Potential of cottonseed oil as fish oil replacer in European Sea Bass feed formulation

Triplicate groups of 20 European sea bass (35 g) were fed five diets in which the added lipid was 100% fish oil (FO), 40% (CSO40), 60% (CSO60), 80% (CSO80) and 100% (CSO100) refined cottonseed oil (CSO), for a period of 120 days. Overall fish growth, feed conversion ratio and protein utilization were unaffected by dietary treatment, but hepatosomatic and visceral fat indexes increased with increasing dietary CSO. Fillet fatty acid composition of total lipids reflected the fatty acids in the test diets. The monounsaturated fatty acids were significantly higher in fillet of fish fed diet FO, CSO40 and CSO60 compared to other treatments while saturated and polyunsaturated fatty acids (PUFA) were not affected by the dietary treatment. Some fatty acids (18:0, 18:1n-9, 20:5n-3 and 22:6n-3) were present in higher concentration in fillet lipid than in the CSO100 dietary lipid indicating accumulation in fillet relative to test diets. Retention of n-3 LC-PUFA within the fillet was increasingly inefficient among fish fed increasing levels of FO. Thus, this study suggests that CSO can be considered as a relatively effective substitute for fish oil in European sea bass (35 g) in terms of growth performances and feed efficiency as far as fish meal is present in the diet

From the sea to aquafeed: A perspective overview

Aquaculture has been one of the fastest-growing food production systems sectors for over three decades. With its growth, the demand for alternative, cheaper and high-quality feed ingredients is also increasing. Innovation investments on providing new functional feed alternatives have yielded several viable alternative raw materials. Considering all the current feed ingredients, their circular adaption in the aquafeed manufacturing industry is clearly of the utmost importance to achieve sustainable aquaculture in the near future. The use of terrestrial plant materials and animal by-products predominantly used in aquafeed ingredients puts a heavily reliance on terrestrial agroecosystems, which also has its own sustainability concerns. Therefore, the aquafeed industry needs to progress with functional and sustainable alternative raw materials for feed that must be more resilient and consistent, considering a circular perspective. In this review, we assess the current trends in using various marine organisms, ranging from microorganisms (including fungi, thraustochytrids, microalgae and bacteria) to macroalgae and macroinvertebrates as viable biological feed resources. This review focuses on the trend of circular use of resources and the development of new value chains. In this, we present a perspective of promoting novel circular economy value chains that promote the re-use of biological resources as valuable feed ingredients. Thus, we highlight some potentially important marine-derived resources that deserve further investigations for improving or addressing circular aquaculture

Deniz levreğinin (Dicentrarchus labrax) tatlısuda semirtilme olanağı

TEZ3230Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 1999.Kaynakça (s. 51-58) var.vi, 58 s. ; 30 cm.

Deniz levreği (Dicentrarchus labrax)'nin alıştırılması ve tatlısuda optimal yemleme oranının belirlenmesi

TEZ4521Tez (Doktora) -- Çukurova Üniversitesi, Adana, 2003.Kaynakça (s. 97-111) var.vıı, 111 s. ; 30 cm.…Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi Tarafından Desteklenmiştir. Proje No:FBE.2002.D.6

Sıcaklık ve substratın Penaeus semisulcatus (Decapoda: Penaeidae) postlarvalarının büyüme ve yaşama oranı üzerine etkisi

