Rev. Soc. Bras. Med. Trop. vol.10 número6

B IO LO G Y OF T R IA T O M IN A E (R E D U V IID A E , HEM IPTERA ) FROM NORTH

OF FO R M O S A C O U N TY (GOIÁS - B R A ZIL). I. LENG TH OF LIFE CYCLE OF

T R IA T O M A SÓ RD ID A (STAL. 1859).

Dalva A. M ello*

In the present paper the life cycle o f

T r ia to m a s ó rd id a

was studied. The mean length

from egg to adult was 213 days. The mean length in days from each stage was: 24.3

f± 1.30) fo r the first. 32.8 (± 1.45) (2nd), 36.1 (± 1.50) (3rd), 44.6 (± 1.85) (4th) and

52.0 (± 1.92) (5th).

The mean egg incubation períod was 23.2 (± 1.40). Overall m o rta lity was 18.8% and

egg viab ility was 82.5%.

IN T R O D U C T IO N

Triatoma sórdida

is a re d u v iid e x te n s iv e ly d is tr ib u te d th r o u g h o u t th e S o u th A m e ric a n c o n tin e n t4 . I t is fo u n d in d o m e s tic as w e ll as in w ild e n v iro n m e n ts . In th e f ir s t case, i t is u s u a lly fo u n d a ro u n d d w e llin g s , its p re fe rre d h a b ita t b e in g th e p o u lt r y y a rd , b u t in can a lso be fo u n d in p ig s tie s , c o rra is a n d o th e r p laces a d ja c e n t to h u m a n d w e llin g s . In São P a u lo S ta te , B ra z il,

T.

sórdida

w as fo u n d e s ta b lis h in g c o lo n ie s in s id e h o u se s 3, 8 ' 1 4 . In G o iá s S ta te , F o rm o s a C o u n - ty , B ra z il, s p e cim e n s o f th is species o f tr ia - to m id s w e re fo u n d in a h o u s e b y C a rv a lh o e t a l2 . H o w e v e r, th ese a u th o rs d id n o t m e n tio n th e d e v e lo p m e n ta l stage in w h ic h these ins ects w e re fo u n d . M e llo 10 in 1 9 7 6 , has fo u n d a d u lt s p e cim e n s o f

T. sórdida

in hou ses in th e same c o u n ty . T h e a u th o r b e lieve s th a t, in th is s itu a tio n , th e in se cts m ig h t have been a ttr a c te d b y lig h t. In a w ild e n v ir o n m e n t

T. sórdida

w as fo u n d in S ão P a u lo S ta te b y C o rre a e t a l3 in 1 9 5 9 , B a r r e to 1 in 1 9 6 6 , F o r a ttin i e t a l8 , in 1 97 1.

A s f o r its p la c e in th e e p id e m io lo g y o f C hagas disease,

T. sórdida

is c o n s id e re d a s e c o n d a ry v e c to r o f

Trypanosoma cruzi3

■ 4 . H o w e v e r, its s ig n ific a n c e w as c o n s id e re d b y R o c h a e S ilv a e t a l1 4 . and F o r a ttin i e t a l8 . These in v e s tig a to rs o b s e rv e d t h a t th e e lim in a - tio n o f p o p u la tio n s o f

T. infestans

in a d o m e s­ t ic e n v iro n m e n t w it h B H C fa v o rs an in crea se in p o p u la tio n s o f

T. sórdida.

L it t le is k n o w n a b o u t th e b io lo g y o f

T.

sórdida.

P in to 13 w as th e f ir s t t o s tu d y som e aspects o f th e b io lo g y o f th is h e m ip te ro u s in s e c t. D ia s 6 , in 1 9 5 5 , re p o rte d b r ie f ly o n th e life c y c le o f th is species in th e la b o ra to ry . P e rlo w a g o ra -S z u m le w ic z 1 1 ' 12 a n a ly s e d som e aspects o f th e b io lo g y o f

T.sordida

u n d e r la b o r a to r y c o n d it io n , a nd c o m p a re d i t w ith o th e r sp ecies o f tr ia to m id s .

