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

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)

Thermal Tolerance of Turkish Crayfish (Astacus leptodactylus) Acclimated to Three Different Temperatures

Critical thermal maxima (CTMax) and minima (CTMin) were determined for Turkish crayfish (Astacus leptodactylus) acclimated to 15, 20 and 25°C. CTMin and CTMax were 1.3, 1.1 and 2.0°C, and 37.4, 37.5 and 38.7°C, respectively. Thermal tolerance tests showed that acclimation temperatures (15, 20 and 25C) had significant effects on CTMin values of A. leptodactylus (P≤0.05). The area of thermal tolerance assessed using the CTMin and CTMax boundaries were calculated as 364°C2. The overall ARR values were calculated as 0.07 for CTMin and 0.13 for CTMax values between 15 and 25 C acclimation tempera-tures. All the crayfish crumpled at 0.5°C and showed overall spasm at 32.0 – 33.0°C. Farming A. leptodactylus in the southeastern part of the Mediterranean region may be practiced in terms of temperature tolerance

Diyetlerde kullanılan pamuk tohumu ve kanola yağlarının jüvenil gökkuşağı alabalıklarında (oncorhynchus mykiss) büyüme performansı, yağ asidi kompozisyonu ve organ histolojisine etkileri

Bu araştırmada, diyetlerde balık yağı yerine %50 oranında kullanılan pamuk tohumu yağı (PTY) ve kanola yağı (KY) ya da bu yağların eşit karışımlarının jüvenil gökkuşağı alabalığının büyümesine, yağ asidi kompozisyonuna ve sindirim sistemi histolojisine etkileri araştırılmıştır. Araştırmada, farklı 5 adet izonitrojenik ve izolipidik diyetler hazırlandı. Kontrol diyetinde sadece balık yağı (BY) ve hazırlanan diğer diyetlerde sırasıyla sadece PTY, sadece KY, %50 PTY/%50 KY ve %50 BY/%50 belirtilen bitkisel yağların eşit karışımı kullanılmıştır. Deneyde ortalama ağırlıkları yaklaşık olarak 15 g olan gökkuşağı alabalığı yavruları kullanılmıştır. Deney paralelli ve her deney tankında 50 adet balık olacak şekilde 84 gün süreyle yürütülmüştür. Balıklara günlük olarak doyuncaya kadar ve elle yem verilmiştir. Araştırmanın sonuçlarına göre balıkların büyüme performansı, yem kullanımı ve viserosomatik indeks değerleri kullanılan diyetlerden etkilenmemiştir (P>0.05). Ancak PTY ve PTY50/KY50 diyetleriyle beslenen balıkların hepatosomatik indeks değerleri diğer gruplardan daha yüksek bulunmuştur (P0.05). However, hepatosomatic index was significantly higher (<0.05) in fish fed with CSO and CSO50/CO50 diets. Fish fed CSO or CO diets had significantly lower levels of n-3 highly unsaturated FAs and increased levels of 18:2n-6 in the whole body FA composition (<0.05). Furthermore, liver had significantly higher levels of docosahexaenoic acid and arachidonic acid than those in the fish whole body. Results suggest that the 50% replacement of dietary fish oil by cotton seed oil and canola oils in equal amounts could be possible without compromising growth and overall well-being in the juvenile rainbow trout

The effects of dietary protein levels with amino acid supplementation on the growth performance, haematological profile and histology of meagre (Argyrosomus regius) in two different size classes

A 12-week feeding trial was conducted to estimate the effects of supplemented amino acids (lysine and methionine) with different dietary protein levels on growth, haematology and liver histology in meagre (Argyrosomus regius) at two different sizes: fingerling (15.2 g) and juvenile (44.4 g). Six practical diets were prepared, and three of these practical diets were formulated with 40 (P40), 44 (P44) and 48% (P48) crude protein without supplementation of amino acids. Other three diets having same protein levels were supplemented with lysine and methionine (P40AA, P44AA and P48AA) to bring these amino acids level up to that estimated to be at the least in the 48% protein diet. Final mean weight (FMW) and specific growth rate (SGR) of P48AA in fingerlings were higher than that of 40AA. According to FMW and SGR of juveniles, there was interaction found between dietary protein levels and the supplementation of amino acids. The FMW and SGR of meagre fed P44AA were higher than that of fish fed the other diets, except fish fed the P48. Economic profit index, packed cell volume and haemoglobin for juvenile meagre were significantly improved with the dietary protein level and amino acid supplementation. The liver tissues of the P48 group in both sizes displayed better structure compared with the other groups. In conclusion, dietary crude protein content of practical diets for juvenile meagre could be reduced from 48% to 44% by adding essential amino acids with an enhancement in growth, health and economic profit. © 2017 John Wiley & Sons LtdT.C. Gida Tarim ve Hayvancilik BakanligiThis study was funded by the Republic of Turkey Ministry of Food, Agriculture and Livestock, General Directorate of Agricultural Research and Policies with the Project Numbers 13/R&D/31. Special thanks go to Dr. Gu€ngo€r Muhtarog?lu and Muammer Karademir for providing the fish used in this study. The authors would like to acknowledge Assoc. Prof. Dr. Tu€lin Otbic©er Acar for the supports of statistical analysis. The authors are grateful to Muhammet Balcı, Mevlu€t Yalc©ın, Olkan S©entu€rk, Fatma Aydan Karakelle and Ku€bra Bozacı for their excellent technical assistance in fish rearing and sample collection. Some data of this study have been presented in Aquaculture Europe 2015, Rotterdam, Netherlands as a poster presentations on October 20–23rd, 2015

Potential of cottonseed oil as fish oil replacer in European sea bass feed formulation [Avrupa deniz levreği yem formulasyonunda pamuk tohumu yağının potansiyel olarak balık yağına İkamesi]

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. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey