Administration of Lupinus albus Gamma Conglutin (Cγ) to n5 STZ Rats Augmented Ins-1 Gene Expression and Pancreatic Insulin Content

Several studies support the health-promoting benefits of lupins, particularly lupin proteins. It has been demonstrated that Lupinus albus gamma conglutin (Cγ) protein lowered blood glucose levels; thus, Cγ showed promise as a new anti-diabetic compound for type 2 diabetes (T2D) treatment. The aim of this study was to evaluate the effect of Cγ on Ins-1 gene expression and on pancreatic insulin content in streptozotocin-mediated diabetic rats. Cγ was isolated from Lupinus albus seeds. Its identification was confirmed with polyacrylamide gel electrophoresis under native and denaturing conditions. We used streptozotocin (STZ) to induce T2D on the 5th day of life of newborn male Wistar rats (n5-STZ). After 20 weeks post-induction, these animals (glycemia?>?200 mg/dL) were randomly assigned to three groups that received the following one-week treatments: vehicle, 0.90 %?w/v NaCl (n5 STZ-Ctrl); glibenclamide, 10 mg/kg (n5 STZ-Glib); or Cγ, 120 mg/kg (n5 STZ-Cγ). Glucose and insulin levels were measured before and after treatment. Ins-1 gene expression was quantified using real time polymerase chain reaction and the pancreatic insulin content was evaluated with immunohistochemistry. Post-treatment, the n5 STZ-Cγ and n5 STZ-Glib groups showed reductions in glucose, increments in serum insulin, and increases in Ins-1 gene expression and beta cell insulin content compared to the n5 STZ-Ctrl group. The results showed that Cγ had beneficial effects on Ins-1 gene expression and pancreatic insulin content. These biological effects of Cγ strengthen its promising potential as a nutraceutical and/or new agent for controlling hyperglycemia.     

Cattle Drive Salmonella Infection in the Wildlife–Livestock Interface

The genus Salmonella is found throughout the world and is a potential pathogen for most vertebrates. It is also the most common cause of food‐borne illness in humans, and wildlife is an emerging source of food‐borne disease in humans due to the consumption of game meat. Wild boar is one of the most abundant European game species and these wild swine are known to be carriers of zoonotic and food‐borne pathogens such as Salmonella. Isolation of the pathogen, serotyping and molecular biology are necessary for elucidating epidemiological connections in multi‐host populations. Although disease management at population level can be addressed using a number of different strategies, such management is difficult in free‐living wildlife populations due to the lack of experience with the wildlife–livestock interface. Herein, we provide the results of a 4‐year Salmonella survey in sympatric populations of wild boar and cattle in the Ports de Tortosa i Beseit National Game Reserve (NE Spain). We also evaluated the effects of two management strategies, cattle removal and increased wild boar harvesting (i.e. by hunting and trapping), on the prevalence of the Salmonella serovar community. The serovars Meleagridis and Anatum were found to be shared by cattle and wild boar, a finding that was confirmed by 100% DNA similarity patterns using pulse field gel electrophoresis. Cattle removal was more efficient than the culling of wild boar as a means of reducing the prevalence of shared serotypes, which underlines the role of cattle as a reservoir of Salmonella for wild boar. To our knowledge, this is the first attempt to manage Salmonella in the wild, and the results have implications for management.     

Clonal diversity of Staphylococcus aureus originating from the small ruminants goats and sheep

Staphylococcus aureus is an important pathogen in humans and many animal species. The prevalence of different clonal types in animal species remains largely unknown. We analyzed 267 S. aureus from intramammary infections in goats (47) and sheep (220) by spa typing, multi-locus sequence typing (MLST) and antimicrobial susceptibility. The most frequent spa types in goats were t337 (N=9), t759 (N=6) and t1534 (N=5). Sheep isolates mainly belonged to spa types t1534 (N=72), t2678 (N=29) and t3576 (N=20). Eighteen novel spa-types were observed; two from goat strains, 13 from sheep and three in both species. The majority of the goat strains grouped in MLST CC133 (N=10) and ST522 (N=10), followed by CC9 (N=9), while the majority of the sheep strains were of ST522 (N=108) followed by CC133 (N=86) and CC130 (N=11). Nine new MLST types were detected; three in goat and sheep isolates (ST1739, ST1758 and ST1780), two identified in goats only (ST1740 and ST2061) and four in sheep only (ST1742, ST1743, ST1781 and ST2011). Strains showed resistance below 20% against penicillin and tetracycline; a strong association between CC-types and penicillin resistance was observed. No resistance was detected to cefoxitin, quinupristin-dalfopristin, rifampicin and vancomycin. This study suggests that ST522 is the most common S. aureus clone associated with small ruminants followed by CC133.     