I t is e v id e r it th a t la b o r a to r y research is necessary in o rd e r t o b e tte r u n d e rs ta n d th e im p lic a tio n s o f

T. sórdida

in th e tra n s m is s io n o f

T. cruzi.

T a k in g th is fa c t in t o c o n s id e ra tio n , th e a u th o r 's o b je c tiv e s w ill in v o lv e a series o f la b o r a to r y s tu d ie s o n several a spects o f th e

F a c u lty o f H e a lth Sciences, U n iv e rs ity o f B razilia. Th is w o rk was su pp orted , in p a rt, b v a gran t o f N ational Research C o u n cil o f B ra zil. (S IP /0 8 -0 3 2 — C N P q -€ 2 2 8 /7 5 ) and th e M in is try o f H e alth .

328 _{Rev. Soc. Bras. Med. Trop. Vol. X N ?6}

b io lo g y o f T r ia to m in a e f r o m N o r th p a r t o f F o rm o s a C o u n ty , G o iá s S ta te . T h is p a p e r is th e f ir s t r e p o r t f r o m series a n d i t d e s crib e s th e life c y c le o f

T. sórdida.

M A T E R I A L A N D M E T H O D S

1.

Origin o f the population studied

T h e p o p u la tio n o f

T. sórdida

s tu d ie d in th is p a p e r w as o rig in a te d f r o m a fe m a le in s e c t c a u g h t in th e fie ld , a lre a d y la y in g eggs. T h is fe m a le ca m e f r o m a p la ce a b o u t 1 5 6 k m n o r th - east o f B ra s ília , D F , B ra z il o n th e B R -0 2 0 h ig h w a y . A p o u lt r y y a rd , a p p r o x im a te ly 12 m fr o m a h u m a n d w e llin g , w as th e h a b ita t w h e re is w as fo u n d . T h e n u m b e r o f in d iv id u a is f r o m f ir s t in s ta r n y m p h t o a d u lt w as 2 5 0 , w h ic h c o rre s p o n d s t o 8 2 .1 % o f a li th e eggs la id b y th e o rig in a l fe m a le .

2.

Maintenance o f the population

T h e p o p u la tio n s tu d ie d w as fe d o n c e a w e e k o n p ig eo ns . T h e in se cts w e re le f t o n th e b ir d f o r a b o u t 2 0 m in u te s , in a d a rk e n v ir o n m e n t

T h e p o p u la tio n w as k e p t in th e f o llo w in g c o n ta i n ers:

a) F irs t a n d s e c o n d in s ta r n y m p h s — p la s tic c o n ta in e rs m e a s u rin g 5 ,5 c m in d ia m e te r b y 5 ,0 c m in h e ig h t

b) T h ir d , f o u r t h a nd f i f t h in s ta r n y m p h s — glass c o n ta in e rs m e a s u rin g 1 0 ,5 c m in d ia m e te r b y 9 ,5 c m in h e ig h t

c) A d u lts — glass c o n ta in e rs m e a s u rin g 2 4 ,5 c m in d ia m e te r b y 1 4 ,0 c m in h e ig h t

In s id e th e c o n ta in e rs th e re w e re c a rd b o a rd a c c o rd io n s a n d th e ir o p e n in g s w e re c lo s e d w it h an e la s tic -b o rd e re d screen.

T h e e n tir e p o p u la tio n w as k e p t in an in - s e c ta r iu m w it h o u t lig h t, 4 m lo n g b y 2 ,1 0 m w id e b y 3 ,2 0 m h ig h .

T h e te m p e r a tu r e a n d re la tiv e h u m id it y w e re c o n tr o lle d b y a th e r m o h id r o g r a p h ( W ith , L a m - b re c h t K G ). D u r in g th e o b s e rv a tio n p e r io d th e m ean te m p e r a tu re w as 2 3 .7 ° C a n d th e re la tiv e h u m id ity w as 7 4 ,1 % .

