CBC'S of the ten animals all fell within, or on the periphery of the range of norms for
swine (Table 1). The research animals consisted
of pigs ranging in age from approximately one to seven years. All animals came from the
same area on Malo Island. Upon first observation (Table 2), the hormonal values of the representative samples cannot by themselves be
interpreted. The ratios of estradiol to testosterone were generated and the following
general conclusions may be drawn. Ratios greater than unity have been generally designated
as female and those less than one generally designates maleness(27).Like the two normal
males, all seven of the intersexes showed ratios less than 1.0. These observations seem to
support the theory that Vanuatu's intersexual pigs are actually mal-developed boars. Pig
"B", said by locals to be a pregnant female, showed a progesterone level of 10.6
ng/ml, consistant with that of a pregnant sow.
The results of the Dihydrotestosterone (DHT) test on the sera of pigs D,E,F,J,K,L,M
were consistent with maleness. Of the 54 animals on which external examinations were
conducted, there was a high degree of variability, the most common occurrences were in
testicular (number, size, and location) and urogenital configuration. Findings for the
intersexes varied from very "female" looking external genitalia with no
testicles to a descended scrotal sac containing two large well-developed testicles. Within
this range were many different testicular presentations including an empty scrotal sac,
one degenerate descended testicle, one large testicle, and one large and one small
testicle represented. Of the animals examined, 61% or 33 animals exhibit no testicles
whatsoever, 10 (or 19%) possessed 2 well-formed scrotal testicles, 8 (or 15%) had 1 normal
descended testicle, and the remaining 5% had 1 small and 1 large or 1 small testicle
present. As the intersexes' testicular development approached that of the "normal
male" condition, there was a corresponding change in the position and length of the
ventral labial commissure (V.L.C.) and the urogenital aperture. When there were no
testicles or scrotum present, the vulva seemed almost undifferentiable from that of the
normal female organ except possibly for a slight reduction of the urogenital opening, and
the presence of the corpus cavernosum (C.C.) may push the (V.L.C.) dorsally and laterally.
The terminal end of the urethra is distinguished from the corresponding structure of the
normal female by the presence of the bulbo-cavernosus. Correspondingly, as the testicles
become larger and descend into the scrotum, the V.L.C. appears to become larger as the
C.C. itself enlarges and begins to turn ventrally, taking the V.L.C. with it. The most
developed phase that was examined was that of the "transitional" male
pseudohermaphrodite in which two large testicles were situated in the scrotum and the
projection, now much longer than before, consisting of the V.L.C., the C.C. and the
terminal end of the urethra, was situated directly anterior to the scrotum. Despite all of
these varying phases of genital development, each of these animals, as an adult,
consistently exhibited tusks, with a base diameter consistent with that of the male of the
species. As expected those animals exhibiting 1 external testis (whether it appeared
normal or degenerate) also contained 1 degenerated testicle within the abdomen. In one
case, however, a young animal(Pig A) with no external testicles or scrotum, possessed only
1 small but well-formed testis inguinally. No vestige of the other testicle was detected.
In most cases, the testicles appeared to be more or less degenerate or totally so. The
vulva had a reduced urogenital aperture. There were never any rudiments of vagina, cervix,
uterus, oviduct or ovaries evident in any of the intersex pigs examined, which concurs
with Baker's findings in 1928(4).The urine was delivered from the bladder via the urethra
to the external opening anteriorly corresponding with its specific phase of
intersexuality. At the terminal end of the urethra there was a bulbo-cavernosus muscle
which aids, in normal males, in expulsion of urine or sperm. In all cases, the internal
anatomies were wholly male, although in various stages of development. Seminal vesicles,
bulbo-cavernosus muscle, and corpus cavernosus were evident in every individual.
Bulbo-urethral glands were found in all but one individual.
Descriptions of ten Malo Island pigs selected for blood and skin
biopsy examination (ages and wights are approximate).
||DESCRIPTION OF EXTERNAL GENITALIA
||Two large testicles in scrotum; VLC approx. 1.3 cm. projecting dorsally
||Black with white legs
||No testicles; scrotal sac evident; VLC approx. 1.9 cm long, pointing
ventrally; urinates just dorsal to VLC projection.
||One normal testicle and one small in scrotum; VLC approx. 1.3 cm
pointing dorsally and laterally.
||One large testicle descended in sac. VLC approx. 2.5 cm long pointing
||One small testicle in scrotum. 1.9 cm VLC projection beginning to point
||No testicles, no scrotum. Approx. 1.9 cm VLC pointing out and
||Brown and red
||One large testicle in sac 1.3 cm VLC projection.