acquisition by ticks.

Different regulation of cortisol and corticosterone in the subterranean rodent Ctenomys talarum: Responses to dexamethasone, angiotensin II, potassium, and diet.

When harmful environmental stimuli occur, glucocorticoids (GCs), cortisol and corticosterone are currently used to evaluate stress status in vertebrates, since their secretions are primarily associated to an increased activity of the hypothalamic-pituitaryadrenal (HPA) axis. To advance in our comprehension about GCs regulation, we evaluated the subterranean rodent Ctenomys talarum to assess cortisol and corticosterone response to (1) the negative feedback of the HPA axis using the dexamethasone (DEX) suppression test, (2) angiotensin II (Ang II), (3) potassium (K+) intake, and (4) different diets (vegetables, grasses, acute fasting). Concomitantly, several indicators of individual condition (body mass, neutrophil to lymphocyte ratio, blood glucose, triglycerides and hematocrit) were measured for diet treatments. Results confirm the effect of DEX on cortisol and corticosterone in recently captured animals in the field but not on corticosterone in captive animals. Data suggest that Ang II is capable of stimulating corticosterone, but not cortisol, secretion. Neither cortisol nor corticosterone were responsive to K+ intake. Cortisol levels increased in animals fed with grasses in comparison to those fed with vegetables while corticosterone levels were unaffected by diet type. Moreover, only cortisol responded to fasting. Overall, these results confirm that cortisol and corticosterone are not interchangeable hormones in C. talarum.

Development of a serosurveillance assay for detection of Necoclí virus exposure.

Hantavirus cardiopulmonary syndrome (HPS) has gained importance in Latin America as an emerging disease, with reports of about 4000 HPS cases; however, this is probably an underestimate because of limited surveillance programs and diagnostic tools to confirm HPS. In order to address this issue and develop better serosurveillance capability, we evaluated three recombinant peptides from the Necoclí virus (NECV) nucleocapsid in antibody-capture ELISA. We cloned and expressed antigens representing the whole NECV nucleocapsid protein (NECV-rN), the immunodominant domain (NECV-rN100), and a serospecific domain (NECV-rN428), and then we compared these antigens in ELISA to detect IgG antibodies to NECV in human sera. We evaluated human sera collected during two epidemiological studies from the area where NECV was discovered. The first group included 609 sera from healthy individuals, and the second one included 89 samples from patients with undifferentiated febrile illness. In these two groups, hantavirus infection had previously been determined by the presence of IgG to Maciel virus (MCLV), a hantavirus closely related to NECV. The number of IgG-positive sera was higher using the Necoclí ELISA with the rN100 protein, which detected antibodies in a higher percentage of healthy individuals, 129/609 (21.2%), as well as in febrile patients, 11/89 (12.3%). In contrast, using MCLV ELISA, 8 of 609 (1.3%) and 4 of 89 (4.5%) samples from healthy and febrile patients, respectively, were seropositive. The agreement between the NECV and MCLV ELISA assays was ≥ 82.3%; however, the kappa indices were weak but statistically significant for rN (0.251 CI; 0.138-0.365) and rN100rN (0.153 CI; 0.084-0.223). The weak kappa indices were attributed to decreased MCLV ELISA assay sensitivity. These results suggest that NECV rN and rN100 have increased specificity and could be further validated for improved diagnosis of hantavirus infections.

Epizootological study on Toxoplasma gondii in zoo animals in the Czech Republic.