D a ily o b s e rv a tio n s w e re m a d e a n d d u ly a n n o ta te d .

F o r th e s ta tis tic a l a n a ly s is o f th e c y c le le n g th a n d o f th e d if f e r e n t stages, th e n u m b e r o f o b s e rv a tio n d a y s w as g ro u p e d in a c la s s /in - te rv a l, th e m eans b e in g c a lc u la te d in g ro u p s o f data.

C o m p a tib ility te s t w as used f o r th e cases w h e re a c e rta in n u m b e r o f in d iv id u a is h a d a d if fe r e n t c y c le le n g th f r o m th e m a jo r ity o f th e p o p u la tio n s tu d ie d .

R E S U L T S

T h e c o m p le te c y c le le n g th f r o m egg t o a d u lt la s te d an average o f 2 1 3 d ay s.

T h e egg in c u b a tio n p e r io d is s h o w n in ta b le 1. T h e m ean w as 2 3 .2 (± 1 .4) (T a b le 3 ) w ith 8 2 ,5 % o f v ia b le eggs (5 5 5 o b s e rv e d a n d 4 5 8 h a tc h e d ).

T h e d a y s o f o c c u re n c e o f e cdyse s, g ro u p e d in a class in te rv a l f o r th e 5 stages are s h o w n in ta b le 2 . O v e ra ll m o r t a lit y w as 1 8 ,8 % .

T h e fe m a le /m a le r a tio w as 1 1 5 /8 8 w it h a s e x u a l ra te o f 1.3.

T h e ecdyses w h ic h la s te d m o re th a n 1 0 0 d a y s w e re as fo llo w s :

T h e m e ta m o rp h o s e s o f 3 rd in s ta r n y m p h s w e re o b s e rv e d a t 1 1 5 , 1 5 0 , 1 7 8 , 2 4 5 , 2 4 8 d a y s ; th e m e ta m o rp h o s e s o f 4 th in s ta r n y m p h s w e re o b s e rv e d a t 1 1 3 , 1 1 5 , 1 3 5 (2 ), 1 3 8 , 1 4 4 , 1 48 , 1 5 0 , 1 7 1 , 1 8 6 , 2 5 2 , 2 8 5 , 3 1 6 , 3 2 3 d a y s ; th e m e ta m o rp h o s e s o f 5 th in s ta r n y m p h s w e re o b s e rv e d a t 8 0 ( 2 ) , 8 1 ( 2 ) , 8 3 , 8 5 , 8 7 , 1 1 4 , 1 2 0 (2 ), 1 2 1 , 1 4 2 , 1 9 9 , 2 5 5 , 3 3 0 ( 2 ) , 3 4 1 ( 2 ) , 4 5 0 ( 2 ) and 5 4 0 d ays.

T h e re s u lts o f th e c o m p a t ib ilit y te s t u sed in th e a n a ly s is o f th e in se cts w h ic h h ad ecdyses h ig h e r th a n 1 0 0 d a y s, in d ic a te d t h a t th ese are n o t c o m p a tib le w it h th e m a jo r ity o f th e p o p u ­ la tio n .

T A B L E 1

P e rio d o f in c u b a tio n o f eggs o f

T. sórdida

u n d e r la b o r a to r y c o n d itio n s .

In c u b a tio n d a y s

class in te rv a l Eggs

9 - 1 1 0

1 2 - 14 2 4

1 5 - 17 4 3

1 8 - 2 0 7 7

21 - 2 3 1 1 3

2 4 - 2 6 81

2 7 - 2 9 5 9

3 0 - 3 2 2 3

3 3 - 3 5 2 4

3 6 - 3 8 6

3 9 - 4 1 8

N 9 o f v ia b le eggs 4 5 8

V ia b le eggs (%) 8 2 ,5

NO V -D E Z/76 Rev. Soc. Bras. Med. Trop. 329

T A B L E 2

D u r a tio n in d a y s o f th e d if f e r e n t e v o lu tiv e stages o f

T. sórdida

E v o lu tiv e Ec d y s e s ^ ^ x . ^ ^ ^ 3 ^

days (class in t.)

