Influential Effect Of PH On Paa Spinosa Tadpoles Some Physiological Indexes

One-month old Paa spinosa tadpoles with a length of 1.694±0.121 cm and weight of 0.548±0.062 g were sampled for this research.The experiment of water was 48 h after aeration tap[ water water temperature(24 ± 0.2)? ? pH 7.30 ± 0.01 ? DO(7.30 ±0.01)mg/L]and seted six pH gradients(5.5?6.5?7.0?7.5?8.5 and 9.5)with still water and no feeding.After that,we observed the tadpol's behavior and tail skin appearance in chromatic aberration in Hunter L,A,B color value,and studied the effects of pH on their oxygen consumption rate?ammonia excretion rate and suffocation point,meanwhile studied the variations in the activities of antioxidant enzyme(SOD?CAT?SGH)on liver and ATP enzyme,antioxidant enzyme on tail skin an for pH stress and recovery.The results showed as follow:(1)Tadpole's distribution of water layer,cluster status and frequency of movement depend on pH closely.In pH 5.5-6.5 Experimental group The tadpoles of the frogs distributed on the upper part of the water body dispersedly and accompanied by floating head phenomenon;pH 7.0 experimental group and pH 9.5 experimental group spine frog tadpole distributed in the entire water body,and accompanied by floating head phenomenon;pH 7.5-8.5 The experimental group was distributed in the whole water body and was clustered;pH 5.5-7.0 experimental group tadpole motion frequency was significantly higher than other experimental groups;(2)Changes of Hunter L values of the skin color of the tails of the tadpoles at different pH conditions: The result showed that at pH 8.5,the L value was the smallest,and pH 8.5 was the critical value for significantly changing the color difference of tadpoles skin;(3)Effects of pH on the oxygen consumption rate of tadpoles like this: during pH 7.5 to 9.5 the average oxygen consumption rate in each period and in all night,and daily were not significantly different(P>0.05),but significantly higher than the other groups(P<0.05)So pH 7.5 is the lowest critical value for normal oxygen consumption characteristics of tadpoles;Effects of pH on the ammonia excretion rate of Tadpoles: Each experimental group showed a circadian variation ammonia average night> all day(P<0.05),and the average daily rate and ammonia excretion were night,day ammonia excretion rates were not significantly different(P>0.05),so the ammonia excretion rate of tadpoles is not affected under pH stress;Effects of pH on the oxygen content in the asphyxiation point: The oxygen content of asphyxia increased first and then decreased with the increase of pH,and the oxygen content was the lowest at pH 7.5.(4)The variation characteristic of activities of antioxidant enzyme on tadpoles liver under the situation of pH stress and recovering: PH 7.5 was the optimum pH of SOD and CAT in the tadpole liver,pH 8.5 was the highest critical value,and the recovery time was only 6 days to pH 7.0.GSH enzyme was not under stress at pH 7.5.;(5)The variation characteristics of activities of antioxidant enzyme and ATP enzyme on tail skin: PH 7.5 was the optimum value of pH and pH stress of SOD and CAT in tail skin of tadpole;pH 8.5 was the highest critical value,and recovery time was only 6 days to pH 7.0;ATPase was not under stress at pH 7.5.