Thesis (MSc) -- Stellenbosch University, 2004. / ENGLISH ABSTRACT: Standard histological procedures revealed that there are two types of glands in the
cloacal complex of the viviparous Cordylus cataphractus. These occur in the urodeal
region of the complex (called urodeal glands), and in the posterior proctodeum region
(called proctodeal glands). Urodeal glands are found in females only and differentiate at
sexual maturity. Proctodeal glands occur in both sexes and the dorsal and ventral
proctodeal glands are identical in structure. Seasonal activity in cloacal gland structure
and secretory was studied. Urodeal glands show distinct seasonal variation in
development and secretory activity, they become enlarged in vitellogenic females, remain
active during pregnancy, with glandular activity peaking around parturition. Proctodeal
glands, in contrast, show little or no seasonal variation in development or secretory
activity in both sexes. Secretion quantity, however, is highly variable among individuals
of the same sex, time of year, as well as reproductive stage, but evidently much less in
females than in males. Although the possible functions of the cloacal glands are still
unclear, two main functions are suggested: a) mechanical function such as lubrication or
a substrate for genital products and b) pheromonal communication. I propose that urodeal
glands are involved in some reproductive function rather than in social communication,
because very little secretion is found during the mating season and peak glandular activity
are evident around parturition. The opposite may be true for proctodeal glands, but
further investigation is needed, particularly chemical analysis of secretion and
behavioural manipulation, to determine the role of these glands in social communication. / AFRIKAANSE OPSOMMING: Standaard histologiese tegnieke dui aan dat daar twee tipes kliere voorkom in die
kloakale kompleks van die lewendbarende akkedis, Cordylus cataphractus. Die een
kliertipe word in die urodeale omgewing aangetref en staan bekend as die urodeaalkliere,
terwyl die ander groep in die posterior area van die proktodeum voorkom en
proktodeaalkliere heet. Urodeaalkliere word slegs in wyfies aangetref en ontwikkel eers
na volwassenheid bereik is. Proktodeaalkliere kom in albei geslagte voor en dorsale en
ventrale aspekte van hierdie kliere is identies aan mekaar. Die seisoenale aktiwiteit in
struktuur en sekresie-aktiwiteit van hierdie kloakale kliere is ondersoek in mannetjies en
wyfies wat gedurende verskillende maande van die jaar versamel is en dus in verskillende
voorplantingstadia was. Urodeaalkliere het duidelike seisoenale variasie vertoon wat
beide ontwikkeling van die klier en sekretoriese aktiwiteite betref. Die klier vergroot
tydens vitellogenese, bly aktief tydens swangerskap en bereik maksimale
aktiwiteitsvlakke rondom geboorte. In teenstelling hiermee het die proktodeaalkiere van
beide geslagte weinig of self geen seisonale variasie in hul ontwikkeling of sekretoriese
aktiwiteit getoon nie. Die hoeveelheid sekreet vrygestel was merkbaar minder in wyfies
as in mannetjies, maar hoogs veranderlik tussen individue van dieselfde geslag of
voortplantingstadium; of wat in dieselfde tydperk van die jaar versamel is. Alhoewel
funksies van kloakale kliere steeds onduidelik bly, word twee hooffunksies voorgestel: a)
‘n meganiese funksie, byvoorbeeld as smeermiddel of as ‘n substraat vir geslagsprodukte
en b) ‘n kommunikasie funksie, byvoorbeeld in die vrystelling van feromone. Ek stel voor dat die urodeaalkliere eerder by ‘n voortplantingsfunksie betrokke is, aangesien baie
min sekreet gedurende die paarseisoen vervaardig word terwyl klieraktiwiteit rondom
geboorte ‘n piek bereik. Die teenoorgestelde mag geld vir proktodeaalkliere, maar vereis
verdere ondersoek. Veral ‘n chemiese analise van die sekresie en gedragsmanipulasie sal
nuttig wees om ‘n moontlike rol van hierdie kliere in sosiale kommunikasie te bepaal.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/49884 |
| Date | January 2004 |
| Creators | Alblas, Amanda |
| Contributors | Flemming, Alexander F., Mouton, P. le Fras N., Stellenbosch University. Faculty of Science. Dept. of Botany and Zoology. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 136 leaves : ill. (some col) |
| Rights | Stellenbosch University |
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