Çipura (Sparus aurata, Linneaus 1758) larvalarının kortizol seviyeleri üzerine ticari besleme prosedürünün etkileri
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Dosyalar
Tarih
2014
Yazarlar
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Yayıncı
Hatay Mustafa Kemal Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışmanın amacı çipura larvalarının (Sparus aurata) kortizol seviyeleri üzerine ticari yemler Gemma Micro (50-100 µ) ve Caviar (100-200µ) ve canlı yemlerin Zenginleştirilmiş Rotifer, Artemia naupli ve Artemia metanaupli etkilerini belirlemekti. Aynı zamanda, larvaların proteaz aktiviteleri üzerine kullanılan ticari ve canlı yemlerin inhibisyon etkileri de belirlendi. Çipura larvalarının prelarval aşamasında gözlenen en düşük ve en yüksek proteaz aktiviteleri sırasıyla 0,77±0,36 U/mg protein (0. gün) ve 4,77±0,7 U/mg protein (4. gün) oldu. Larvaların postlarval aşamasında gözlenen en düşük ve en yüksek proteaz aktiviteleri sırasıyla 5,75±0,51 U/mg protein (25. gün) ve 111,57±0,74 U/mg protein (15. gün) oldu. Zenginleştirilmiş rotiferler en düşük proteaz aktivitesine (17,98±2,82 U/mg protein) sahipti. Artemia naupli ve Artemia metanaupli'nin proteaz aktiviteleri sırasıyla 34,67±0,88 U/mg protein ve 317,16±2,67 U/mg protein olarak bulundu. Canlı yemler, zenginleştirilmiş rotiferlerle beslemenin 10. günü dışında larvaların proteaz aktiviteleri üzerine pozitif katkılara sahipti. Gemma Micro (50-100 µ)'nun en düşük inhibisyon yüzdesi %13,17 (5. gün) olarak belirlendi.. Gemma Micro (50-100 µ) 20. ve 25. günlerde çipura larvalarının proteaz aktiviteleri üzerinde Caviar (100-200 µ)'dan daha düşük inhibisyonlara sahipti. Çipura larvalarının kortizol değerleri arasında önemli farklılıklar gözlendi (p<0,05). Çipura larvalarının en düşük ve en yüksek kortizol değerleri sırasıyla 0,099±0,009 ng/g (35. gün) ve 4,033±0,38 ng/g (10. gün) olarak bulundu. Çipura larvaları, anaçlardan gelen kortizol çıkıştan sonra prelarval dönemde düşürülememesinden dolayı ilk beslemenin başlangıcında yüksek kortizol değerlerine sahipti (1,199±0,15 ng/g). Sonuç olarak; 1) İlk beslemenin başlangıcında yüksek kortizol değerlerinin sebepleri gelecekte araştırılması gerekir 2) Çipura larvalarının ilk 10 günlük besleme periyodu, bu aşamada kullanılan rotiferlerin çipura larvalarının proteaz aktiviteleri üzerindeki negatif etkileri ve besinsel yetersizliklerinden dolayı kritik bir öneme sahiptir 3) Kuru yemlere geçiş aşamasında Artemia naupli ve Artemia metanaupli ticari yemlerle başarılı bir şekilde kullanılabilirken, zenginleştirilmiş rotiferlerin ticari yemlerle kullanımı önerilmez 4) Gemma Micro (50-100 µ), Artemia naupli ile birlikte daha erken dönemlerde kullanılabilir.