Bu çalışma, iki ayrı deneme halinde, Penaeus semisulcatus’un ön-semirtme dönemindeki optimum su sıcaklığının belirlenmesi ve substratın büyüme ve yaşama oranı üzerindeki etkisini belirlemek amacıyla yapılmıştır. Altı hafta sonunda, 22, 24, 26, 30 ve 34°C’de elde edilen yaşama oranları sırasıyla %52, 46, 70, 30 ve 40 olarak bulunmuştur. Total boyca en yüksek (2,76 mm/hafta) ve en düşük (0,43-0,49 mm/hafta) büyüme oranları 34°C ve 22-24°C’de yetiştirilen postlarvalarda (PL) bulunmuştur. 26°C ve 30°C’lerdeki haftalık büyüme oranları sırasıyla 1,03 mm ve 1,75 mm’dir. Sıcaklığın 22°C’den 34°C’ye çıkmasıyla deneme sonu bireysel ağırlık 55 mg’dan 285 mg’a çıkmıştır (yaklaşık 5 kat artış). 22, 24 ve 26°C’de yetiştirilen PL’lerde büyüme farklı bulunmamıştır (P>0.05). Ağırlıkça büyüme oranı 34°C’de 432 mg/hafta ve 22-24°C’de 58-68 mg/hafta olarak belirlenmiştir. 34°C’de büyütülen PL’ler 22-24°C’dekilere göre 6-7 kat daha hızlı büyümüşlerdir. 34°C’de elde edilen ürün (5,7 g), 22°C’dekinden (1,43 g) 4 kat daha yüksek çıkmıştır. 24, 26 ve 30°C’de elde edilen ürün miktarları, sırasıyla 1,40, 3,03 ve 2,59 g’dır. Yaşam alanını arttırmak için ağdan yapılmış yapay substrat kullanımı yaşama ve büyüme oranlarını olumlu yönde etkilememiştir.This study was carried out to determine the optimal water temperature and to investigate the effects of additional substrate on growth and survival during the nursery culturing of Penaeus semisulcatus in two separate experiments. At the end of six weeks, survivals of postlarvae (PLs) at 22, 24, 26, 30 and 34$circ$C were 52, 46, 70, 30 and 40%, respectively. The highest (2.76 mm/week) and lowest growth rates in terms of total length (0.43-0.49 mm/week) were displayed by the PLs grown at 34$circ$C and 22-24$circ$C, respectively. Growth rates were 1.75 mm/week at 30¡C and 1.03 mm/week at 26$circ$C. Final individual weight showed a drastic increase (over five times) with increasing temperature level from 22$circ$C (55 mg) to 34$circ$C (285 mg). Individual final weights at 22, 24 and 26$circ$C were not significantly different from each other (P>0.05). Weight gain per week was 432 mg/week at 34$circ$C and 58-68 mg/week at 22-24$circ$C. The PLs at 34$circ$C had a growth rate 6-7 times faster than those at 22-24$circ$C. Yield at 34$circ$C (5.7 g) was four times as high as that at 22$circ$C (1.43 g). The yield at 24, 26 and 30$circ$C was 1.40, 3.03 and 2.59 g, respectively. Artificial substrate constructed of seine netting to increase habitat area did not improve the survival and growth of postlarvae compared with the control

Değişik tuzluluklarda ve tatlı suda yetiştirilen deniz levreğinde (Dicentrarchus labrax) büyüme performansı, vücut özellikleri ve fileto kompozisyonu

The effects of various salinities and fresh water (FW) (0.4 ppt) on the growth performance, body traits and fillet composition of juvenile and young sea bass (Dicentrarchus labrax) in FW were investigated in two separate experiments in this study. In Experiment 1, following acclimation, sea bass juveniles (9.5 $\pm$ 0.5 g) were reared in 240-L fibreglass tanks (40 x 40 x 150 cm) for 90 days in five different treatments (FW, 10, 20, 30 and 40 ppt). The fish cultured in FW, 10 and 20 ppt grew better than those at 30 or 40 ppt (P 0.05). Yet, the dry weight of the fish grown in FW was significantly lower than those reared in saline waters (P 0.05). Fish growth rates were 0.72 g day-1 in SW and 0.81 g day-1 in FW. Salinity did not significantly affect the meat crude protein, lipid or ash content (P > 0.05). Food conversion efficiency (FCE) was slightly higher in SW (77%) than in FW (74%). The mean fillet weight of the fish reared in FW was 16% higher than for SW. Fillet yields in FW and SW were 52% and 50%, respectively. From the blood plasma ions, Na+ and Cl- were lower in the fish grown in FW as compared to SW (P 0.05). Yet, the dry weight of the fish grown in FW was significantly lower than those reared in saline waters (P 0.05). Fish growth rates were 0.72 g day-1 in SW and 0.81 g day-1 in FW. Salinity did not significantly affect the meat crude protein, lipid or ash content (P > 0.05). Food conversion efficiency (FCE) was slightly higher in SW (77%) than in FW (74%). The mean fillet weight of the fish reared in FW was 16% higher than for SW. Fillet yields in FW and SW were 52% and 50%, respectively. From the blood plasma ions, Na+ and Cl- were lower in the fish grown in FW as compared to SW (P < 0.05), but K+ level did not vary between the treatments

