Occurrence and characterization of methicillin-resistant staphylococci from bovine mastitis milk samples in Finland

Background

Methicillin-resistant staphylococci (MRS) are increasingly being isolated in bovine mastitis. The aim of our study was to evaluate the occurrence of MRS in Finnish mastitis milk samples and characterize the MRS isolates using molecular methods.

Results

Methicillin-resistant S. aureus (MRSA) was a rare finding in bovine mastitis in Finland. Only two out of 135 (1.5%) S. aureus isolates were positive for mec genes. One of these carried mecA and was of spa type t172, SCCmec type IV and ST375, and the other harboured mecC, being spa type t3256, and ST130. MRSA ST375 is common among human MRSA isolates in Finland, but this is the first report in the country of bovine mecC MRSA. In coagulase-negative staphylococci (CoNS) originating from bovine mastitis, methicillin resistance was more common. In the two CoNS collections studied, 5.2% (17/324) and 1.8% (2/110) of the isolates were mecA positive. Eighteen of these were methicillin-resistant S. epidermidis (MRSE), which were divided into 6 separate PFGE clusters. One pulsotype was detected in different parts of the country, indicating clonal spread. Most MRSE (13/18) were of SCCmec type IV, one was of type V and four were non-typeable. Comparison with a human staphylococcal database indicated that bovine MRSE strains were not closely related to human MRSE isolates.

Conclusions

The occurrence of MRS, especially MRSA, in bovine mastitis in Finland was low. Most methicillin-resistant bovine CoNS are MRSE, and we found evidence of a bovine MRSE strain that may spread clonally. This is the first report of a Finnish bovine isolate of MRSA_mecC ST130. The study provides a baseline for further MRS monitoring.     

Overwintering,chemical variation,and genetic diversity in three vegetatively propagated lines of French tarragon (Artemisia dracunculus var. sativa)

Summary

French tarragon (Artemisia dracunculus var. sativa) has been vegetatively propagated for centuries, but variability in the vegetative lines has not been studied. Three lines of French tarragon (A – C) were studied for their overwintering capacity at the limit of survival, their essential oil content and composition, and their genetic variability. Line B had the lowest Winter survival rate, the highest biomass yield, and the lowest content of essential oils. The essential oils of line B had higher proportions of cis- and trans-ocimenes, and contained less estragole and herniarin than the essential oils of lines A and C. When genetic diversity was studied using restriction fragment length polymorphism (RFLP), all French tarragon lines clustered together, while Russian tarragon was monophyletic. Lines A and B were genetically closer to each other than line C. These results indicate that all three lines tested were genetically and biochemically different, which may have resulted from spontaneous mutations over centuries of vegetative propagation. Our results demonstrate the need to monitor and preserve the most important traits for future cultivation and use of vegetatively propagated herbs.     

Polypore diversity in the herb-rich woodland key habitats of Koli National Park in eastern Finland

Species diversity of polypores (Basidiomycetes) was compared between woodland key habitats (WKHs) and old-growth forest controls in boreal forests in eastern Finland. WKHs, which were set aside for their rich vascular plant flora, turned out not to be hot spots for the species richness of polypores, nor did their species composition represent the overall species richness of the area. Differences in the total volume of CWD, tree species composition and several CWD qualities were reflected as differences in the species assemblages between the groups. The results indicated that only a fraction of the overall polypore diversity was represented in the small-size WKHs (<0.5 ha), and the protection of red-listed and indicator polypores in WKHs was random. However, rare old-growth forest indicators were found even in small-size WKHs, if the CWD quality was appropriate for them. Nevertheless, our study does not answer the question whether the occurrences of rare and red-listed species will survive in small-size WKHs surrounded by altered environments such as clear-cuts, because our study sites were located in undisturbed areas. The results stress the importance to protect typical old-growth forest patches with high CWD volume and quality in boreal forests.     

Malignant catarrhal fever in pigs and a genetic comparison of porcine and ruminant virus isolates in Finland

An outbreak of the sheep-associated form of malignant catarrhal fever (MCF) in a Finnish sow herd was diagnosed by histopathology and confirmed by PCR. Several gilts and sows were suffering from high fever and anorexia and had aborted, and six of them had died. Typical signs of lymphoproliferation and vasculitis were observed histologically in several tissues, including the uterus. Ovine herpesvirus-2 (OvHV-2) was detected by PCR in two sows. Sequences of the OvHV-2 tegument protein gene obtained from the sows and from three cases of sheep-associated mcf in Finnish cattle were compared and found to be identical. These are the first confirmed cases of mcf in pigs in Finland.     