Toxoplasma gondii is protozoan parasite with ability of causing disease in wide-spectrum of animals; many species of animals in captivity died of clinical toxoplasmosis. The monitoring of T. gondii antibodies in zoo animals can be an important indicator of T. gondii circulation in zoo. The aim of this study was to examine sera of animals from eight Czech zoos by latex agglutination test with statistical evaluation and detect T. gondii DNA in stray cats and rodents captured in the zoos. T. gondii antibodies were detected in 33% of 1043 zoo animals without statistical difference between birds (27%, n = 74) and mammals (33%, n = 969). In birds, the chance to be infected with T. gondii was higher in Accipitriformes (71%) compared to Pelecaniformes (6%) (p < 0.0001). In mammals, the chance to be infected with T. gondii was higher in Carnivora (63%) compared to Cetarodactyla (30%), Perissodactyla (26%), Primates (28%) and Rodentia (13%) (p < 0.0001) and higher in Felidae (70%) compared to Bovidae (28%) and Equidae (28%) (p < 0.0001). Mammals with carnivore/scavenger way of feeding were in a higher risk of T. gondii infection compared to herbivores and omnivores (p < 0.0001). T. gondii DNA was detected in tissue of one stray cat while in none of 77 rodents caught in zoo. This study is the first report on toxoplasmosis in zoos from the Czech Republic including seroepidemiology and molecular detection.

Rodent Abundance and Hantavirus Infection in Protected Area, East-Central Argentina.

We captured 3 hantavirus rodent hosts in Otamendi Natural Reserve, Argentina, during 2007-2012. Hantavirus antibodies were found only in Akodon azarae grass mice, mainly in males and old animals. Higher abundance of this species was associated with warm and rainy weather and high water levels, which peaked after a strong El Niño event.

Leishmania infection in rodents in Greece.

OBJECTIVE: To investigate the prevalence of Leishmania infection in rodents from various areas of northern Greece. METHODS: Ninety-seven rodents (66 Mus musculus, 19 Rattus norvegicus and 12 R. rattus) were collected during pest control programmes and examined by cytology (spleen and liver smears), serology (ELISA) and PCR (real-time and gel-based) for Leishmania. Date, environment, sex, existence of dogs in the close environment were recorded for each rodent. RESULTS: All cytological preparations were negative, whereas specific IgG was detected in 54.5% in total; 70% of R. norvegicus; 50% of R. rattus; and 50% of M. musculus. In at least one molecular method, 19.6% of the samples in total were positive: 25% of R. rattus, 24% of M. musculus, but no R. norvegicus was found positive. Environment (semi-urban areas, P = 0.037) and species (M. musculus, P = 0.032) were associated with positive PCR. All infected animals showed evidence of low parasite burden, demonstrated by the negative cytological examinations and the high Ct values observed in real-time PCR. CONCLUSION: Due to the proximity of rodents to humans and dogs, these animals may be important in the epidemiology of leishmaniosis, especially if proven that they can infect sand flies.

Serological and PCR investigation of Yersinia pestis in potential reservoir hosts from a plague outbreak focus in Zambia.

BACKGROUND: Plague is a bacterial zoonotic disease, caused by Yersinia pestis. Rodents are the natural hosts with fleas as the vehicle of disease transmission. Domestic and wild dogs and cats have also been identified as possible disease hosts. In Zambia, plague outbreaks have been reported in the Southern and Eastern regions in the last 20 years. Based on these observations, Y. pestis could possibly be endemically present in the area. METHODS: To substantiate such possibility, sera samples were collected from rodents, shrews, dogs and cats for detection of antibodies against Fraction 1 gene (Fra1) of Y. pestis while organs from rodents and shrews, and fleas from both dogs and rodents were collected to investigate plasminogen activator gene (pla gene) of Y. pestis using ELISA and PCR respectively. RESULTS: A total of 369 blood samples were collected from domestic carnivores, shrews and domestic and peri-domestic rodents while 199 organs were collected from the rodents and shrews. Blood samples were tested for antibodies against Fra1 antigen using ELISA and 3% (5/165) (95% CI 0.99-6.93%) dogs were positive while all cats were negative. Of 199 sera from rodents and shrews, 12.6% (95% CI 8.30-17.98%) were positive for antibodies against Fra1 using anti-rat IgG secondary antibody while using anti-mouse IgG secondary antibody, 17.6% (95% CI 12.57-23.60%) were positive. PCR was run on the organs and 2.5% (95% CI 0.82-5.77%) were positive for plasminogen activator gene of Y. pestis and the amplicons were sequenced and showed 99% identity with Y. pestis reference sequences. All 82 fleas collected from animals subjected to PCR, were negative for pla gene. The specific rat-flea and dog-flea indices were 0.19 and 0.27 respectively, which were lower than the level required to enhance chances of the disease outbreak. CONCLUSIONS: We concluded that plague was still endemic in the area and the disease may infect human beings if contact is enhanced between reservoir hosts and flea vectors. The lower specific rodent-flea Indices and absence of Y. pestis in the potential vectors were considered to be partly responsible for the current absence of plague outbreaks despite its presence in the sylvatic cycle.