Balık Yağına İkame Eden İki Farklı Bitkisel Yağ Sınıfının Juvenil Avrupa Deniz Levreğinde (Dicentrarchus Labrax) Besinsel Sindirime Etkileri

Bu çalışmada, balık yağı (BY) ve iki farklı bitkisel yağ (tekli doymamış yağ asitlerince zengin kolza yağı, KY ve n-6 çoklu doymamış yağ asitlerince zengin pamuk tohumu yağı; PTY) içeren yemlere tabi tutulan Avrupa deniz levreğindeki çoklu doymamış yağ asidi (PUFA)/ yüksek doymamış yağ asidi (HUFA) oranı değerlendirilmiştir. 20 adet Avrupa deniz levreği, (?35 g) 130 gün boyunca %100 balık yağı (BY), %100 rafine edilmiş kolza yağı (KY) ve %100 rafine edilmiş pamuk tohumu yağı ilave edilmiş 3 yemle beslenmiştir. Final ağırlığı, ağırlık kazancı ve spesifik büyüme oranı karşılaştırıldığında BY ve KY yemi ile beslenen balıklar PTY yemi ile beslenenlere göre önemli düzeyde daha yüksek bulunmuştur. KY ile beslenen balıklarda final ağırlığı (87,3±3,1 g), BY(84,3±1,2 g) ve PTY (80,4±2,3; P<0,05) ile beslenenlere kıyasla önemli ölçüde daha yüksek bulunmuştur. Filetodaki eikosapentaenoik asit, (EPA) ve dokosahekzaenoik Asit (DHA) yoğunluğu, yemlerdeki MUFA ve n-6 PUFA seviyelerinin artmasıyla azalmıştır. Buna göre, PTY ile beslenen balıkların DHA miktarı %9,41 iken KY (%7,93) ile beslenen balıkların kaslarındaki DHA miktarı daha düşüktür. Tahmin edildiği üzere, diyetlerdeki bireysel yağ asitlerinin emilimi zincir uzunluğu ile azalmakta ve doymamışlık derecesiyle artmaktadır. Diyetlerdeki PUFA/HUFA oranının artmasıyla görünen total yağ sindirilebilirliği azalmaktadır.This study evaluated dietary polyunsaturated fatty acid (PUFA)/highly unsaturated fatty acid (HUFA) ratios in European sea bass subjected to feeds containing fish oil (FO) or two different vegetable oils (the monounsaturated fatty acid: MUFArich rapeseed oil, RO; and the n-6 PUFA-rich cottonseed oil, CSO). Triplicate groups of twenty fish (35±0.2 g) were fed three fish-based diets in which the added lipid was 100% fish oil (FO), 100% refined low-erucic-acid-rapeseed oil (RO), 100% cottonseed oil (CSO) for a period of 130 days. As a result of this study, final weight, weight gain and specific growth rate were significantly higher in fish fed FO and RO diet compared to fish fed CSO. Final weight in fish fed the RO diet were significantly higher (87.3±3.1 g) in comparison to fish fed the FO (84.3±1.2 g) and CSO diets (80.4±2.3, <0.05). The concentration of eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in flesh was significantly reduced with increasing levels of MUFA and n-6 PUFA in the diet. Accordingly, DHA value in fish fed the CSO diet was 9.41% whereas fish fed the RO diet had lower (7.93%) DHA content in the flesh. As expected, the absorption of individual dietary fatty acids decreased with chain length and increased with the degree of unsaturation. The apparent total lipid digestibility decreased with increasing the PUFA/HUFA ratio in the diet

The Effects Of Size Grading On Growth Performance Of Rainbow Trout (Oncorhynchus Mykiss) In Floating Cage Condition

