B . M . Al - Chalabi
Bull. Iraq nat. Hist. Mus.
(2000) 9 (2): 37-43

UTTILIZATION OF LIPIDS AS SOURCE OF ENERGY

DURING HIBERNATION OF RANA RIDIBUNDA PALLAS, 1771

Alwan J. El-wailly and Ehsan F. Al-Jawhary
Department of Biology, College of Education (Ibn-Hhaitham) University of

Baghdad. Baghdad, Iraq

ABSTRACT
The aim of this study is to calculate the ene expenditure from fatty substance contents of the
frog. Rana ridibunda during its hibernation. It was found that, almost, all frogs enter
hibernation during the last week of December and emerge from hibernation during the first
week of March. Hence, January and February are considered the hibernation period.
December is the pre-hibernation period and March is the post-hibernation period. The
reduction in percent of body lipid during the hibernation period was 4.8% in males and 7.7%
in females. The reduction in percent of lipid of fat bodies during the hibernation period was
2.758% in males and 0.733% in females.
The calorific value of R. ridibunda lipid amounted to 12338.5 cal/gm. Therefore, energy loss
from lipid content of body tissue was 10.04 cal/gm! day in males and 16.10 cal/gm! day in
females. Energy loss from fat bodies during hibernation was 5.77 cal/gm of mass in males and
1.53 cal/gm of mass in females. The total energy losses during hibernation for R. ridibunda. in
Baghdad. on dry weight basis, averaged 15.81 cal/gm! day in males and 17.63 cal/gm! day in
females.

INTRODUCTION

It is now well established that amphibians utilize fat as a source of energy during dormancy
(savage, 1961;Sherwin. 1965: Mazur. 1967: Brenner. 1969: Fitzpatrick. 1976). Several
workers made Invetigations on changes in lipid weight of some organs in several species of
anurans. It was found that fat bodies and other energy depots cover metabolic requirements
before as well during and after hibernation. Kaloyianni et al. (1993) worked on the effect of
adenosine on glucose metabolism of R. ridibunda erythrocytes. Seymour (1973) found that
about half of the energy required during dormancy came from the fat bodies in spadefoot
toads (Scaphiopus). Beurden (1980) has formulated an energy model to predict survival of
frogs The pattern of utilization of energy depots varies greatly both between individuals
within a population of frogs and between populations inhabiting varies localities. It also varies
from year to year, probably depending upon prevailing feeding conditions (Jorgensen et al..
1979). Behrisch & Rauch (1981) and Bradford (1983) gave good information regarding
oxygen relation and energy metabolism of dormant amphibians. Storey & storey (1985) found
that freezing exposure of the grey tree frog I-Iyla versicolor resulted in using of anaerobic
glycolysis for energy production. It is widely believed that the body lipid and the most
conspicuous site of fat storage in the fat bodies, in anurans, serve as an energy depot primarily
during hibernation. Mazur (1967) has obtained the calorific values of the tissues and fat at
different time of the year for Bufo bufo (L.) and Rana arvalis Nilss. This author found that
energy loss during the winter-spring period due to disappearance of fatty and non-fatty
substances.

Inheritance of dark head
The present study was undertaken to calculate the energy expenditure (cal/gm/dry body
weight/day) from body tissue lipid and from the lipid of fat bodies during hibernation of male
and female frog Rana ridibunda. It is hoped that this work should add useful informations for
the adaptive physiology of amphibians.

MATERLALS AND METHODS

A total of 445 individuals (218 males and 227 females) of R. ridibunda were collected from
Baghdad and its suburbs each month from October 1988 to the end of May 1989. During each
sampling, water and air temperature was measured. Fat bodies were excised and weighed with
accuracy of 0.001 gm. Animal were weighed. excluded fat bodies, with the stomachs empty.
with an accuracy of 0.01 gm. Frogs and fat bodies were dried at 70 c to a constant weight,
then they weighed to determine dry weight. Rose’s (1967) method was used as a basis for
extracting fat. Fat was extracted frOm the dry material h means of a hot mixture of
chloroform and methanol until a clean extract was obtained. All calculation of fat content are
presented as a percentage of the dry mass. The percentage of fat contents found for each
sample and the mean value calculated. The caloric value (cal/gm/dry weight) of frog fat was
obtained by means of burning in an oxygen Bomb calorimeter. The student ‘t” test was
applied for ascertaining differences between mean figures for the content of fat in particular
periods of investigations.