Leptin plasma concentrations, leptin gene expression, and protein localization in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal axes of the European beaver (Castor fiber).

The European beaver (Castor fiber) is the largest seasonal free-living rodent in Eurasia. Since the physiology and endocrine system of this species remains unknown, the present study aimed to determine plasma leptin concentrations and the expression of the leptin gene and protein in the hypothalamic-pituitary-gonadal and hypothalamic-pituitary-adrenal (HPG and HPA) axes of beavers during breeding (April), postbreeding (July), and prebreeding (November) seasons. Leptin plasma concentrations did not change in females, whereas in males, leptin plasma concentrations were higher in July than those in April. The presence of leptin mRNA and protein was found in all examined tissues. In females, leptin mRNA expression in the hypothalamus, pituitary, ovaries, and myometrium was markedly higher in July than that in April. In males, leptin mRNA levels varied across the examined tissues of the HPG and HPA. Leptin synthesis increased in the hypothalamus during breeding and postbreeding seasons, but seasonal changes were not observed in the pituitary. In turn, testicular leptin levels were higher during breeding and prebreeding stages. Seasonal differences in the concentrations of leptin mRNA were also observed in the adrenal cortex. In males, leptin mRNA levels were higher in November than those in April or July. In females, leptin synthesis increased in the adrenal cortex during pregnancy relative to other seasons. This is the first ever study to demonstrate seasonal differences in leptin expression in beaver tissues, and our results could suggest that leptin is involved in the regulation of the HPG and HPA axes during various stages of the reproductive cycle in beavers.

Identification of Blood Meals from Potential Arbovirus Mosquito Vectors in the Peruvian Amazon Basin.

The transmission dynamics of many arboviruses in the Amazon Basin region have not been fully elucidated, including the vectors and natural reservoir hosts. Identification of blood meal sources in field-caught mosquitoes could yield information for identifying potential arbovirus vertebrate hosts. We identified blood meal sources in 131 mosquitoes collected from areas endemic for arboviruses in the Peruvian Department of Loreto by sequencing polymerase chain reaction amplicons of the cytochrome b gene. Psorophora (Janthinosoma) albigenu, Psorophora (Grabhamia) cingulata, Mansonia humeralis, Anopheles oswaldoi s.l., and Anopheles benarrochi s.l. had mainly anthropophilic feeding preferences; Aedes (Ochlerotatus) serratus, and Aedes (Ochlerotatus) fulvus had feeding preferences for peridomestic animals; and Culex (Melanoconion) spp. fed on a variety of vertebrates, mainly rodents (spiny rats), birds, and amphibians. On the basis of these feeding preferences, many mosquitoes could be considered as potential enzootic and bridge arbovirus vectors in the Amazon Basin of Peru.

A putative low-carbohydrate ketogenic diet elicits mild nutritional ketosis but does not impair the acute or chronic hypertrophic responses to resistance exercise in rodents.