Alabalık yetiştiriciliğinde büyük balıkların küçüklerden ayrılmasının ve dolayısı ile sınıflandırmanın kafes ortamında ne derece etkili olduğunun belirlenmesi amacıyla yapılan bu çalışmada iki farklı deneme grubu oluşturulmuş ve 75 günlük besleme dönemi sonunda besi performansları değerlendirilmiştir. Denemede boylanmış grubu (K) 72,14±3,48 g lık küçük balıklar oluştururken, diğer grubu (B+K); %80 küçük balıklar (71,04±1,10) ve %20 büyük balıklar (151,8±8,14) oluşturmuştur. Deneme sonunda (K) grubunun 203,52±16,20 g ortalama canlı ağırlığa ulaşırken (B+K) grubunun küçük bireyleri 185,13±21,77 g, büyük bireyleri ise 223,25±28,00 g ortalamaya ulaşmışlardır. Boylanmış gruptaki yem değerlendirme oranı (1,61±0,052) diğer gruptan (2,17±0,039) daha düşüktür (P<0,05). Elde edilen bu sonuçlara göre sadece küçük bireylerin olduğu aynı boydaki grubun bireylerinin daha iyi büyüdüğü ve yemden yararlanma oranlarının daha iyi olduğu ve dolayısı ile %20 oranında büyük balıkların varlığı alabalıklarda büyümeyi kötü yönde etkilediği sonucuna varılmıştır.In the study, the effects of size grading on growth of rainbow trout in cage condition was examined. Two different test groups were made and after 75 days of daily diets the fattening performance value was analyzed. In the research, the graded group (S) was formed with small fish (72.14±3.48 g) while the other group (L+S) was formed with 80 % of small fish (71.04±1.10 g) and 20% of large fish (151.8±8.14 g). At the end of the study, the average weight of K group was found as (203.52±16.20 g); on the other hand in the group (L+S) the average weight of small fish was determined as (185.13±21.77 g) and the large ones as (223.25±28.00 g). Also feed conversion ratio in group S (1.61±0.052) was found lower than the other group (2.17±0.039). As a result of the study it was found that small fish in the same graded group grew more and feed conversion rate were better. Therefore, the growth performance of trout has been affected adversely by 20 % of large fish in the group (L+S)

The effects of size grading on growth performance of rainbow trout (oncorhynchus mykiss) ın floating cage condition

Alabalık yetiştiriciliğinde büyük balıkların küçüklerden ayrılmasının ve dolayısı ile sınıflandırmanın kafes ortamında ne derece etkili olduğunun belirlenmesi amacıyla yapılan bu çalışmada iki farklı deneme grubu oluşturulmuş ve 75 günlük besleme dönemi sonunda besi performansları değerlendirilmiştir. Denemede boylanmış grubu (K) 72,14±3,48 g lık küçük balıklar oluştururken, diğer grubu (B+K); %80 küçük balıklar (71,04±1,10) ve %20 büyük balıklar (151,8±8,14) oluşturmuştur. Deneme sonunda (K) grubunun 203,52±16,20 g ortalama canlı ağırlığa ulaşırken (B+K) grubunun küçük bireyleri 185,13±21,77 g, büyük bireyleri ise 223,25±28,00 g ortalamaya ulaşmışlardır. Boylanmış gruptaki yem değerlendirme oranı (1,61±0,052) diğer gruptan (2,17±0,039) daha düşüktür (P<0,05). Elde edilen bu sonuçlara göre sadece küçük bireylerin olduğu aynı boydaki grubun bireylerinin daha iyi büyüdüğü ve yemden yararlanma oranlarının daha iyi olduğu ve dolayısı ile %20 oranında büyük balıkların varlığı alabalıklarda büyümeyi kötü yönde etkilediği sonucuna varılmıştır.In the study, the effects of size grading on growth of rainbow trout in cage condition was examined. Two different test groups were made and after 75 days of daily diets the fattening performance value was analyzed. In the research, the graded group (S) was formed with small fish (72.14±3.48 g) while the other group (L+S) was formed with 80 % of small fish (71.04±1.10 g) and 20% of large fish (151.8±8.14 g). At the end of the study, the average weight of K group was found as (203.52±16.20 g); on the other hand in the group (L+S) the average weight of small fish was determined as (185.13±21.77 g) and the large ones as (223.25±28.00 g). Also feed conversion ratio in group S (1.61±0.052) was found lower than the other group (2.17±0.039). As a result of the study it was found that small fish in the same graded group grew more and feed conversion rate were better. Therefore, the growth performance of trout has been affected adversely by 20 % of large fish in the group (L+S)