RESULTS

Table (1) and Fig. (1) show air and water mean temperature during the period from October
1988 till May 1989. The lowest mean temperature was in January (5.7 c° I- 6.5 of air and 4 c°
+ 6.5 of water). In February. the mean temperature was 9.7 c° +- 3.8 of air and 8.3 c° +- 4 of
water. Then, the temperature was increased during March. April and May. Frogs entered
hibernation at the end of the last week of December and emerged during the first week of
March. Hence, January and February are considered as the period of hibernation. December is
the per-hibernation period and March is the post-hibernation period.
Table (2) shows means of dry body weight of males and females and the percent lipid content
of body tissue (December and March) and the variation in percent lipid content in the fat
bodies (October-May). The percent lipid content of body tissue of R. ridibunda was high in
both sexes during December (14.3% in males and 16.2% in females). In March, lipid content
of body tissue amounted 9.5% in males and 8.5% in females. Table (2) and Fig. (2) show the
cyclic changes in lipid content of bodies. In December. the content of fat body lipid was
higher in males (3.73% +- 0.5073) than in females (1.56% +- 0.3436). The difference in
means was highly significant (p< 0.05). In general, both in males and females, the lipid
content of fat bodies decreased in February (0.730%+-0. 1924 in males and 0.177% +-0.627
in females). In March, however, on difference in fat body lipid weight was observed between
the sexes (0.973% +- 0.3379 in males and 0.83 l%+-0.3975 in females). The mean value in
both were decreased in April. In May, the content of fat body lipid in male was significantly
higher than in females (2.380% +-0.7248 in males and l.076%+-0.3346 in females). The
percentage of lipid contents consumed during hibernation was determined from the difference
between and the amount of lipid calculated in March.
The calorific value of R. ridibunda lipid was 12,338.5 cal/gm. Table (3) shows energy losses
from lipid content of body tissue during hibernation, the percent lipid consumed during this
period was 4.8% gm in males and 7.7% gm in females. Therefore, the percent of lipid
consumed from the lipid of body tissue per gm/day was 0.56% in males and 0.8 1% in
females. Thus, the energy consumed during hibernation is 10.04% cal/gm! dry body weight!
day for males and 16.10 cal/gm dry body weight! day for females.

B . M . Al - Chalabi
Table (4) shows energy losses from lipid content of fat bodies during hibernation. It was 5.77
cal!gm dry body weight! day for males and 1.53 cal/gm dry body weight! day for females.
Therefore, the total energy losses during hibernation for R. ridibunda. on dry weight basis.
averaged 15.81 cal!gml day for males and 17.63 cal!gmlday for females.

Table (1): Air and water mean temperature (C°) in Baghdad during 1988 and 1989
Month Air temperature water temperature
October 1988 25.8+- 2.8 23.0 +-2.7
November 19.8+-1.3 16.6+-l.7
December 17.3+-5.1 l4.7+-3.2
January 1989 5.7+-6.5 4.0+-6.5
February 9.7+-3.8 8.3+-4.0
March 26.7+-9.1 23.7+-6.4
April 29.5+-3.5 24.0+-7.l
May 32.0+-l.4 29.0+-2.l

Table (2): Means of weights of dry body, percent body tissue lipid and percent fat body lipid
of Rana ridibunda during 1988 and 1989.
Month No. Sex Dry body

weight(gm)
lipid content of
body tissue
(%gm dry body
weight)

Lipid contentof fat
bodies (%gm dry
body weight)

October 25 M 6.25+-2.57 2.404+-0.4630
21 F 9.33+-4.15 1.906+-0.552l
November 42 M 6.13+-2.l0 1.650+-0.2815
F 7.95+-3.70 1.079+-+0.1755
December 20 M 7.I0+-2.00 14.3 3.731+-0.5073
23 F 9.70+-3.16 16.2 1.564+-0.3436
January 6 M 4.27+-0.98 0.984+-0.3070
8 F 6.12+-2.79 0.697+-0.2167
February 36 M 7.22+-2.29 0.730+-0.1924
36 F 9.22+-5.21 0.l77+-0.0627
March 50 M 5.77+-1.91 9.5 0.973+-0.3379
27 F 6.86+-3.37 8.5 0.83 l+-0.3975
April 22 M 6.88+-1.79 0.424+-0.1270
20 F 10.57+-5.23 0.659+-0.2640
May 14 M 6.82+-l.35 2.380+-0.7248
35 F 7.80+-2.82 1.076+-0.3346

