Crayfish plague in Czechia: Outbreaks from novel sources and testing for chronic infections.

The crayfish plague pathogen Aphanomyces astaci, which is among the most studied pathogens of aquatic invertebrates, co-evolved with North American crayfish species but threatens crayfish on other continents. The pathogen causes mass mortalities, particularly in Europe. In this study we document 12 crayfish plague outbreaks that occurred from 2014 to 2019 in Czechia and, by using available molecular techniques (microsatellite and mtDNA markers), we reveal the A. astaci genotypes involved. Our results provide the first evidence of strains from genotype group D, originally associated with the host Procambarus clarkii, causing Astacus astacus and Austropotamobius torrentium mass mortalities in Czechia. Moreover, mtDNA sequencing confirmed two distinct haplotypes of the D haplogroup, indicating two independent sources of infection, presumably originating from ornamental crayfish in the pet trade or spreading from crayfish established in neighbouring countries. Genotype group A was recorded in two As. astacus mortalities, and genotype group E, associated with Faxonius limosus, in two Au. torrentium and three As. astacus mortalities. Microsatellite genotyping also reidentified the unusual genotype SSR-Up in two As. astacus outbreaks, ten years after its first documented occurrence. In addition, we tested healthy-appearing indigenous crayfish from 25 localities for potential chronic infections. No traces of A. astaci DNA were detected; chronic infections in European crayfish species thus do not seem a pervasive phenomenon in Czechia. However, their role as A. astaci latent reservoirs, especially in Pontastacus leptodactylus populations introduced to the country since the late 19th century, cannot be excluded.

Toxic and heavy metals as a cause of crayfish mass mortality from acidified headwater streams.

Mining activities are responsible for high concentrations of metals in river networks in many parts of the world. Mining activities and the resulting high loads of heavy metals interact with intensive acid rain, and often have great consequences for biodiversity. However, considering the frequently episodic nature of these heavy acid rains, there is little detailed evidence of direct impacts. In 2011 we observed a massive mortality of noble crayfish and stone crayfish in Padrtsko Special Area of Conservation (SAC) in the Brdy Mountain region of the Czech Republic. Based on concentrations of metals (Al, Fe, As, Cd, Pb, Cu, Zn and Hg) in various tissues (gills, hepatopancreas, muscle) of both dead and live crayfish in this locality compared to reference populations, these crayfish had experienced long-term exposure to increased levels of these metals. Here we give detailed documentation of crayfish mortality associated with high metal concentrations in the gills and other tissues of these endangered invertebrates.

Quality evaluation of frozen apheresis red blood cell storage with 21-day postthaw storage in additive solution 3 and saline-adenine-glucose-mannitol: biochemical and chromium-51 recovery measures.

BACKGROUND: The Czech Republic decided to build the frozen red blood cell (RBC) bank for military contingency and civil emergency preparedness. Storage methods were validated with (51)Cr recovery measures out to 21 days postthaw. STUDY DESIGN AND METHODS: A total of 139 apheresis RBC units collected in additive solution (additive solution 3 [AS-3] or saline-adenine-glucose-mannitol [SAG-M]) were obtained from volunteers by double erythrocytapheresis; all were sterilely glycerolized, frozen, stored for at least 30 days at a minimum of -65 degrees C in collection or cryogenic bags, thawed, sterilely deglycerolized, and stored at 4 +/- 2 degrees C for up to 21 days in AS-3 or SAG-M. Units were sampled before storage and after thaw weekly. Metabolic intermediates and (51)Cr recovery measures were obtained to determine the index of therapeutic effectiveness (ITE). RESULTS: Despite losses associated with cryoconservation and eventual transfer to cryogenic bags, 3-week storage with optimum ITE was obtained with frozen storage in primary collection or cryogenic bags and postthaw storage in AS-3. Such cells would pass as acceptable in vitro hematology and biochemistry variables. CONCLUSIONS: A system for frozen RBC storage with 3-week, postthaw, liquid storage has been validated. With commercially available components and automated processing, it is capable of supporting civilian rare blood and emergency and international military combat and peacekeeping support use patterns.

Improvement in Semen Conservation of the Indigenous Czech Endangered Old Kladruber Horse: Special Focus on the Type of Extender and Packaging System.

