Prevalence of Giardia duodenalis and Cryptosporidium spp. in dogs from different living conditions in Uberlândia, Brazil

Infection rates with Giardia duodenalis and Cryptosporidium spp. were compared among dogs living under different conditions. Stool samples (n = 433) collected from dogs of different ages, gender, living conditions and origin were analyzed using three techniques, i.e., centrifugal flotation in zinc sulfate solution, centrifugal flotation in sucrose solution, and methylene blue gram safranin staining. Eighty-nine of the samples were from stay dogs living in shelters run by animal protection societies, 199 were from kennels and 122 from households. A total of 119 (29.0%) had G. duodenalis cysts and six (1.4%) were positive for Cryptosporidium spp. oocysts. Dogs from kennels were most frequently affected by G. duodenalis (49.7%) while those from shelters showed a higher prevalence of Cryptosporidium spp. (2.2%). A significant difference (p < or = 0.05) was observed between immature dogs and adults only with respect to Giardia infection. There was no significant difference between the gender with regard to the presence of either protozoan.     

Biomimetic Pathways for Assembling Inorganic Thin Films

Living organisms construct various forms of laminated nanocomposites through directed nucleation and growth of inorganics at self-assembled organic templates at temperatures below 100°C and in aqueous solutions. Recent research has focused on the use of functionalized organic surfaces to form continuous thin films of single-phase ceramics. Continuous thin films of mesostructured silicates have also been formed on hydrophobic and hydrophilic surfaces through a two-step mechanism. First, under acidic conditions, surfactant micellar structures are self-assembled at the solid/liquid interface, and second, inorganic precursors condense to form an inorganic-organic nanocomposite. Epitaxial coordination of adsorbed surfactant tubules is observed on mica and graphite substrates, whereas a random arrangement is observed on amorphous silica. The ability to process ceramic-organic nanocomposite films by these methods provides new technological opportunities.     

The Seismic Structure of the Sun

Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of chemical inhomogeneity that is too severe in the model, perhaps owing to inaccurate modeling of gravitational settling or to neglected macroscopic motion that may be present in the sun. Accurate knowledge of the sun's structure enables inferences to be made about the physics that controls the sun; for example, through the opacity, the equation of state, or wave motion. Those inferences can then be used elsewhere in astrophysics.     

The confidential enquiry into perioperative equine fatalities (CEPEF): mortality results of Phases 1 and 2

Objectives To document the equine perioperative mortality rate and to highlight any factor associated with an increased risk of death up to 7 days after anaesthesia. Study design A prospective observational epidemiological multicentre study. Methods Data were recorded from all equidae undergoing general anaesthesia in 62 clinics. Power calculations indicated that 45 000 cases were required to detect the significance of important variables. Details of each horse, operation, anaesthetic agents and clinic personnel were recorded. Outcome at 7 days was recorded as: alive, put to sleep (PTS) or dead. Data were analysed by a standard multilevel logistic regression approach, considering the effects of clustering at the level of clinic. Results Data were collected from 41 824 cases over 6 years. A total of 39 025 (93.3%) were alive on day 7 and 785 were dead giving an overall death rate of 1.9% (95% CI: 1.8–2.0) and 2014 (4.8%) were PTS. About 5846 horses undergoing emergency abdominal surgeries (‘colics’) were excluded from subsequent analyses. A total of 35 107 ‘noncolic’ horses were alive at 7 days and 328 dead giving a death rate for noncolics of 0.9% (95% CI: 0.8–1.0). Five hundred and forty‐three (1.5%) noncolic horses classified PTS were excluded from further analyses. There were 109 (33%) deaths from cardiac arrest or post‐operative cardiovascular collapse, with 107 (32%) from fractures and myopathies. Fracture repair, out of hours surgery, and age below 1 month was associated with increased risk of dying whereas the use of acepromazine and intravenous anaesthetic agent maintenance of anaesthesia was associated with reduced risk. Conclusions A number of potential contributors to the high risk of anaesthetic‐related mortality have been identified. Further investigation of the underlying mechanism for their apparent harmful effects and development of alternative techniques is merited.     

The global contribution of forage fish to marine fisheries and ecosystems

Forage fish play a pivotal role in marine ecosystems and economies worldwide by sustaining many predators and fisheries directly and indirectly. We estimate global forage fish contributions to marine ecosystems through a synthesis of 72 published Ecopath models from around the world. Three distinct contributions of forage fish were examined: (i) the ecological support service of forage fish to predators in marine ecosystems, (ii) the total catch and value of forage fisheries and (iii) the support service of forage fish to the catch and value of other commercially targeted predators. Forage fish use and value varied and exhibited patterns across latitudes and ecosystem types. Forage fish supported many kinds of predators, including fish, seabirds, marine mammals and squid. Overall, forage fish contribute a total of about $16.9 billion USD to global fisheries values annually, i.e. 20% of the global ex‐vessel catch values of all marine fisheries combined. While the global catch value of forage fisheries was $5.6 billion, fisheries supported by forage fish were more than twice as valuable ($11.3 billion). These estimates provide important information for evaluating the trade‐offs of various uses of forage fish across ecosystem types, latitudes and globally. We did not estimate a monetary value for supportive contributions of forage fish to recreational fisheries or to uses unrelated to fisheries, and thus the estimates of economic value reported herein understate the global value of forage fishes.     