The aims of this study were to determine the effects of commercial diets (Gemma Micro (50-100 µ) and Caviar (100-200µ)) and live foods (Enriched Rotifer, Artemia nauplii and Artemia metanauplii) on the cortisol levels of the gilthead seabream (Sparus aurata) larvae and also, the inhibition effects of commercial diets and live foods used on protease activities of larvae. The lowest and highest protease activities observed in the prelarval stage of gilthead seabream larvae were 0.77±0.36 U/mg protein (day 0) and 4.77±0.7 U/mg protein (day 4), respectively. The lowest and highest protease activities observed in the postlarval stage of larvae were 5.75±0.51 U/mg protein (day 25) and 111.57±0.74 U/mg protein (day 15), respectively. Enriched rotifer had the lowest protease activity (17.98±2.82 U/mg protein). The protease activities of Artemia nauplii and Artemia metanauplii were found as 34.67±0.88 U/mg protein and 317.16±2.67 U/mg protein, respectively. Live foods had positive contributions on protease activities of larvae except for 10th day of feeding with enriched rotifer. The lowest inhibition percent of Gemma Micro (50-100 µ) was determined as 13.17% (day 5). Gemma Micro (50-100 µ) had lower inhibitions on protease activities of seabream larvae than those of Caviar (100-200 µ), especially day 20 and day 25. The significant differences between cortisol levels of seabream larvae were observed (p<0.05).The lowest and highest cortisol levels of seabream larvae were found 0.099±0.009 ng/g (day 35) and 4.033±0.38 ng/g (day 10), respectively. Seabream larvae had high cortisol levels at the beginning of exogenous feeding due to the maternal cortisol was not reduced in prelarval stage after hatching (1.199±0.15 ng/g). In conclusion, (1) the reasons of the high cortisol levels at the beginning of exogenous feeding should be investigated in future, (2) the first 10-day feeding period of seabream larvae had a critical importance due to the rotifers used in this stage are the nutritional deficiencies and the negative effects on protease activities of seabream larvae, (3) Artemia nauplii and Artemia metanauplii in weaning stage can successfully be used together with commercial diets but not the enriched rotifer, (4) Gemma Micro (50-100 µ) can be used in earlier periods together with Artemia nauplii.
The aims of this study were to determine the effects of commercial diets (Gemma Micro (50-100 µ) and Caviar (100-200µ)) and live foods (Enriched Rotifer, Artemia nauplii and Artemia metanauplii) on the cortisol levels of the gilthead seabream (Sparus aurata) larvae and also, the inhibition effects of commercial diets and live foods used on protease activities of larvae. The lowest and highest protease activities observed in the prelarval stage of gilthead seabream larvae were 0.77±0.36 U/mg protein (day 0) and 4.77±0.7 U/mg protein (day 4), respectively. The lowest and highest protease activities observed in the postlarval stage of larvae were 5.75±0.51 U/mg protein (day 25) and 111.57±0.74 U/mg protein (day 15), respectively. Enriched rotifer had the lowest protease activity (17.98±2.82 U/mg protein). The protease activities of Artemia nauplii and Artemia metanauplii were found as 34.67±0.88 U/mg protein and 317.16±2.67 U/mg protein, respectively. Live foods had positive contributions on protease activities of larvae except for 10th day of feeding with enriched rotifer. The lowest inhibition percent of Gemma Micro (50-100 µ) was determined as 13.17% (day 5). Gemma Micro (50-100 µ) had lower inhibitions on protease activities of seabream larvae than those of Caviar (100-200 µ), especially day 20 and day 25. The significant differences between cortisol levels of seabream larvae were observed (p<0.05).The lowest and highest cortisol levels of seabream larvae were found 0.099±0.009 ng/g (day 35) and 4.033±0.38 ng/g (day 10), respectively. Seabream larvae had high cortisol levels at the beginning of exogenous feeding due to the maternal cortisol was not reduced in prelarval stage after hatching (1.199±0.15 ng/g). In conclusion, (1) the reasons of the high cortisol levels at the beginning of exogenous feeding should be investigated in future, (2) the first 10-day feeding period of seabream larvae had a critical importance due to the rotifers used in this stage are the nutritional deficiencies and the negative effects on protease activities of seabream larvae, (3) Artemia nauplii and Artemia metanauplii in weaning stage can successfully be used together with commercial diets but not the enriched rotifer, (4) Gemma Micro (50-100 µ) can be used in earlier periods together with Artemia nauplii.
Açıklama
Anahtar Kelimeler
Su Ürünleri, Aquatic Products
