Studies on the natural food of different fish species in intensively manured polyculture ponds

Relationship between gill raker morphology and feeding habits of hybrid bigheaded carps (Hypophthalmichthysspp.)

“…The linkage between the proportion of different planktonic size classes in the water and in the diet of fish was detectable in case of both phytoplankton and zooplankton, being more typical for the latter. Previous studies reported that silver carps can filter and consume smaller particles than bighead carp (Cremer and Smitherman, 1980;Spataru et al, 1983;Shapiro, 1985;Kolar et al, 2007), while others pointed out that silver carp are able to collect algae larger than 10 µm (Hampl et al, 1983;Smith, 1989;Vörös et al, 1997). However, similarly to Cremer and Smitherman (1980) or Xie (1999), we have also found that a smaller but still considerable fraction of the algae in the food of bigheaded carps was smaller than 10 µm, suggesting that these fish are able to filter and consume even nanoplankton.…”

Gut contents of silver carp, Hypophthalmichthys molitrix, and the disruption of a centric diatom, Cyclotella, on passage through the esophagus and intestine

“…and 34-41 mm when the fish length was 34-47 cm. Spataru et al 1983 found that Ž . DGR of silver carp was 36 33.9-37.2 mm when the body length of the fish was ca.…”

Phytoplankton, especially diatoms, in the gut contents and feces of two plantivorous cyprinids—Silver carp and bighead carp

“…Liu (1981) reported that DGR of silver carp was 15-25 am when the fish length was 1.5-10 cm, and 34-41 ~m when the fish length was 34-47 clrg and that of bighead was 30-35 lan when the fish length was 1.5-3 cm, and 30-72 lan when the ftsh length was larger than 3.5 cm. Spataru et al (1983) found that DGR of silver carp was 36 (33.9-37.2) and that of bighead carp was 84(83.9"86.8) #m when body lengths of the fishes were ca. 15-30 ClIL These observations indicate that the distance between gill rakers of silver carp is larger than 15 /ml and that of bighead is larger than 30 #rn.…”

“…The diameter of Cydotella is usually smaller than 20 /ma (the majority 6-15 /an), while the length of Cryptomonas is usually smaller than 30 fan (the majority 10-20 grn). However, the distances between gill rakers of silver carp are larger than 15 /an and those of bighead larger than 30 grn (Liu, 1981;Hampl et al, 1983;Spataru et al, 1983). If the carps can only use the food particles larger than the distances between their gill rakers, Cydotella almost cannot be used by both carps,, and Cryptomonas would only be partly used by silver carp.…”