Occurrence and pathology of Sinergasilus lieni (Copepoda: Ergasilidae), a parasite of the silver carp and bighead, in Hungarian ponds

Sinergasilus lieni Yin, 1949, a well-known and pathogenic parasitic cope-pod in China and Russia, has been detected in Hungarian carp farms for the first time. The parasite infected the third-year generation of silver carp (Hypophthal-michthys molitrix) and bighead (Aristichthys nobilis). The gills of the infected fish specimens showed severe pathological changes. At the attachment sites of female copepods clubbing and fusing of the gill filaments were observed and in some parts of the pale or whitish hemibranchia deep indentations were recorded in places where the tips of the damaged filaments had broken off. Silver carp and bighead were infected at a similar rate, having 8 to 27 copepods attached to the end of the clubbed filaments or the proliferated epithelium of 2 to 10 fused filaments. In histological sections the head part of the parasite was found in a deep cavity of the proliferated epithelium, piercing its antennae deep into the tissues. Only the end of the filaments showed changes. In this part the proliferated epithelium was infiltrated by eosinophilic granular cells. In the central and basal parts of the hemibranchia the original structure of the filaments was preserved with intact secondary lamellae

TIMSS in a Western European Context

This special issue focuses on national findings and analyses from five Western European countries that participated in the Third International Mathematics and Science Study (TIMSS). TIMSS is an international, com-parative study designed to provide policy makers, educators, researchers, and practitioners with information about mathematics and science achieve-ment and its learning contexts in order to enhance mathematics and science learning within and across systems of education. TIMSS is conducted under the auspices of the International Association for the Eval-uation of Educational Achievement (IEA). It is co-ordinated by the Inter-national Study Centre at Boston College in the United States. More than 40 educational systems participate in TIMSS. It is the most complex IEA study to date and the largest international comparative study on education-al achievement ever undertaken. The study focuses on three populations o