Bacterial communities and biogeochemical transformations of iron and sulfur in a high saltmarsh soil profile

Microbial community structure in saltmarsh soils is stratified by depth and availability of electron acceptors for respiration. However, the majority of the microbial species that are involved in the biogeochemical transformations of iron (Fe) and sulfur (S) in such environments are not known. Here we examined the structure of bacterial communities in a high saltmarsh soil profile and discuss their potential relationship with the geochemistry of Fe and S. Our data showed that the soil horizons Ag (oxic–suboxic), Bg (suboxic), Cr₁ (anoxic with low concentration of pyrite Fe) and Cr₂ (anoxic with high concentrations of pyrite Fe) have distinct geochemical and microbiological characteristics. In general, total S concentration increased with depth and was correlated with the presence of pyrite Fe. Soluble + exchangable-Fe, pyrite Fe and acid volatile sulfide Fe concentrations also increased with depth, whereas ascorbate extractable-Fe concentrations decreased. The occurrence of reduced forms of Fe in the horizon Ag and oxidized Fe in horizon Cr₂ suggests that the typical redox zonation, common to several marine sediments, does not occur in the saltmarsh soil profile studied. Overall, the bacterial community structure in the horizon Ag and Cr₂ shared low levels of similarity, as compared to their adjacent horizons, Bg and Cr₁, respectively. The phylogenetic analyses of bacterial 16S rRNA gene sequences from clone libraries showed that the predominant phylotypes in horizon Ag were related to Alphaproteobacteria and Bacteroidetes. In contrast, the most abundant phylotypes in horizon Cr₂ were related to Deltaproteobacteria, Chloroflexi, Deferribacteres and Nitrospira. The high frequency of sequences with low levels of similarity to known bacterial species in horizons Ag and Cr₂ indicates that the bacterial communities in both horizons are dominated by novel bacterial species.     

Sensitivity of boreal forest carbon balance to soil thaw

We used eddy covariance; gas-exchange chambers; radiocarbon analysis; wood, moss, and soil inventories; and laboratory incubations to measure the carbon balance of a 120-year-old black spruce forest in Manitoba, Canada. The site lost 0.3 +/- 0.5 metric ton of carbon per hectare per year (ton C ha-1 year-1) from 1994 to 1997, with a gain of 0.6 +/- 0.2 ton C ha-1 year-1 in moss and wood offset by a loss of 0.8 +/- 0.5 ton C ha-1 year-1 from the soil. The soil remained frozen most of the year, and the decomposition of organic matter in the soil increased 10-fold upon thawing. The stability of the soil carbon pool ( approximately 150 tons C ha-1) appears sensitive to the depth and duration of thaw, and climatic changes that promote thaw are likely to cause a net efflux of carbon dioxide from the site.     

Biochemical serum profiles in dogs experimentally infected with Angiostrongylus vasorum (Baillet, 1866)

The biochemical profiles of crossbred dogs experimentally infected with the parasite Angiostrongylus vasorum were studied. Two groups of five dogs were experimentally inoculated with 50 and 100 third stage infective larvae (L3) of A. vasorum per kilogram of body weight. A third group of five uninfected animals were used as control. Serum from these animals were used for biochemical tests to measure total and fractioned proteins, urea, creatinine and to determine the activities of aspartate (AST), alanine (ALT) aminotransferase, gamma-glutamyl transferase (GGT), alkaline phosphatase (PAL) and creatine kinase isoenzyme MB (CK-MB). The alpha-1, alpha-2 and beta-globulins fractions showed alterations during acute phase of the infection. No modifications were observed in the biochemical profiles of ALT, AST, GGT, PAL, urea and creatinine. CK-MB was shown to be a good early indicator of cardiac injury in dogs experimentally infected with A. vasorum.     

Ovarian Responses, Hormonal Profiles and Embryo Yields in Anoestrous Ewes Superovulated with Folltropin®-V after Pretreatment with Medroxyprogesterone Acetate-releasing Vaginal Sponges and a Single Dose of Oestradiol-17β

In ruminants, superovulatory treatments started at the time of follicular wave emergence result in greater and less variable ovulatory responses and embryo yields compared with the treatments begun in the presence of a large growing antral follicle(s) from the previous waves. The progesterone–oestradiol treatment is routinely used for follicular wave synchronization in cattle. The main objective of this study was to characterize the ovarian responses, hormonal profiles and in vivo embryo production in anoestrous Rideau Arcott ewes (May‐June), which were superovulated after pretreatment with medroxyprogesterone acetate (MAP)‐releasing intravaginal sponges and a single dose of oestradiol‐17β (E₂‐17β). Six days after insertion of MAP sponges, eight ewes were given an i.m. injection of 350 μg of E₂‐17β (E₂‐17β‐treated ewes); 10 ewes were given an i.m. injection of vehicle (control ewes). Multiple‐dose Folltropin®‐V treatment, followed by the bolus injection of GnRH (50 μg i.m.), began 6 days after E₂‐17β/vehicle injection. Transrectal ovarian ultrasonography revealed that: (i) the interval between E₂‐17β/vehicle injection and regression of all follicles ≥5 to 3 mm in diameter was shorter (p < 0.01; 2.6 ± 0.4 vs 4.8 ± 0.6 days respectively); and (ii) the interval between injection and emergence of the next follicular wave was longer (p < 0.05; 5.4 ± 0.3 vs 1.2 ± 0.4 days, respectively) in E₂‐17β‐treated than in control ewes. During the 6 days after injection, the mean FSH peak concentration and basal FSH concentration were lower (p < 0.01) in E₂‐17β‐treated ewes. The mean ovulation rate and the number of recovered embryos did not differ (p > 0.05) between the two groups of ewes. However, the number of luteinized unovulated follicles per ewe, and the variability in the number of luteal structures and overall embryo yield were less (p < 0.05) in E₂‐17β‐treated compared with control ewes. In conclusion, the MAP–E₂‐17β pretreatment significantly reduced the variability in ovarian responses and embryo yields, without affecting the embryo production in superovulated anoestrous ewes.