Cottonseed Oilcake as a Protein Source in Feeds for Juvenile Tilapia (Oreochromis niloticus): Antinutritional Effects and Potential Detoxification by Iron Supplementation

MERİÇ TURGUT İ., Wuertz S., Kloas W., Wibbelt G., Schulz C.

ISRAELI JOURNAL OF AQUACULTURE-BAMIDGEH, cilt.63, 2011 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 63
  • Basım Tarihi: 2011
  • Dergi Adı: ISRAELI JOURNAL OF AQUACULTURE-BAMIDGEH
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: tilapia, cottonseed, iron, fishmeal, gossypol, cottonseed, growth, histology, sublethal, chronic, TROUT ONCORHYNCHUS-MYKISS, RAINBOW-TROUT, BODY-COMPOSITION, IMMUNE-RESPONSE, NILE TILAPIA, FED DIETS, GOSSYPOL, MEAL, GROWTH, PERFORMANCE
  • Ankara Üniversitesi Adresli: Evet

Özet

Crude cottonseed oilcake, a protein-rich by-product of cottonseed oil production, was used to replace fishmeal in diets for juvenile tilapia (Oreochromis niloticus). Crude cottonseed oilcake was included in the diets at levels of 0% (control), 15%, 30%, and 45%, as an alternative protein source. The impact of the main antinutritional component of cottonseed oilcake, gossypol, on growth and its chronic adverse effects on blood hematocrit and tissue histology were assessed and compared with the documented effects of cottonseed meal. The detoxifying effect of iron (Fe) on gossypol was evaluated in the diets containing 30% and 45% cottonseed oilcake, which were supplemented with ferrous sulfate heptahydrate. As the rate of oilcake rose, the specific growth rate and protein efficiency ratio slightly, but significantly, dropped. Ferrous supplementation compensated for this effect in the 30% diet, but not in the 45% diet. However, iron supplementation led to mild inflammation in the intestine (infiltration of neutrophilic granulocytes), fatty degeneration of the liver, and a lower hepatosomatic index. Nevertheless, due to the beneficial effect on growth, iron supplementation is critical. No histopathological effects of the dietary cottonseed oilcake were observed in the gills, gonads, or heart. In conclusion, the effects of cottonseed oilcake supplementation were moderate when compared to the effects of cottonseed meal and a replacement level of 15-30% is recommended to obtain non-detectable effects.