离水停食胁迫对中华鳖(Trionyx sinensis)翻身能力、血清生化、裙边质构及脏器相关功能酶活力的影响

EFFECTS OF AIR EXPOSURE AND STARVATION STRESS ON THE FLIPPINGABILITY,SERUM BIOCHEMISTRY,SOFT TISSUE SKIRT QUALITY,ANDORGAN-RELATED ENZYME ACTIVITY IN CHINESE SOFT-SHELLED TURTLESTRIONYX SINENSIS

中华鳖(Trionyx sinensis)历来有活品消费的习惯,离水停食是其批量销售环节必须承受的胁迫。因此,探究离水停食对其商品价值的影响过程与机制,对于明确其活体销售货架期具有重要指导价值和现实意义。以2020年5月20日同池起捕后离水停食处理0 d(S_(0)实验组)、4 d(S_(4)实验组)、8 d(S_(8)实验组)、12 d(S_(12)实验组)、16 d(S_(16)实验组)的雄性商品鳖[平均体质量(546.86±94.70)g]为研究对象,在常温条件下较系统开展了离水停食对其翻身能力、血清生化、裙边质构及脏器酶活力的影响研究。结果表明:(1)实验鳖连续翻身次数呈S_(4)≈S_(8)>S_(0)≈S_(12)≈S_(16),且均主要集中于1 min内;(2)血清TP、ALB、TC、LDL-C均无组间差异(P>0.05),GLU-O呈S_(0)≈S_(4)≈S_(8)≈S_(12)>S_(16),TG和HDL-C除S_(4)、S_(8)的TG含量小于S_(0)(P<0.05),S_(12)的HDL-C含量大于S_(0)(P<0.05)外,其余实验组间均无差异(P>0.05);(3)所测7项裙边质构指标中,仅硬度与连续翻身次数的排序完全重合,均呈S_(4)≈S_(8)>S_(12)≈S_(16);(4)肝脂肪酶和胃蛋白酶活力分别呈S_(4)>S_(0)≈S_(8)≈S_(12)≈S_(16)和S_(0)≈S_(16)>S_(4)≈S_(8)≈S_(12),肠淀粉酶活力除S_(16)实验组显著大于S_(0)、S_(4)(P<0.05)外,其余均无组间差异(P>0.05);(5)肝脏ATP酶和抗氧化酶活力随离水停食时间的延长总体上均呈阶梯式上升趋势,心脏抗氧化酶活力总体上在离水停食0~4 d、4~12 d、12~16 d分别呈下降、稳定和上升趋势,肺抗氧化酶活力总体上在0~4 d、4~8 d、8~12 d和12~16 d依次呈上升、下降、稳定和再次上升的趋势,S_(4)、S_(8)和S_(12)间在各脏器抗氧化酶活力值排序上明显表露错位的仅为脾脏GSH-PX,呈S_(4)<S_(12)<S_(8)(P<0.05)。研究结果可为中华鳖的生理生态研究和活销货架期的编制提供基础资料。

Chinese soft-shelled turtles have long been consumed as live products,and air exposure and starvation are inevitable environmental stresses during bulk sales.Therefore,exploring the impact of air exposure and starvation on the commercial value of Chinese soft-shelled turtles and its mechanisms is of great practical significance for determining the shelf life of live sales.In this study,male commercial turtles[average mass(546.86±94.70)g]subjected to air exposure and starvation treatment for 0 d(S_(0)group),4 d(S_(4)group),8 d(S_(8)group),12 d(S_(12)group),and 16 d(S_(16)group)after being caught from the same pool on May 20,2020,were used as research subjects.The effects of air exposure and starvation on their flipping ability,serum biochemistry,soft tissue skirt quality,and organ enzyme activity were systematically studied under normal temperature conditions.The results show that:(1)The consecutive flipping frequency of experimental turtles was S_(4)≈S_(8)>S_(0)≈S_(12)≈S_(16),mainly concentrated within 1 minute;(2)There were no significant differences in serum TP,ALB,TC,and LDL-C between groups(P>0.05).GLU-O showed S_(0)≈S_(4)≈S_(8)≈S_(12)>S_(16),TG,and HDL-C,except that TG content in S_(4)and S_(8)was lower than that in S_(0)(P<0.05),and HDL-C content in S_(12)was higher than that in S_(0)(P<0.05),there were no significant differences between other experimental groups(P>0.05);(3)Among the seven measured soft tissue skirt quality indicators,only hardness completely coincided with the order of consecutive flipping frequency,which was S_(4)≈S_(8)>S_(12)≈S_(16);(4)Hepatic lipase and gastric protease activities were S_(4)>S_(0)≈S_(8)≈S_(12)≈S_(16)and S_(0)≈S_(16)>S_(4)≈S_(8)≈S_(12),respectively.Except for the significantly higher intestinal amylase activity in the S_(16)group than in the S_(0)and S_(4)groups(P<0.05),there were no significant differences between other groups(P>0.05);(5)Hepatic ATPase and antioxidant enzyme activities showed a stepwise upward trend with the extension of air exposure and starvation time.Cardiac antioxidant enzyme activities showed a downward trend from 0 d to 4 d,stabilization from 4 d to 12 d,and an upward trend from 12 d to 16 d.Pulmonary antioxidant enzyme activities showed an upward trend from 0 d to 4 d,a downward trend from 4 d to 8 d,stabilization from 8 d to 12 d,and a subsequent upward trend from 12 d to 16 d.Among S_(4),S_(8),and S_(12),only splenic GSH-PX enzyme activity showed a clear misalignment in the order of enzyme activities,with S_(4)<S_(12)<S_(8)(P<0.05).The results of this study can provide basic data for the physiological and ecological research of Chinese soft-shelled turtles and the establishment of live sales shelf life.