Structural requirements for repellency: norsesquiterpenes and sesquiterpenoid derivatives of nootkatone against the Formosan subterranean termite (Isoptera: Rhinotermitidae)

BACKGROUND: Research has shown that the family of grapefruit flavors called nootkatones have significant repellant and toxic effects to Formosan subterranean termites (Coptotermes formosanus Shiraki). RESULTS: Nineteen synthetic nootkatone derivatives, along with three commercially available nootkatone derivatives, were tested for repellent activity against C. formosanus by a choice assay in a petri dish with a two‐step triage procedure. Based on the repellency threshold value, the relationships between structure and activity are discussed. CONCLUSION: Four derivatives of nootkatone have very high repellency and toxicity to C. formosanus, 9 times the potency of the primary compound nootkatone. Four other compounds have between 2 and 3 times the repellency of nootkatones, and three compounds are equal in their repellency to nootkatone. Copyright © 2010 Society of Chemical Industry     

Eicosapentaenoic and Arachidonic Acids from Phytophthora infestans Elicit Fungitoxic Sesquiterpenes in the Potato

Mycelial extracts from Phytophthora infestans caused necrosis and elicited the accumulation of antimicrobial stress metabolites in potato tubers. A portion of the material with elicitor activity could be extracted from the mycelium by a mixture of chloroform and methanol. The most active elicitors of stress metabolites in these extracts were eicosapentaenoic and arachidonic acids. These fatty acids were found in either free or esterified form in all active fractions of the mycelial extracts.     

Effect of heat treatment of dietary fiber: interlaboratory study

The effects of thermal treatments on the dietary fiber composition of cereal and potato samples were studied at 8 laboratories using different analytical methods. Thermal treatments included extrusion cooking for cereals, and boiling and frying for potatoes. No changes in the amounts of dietary fiber or starch were observed in the extruded samples. Heat-treated potato samples contained significantly more water-insoluble dietary fiber (cellulose) and less starch than did raw potato. However, this may be due, at least in part, to the sample preparation procedure rather than the heat treatment alone. The study indicates that gravimetric and sequential hydrolysis methods give similar results, but the variation in most cases is still wide. Further standardization of methods is evidently needed, especially if legislative measures for setting limits on the fiber content of foods are to be introduced. Standardization of starch analysis should also be of primary importance in future work on carbohydrate methodology. This can be concluded from the variation in results concerning this extremely important food constituent. It should be noted that the sample matrix in the present study was simpler than that of complex meals or diets.     

Pea–oat intercrops to sustain lodging resistance and yield formation in northern European conditions

Abstract

Locally produced crop protein is urgently needed in Europe. Pea is a good protein source and is well adapted to northern conditions. Pea can fix nitrogen that the following crop in rotation can benefit from. In cereal-dominated cropping systems pea is a break crop disrupting the life cycle of cereal diseases, leading to less fungicide application and thereby minimizing off farm inputs and benefiting the environment. Grain legumes provide animals with protein and energy, and the seeds of pulse crops are complementary to those of cereals. Field peas can be cultivated in most parts of Scandinavia and interest in peas has increased for inclusion in organic farming. Growing pea as a sole crop is a challenge since its stem is prone to lodging thereby resulting in harvesting difficulties, reduced yield and decreased profits. Intercropping of pea with oat could minimize the above listed problems but to our knowledge proportion of seeds mixture of the two crops and selection of pea cultivars without compromising the pea yield, especially protein production, at high latitudes conditions is limited. Therefore, our objective was to evaluate performance of sole cropped pea (Karita, Perttu, Hulda) and oat (seed proportions 7.5% and 15%) and their intercrop combinations and establish an appropriate seed mixture for a pea–oat intercropping systems that prevents lodging without markedly reducing pea yield. Field experiments were conducted at three locations (Jokioinen, Mietoinen, Ylistaro) of the Agrifood Research Finland in 2002–2004. Intercropping peas with oats prevented peas from lodging and made their harvest easier. Optimal numbers of oats in pea intercrops were difficult to determine, varying according to pea cultivar and local growth conditions. Excess oats in the seed mixture or conditions favouring oat growth prevented peas from lodging but pea yield was decreased.