Experimental infection with Mycobacterium caprae in goats and evaluation of immunological status in tuberculosis and paratuberculosis co-infected animals

Tuberculosis in goats (caused by Mycobacterium caprae and M. bovis) has become a significant concern in recent years because of its high prevalence in certain caprine herds in Spain and other European countries, and also due to the potential transmission to other animals and human beings. In the present study, a transthoracic model of tuberculosis infection was performed on goats. Animals were selected based on the serological response used to detect paratuberculosis in goats (negative and positive results). The kinetics of the immune response was evaluated using the interferon-γ (IFN-γ) assay, skin tests and serology of paratuberculosis during nine months post-challenge. At the end of the study the animals were necropsied, tuberculosis-lesions were scored and culture (M. caprae and M. avium subsp. paratuberculosis) was performed to determine the true infection status. Animals were positive to the IFN-γ assay 15 days post-challenge and the values were fluctuating throughout the study. A varied performance of the assay was observed between tuberculosis and tuberculosis-paratuberculosis mixed infection regarding both the number of positive results and the OD values obtained after stimulation with bovine and avian PPDs. Furthermore, the single intradermal comparative cervical tuberculin test did not detect all M. caprae-infected animals. At necropsy, a positive correlation between pathology score and bovine PPD specific IFN-γ response was found.     

Mechanisms of resistance and susceptibility to experimental visceral leishmaniosis: BALB/c mouse versus syrian hamster model

ABSTRACT: Several animal models have been established to study visceral leishmaniosis (VL), a worldwide vector-borne disease affecting humans and domestic animals that constitutes a serious public health problem. BALB/c mice and Syrian hamsters are the most widely used experimental models. In this paper, we summarize the advantages and disadvantages of these two experimental models and discuss the results obtained using these models in different studies of VL. Studies using the BALB/c mouse model have underscored differences between the liver and spleen in the course of VL, indicating that pathological evaluation of the visceral organs is essential for understanding the immune mechanisms induced by Leishmania infantum infection. The main goal of this review is to collate the relevant literature on Leishmania pathogenesis into a sequence of events, providing a schematic view of the main components of adaptive and innate immunity in the liver and spleen after experimental infection with L. infantum or L. donovani. This review also presents several viewpoints and reflections about some controversial aspects of Leishmania research, including the choice of experimental model, route of administration, inoculum size and the relevance of pathology (intimately linked to parasite persistence): a thorough understanding of which is essential for future VL research and the successful development of efficient control strategies for Leishmania spp.     

Study of peripheral blood cell populations involved in the immune response of goats naturally infected with Mycobacterium caprae

Tuberculosis in goats caused by Mycobacterium bovis and Mycobacterium caprae has noteworthy sanitary and economic implications. Current diagnostic assays are based on cellular immunity and although they have demonstrated a high sensitivity, some animals remain undetected. In the present study, flow cytometry has been used to determine changes in CD4+, CD8+ and CD25+ T cell populations in peripheral blood from naturally infected goats. Proportion of lymphocytes producing PPD-specific interferon-gamma (IFN-γ) was calculated and an ELISA for detection of PPD-specific IFN-γ was performed to measure the cytokine in plasma. The infected goats showed percentages of CD4+ T cells between 27.31% and 47.23% and there were not significant differences (p=0.113) with the non-infected control goats although the mean percentage was lower in this group. Regarding CD8+ T cells, a higher percentage was observed in healthy goats compared to controls (p=0.081). The mean percentage of lymphocytes expressing CD25 without antigen stimulation (30.65±3.91) was higher in lesion and/or culture-positive animals than in the controls (21.84±1.21; p=0.053). The percentage of CD4+/IFN+ T cell population stimulated with bovine PPD was a reliable marker of infection, since the mean percentage in the infected goats was significantly higher than in the controls (p<0.05). Tuberculosis in goats caused by M. caprae induced changes in cellular populations similar to those described for M. bovis in cattle.     

