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Determination of the quality parameters of pike perch Sander lucioperca caught by gillnet, longline and harpoon in Turkey

The effects of the different catching methods (gillnet, longline, harpoon) on sensory, chemical (pH, total volatile base nitrogen, K-value) and microbiological (total viable count [TVC]) changes in pike perch Sander lucioperca stored in ice were investigated. The same soaking time was used for both gillnet and longline fishing. The catching method had considerable influence on the freshness quality of pike perch. The acceptable shelf life was 15 days for pike perch caught by gillnet, and 22 days for longline and harpoon. The initial concentrations of inosine monophosphate (2.4 μmol/g) in pike perch caught by gillnet were significantly lower (P<0.05) than longline (4.1 μmol/g). and especially by harpoon (16.7 μmol/g). However, the initial K-values for fish caught by harpoon were significantly (P<0.05) lower (24.36%) than fish caught by longline and gillnet (57.69%, 64.41%, respectively). The average K, Ki, G and H-values at rejection day in terms of sensory assessment were approximately 90, 98, 156 and 40%, respectively, for all catching methods during ice storage. However, TVC reached 7.0 log cfu/g after approximately 11 days of storage for fish caught by gillnet, 19 days for fish caught by longline and 8 days for fish caught by harpoon. The result of this study suggests that the best catching method for preserving the freshness of pike perch is longline, based on the data obtained from the sensory and microbiological analysis.

Two new Lessepsian species found in the north-eastern Levantine Basin: Broadbanded Cardinalfish (Apogon fasciatus (White, 1790)) and Indian Scad (Decapterus russelli (Rüppell, 1830)) (Osteichthyes)

Broadbanded Cardinalfish, Apogon fasciatus (White, 1790) On 21.12.2009, six specimens of Apogon fasciatus were collected in a transect along the eastern shores of Iskenderun Bay (36°17’N, 35°45’E – 36°21’N, 35°47’E) near the 50 m depth contour. The total lengths of the collected specimens varied between 48.26 and 89.12 mm. Mean Total Length (TL) was 77.99 mm (SD = 17.22 mm), mean Standard Length (SL) of TL was 81.39% (SD = 1.25%). The body of the specimens is oblong and compressed. The body colour is tan-whitish, with two dark brown stripes present on the head and body. The lower stripe extends mediolaterally along the body from the snout to the tip of the caudal fin. The upper stripe above the lateral line extends from the post-temporal bone to the region behind the posterior end of the second dorsal fin. There are reddish-orange spots on the distal edges of second dorsal, anal and pectoral fins, and a reddish colour pattern was observed on the pelvic fins. There are two and three large scales on the preopercle and opercle, respectively. The preopercle edge is serrated (Fig. 1.). The metric and meristic characters used for identification are as follows; D1: VII and D2: I+9, A: II+8, Pec: 15, Pel: I+5, lateral line pored scales: 25-26, body depth at dorsal fin origin of SL (BDD): 34.84±2.64 mm, head length of SL (HL): 39.10±2.77 mm, distance from snout to first dorsal fin of SL: 37.94±1.63 mm, distance from snout to anal fin of SL: 61.17±2.50 mm, maximum pectoral fin length of SL: 23.85±1.08 mm.

THE GROWTH PARAMETERS OF THE MEDITERRANEAN SHRIMP (PENAEUS KERATHURUS FORSKAL, 1775) IN THE ISKENDERUN BAY

İSKENDERUN KÖRFEZİ’NDE AKDENİZ KARİDESİ (PENAEUS KERATHURUS FORSKAL,1775)’NİN BÜYÜME PARAMETRELERİ ÖZ Bu çalışmada, İskenderun Körfezi’nde Kasım 2009-Aralık 2010 tarih aralığında aylık olarak dip trolü çekimlerinden elde edilen Akdeniz karidesi (Penaeus kerathurus)’nin büyüme parametreleri belirlenmiştir. İncelenen 120 örnek bireyden 41 adedi erkek ve 79 adedi dişi olup; erkek/dişi oranı yaklaşık 1/2 dir. Örneklerin total boyları 8.5-19.1cm, total ağırlıkları 4.4-58.41g değerleri arasında değişim göstermekte ve ortalama boy 13.97±2.19cm ile ağırlıkları 24.09±11.19g olarak belirlenmiştir. Boy-Ağırlık ilişkisi toplam eşeyde W=0.0108*TL (R=0.9042) olup; büyümede negatif allometrik büyüme özelliği gösterdiği saptanmıştır. Von Bertalanffy Büyüme sabitleri L∞=20.95cm, K=0.470yıl -1 ve t0=-0.5138yıl -1 olduğu belirlenmiştir. Toplam ölüm oranı (Z), doğal ölüm (M) ve balıkçılık ölüm oranı (F) ile stoktan yararlanma düzeyi (E) sırasıyla 2.45yıl, 1.09yıl, 1.36yıl ve 0.55yıl olarak saptanmıştır. Anahtar Kelimeler: Akdeniz Karidesi (Penaeus kerathurus), İskenderun Körfezi, Büyüme Parametreleri, Ölüm Oranları, Stoktan Yararlanma Oranı