The study aimed to investigate some morphometric traits, length-weight relationship, meat yield, fecundity and some biochemical compositions of Astacus leptodactylus, in one of the Bafra Fish Lakes named Ulugöl, Samsun, Turkey. A total of 378 A. leptodactylus (198 female and 180 male) were examined. The average carapace length was 50.96±0.46 mm for females, 51.31±0.66 mm for males and 51.13±0.40 mm for all sampled crayfish. Abdomen length was 52.36±0.49 mm for females, 49.26±0.62 mm for males and 50.87±0.40 mm for all sampled crayfish. Live weight was between 14.38 g and 105.03 g with an average of 38.26±0.73 g. The average weight of females was less than that of males. There was a strong relationship between length and weight. The weight of crayfish with pleopodal eggs ranged from 28.24 g, to 59.50 g with an average of 41.73±1.09g. The average number of eggs per individuals was 192.90±9.94 with an average number of 4.62±0.21 per unit of live weight. The average total egg weight was 3.35±0.19 g while the average egg diameter was 2.17±0.03 mm. Abdomen meat was lower for males comparing with females. Average moisture, crude ash, crude oil and crude protein of abdomen meat were 81.27%, 1.47%, 0.81% and 16.45%, respectively.

In this study, it was aimed to determine there and fecundity by adapting crayfish (Astacus leptodactylus) obtained from Bafra Fish Lakes (Ulugöl-Samsun) in culture conditions. Crayfish obtained in November 2016 were stocked in tanks and egg and morphometric characteristics of female crayfish with carrying eggs were determined. Correlation analysis were used for the relationship between the determined parameters. The mean total weight and total length of crayfish were 41.79±3.00g, 10.72±0.22cm, respectively whereas the mean number and diameter of eggs were 156.40±33.24 and 2.50±0.12mm. There were positive strong relationship between total length and total weight of crayfish negative relationship was found between egg diameter and total number of eggs, egg diameter and total weight of eggs and egg diameter and number of eggs for per unit of live weight.

Bu çalışmada kerevit (Astacus leptodactylus Eschscholtz) yemine farklı oranlarda katılan selenyumun hepatopankreas ve gonad dokularında paraoksonaz (PON) ve arilesteraz (ARE) enzim aktivitelerine etkisi araştırılmıştır. Çalışmada, toplam selenyum düzeyi 0,3, 0,6, 0,9 ve 1,2 mg/kg yem olan sırasıyla; Kontrol (K), Deneme 1 (D1), Deneme 2 (D2) ve Deneme 3 (D3) yemleri oluşturulmuştur. Araştırma yemlerinin ham protein ve toplam enerji düzeyleri eşitlenmiştir. Çalışmada ebatları 2,0 × 2,0 × 1,0 m olan 12 adet havuz kullanılmıştır. Her bir havuza 75 dişi-25 erkek olacak şekilde toplam 1200 adet kerevit stoklanmıştır. Üç tekrarlı olarak yürütülen çalışmada kerevitler günde 2 öğün olmak üzere 9 ay süreyle yemlenmiştir. Kerevitlerden aylık olarak alınan doku örneklerinde PON ve ARE enzim aktiviteleri tespit edilmiştir. Deneme süresince hepatopankreas ve gonad dokularındaki PON ve ARE enzim aktivitelerinde istatistiksel olarak önemli farklılıklar bulunmuştur. Kerevitlerin dokularında üreme sezonu ve kuluçka süresi boyunca PON ve ARE enzim aktivitelerinin arttığı belirlenmiştir. Bu artışın kontrol grubuna kıyasla D1, D2 ve D3 gruplarında istatistiksel olarak farklı olduğu bulunmuştur. Sonuç olarak, selenyumun A. leptodactylus’un çiftleşme dönemi, yumurtlama dönemi ve kuluçka süresi boyunca PON ve ARE enzim aktivitelerini olumlu yönde etkilediği görülmüştür.