Table (3): Energy losses from lipid content of body tissue (cal/gm/dry for body weight/day) of
Rana ridibunda during hibernation.
Sex Lipid
content of Body
dry body
weigh)tissue
(%gm

Lipid consumed
during
hibernation

Energy losses
(cal/gm/ dry
body weight!
day)

December March
M 14.3 9.5 4.8 10.004
F 16.2 8.5 7.7 16.10

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Table (4): Energy losses from lipid content of fat bodies (cal/gm dry body weight/ day) of
Rana ,-idibunda during hibernation.
Sex Lipid content of Fat bodies
(%gm dry body weight)

Lipid consumed during
hibernaticth

Energy losses
(cal/gm dry
body
weight/day)

December March
M 3.731 0.973 2.758 5.77
F 1.564 0.831 0.733 1.53

DISCUSSION

Storage and utilization of body lipid as energy source during hibernation is influenced by the
environmental temperature as well as physiological changes within the animal (Savage, 1961:
Brenner, 1969). The lowest mean temperature of air and water (in Baghdad during 1988-
1989) was recorded during January and February. Hence, these two months are considered as
the period of hibernation for R. ridibunda (Table 1 and Fig. I). Table (2) shows the percent
lipid content of body tissue (excluded the lipid of fat bodies). In December. it was 14.3% in
males and 16.2% in females and the percent lipid content in March (after hibernation) was
9.5% in males and 8.5% in females. therefore, during both sexes utilization lipid, but the
amount of lipid consumption per day was higher in females than in males. Previous worker
showed that oogenesis continues throughout dormancy in amphibia and fat reserves are
essential for normal egg development (Smith,1950: Bush. 1963: Mizell. 1964: Brenner.
1969). Rose (1967) showed in R. nigroniaculata relative weight of ovaries tripled during
hibernation while no significant development was observed testes (Maruyama, 1979). Lipid
content in fat bodies of R. ridibunda fluctuates in both sexes. In December. the content of fat
body lipid was significantly higher in males than in females (Table 2 and Fig. 2). Fat bodies
of both sexes were approximately equal in March and than decreased in April (breeding
season). In May (after the breeding season), an increase in fat body weight is observed.
Studies on annual cycles in amphibian fat bodies support the idea that the fat bodies in
temperature zone anurans reach minimum size around the breeding time or after the spawning
period and reach their maximum size in autumn or before hibernation (Jorgensen et al.. 1979).
Smith (1950) found that fat body of R. temporaria attains maximum development in October
(before hibernation). This being followed by a decrease through the winter and it fall to a
minimum at the spawning season.

Tables (3 and 4) show the energy losses from lipid content of body tissue and of fat bodies.
respectively. The total energy losses during hibernation averaged 15.8 cal/gm day in males
and 17.63 cal/gm! day in females. From the investigation of Mazur (1967). concerning total
energy losses during the winter and the breeding season for B. bufo and R. arvalis with wet
weight averaged 47.99 cal/ 24 hours of B. bufo and in R. arvalis 14.00 cal/ 24 hours.
However, it most be noted that Mazur (1967) used known caloricity of frog fat (9361.96
cal/gm). and he did not take in consideration the sex of the investigated amphibians.

LITERATURE CITED

Behrish.H.W. & Rauch. J.C. 1981. Ketone bodies: a source of energy during hibernation.
can. .1. Zool., 59(5): 754-760.

Beurden. E.K. 1980. Energy metabolism of dormant Australisn water-holding frogs

Cvclorana platycephalus. Copeia, No. 4:787-799.

B . M . Al - Chalabi

Bradford. D.F. 1983. Winter Kill oxygen relation and energy metabolism of a submerged

dormant amphibian Rana muscosa. Ecol., 64(5): 1171-1183.

Brenner, F.J. 1969. The role of temperature and fat deposition in two species of frog.

Herpetological. 25:105-1 13.
Bush. F.M. 1963. Effect of light and temperature on the gross composition of the toad, Bufo

fowleri. I. exp. Zool., 153:1-13.

Fitzpatick, L.C. 1976. Life history of a storage and utilization of lipid for energy in

amphibian. Amer. Zool., 16:725-732.

Jorgensen, C.B. Larseen. L.O. & lofts, B. 1979. Annual cycles of fat bodies and gonads in the

toad Bufo bufo bufo (L.) compared with cycles in other temperature zone
anurans. Biol. Skr.. 22(5): 1-37.

