Herd-level risk factors for Cryptosporidium infection in dairy-goat kids in western France.

We conducted a cross-sectional study of risk factors for herd-level kid positivity for Cryptosporidium parvum oocysts in dairy-goat farms (Deux-Sèvres, western France). From January to March 2003, faeces from a convenient sample of 879 5- to 30-day-old goat kids from 60 herds were examined microscopically after staining with carbol fuschin. Oocyst shedding was scored semi-quantitatively (0 to 4+) allowing us to obtain a cumulative score per herd. Standardized questionnaires with information about management practices were collected in each farm. We found positive kids in 32 of 60 herds (53.3%) and in 142 animals out of 879 (16.2%). We used logistic regression for two risk-factor model: (1) simple positive (case: herd score > or = 1+, at least one positive kid in the herd, versus control: herd score=0), (2) strongly positive (case: overall herd score > or = 3+ versus control: herd score <3+). Risk factors associated with simple positive herds were period of sampling compared to the peak of births (After versus Before, OR=4.2, 95% CI 1.2, 15.3) and practice of kid grouping by age or weight (Yes versus No, OR=4.4, 95% CI 1.0, 19.1). Risk factors associated with strongly positive herds were period of investigation (February/March versus January, OR=12.7, 95% CI 2.1, 76.6), exposure to graminaceous plants in forage (OR=11.6, 95% CI 1.7, 81.0) and type of ventilation in the goat premises (Vertical versus Wind effect, OR=14.7, 95% CI 2.1, 106.1). No important association was found between kid-management practices and herd positivity. These results suggest a major role of the environment of kids during their first hours of life in the adult-goat premises regarding the transmission of C. parvum infection.

Main structural and stereochemical aspects of the antiherpetic activity of nonahydroxyterphenoyl-containing C-glycosidic ellagitannins.

Antiherpetic evaluation of five nonahydroxyterphenoyl-containing C-glycosidic ellagitannins, castalagin (1), vescalagin (2), grandinin (3), roburin B (5), and roburin D (7), was performed in cultured cells against four HSV-1 and HSV-2 strains, two of which were resistant to Acyclovir. All five ellagitannins displayed significant anti-HSV activities against the Acyclovir-resistant mutants, but the monomeric structures 1-3 were more active than the dimers 5 and 7. Vescalagin (2) stands out among the five congeners tested as the most potent and selective inhibitor, with an IC50 value in the subfemtomolar range and a selectivity index 5x10(5) times higher than that of Acyclovir. Molecular modeling was used to provide a rationale for the surprisingly lower activity profile of its epimer castalagin (1). These ellagitannins have promising potential as novel inhibitors in the search for non-nucleoside drugs active against Acyclovir-resistant herpes viruses.