Effect of recombinant bovine somatotropin (rbST) on cytoplasmic maturation of bovine oocytes and their developmental competence in vitro

The objectives of this study were to evaluate the effects of recombinant bovine somatotropin (rbST) on the nuclear and cytoplasmic maturation of bovine oocytes and their further developmental competence to blastocysts in vitro. We analyzed the mitochondrial activity and concentration of intracellular stored calcium ([Ca(2+)](is)) in matured oocytes and the morphology and chromatin status of produced embryos after in vitro fertilization. Cumulus-oocyte complexes were incubated in TCM 199 containing 10% fetal calf serum (control medium 1: CM 1) or 10% estrus cow serum (control medium 2: CM 2). The culture medium of the treatment groups was modified by supplementation of the control medium with 10 ng/ml rbST (CM 1A and CM 2A), 10(6)/ml granulosa cells (CM 1B and CM 2B), or 10 ng/ml rbST plus 10(6)/ml granulosa cells (CM 1C and CM 2C). No differences were observed in the percentages of oocytes reaching metaphase II between the groups. However, the proportion of blastocysts was highest in treatment groups CM 1C and CM 2C (P<0.05). The type of serum did not alter the positive effect of rbST on the developmental competence of embryos. The fluorescence intensity of metabolically active mitochondria measured by intensity per oocyte (Em 570) after MitoTracker CMTM Ros Orange labeling was significantly increased in oocytes matured in the presence of 10 ng/ml rbST and granulosa cells (309.21 vs. 119.97 microA; P<0.01). In parallel, the concentration of [Ca(2+)](is) in oocytes, determined using fluorophore chlortetracycline, was significantly decreased (0.85 +/- 0.02 vs. 0.97 +/- 0.03 AU; P<0.05). Based on these results, we concluded that rbST, in interaction with granulosa cells stimulates the oxidative activity of ooplasmic mitochondria and decreases the content of [Ca(2+)](is) in oocytes. These facts support the hypothesis that somatotropin influences the developmental competence of bovine oocytes during maturation in vitro, and this effect can be modulated by granulosa cells.     

Agronomic evaluation of seedlings from crosses between the main Spanish olive cultivar ‘Picual’ and two wild olive trees

Summary

Until recently, olive breeding programmes have been based exclusively on cultivated olive germplasm (Olea europaea subsp. europaea var. europaea), in contrast to breeding in other fruit crops where the use of wild relatives has been widely reported. In this study, ten agronomic traits were evaluated in two progenies derived from controlled crosses between the Spanish olive cultivar ‘Picual’ (female) and two wild (O. europaea subsp. europaea var. sylvestris) genotypes (males). The results of this evaluation were compared with the progenies of crosses between ‘Picual’ (female) and the three cultivars, ‘Sikitita’, ‘Meski’, and ‘Zaity’ (male). The two ‘Picual’ × wild genotype progenies had the highest mean values for vigour traits (i.e., tree height and trunk diameter). Progenies from both ‘Picual’ × wild genotype crossess also showed the highest percentages of trees (53.8% and 37.5%) with a short juvenile period, compared to the progenies from crosses between ‘Picual’ and each of the three cultivars ‘Sikitita’, ‘Meski’, and ‘Zaity’ (0%, 5%, and 3.6%, respectively). Significant differences were also observed between progenies in fruit traits as well as in oil contents and fruit weights. Progenies from both crosses with wild olive showed lower values for the fruit traits evaluated than the cultivated olive progenies. However, significant improvements were achieved compared to fruit traits in the wild parents. The implications of these results for the future use of wild germplasm in olive breeding programmes are discussed.     

Prevalence and genotypes of Giardia duodenalis in dairy and beef cattle in farms around Charlottetown, Prince Edward Island, Canada

Prevalence of Giardia duodenalis in dairy and beef cattle on farms around Charlottetown, Prince Edward Island (Canada) was determined by analyzing feces using direct immunofluorescence antibody microscopy. Genotypes were determined by 16S-rRNA sequencing. Fecal samples (n = 892) were collected from adult cattle in dairy tie-stall, dairy free-stall, and beef herds (10 herds each), and from calves (n = 183) from 11 dairy farms. Prevalence rates were 38% and 51% in cows and calves, respectively. Giardia duodenalis was present in all dairy herds, in 9/10 beef herds and in calves from 10/11 herds examined. Prevalence rates were 40% and 41% for cows in tie- and free-stall herds, respectively, and 27% for beef cows. Zoonotic Assemblage A was found in 12.2% of calves concomitantly infected with Assemblage E. All successfully sequenced samples (114/128) from cows corresponded to Assemblage E. Giardia duodenalis is highly prevalent in cattle herds in Prince Edward Island and Assemblage A in calves is a potential public health concern.     

A Simple Flow-through System for Toxicity Testing with Daphnids

A simple and accurate flow-through system was developed for toxicity evaluation of biodegradable substances, wastewaters, and surface waters. The chronic toxicity of phenol to the daphnid Daphnia magna was studied during a 21 d exposure period, first using a semi-static and later a flow-through test. The flow- through system was advantageous especially when lower concentrations of phenol were examined. Its use provided a constant concentration of phenol in all tested samples. Exposure to phenol showed a similar influence on both survival and reproduction of daphnids; the IC25 value was 3.18 mg L-1.     

Past and present potential of the Adriatic deep sea sediments to produce methane hydrates

Journal of Soils and Sediments - There is a growing understanding that methane hydrates (MHs) distributed globally in permafrost and deep sea sediments present an enormous unconventional reservoir...     

