I

Asiatic Herpetological Research

February 1992"

Vol.4, pp. 137-140|

Electrocardiogram Research on the Chinese Alligator (Alligator sinensis)

HUIQING GU

RONGWEN RUAN AND ZHENG DONG ZHANG211,Hangzhou Teachers College, Hangzhou, Zhejiang, ChinaAnhui Research Center for Chinese Alligator Reproduction, Xuanzhou, Anhui, Chinal

2Abstract. -This paper is a report on the determination and analysis of the electrocardiogram of theFrom
Chinese Alligator (Alligator sinensis) under conditions of different air temperatures all year round.
the determination and analysis mentioned above, we discovered that the electrocardiogram of the Chinese
Alligator consists of a P wave, QRS waves and aT wave.

Key words: Reptilia, Crocodilia, Alligatoridae, Alligator sinensis, China, electrocardiogram.

Introduction

The Chinese Alligator (Alligatorspecies of crocodilian
endemic to China. In 1987, we began tocollect data about the electrocardiogram ofChinese Alligators under conditions ofsinensis)

isa

different air temperatures throughout theyear at the Anhui Research Center ofAlligators' electrocardiogram waves aresmall.
Electrocardiogram waves of I
standard limb lead are so low, even theof it can hardly be
the data used in
Therefore
distinguished.
this paper are all from the determinationfrom the II standard limb lead.

components

reproduction, ecology, andphysiology of Chinese Alligators. Here is

The electrocardiogram of a Chinese
Alligator basically consists of a P wave,
QRS waves and a T wave (Fig. 1). Boththe P wave and the R wave are positive, theT wave is reverse, and the QS waves are

the detailed report of the results.

not clear.

Chinese Alligator Reproduction. We hopethat these data may be applied to studies ongrowth,2).

Methods3).
isThe Anhui Research Center for Chinese
Alligator Reproduction supplied nine 6
year-old adult female Chinese Alligators
weighing 7.3 to 14.6 kg for theUsing a XDH-3 hot-pen
experiments.
electrocardiograph made in China, werecorded I, II, and III standard limb leads
atwith the standard voltage of 1 mv=1025
the paper passing speed ofpersecond. Laying on its back with four legs
fixed to the operating table, themmmm

Chinese Alligator's
electrocardiogram was determined byhaving four needle-like electrodes made byourselves being placed at the four points
beneath the skin which are relevant tostandard limb leads after it calmed down.
unanesthetizedResults1).

The

amplitudes

The amplitude of the Q wave, which

made up of Pr and PI is the smallest.

The time continued, which is at an averageof about 0. 1 8 seconds, is short. The timedifference between Pr and PI is about 0.09
seconds. The crests of the P wave arerate of appearance ismoderate (Table 1). Data show that the Pwave does not appear during thehibernating period (from the last-ten-day
period of November to the last-ten-day

round and theperiod of April of the next year). The rateof appearance is the highest from May toJune.
4).
QRS waves are the main waves.
The amplitude of the R wave is the greatest
and the crests of it are pointed. The time
continued, which is at on average about
0.14 seconds, is quite short. The rate ofappearance is the highest (Table 1).

ofChinese© 1992 by Asiatic Herpetological Research5).

The amplitude of the reverse T

Asiatic Herpetological ResearchVol. 4, p. 138

February 1992pvi

B-if-.-{'.

Pr-pi,-P'<m*r^
133

L_;"RAA

DFIG. 1. The electrocardiogram of the Chinese Alligator (Alligator sinensis ) under conditions of different
temperatures as determined in 1988. A. April 8, 14° C. B. June 20. 21° C. C. Oct. 3, 16° C. D. Dec. 9,4°C.

February 1992

TABLE 1.

Asiatic Herpetological ResearchVol. 4, p. 139

Changes in the electrocardiogram of the Chinese Alligator at different temperatures.

Asiatic Herpetological ResearchVol. 4, p. 140

depend largely on the external environment.
When air temperature goes up, it becomes
nimble, its heart rate quicker and its
metabolization active; when the temperaturegoes down, it becomes sluggish, its heart
rate gets

slower andits

metabolization

February 1992

RUAN, R.,R. SONG, AND Z.ZHANG.

1988.

[Atentative report on the electrocardiogram studyof Chinese Alligator].

Zoological Research

9:82-83. (In Chinese).

WEN, Y., AND M. REN.

1987.

[The ABC ofPp. 2-23. In Shanghai 1st
Medical College Physiology of the HumanElectrocardiogram].

drops.

Body. People's Publishing House of Medical

Literature Cited

BLACKFORD, L. M.

The heart and1956.
electrocardiogram of an Alligator. Circulation
14:1114-1116.

Sciences, 147 pp. (In Chinese).

WILBER, C. G.

1960.

Effect of temperature on

the heart in the alligator.

American Journal of

Physiology 198(4):861-863.