Avrupa Istakozu (Hommarus gammarus) Larvalarının Düşük Yoğunluk Koşulları Altında Pseudo-Yeşil Su ve Temiz Suda Büyümesi ve Hayatta Kalması

Öz

Avrupa ıstakozu, Homarus gammarus, Avrupa’da önemli bir ticari türdür. Son yirmi yıldır devam eden başarılı stok geliştirme çalışmalarına karşın, H. gammarus’un yetiştiricilik yöntemleri hala gelişmektedir.Bu çalışmada, düşük yoğunluklu stoklama şartlarında, konsantre alg içeren pseudo-yeşil su ve temiz su tekniklerinin H. gammarus larvalarının I-IV evreler arasındaki büyüme ve hayatta kalma oranları araştırılmıştır. Tüm larvalar 800 L hacmindeki silindir-konik tanklarda 1.25 larva/L stoklama yoğunluğunda 17.1±1 oC sıcaklık ve 32±1 ppt tuzlulukta yetiştirilmiştir. Istakoz larvaları zenginleştirilmiş Artemia ile 3-5 naupli/ml oranında 10 saat süre (09:30 - 19:30) ile beslenmiştir. Tanklara günlük eklenen konsantre alg, eklenmeyen temiz su şartlarına göre türbiditeyi arttırmış ve görüş mesafesini azaltmıştır. Sonuçlar, farklı gruplardaki ıstakoz larvalarının I-IV evrelerde büyüme ve hayatta kalma oranlarının istatistiksel olarak farklı olmadığını göstermiştir (p>0.05). Ortalama hayatta kalma oranı %3’tü ve gruplar arasında bir farklılık ortaya çıkmamıştır. Artan türbidite şartları ve düşük stoklama yoğunluğu hayatta kalma oranlarını arttırmamıştır. Istakoz larvalarının pelajik evrelerde daha yüksek hayatta kalma oranlarını sağlayacak çalışmaların yapılması gereklidir.

Anahtar Kelimeler

• Homarid istakoz
• Decapod
• Kanibalizm
• Larva yetiştiriciliği

The Growth and Survival of The European lobster (Hommarus gammarus) Larvae in Pseudo-Green Water and Clear Water Under Low Density Conditions

Öz

The European lobster, Hommarus gammarus, is a commercially important species in Europe. Despite successful stock enhancement programs during the last two decades, culture methods of H. gammarus are still in progress. In this study, the effects of pseudo-green water technique and clear water technique with lower stocking densities on the growth and survival of H. gammarus larvae during stages I-IV were investigated. All larvae were reared in 800 L cylindro-conical tanks with a stocking density of 1.25 larvae/L at a temperature of 17.1±1 oC and a salinity of 32±1 ppt. Lobster larvae were fed with enriched Artemia at a density of 3-5 naupli/ml for a period of 10 (09:30 am- 19:30 pm) hours. Daily additions of concentrated algae increased turbidity and reduced visibility in tanks compared to clear water conditions. Results showed that growth of lobster larvae were not significantly different among treatments during planktonic stages I-IV (p>0.05). Overall mean survival rate was only 3% with no significant differences between treatments. Increased turbidity and lower stocking density did not improve survival rates. Further studies are required to develop methods that will promote higher survival rates during the pelagic stages of lobster larvae.

Anahtar Kelimeler

• Homarid lobster
• decapoda
• cannibalism
• larval culture

Kaynakça

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