Supercritical CO2 extraction and purification of compounds with antioxidant activity

Supercritical fluid extraction (SCFE), based on the utilization of a fluid under supercritical conditions, is a technology suitable for extraction and purification of a variety of compounds, particularly those that have low volatility and/or are susceptible to thermal degradation. The interest in SCFE is promoted by legal limitations of conventional solvents for food and pharmaceutical uses. The physicochemical properties of supercritical CO2 (higher diffusivity, lower viscosity, and lower surface tension than conventional solvents) facilitate mass transfer and allow an environmentally friendly operation. This article presents a comprehensive compilation of data on the supercritical CO2 extraction of antioxidant compounds from vegetal materials, with particular attention to those of a phenolic nature. Aspects concerning the supercritical operation for extraction and fractionation of antioxidants compounds are considered, including equilibrium solubility of pure compounds and effects of the operational conditions on the antioxidant activity of isolated fractions. The data are compared to those reported for synthetic antioxidants and natural extracts obtained by conventional solvent extraction from vegetal matrices.     

Abundance and phenotypic diversity of Escherichia coli isolates with diminished susceptibility to expanded-spectrum cephalosporins in faeces from healthy food animals after slaughter

Antimicrobial resistance (AR) is an increasing phenomenon but its quantitative estimation remains controversial. The classical resistance percentage approach is not well suited to detect either emergence or low levels resistance. One option is to shift the focus from strains to hosts. This approach is applied to test for phenotypic diversity associated with diminished susceptibility to expanded-spectrum cephalosporins (DSESC) in faecal Escherichia coli from healthy food animals in Spain.

We performed E. coli enumeration in faecal samples of broilers (82 pooled samples) and pigs (80 pooled samples) at the slaughterhouse level, using Coli-ID plates alone and supplemented with cefotaxime at two levels (1 and 8 μg/ml). Antimicrobial susceptibility of isolates was tested by the agar diffusion method. Clustering was carried out using these numerical values and Ward and UPGMA methods.

When using plates supplemented with 1 μg/ml of cefotaxime for DSESC E. coli detection, 93% (76/82) of broiler pooled samples and 36% (29/80) pig pooled samples tested positive. When using 8 μg/ml of cefotaxime, 67% (55/82) of broilers and 13% (10/80) of pigs were positive. Nevertheless, the relative abundance of this phenotype was low in both animal species (range 0–4.3%). Irrespective of the clustering method (Ward or UPGMA), a noticeable phenotypic diversity was detected, especially from the plates containing 1 μg/ml of cefotaxime.

We concluded that: (a) E. coli with phenotype DSESC are common in broilers and pigs but are less frequent in pigs, and (b) the host approach is the most appropriate method for antimicrobial resistance assessment when null or very low levels of antimicrobial resistant bacteria are expected.     

Phylogenetic networks to study the origin and evolution of porcine circovirus type 2 (PCV2) in Cuba

Porcine circovirus type 2 (PCV2) is the essential etiological infectious agent of postweaning multisystemic wasting syndrome (PMWS), which is considered one of the most economically important swine diseases worldwide. In this study, a comparison between methodologies based on classical phylogenetic trees and networks to infer the origin of PCV2 in Cuba was performed. In addition, the mechanisms supporting the genetic variability of Cuban PCV2 populations were investigated. A retrospective study, using pig sera collected in Cuba from 1993 to 2004, to evaluate the presence of PCV2 genome and PCV2-specific antibodies was also conducted and revealed a lack of evidence of PCV2 infection in Cuban swine from years 1993 to 2004. A total of 24 complete Cuban PCV2 sequences collected between 2005 and 2009 from different regions of the country were analyzed. Three classical methods of phylogenetic analysis, namely Neighbour-Joining, Maximum Parsimony and Bayesian Inference, as well as haplotype network construction, were used. Whereas the classical phylogenetic trees suggested different origins for the Cuban PCV2 strains, the haplotype network revealed a direct connection between all the Cuban sequences in agreement with the obtained epidemiological and viral sequence data. Moreover, the importation of pigs carried out in 2005 from the Quebec-Ontario region, Canada, seems to be the most likely origin of PCV2 in Cuba. Likewise, the genetic variability of Cuban PCV2 sequences was supported by geographic segregation and positive selection pressure with estimated rates of nucleotide substitution on the order of 3.12×10(-3) and 6.57×10(-3) substitutions/site/year, which are closer to those reported for RNA viruses.