N I N II N I I I N I V N V

5 - 9 0 1 0 0 0

1 0 - 14 3 5 3 0 0 0

1 5 - 19 3 9 2 0 0 0

2 0 - 2 4 9 8 2 4 21 0 1

2 5 - 2 9 2 5 7 3 57 8 4

3 0 - 3 4 6 5 3 6 0 4 5 7

3 5 - 3 9 2 19 16 31 5

4 0 - 4 4 0 17 13 3 6 2 8

4 5 - 4 9 4 16 10 2 8 3 8

5 0 - 5 4 3 8 12 13 4 9

5 5 - 5 9 0 1 3 1 15

6 0 - 6 4 2 1 3 1 5

6 5 - 6 9 5 3 6 10 3

7 0 - 7 4 6 0 2 6 12

7 5 - 7 9 1 0 0 5 8

8 0 - 8 9 0 0 2 5 10

9 0 - 9 9 0 0 3 2 4

+ 1 0 0 0 0 5 14 14

S u b to ta l 2 2 6 2 21 2 1 3 2 0 5 2 0 3

D ead 2 4 5 8 8 2

T o ta l 2 5 0 2 2 6 2 21 2 1 3 2 0 5

T A B L E 3

M o r t a lit y a nd m ean d u r a tio n o f d if f e r e n t e v o lu tiv e stages o f

T. sórdida

E v o lu tiv e

stages M ean D u r a tio n (da ys) M o r t a lit y (%) S u rv iv a l (%)

Eggs 2 3 .2 (± 1 .4 0 )

N I 2 4 .3 (± 1 .3 0 ) 9 .6 9 0 .4

N II 3 2 .8 (± 1 .4 5 ) 2 .5 9 7 .8

N I I I 3 6 .1 (± 1 .5 0 ) 3 .6 9 6 .3

N IV 4 4 .6 (± 1 .8 5 ) 3 .8 9 6 .2

330 _{Rev. Soc. Bras. Med. Trop. Vol. X N ?6}

C O M M E N T S

P in to 1 3 b r ie f ly s tu d y in g th e b io lo g y o f

T.

sórdida

u n d e r la b o r a to r y c o n d itio n s , o b s e rv e d th a t th e e g g -a d u lt c y c le la s te d f o r a p p ro x im a - te ly 5 m o n th s .

D ias6 fo u n d t h a t th e c y c le le n g th f o r

T.

sórdida

fe d o n c h ic k e n s w as 4 2 0 -6 5 9 d a y s a fte r th e e c lo s io n o f th e eggs.

T h e re s u lts fo u n d in th e p re s e n t s tu d y , w h e re th e m ean te m p e ra tu re a n d re la tiv e h u m i- d it y w e re 2 3 .7 ° C . a n d 7 4 ,1 % re s p e c tiv e ly , a n d th e ins ects w e re fe d o n p ig e o n s o n c e a w e e k , s h o w e d t h a t th e m ean e g g -a d u lt c y c le le n g th w as 2 1 3 d a y s o r a p p r o x im a te ly 7 m o n th s .

T h e o c c u re n c e o f ecdyses in n u m b e r o f d a y s n o t c o m p a tib le w it h th e m ea n f o r th e p o p u - la tio n s tu d ie d can p ro b a b ly be e x p la in e d as h a v in g been caused b y p h y s io lo g ic a l p ro b le m s . These p ro b le m s w o u ld be u n d o u b te d ly re la te d to in te rn a i a n d in d iv id u a l changes, s in ce th e e x te rn a i c o n d itio n s w e re n o t a lte re d d u r in g th e e x p e rim e n t. T h e h a lt in th e d e v e lo p m e n t o f som e tr ia to m id s c re a tin g a lo n g e r p e r io d in d a ys f o r th e 3 rd , 4 th a n d 5 th stages c o u ld have been caused b y a te m p o r a r y in t e r r u p t io n o f p h y s io - io g ic a l re a c tio n s re s p o n s ib le f o r th e ecdyses.