The aim of our study was to investigate the effect of two freezing extenders and two packaging systems on motility, plasma membrane (PM) integrity, and the apoptotic status of frozen-thawed (F-T) spermatozoa of the endangered Old Kladruber stallions. The collected semen (n = 6 stallions, three collections each) was diluted either with Gent or Lactose-EDTA (Lact) extender. Two aliquots of semen from each collection diluted in this way were prepared and then loaded into 5-mL aluminum tubes or 0.5-mL plastic straws. After thawing and then at 15 minutes intervals within 1 hour, the samples were analyzed for motility (CASA), PM integrity (CFDA/PI), and apoptotic changes of the spermatozoa (Yo-Pro-1/PI). Using Gent, the samples exhibited higher motility, kinematic parameters, higher representation of spermatozoa in medium, and fast subpopulation, as well as more spermatozoa with intact PMs and fewer spermatozoa with apoptotic changes compared with Lact extender (P < .05). Progressive motility and PM integrity was superior when using Gent and 5-mL aluminum tubes as compared with the rest of the combinations (P < .05). Kinematic parameters, percentage of spermatozoa in fast subpopulation and apoptotic status was superior in Gent and 0.5-mL straws as compared with the rest of the combinations (P < .05). Moreover, we revealed that F-T semen reacts diametrically differently when two different extenders and packaging systems are used. The study concludes that the combination of Gent and 0.5-mL straws represent adequate freezing system to maintain the appropriate quality of spermatozoa of this endangered breed.

Vitamin D status among the juvenile population: A retrospective study.

Vitamin D deficiency is a clinical problem and recently we have shown that 82.5% of our entire study cohort had inadequate serum 25(OH)D levels. In this study, we analysed serum 25(OH)D levels of juvenile patients admitted to the Burjeel Hospital of VPS Health care in Abu Dhabi, United Arab Emirates (UAE) from October 2012 to September 2014. Out of a total of 7883 juvenile patients considered in this study, almost 58.1% of females and 43.3% of males in the age group of 1-18 years were found to have low serum 25(OH)D levels (<50nmol/L). According to the coefficient of variation, females had significantly higher variability among juveniles (63.8%) than males (49.9%). Among the juveniles group of patients, age appears to be an important determining factor for defining vitamin D deficiency.The risk of deficiency (<30nmol/L) was found to be present in 31.4% of patients in the age group of 10-12 years, followed by 50.4% of patients in the age group of 13-15 years and 52.9% of patients in the age group of 16-18 years. The analysed age groups of females were found to have lower levels of 25(OH)D than males. It is important and perhaps alarming to note that such high rate of vitamin D deficiency is present in the juvenile age.

Vitamin D deficiency: A single centre analysis of patients from 136 countries.

Vitamin D deficiency is a global problem, thought to be related to lack of sunlight exposure, and usually accompanied by reduced dietary intake. This study was designed to determine vitamin D status of 60,979 patients admitted to the Burjeel Hospital of VPS healthcare in Abu Dhabi, United Arab Emirates (UAE) from October 2012 to September 2014. The total concentrations of vitamin D [25(OH)D] of all the studied patients were measured in a single laboratory. Of the studied patients, 57.5% were female and 42.5% were male. Serum 25(OH)D (total) measurements showed 82.5% of the studied patients have vitamin D deficiency to insufficiency. 26.4% of females and 18.4% of males have extreme deficiency of 25(OH)D. There was higher variability of vitamin D in group of females then males according to coefficient of variation. In our studied cohort teenagers (13-19 years) have shown the lowest levels of serum vitamin D (data not shown and will be communicated as a separate publication). The prevalence of hypovitaminosis D is significantly high among population of UAE, Saudi Arabia and many Middle Eastern countries, especially among women, despite abundant sunshine. 86.1% UAE nationals and 78.9% visitors of other nationalities were found <75nmol/L of 25(OH)D. 28.4% of UAE nationals and 17.5% of visitors of other nationalities have extreme deficiency of 25(OH)D. Our results are significant, as all of our patients are residing permanently in the UAE or visitors that has yearlong sunlight. In addition, measuring 25(OH)D concentrations in a single laboratory minimized test level variations. Our current study formed the basis of further studies to determine if vitamin D deficiency and insufficiency can aggravate systemic diseases, including hypertension, diabetes or obesity that are also wide-spread in the Middle Eastern region.