Model system for mechanistic study of catalytic bleaching of cotton

We have developed a homogeneous model system to study the mechanism of hydrogen peroxide bleaching using [Mn₂O₃(N,N′,N″-trimethyl-1,4,7-triazacyclononane)₂](PF₆)₂ (MnTMTACN) as catalyst. The primary model pigment examined is morin (3,5,7,2′,4′-pentahydroxyflavone) owing to its presence in native cotton fiber. Additionally, a series of model compounds with systematic structural differences are examined in order to facilitate the development of a mechanistic understanding of the bleaching system. The pigment oxidative degradation reaction is monitored by UV-Vis spectrophotometry. The influence of pH is examined in both homogeneous and heterogeneous model systems. The use of MnTMTACN catalyst enables low-temperature hydrogen peroxide bleaching of cotton fabric at slightly lower pH values.     

Canine babesiosis in Slovenia: molecular evidence of Babesia canis canis and Babesia canis vogeli

Canine babesiosis, caused by intraerythrocytic Babesia spp., is a tick-borne disease of worldwide importance. No information on canine babesiosis has been documented in Slovenia. Therefore, 238 dogs admitted to the Small animal clinic in Ljubljana from the years 2000 to 2002 were tested for the presence of babesial parasites in the blood. Based on clinical, microscopic and molecular investigations, 14 dogs (5.9%) were determined as being infected with babesiae. Clinical signs relating to acute haemolysis, fever, anorexia, depression and haematological abnormalities such as anaemia and thrombocytopenia were noticed in most of the 14 infected dogs. The morphology of the parasites was indicative of Babesia canis infection. Two subspecies were detected, namely B. canis canis (11 dogs, 4.6%) and B. canis vogeli (3 dogs, 1.3%) using PCR and subsequent sequence analysis of portions of nns rRNA gene. In addition, based on nucleotide sequence analysis, the 11 isolates of B. c. canis could be subdivided into three groups, whereas the three B. c. vogeli isolates were genetically identical. The results of this study demonstrate the presence of canine babesiosis due to B. c. canis and B. c. vogeli in Slovenia.     

Occupational swine exposure and Hepatitis E virus,Leptospira, Ascaris suum seropositivity and MRSA colonization in Austrian veterinarians, 2017–2018—A cross‐sectional study

We investigated the prevalence of Hepatitis E Virus (HEV), Leptospira and Ascaris suum (A. suum) seropositivity, and of nasal methicillin‐resistant Staphylococcus aureus (MRSA) colonization among Austrian practising veterinarians, and assessed the association with occupational swine livestock exposure. The 261 participants completed a questionnaire on demographics, intensity of occupational swine livestock contact and glove use during handling animals and their secretions. Participants' blood samples were tested for HEV, Leptospira and A. suum seropositivity and nasal swabs cultured for MRSA. We compared swine veterinarians (defined as >3 swine livestock visits/week) to non‐swine veterinarians (≤3 swine livestock visits/week) with regard to the outcomes through calculating prevalence ratio (PR) and 95% confidence interval (CI). Furthermore, the relationship between occupational swine livestock contact and the study outcomes was examined by age (</≥55 years) and glove usage. The prevalence of nasal MRSA colonization was 13.4% (95% CI: 9.3–17.6), of HEV seropositivity 20.8% (95% CI: 15.8–25.7) and A. suum seropositivity 44% (95% CI: 37.7–50.2). The highest anti‐leptospiral antibodies titres were 1:200 (L. hebdomadis) and 1:100 (L. autumnalis, L. caicola) found in three non‐swine veterinarians. Compared to non‐swine veterinarians, swine veterinarians were 1.9 (95% CI: 1.0–3.4) and 1.5 (95%CI: 1.0–2.3) times more likely HEV seropositive and A. suum seropositive, respectively, and 4.8 (95%CI: 2.5; 9.3) times more likely nasally colonized with MRSA. Among glove‐using veterinarians, occupational swine contact was no longer a determinant for HEV seropositivity (PR 1.6; 95% CI: 0.8–2.9). Similar was found for A. suum seropositivity, which was no longer associated with occupational swine livestock contact in the subgroup of glove using, ≥55‐year‐old veterinarians (PR: 1.07; 95% CI: 0.4–3.3). Our findings indicate that >3 occupational swine livestock visits per week is associated with HEV and A. suum seropositivity and nasal MRSA colonization and that glove use may play a putative preventive role in acquiring HEV and A. suum. Further analytical epidemiological studies have to prove the causality of these associations.     

A Qualitative Multi-Attribute Model for The Multifunctional Assessment of ��Streuobst Stands�� in NE Slovenia

Streuobst stands, i.e., tall fruit trees on vigorous rootstock on traditional grassland, represent an important source of raw material for the processing industry and for traditional fruit processing on family-run farms. Apart from production aspects, the high-stem orchards also play a role in the conservation of the traditional landscape, and indirectly in maintenance of the viability of rural areas. In this paper, a qualitative multi-attribute model for the assessment of Streuobst stands with respect to their multifunctional characteristics is presented. The assessment is based on four groups of attributes: (1) production criteria (percentage of missing trees), (2) biodiversity (fruit species and varieties, artificial human intervention), (3) landscape diversity (visual appearance, eco-diversity and erosion protection), and (4) function of the stand (row or individual trees, countryside appearance). The assessment is based on the aggregation of input attribute values to an overall assessment through user-defined decision rules. The model was applied to 85 sample stands in NE Slovenia. The assessment shows that most of the stands (48) were rated as ??very poor?? or ??poor??, mainly as a result of poor cultivation and lack of maintenance.