Twenty-one samples from the Cantabrian coast were analyzed to establish their microbiological quality and fermentation tendency. In a food with a very low free-water content like honey, microbiological growth is only possible when there is an increase in water activity. Since most of the samples studied were not extensively granulated, the risk of fermentation is mostly due to high water content. Among our samples, only two had a water content below 17.1% (no risk of fermentation), whereas the high water activity of the rest of the samples indicates the possibility of microbial growth. In fact, four of the samples analyzed showed a moisture content over the Spanish maximum legal limit, which means a high risk of fermentation. The absence of Enterobacteriaceae, coliforms, and Escherichia coli in our samples indicates an appropriate cleanliness during extractions and handling of honey. No Salmonella or Shigella were found. The relationship between water activity and mold and yeast counts found for the honeys analyzed allowed us to divide our samples in two groups: honeys with a high or a low risk of fermentation. Changes observed during storage of the samples confirmed this classification.
A typing method for Corynebacterium bovis based on pulsed-field gel electrophoresis (PFGE) is described and applied to type 162 strains isolated from mastitic milk from 57 Friesian dairy herds in northern Spain. Isolates were identified to the species level using the API-Coryne system and a polymerase chain reaction-restriction fragment length polymorphism of the 16S rDNA amplicon. Cultures in logarithmic phase were harvested, mixed with agarose, and treated with lisozyme and proteinase K to release intact genomic DNA that was digested with XbaI and submitted to PFGE. Seven different pulsotypes were identified; none of them were similar to that of the reference strain (ATCC 7715). The most frequent pulsotype was pattern I (51.9%) followed by pattern II (29.6%). The majority of the herds showed infection with one single pulsotype, but 12 herds yielded 2 pulsotypes, and one herd had 3 pulsotypes. No relationship was found between the geographical location of the herd and the pulsotype. This is the first description of a typing method for C. bovis; the technique might prove useful for epidemiological studies on this species.
The objective of this paper is to evaluate the microbiological state and the dynamics of the mammary infections of organic farms in North Spain to discover if the high somatic cell count (SCC) observed in these farms is associated to a high incidence of mastitis. Microbiological cultures and SCC were performed in 8,496 foremilk samples collected from 160 cows in five representative organic farms from February 2006 to January 2008. Even though 79.3% of cultures were positive, only 21.2% of the total fit our diagnosis of mastitis (clinical, subclinical and chronic). The great prevalence of Corynebacterium bovis (teat canal-region pathogen) in the positive cultures that did not fit the mastitis diagnosis criteria (nearly 70%) compared with those that did (27%) was found to be related to lack of post-milking teat disinfection. The study prevalence of mastitis was 69.2% (66.7% subclinical mastitis, 27.8% clinical mastitis); the mean monthly prevalence was 47.4%; the mean monthly incidence was 12.9% and the mean duration of infection was 3.84 ± 3.98 months The high SCC in foremilk samples from old cows (three or more lactations) not diagnosed as mastitis compared to the heifers, reflects a worsening health status of the animals over time. When compared with the conventional sector in Northern Spain, these parameters indicate a poorer udder health in the studied organic herds with a high presence of chronic subclinical processes.
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