Kaloyianni. M.; Michaelidis, B. & Moutov, K. 1993. Effect of adenosine on glucose

metabolism of Rana ridibunda erythrocytes. I exp. Biol.. 177:41-50.

Krawzyk. S. 1968. Fat and water content in some organs of the common frog Rana temporaria

L. in the middle period of hibernation. Acta biol. Cracove Zool., 11:282-294.

Maruyama. K. 1979. Seasonal cyckes in organ weights and lipid composition in the liver, fat

body and gonads of Rana esculenta. Boll. Zool.. 50:227-23.

Mazur. 1. 1967. Seasonal variations in the energy reserves of Bufo bufo (L.) and Rana arvalis

Nilss. Anura in poland. Ekol. Pol., l5(ser. A): 607-6 13.

Mizell. S. 1964. Seasonal differences in spermatogenesis and cogenesis in Rana pipiens.

Nature, 30(4935); 875-876.

Morton, M.L. 1981. Seasonal changes is in total body lipid and liver weight in the Yosmite

toad. Copeia, No. 1:234-238.

Rose. F.L. 1967. Seasonal changes in lipid levels of the salamander Amphiuma means.

Copeia, No. 3:662-666.

Savage, R.M. 1961. The ecology and life history of the common frog. Rana temporaria

temporaria. Pitman, London.

Seymour. R.S. 1973. Energy metabolism of dormant spadefoot toad (Scaphiopus). Copeia,

No. 3 :43 5-445.

Sherwin. M. 1965. Seasonal changes in energy reserves in the common frog. Rana pip/ens. .1.

Cell Coinp. Physiol., 66:25 1-258.

Smith, C.L. 1950. Seasonal change in blood sugar. fat body, liver glycogen and gonads in the

common frog, Rana temporaria. I exp. Biol. .26:412-429.

Storey. J.M. & Storey, K. B. 1985. Adaptations of metabolism for freeze tolerance in the grey

tree frog, Hyla versicolor. Can. I ool,. 63 :49-54.

Inheritance of dark head

B . M . Al - Chalabi

Bull. Iraq nat. Hist. Mus.
(2000) 9 (2): 37-43

Ranaاستهالك الدهون كمصدر للطاقة خالل فترة سبات ضفادع المستنقعات
ridibunda

علوان جاسم الوائلي و احسان فليح الجوهري

قسم علوم الحياة، كلية التربية ابن الهيثم، جامعة بغداد

الخالصة

تا نتيجـة ان الغرض من هذه الدراسة هـو قيـاس مقـدار الطاقـة الـيت يسـتهلكها ضـفدع املسـتنقعا
وقد اظهرت الدراسات بان معظم الضفادع تقريبـاً . استهالك الدهون اجلسمية خالل فرتة السبات

تدخل فـرتة السـبات خـالل االسـبوع االخـري لشـهر آذار، وعلـى ذلـك اعتـرب كـل مـن شـهري كـانون
ر آذار كما اعترب كانون االول فرتة ما قبـل السـبات وشـه. الثاين وشباط فرتة السبات هلذا الضفدع

.فرتة ما بعد السبات
يف % ٧,٧بلــغ اخنفــاض يف النســبة املئويــة يف دهــون االجســام الدهنيــة خــالل فــرتة الســبات و

يف الذكور % ٢,٧٥٨وبلغ اخنفاض النسبة املئوية يف دهون االجسام خالل فرتة السبات . االناث
كميــــة الســــعرات احلراريــــة لكــــل غــــرام دهــــين مــــن دهــــون ضــــفدع املســــتنقعات وبلغــــت ٠,٧٣٣و

.سعره ١٢٣٣٨,٥
ســـعره ببـــذكور و ١٠,٠٤ومـــن هـــذا بلغـــت كميـــة الطاقـــة املفقـــودة مـــن دهـــون انســـجة اجلســـم

امــا الطاقــة املفقــودة مــن دهــون االجســام الدهنيــة اثنــاء فــرتة . سـعرة لالنــاث يف اليــوم الواحــد ١٦,١
سـعره لالنـاث يف اليـوم لكـل غـرام مـن وزن احليـوان ١,٥٣سعره للذكور و ٥,٧٧السبات فبلغت

ومن هذا نستنتج ان مقدار الطاقة الكلية املفقودة اثناء فرتة سبات ضفدع املستنقعات يف . اجلاف
سـعره لالنـاث يف ١٧,٦٣سـعره للـذكور و ١٥,٨١بغـداد، نسـبة اىل وزن احليـوان اجلـاف، بلغـت

.اليوم الواحد