We examined whether acute and/or chronic skeletal muscle anabolism is impaired with a low-carbohydrate diet formulated to elicit ketosis (LCKD) vs. a mixed macronutrient Western diet (WD). Male Sprague-Dawley rats (9-10 wk of age, 300-325 g) were provided isoenergetic amounts of a LCKD or a WD for 6 wk. In AIM 1, basal serum and gastrocnemius assessments were performed. In AIM 2, rats were resistance exercised for one bout and were euthanized 90-270 min following exercise for gastrocnemius analyses. In AIM 3, rats voluntarily exercised daily with resistance-loaded running wheels, and hind limb muscles were analyzed for hypertrophy markers at the end of the 6-wk protocol. In AIM 1, basal levels of gastrocnemius phosphorylated (p)-rps6, p-4EBP1, and p-AMPKα were similar between diets, although serum insulin (P < 0.01), serum glucose (P < 0.001), and several essential amino acid levels (P < 0.05) were lower in LCKD-fed rats. In AIM 2, LCKD- and WD-fed rats exhibited increased postexercise muscle protein synthesis levels (P < 0.0125), but no diet effect was observed (P = 0.59). In AIM 3, chronically exercise-trained LCKD- and WD-fed rats presented similar increases in relative hind limb muscle masses compared with their sedentary counterparts (12-24%, P < 0.05), but there was no between-diet effects. Importantly, the LCKD induced "mild" nutritional ketosis, as the LCKD-fed rats in AIM 2 exhibited ∼1.5-fold greater serum ß-hydroxybutyrate levels relative to WD-fed rats (diet effect P = 0.003). This study demonstrates that the tested LCKD in rodents, while only eliciting mild nutritional ketosis, does not impair the acute or chronic skeletal muscle hypertrophic responses to resistance exercise.

The Effect of Bromodeoxyuridine on Spontaneous Sister Chromatid Exchange Frequency in Rabbit (Oryctolagus cuniculus) and Coypu (Myocastor coypu) Chromosomes.

The sister chromatid exchange test is regarded as a highly sensitive cytogenetic assay. It measures chromosome sensitivity to particular damage factors and provides information on control and repair mechanism performance. It is instrumental in the early identification of the effects of noxious factors present in the habitat. This investigation was aimed at identifying sister chromatid exchange sites in coypu and rabbit chromosomes, as well as determining the spontaneity of the process by applying different BrdU doses. The chromosomes were obtained from an in vitro culture of blood lymphocytes, supplemented with 4 different BrdU doses: 0.25/0.5/1.0/2.5 µg/ml in order to identify spontaneous sister chromatid exchanges in both animal species. The chromosomes were stained according to the FPG method. Spontaneous SCEs were observed in coypu at a concentration of 1.0 µg/ml, and in rabbits at 0.5 µg/ml. The mean SCE/cell incidence was 1.41±1.15 in coypu, and 2.69±2.14 in rabbits. Differences in SCE incidence were identified between the analysed animal species and the applied BrdU doses.

Molecular Identification of Food Sources in Triatomines in the Brazilian Northeast: Roles of Goats and Rodents in Chagas Disease Epidemiology.

We used the gut contents of triatomines collected from rural areas of Ceará State, northeastern Brazil, to identify their putative hosts via vertebrate cytb gene sequencing. Successful direct sequencing was obtained for 48% of insects, comprising 50 Triatoma brasiliensis, 7 Triatoma pseudomaculata, and 1 Rhodnius nasutus. Basic local alignment search tool (BLAST) procedure revealed that domestic animals, such as chickens (Gallus gallus) and goats (Capra hircus), are the main food source, including in sylvatic environment. Native hosts were also detected in peridomestic environment such as reptiles (Tropidurus sp. and Iguana iguana) and the Galea spixii (Rodentia: Caviidae). The role of goats and Galea spixii in Chagas disease epidemiology calls for further studies, because these mammals likely link the sylvatic and domestic Trypanosoma cruzi cycles.

[Parental Care and Testosterone Secretion in Forest Rodent Males: Sensitization and Androgenic Stimulation of Parental Behavior].

The reaction of males of three forest rodent species (Myodes clethrionomys, M. rutilus, Apodemus uralensis) to young animals in comparison with their dimensional characteristics and androgenization level was studied. Demonstration of parental care was detected in males of two vole species (M. clethrionomys and M. rutilus) in case of regular contacts with them (sensitization effect). It was demonstrated that the testosterone concentration in the blood serum, as well as the testosterone content in the testicles of the M. clethrionomys males (demonstrating the parental care), was higher than in the sample of males inclined to infanticide. An increased testosterone content in the testicles and blood serum was also found in the M. rutilus males that had contact with young animas. Neither demonstration of parental care nor significant differences in the testosterone concentration in the testicles and blood serum were detected in the A. uralensis males.