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Sensitivity to anesthetic clove oil different species of adult fish
ŠKEŘÍK, Jindřich
Nomenclature: Sensitivity to anesthetic clove oil different species of adult fish Sensitivity of breeding fishes of various species (Siberian sturgeon, Brook trout, Black carp- young breeding fishes) for anesthetic clove oil was probed by the tests performed at temperature in the period of stripping (apart from Brook trout and Black carp). The tests were carried out with 17 fish species- with cyprinids (Ide- golden form, Common dace, European Chub, Sneep, Barbel, Grass carp, Black carp, bighead carp), salmonids (Brown trout, Rainbow trout, Brook trout), thymallinae (Grayling), pikes (Northern pike), perches (Pike-perch), sturgeons (Siberian sturgeon, Beluga) and airbreathing catfishes (North African catfish). Using concentration of 0,03ml.l-1 (Brown trout, Rainbow trout, Brook trout, Grayling, Pike, Pike perch, Ide, Dace, Chub, Barbel and Sneep), 0,04ml.l-1 (Grass carp, Black carp, Bighead carp), 0,05ml.l-1 (North African catfish) and 0,07ml.l-1 (Siberian sturgeon, Beluga) the IIb. Phase has been achieved, which is sufficient for manipulation with fishes during stripping. The anesthesia subsided after time period of 10-17 minutes (12 species) at the majority of fishes and at others after interval of 20-26 minutes (5 species). The results confirmed concentrations recommended for salmodis and Grayling (0,025-0,03ml.l-1), sturgeons (0,07ml.l-1), and North African catfish (0,05ml.l-1). At the majority of cyprinids (apart from Grass carp, Black carp and Bighead carp), the concentration used was lower than recommended (0,04-0,05ml.l-1)
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Occurrence and characteristics of ide (Leuciscus idus Linnaeus, 1758) catches in drainage area of the Morava River
Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan
The ide, Leuciscus idus belongs to autochthonous, less numerous and endangered (vulnerable) fish species of the Czech Republic. In 2004, the fishing on ide was conducted on 51 non-salmonid (NS) fishing-grounds of the Moravian Anglers Union (MAU) on water area of 4622.4 ha. In total, 432 ides (= 0.31 ind.ha-1; 0.25 % of all captured fish) and 332 kg of ide biomass (= 0.23 kg.ha-1, = 0.10 % of total mass of captured fish) were captured in 2004. Mean individual mass of ide was 0.78 kg. In the period 1990-2004, 0.11 ind.ha-1 (= 0.067 % of all captured fish) and 0.075 kg.ha-1 (= 0.035 % of total mass of captured fish) in the NS fish-grounds of MAU were captured yearly. During 1953-1978, 1.67 ind.ha-1 and 1.41 kg.ha-1 of the ide were captured yearly in the riverine fishing-ground Dyje 7. General trend of catches is decreasing. Legislative species protection, artificial reproduction and restocking of fish fry and 1+ juveniles were realized.
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Early development of ide (Leuciscus idus): species determining parameters
Prokeš, Miroslav ; Peňáz, Milan ; Baruš, Vlastimil ; Hamáčková, J. ; Lepič, P. ; Kozák, P. ; Policar, T.
Main species determinant characters of dace (Leuciscus idus) in the early ontogeny were described and compared with analogical parameters referred in literature with chub (Leuciscus cephalus) and dace (Leuciscus leuciscus). Dealt about of morphological and morphometrical characteristics of eggs, free embryos, larvae and juvenile individuals (egg diameters, embryo lengths at hatching, larvae lengths at the start of exogenous nutrition, juvenile individuals lengths at the time of scale formation, number of body and caudal segments, number of fin rays, number of scales, mouth and fin position, caudal fin laps depth, fin coloration, pigmentation and next characters). The ide is morphologically very similar with the chub and dace. Species determination during early ontogeny is difficult.
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