T h e v ia b ilit y fo u n d f o r eggs o f

T. sórdida

was s im ila r t o th e d a ta p re s e n te d b y P e rlo w - a g o ra 12 th a t is, 8 7 ,7 % .

T h e s u rv iv a l in th e im m a tu r e stages w h ic h v a rie d f r o m 9 0 ,4 % t o 9 9 ,0 % (T a b le 3 ) w as s u p e rio r t o t h a t fo u n d b y P e rlo w a g o ra 12 ( a ro u n d 8 9 % ).

T h e d iffe re n c e s in c y c le le n g th , w h e n c o m - p a re d t o th e re s u lts g ive n b y P in t o 1 3 a n d D ias6 can be e x p la in e d e ith e r b y g e n e tic d iffe re n c e s , ty p e

o f meai fed

t o th e

insects during the

e x p e rim e n t, o f b y d iffe re n c e s in te m p e ra tu r e a n d h u m id ity . U n f o r tu n a te ly , these tw o a u th o rs d o n o t m e n tio n th e la b o r a to r y c o n d i­ tio n s in w h ic h th ese e x p e rim e n ts w e re c a rr ie d o u t. C o rre a e t a l 5 . S tu d y in g th e life c y c le o f

T.

infestans

o b s e rv e d a n d c o n fir m e d th e re s u lts o f o th e r in v e s tig a to rs t h a t th e d iffe re n c e s in c y c le le n g th f o r th is sp ecies o f in se c ts are m a in ly re la te d t o te m p e ra tu re . T h is a u th o r o b ta in e d th e c o m p le te c y c le o f

T. infestans

o f 141 d a y s a t te m p e ra tu re s v a ry in g f r o m 2 5 t o 2 6 ° C a n d , 3 0 4 d a ys a t te m p e ra tu re s v a r y in g f r o m 19 to

2 6 ° C .

R e la tin g th e p ro b le m o f th e life c y c le le n g th o f tr ia to m id s to th e fr e q e n c y o f fe e d in g , F re ita s e t a l.9 o b s e rv e d t h a t

R. neglectus

h ad a s h o r t e r c y c le w h e n fe d o n c e a w e e k ( 8 5 ,9 ± 3 , 8 ) th a n w h e n fe d e v e r y , 14 d a ys (9 6 ,7 ± 4 , 1 ) .

RESUMO

Foi estudado no presente trabalho o ciclo biológico do

T ria to m a s ó rd id a

A média da

duração do ciclo de ovo a adulto fo i 213 dias. A média de duração em dias para cada

estágio fo i 24,3 (± 1,30) para o prim eiro, 32,8 (± 1,45) para o segundo, 36,1 (± 1,50) para

o terceiro, 44,6 (± 1,85) para o quarto e 52,0 (± 1,92) para o quinto.

A média do período de incubação dos ovos fo i 23,2 (± 1,40).

A mortalidade em todos ps estágios fo i 18,8% e a viabilidade dos ovos fo i 82,5%.

R E F E R E N C E S

1. B A R R E T T O , M . P. — A s p e c to s de e p id e - m io lo g ia da trip a n o s o m o s e a m e ric a n a , in ­ fe c ç ã o c o m fo c o s n a tu ra is , c o m e spe cial re fe rê n c ia à re g iã o N o rd e s te d o E sta d o de S ão P aulo. R ib e irã o P re to (Tese — F a c u ld a ­ d e de F a rm a c ia e O d o n to lo g ia ) , 1 9 6 6 .

2. C A R V A L H O , A . G . & V E R A N O , O . T . -E p id e m io lo g ia e P r o fila x ia d a D o e n ç a de C hagas e m G oiás.

