饲料中铜浓度对异育银鲫和斑点叉尾鮰的影响

EFFECTS OF DIETARY COPPER AT DIFFERENT CONCENTRATIONS ON GIBEL CARP AND CHANNEL CATFISH

  • 摘要: 通过4周的生长实验,研究饲料中不同铜含量对异育银鲫(Carassius auratus gibelio) 初始体重(128.62.0) g和斑点叉尾鮰 (Ictalurus punctatus)初始体重(159.42.0) g的生长、饲料利用、血液生化以及组织中铜积累量的影响。两种实验鱼的实验饲料均以CuSO45H2O为铜源,铜含量分别为3.1(对照)、7.5、49.8、100.5、506.9、965.1和1491.1 mg/kg饲料。实验结果表明,异育银鲫摄食量(FI)随饲料中铜含量的增加无显著影响(P0.05),特定生长率(SGR)随着饲料中铜含量的增加而显著下降,在铜含量为1491.1 mg/kg时出现最低值(P0.05),饲料效率(FE)表现出与特定生长率相似的变化趋势。肝体比(HSI)和脏体比(VSI)均随着饲料中铜含量的增加而显著下降(P0.05),各处理组间的肥满度(CF)差异不显著(P0.05)。血浆中谷草转氨酶(GOT)在铜含量为7.5 mg/kg时达到最低值(P0.05),然而血浆中谷丙转氨酶(GPT)、铜锌超氧化物歧化酶(Cu-ZnSOD)活性及红细胞压积(Hct)、血红蛋白浓度(Hb)均不受饲料中铜含量的影响(P0.05)。肝脏中铜积累量随着饲料中铜含量的增加而无显著影响(P0.05),而肌肉中铜含量没有显著差异(P0.05)。斑点叉尾鮰FI随饲料中铜含量的增加而显著上升(P0.05),SGR随饲料中铜含量的增加表现出下降的趋势,但是差异不显著(P0.05),FE随饲料中铜含量的增加显著降低(P0.05)。HSI和CF随饲料中铜含量的变化而显著下降。Hct随铜含量的增加呈现出先上升后下降的趋势,当铜含量为100.5 mg/kg时达到最大值(P0.05),然而饲料铜水平对血浆中GPT、GOT、Cu-Zn SOD活性及Hb、VSI均无显著影响(P0.05)。铜在各组织中的积累表现出与异育银鲫相同的变化趋势。饲料中较高浓度铜可抑制斑点叉尾鮰和异育银鲫的生长和饲料利用,且异育银鲫对铜的耐受性高于斑点叉尾 。

     

    Abstract: Experiments were conducted for 4 weeks to investigate the effect of dietary copper at different levels on the growth, feed utilization, hematological parameters and the copper accumulation in gibel carp (Carassius auratus gibelio) CAS III initial body weight of (128.62.0) g and channel catfish (Ictalurus punctatus)initial body weight of (159.42.0) g. Seven semipurified diets were supplemented with dietary copper (CuSO45H2O) at graded levels (3.1, 7.5, 49.8, 100.5, 506.9, 965.1 and 1491.1 mg/kg diet). The results showed that feeding rate (FI) of gibel carp was not aftected by the increase in the dietary copper concentration (P0.05); in the contrast the specific growth rate (SGR) significantly decreased. The SGR reached the lowest value when dietary copper concentration was 1491.1 mg/kg (P0.05). The feed efficiency (FE) showed a similar trend to the SGR. The viscerosomatic index (VSI) and the hepatosomatic index (HSI) also significantly decreased along with the increase in the dietary copper level (P0.05), but the condition factor (CF) was not affected (P0.05). The activity of the serum glutamie-oxalacetic transaminase (GOT) was the lowest when dietary copper concentration was 7.5 mg/kg (P0.05). However, the concentration of the dietary copper did not affect hematocrit (Hct), hemoglobin (Hb), and the activities of serum glutamic-pyruvic transaminase (GPT) and copper-zinc superoxide dismutase (Cu-Zn SOD) (P0.05). As the concentration of the dietary copper increased, the copper accumulation in the liver and the fish body was significantly elevated accordingly (P0.05), but the accumulation in fish muscles was not affected (P0.05). Similarly in channel catfish the FI was not aftected by the concentration of the dietary copper rose (P0.05); the SGR showed an apparent but non-significant decrease (P0.05); the FE dropped along with the increase in the dietary copper level (P0.05); the HSI and the CF significantly decreased as well (P0.05); but the VSI was not affected by the concentration of the dietary copper (P0.05). In channel catfish, except for Hct (P0.05) the dietary copper level did not affect the activities of serum GPT, GOT, Cu-Zn SOD and Hb. The copper accumulation in channel catfish showed a similar trend to gibel carp. In conclusion, dietary copper at high concentrations could decrease the growth and feed utilization in gibel carp and channel catfish, and channel catfish could be more sensitive than gibel carp.

     

/

返回文章
返回