Rev. Goiania Med. 2\

2 4 1 -2 6 6 , 1 9 5 6 .

3. C O R R E A , R. R. & F E R R E IR A , O . A . - D is tr ib u iç ã o g e o g rá fic a , h a b ita ts e in fe c ç ã o d e

Triatoma sórdida

(H e m ip te ra , R e d u - v iid a e ) n o E sta d o de S ão P a u lo .

Rev. Inst.

Med. Trop. São Paulo 1:

2 0 7 -2 1 3 , 1 9 5 9 .

N_{O V D E Z /7 6} Rev. Soc. Bras. Med. Trop. 331

5. C O R R E IA , R. R ., C A V A L C A N T I , A . S. & R A M A L H O , G . R. R . — C ic lo e v o lu tiv o e fases e v o lu tiv a s d o

Tríatoma infestans

T ra n s m is s o r d a D o e n ç a d e Chagas

Foi.

Clin. Biol.

7 :7 8 -9 0 , 1 9 7 3 .

6. D IA S , E. — N o ta s s o b re o te m p o de e v o lu ç ã o de a lg u m a s e spécies de tr ia to m i- nesos e m la b o r a tó r io .

Rev. Brasil. Biol.

15:

1 5 7 -1 5 8 , 1 9 5 5 .

7. D IA S , J. C. — O b se rva ç õe s s o b re o c o m p o r ­ ta m e n to de tr ia to m ín e o s b ra s ile iro s fr e n te a o je ju m , e m la b o r a tó r io .

Rev. Bras. Mal.

D. Trop. 17:

5 5 , 1 9 6 5 .

8. F O R A T T I N I , O . P., F E R R E IR A , O . A „ R O C H A E S I L V A , E. O ., R A B E L L O , E. X . & S A N T O S , J . L . F . d o s — A s p e c to s e c o ló g ic o s d a trip a n o s o m o s e A m e ric a n a

Rev. Saúde Publ. S. Paulo,

5 :1 6 3 - 1 9 1 , 1 9 7 1 .

9. F R E IT A S , M . G ., C O S T A , J . O . & C O S T A , H . M . A . — A lg u n s a s p e c to s da b io lo g ia d o

Rhodnius neglectus

L e n t, 1 9 5 4 (H e m ip te - ra, T ria to m in a e ) e m c o n d iç õ e s de L a b o ra ­ tó r io I. E v o lu ç ã o .

Arq. Esc. Vet.

7 3 :8 1 -8 7 , 1 96 7.

10. M E L L O , D . A . — Pesquisa e m A n d a m e n to , 1 9 7 6 .

1 1 . P E R L O W A G O R A -S Z U M L E W IC Z , A ., d a C R U Z , H . N . & d e A R A Ú J O , J . N . N . - S p ecie s a n d stage in te r a c tio n in th e fe e d in g b e h a v io u r o f v e c to rs o f Chagas disease (T h e im p o r ta n c e o f d e te rm in a n ts in p la n n in g f o r g re a te r e ffic a c y a n d s ta n d a r d iz a tio n o f X e n o d ia g n o s tic p ro c e d u re s )

Rev.

Inst.

Med.

t r o p .

São Paulo

7 5 :1 3 9 -1 5 0 , 1 9 7 3 .

12. P E R L O W A G O R A -S Z U M L E W IC Z , A . - L a b o r a to r y c o lo n ie s o f tria to m in e s , b io - lo g y , a n d p o p u la tio n d y n a m ie s

Int. Symp.

New App. Amer. Tryp. Res.

B e lo H o r iz o n ­ te , B ra z il. 1 8-21 M a rc h , 1 9 7 5 .

13. P IN T O , C. — F a c to s c u rio s o s s o b re a h io lo g ia d o

Tríatoma sórdida

( N o ta p ré v ia )

Rev. Bras. Med.

5 :3 0 5 , 1 9 4 9 .