Biology Reference
In-Depth Information
snake (Morocco et al., 2006). A survey conducted from January 2008 to November
2008 yielded 11 documented cases of emergency-room review of
B. irregularis
bites
on Guam (this study;
Table 4.1
). Of these, 10 consisted of minor lacerations, erythema,
and slight bleeding. One 2-week-old male reportedly exhibited respiratory distress,
thrombocytosis,
13
and required a 3-day neonatal intensive care unit (NICU) admission
(
Table 4.1
).
However, as indicated in
Table 4.1
, the major presenting symptoms in the vast
majority of victims are puncture wounds/lacerations, minor bleeding, mild edema,
ecchymoses, and mild pain. As noted above, the few cases (
n
4) that suggest
systemic signs and symptoms all involved infants. The paucity of cases from New
Guinea and Australia (only one documented case) is likely due to far less frequent
contact between humans and these snakes in their natural range. Interestingly, in
part of the natural range of
B. irregularis
, some Aboriginal clans in the Arnhemland,
Northern Territory, Australia, view
B. irregularis
as particularly dangerous to men-
struating women and those with infants (Oscar Whitehead, personal verbal commu-
nication with SAW, April 1999, and SAW personal observations). The attraction of
B. irregularis
to human menstrual blood under laboratory conditions (David Chiszar,
personal written and verbal communication with SAW, June 1993) adds some infor-
mation that supports concerns regarding the unusual allure of certain human popula-
tions to these snakes.
4.4.1.2 Overview of the Duvernoy's Gland and Associated Dentition of
B. irregularis
Boiga irregularis
has enlarged, gently recurved posterior maxillary teeth contain-
ing deep grooves that run along almost their entire length and are separated from
the anterior teeth by a diastema (
Plate 4.9E and F
). The enlarged posterior maxillary
teeth are associated with a lobular Duvernoy's gland located in the temporal region,
posterior to the maxilla (Weinstein and Kardong, 1994; Zalisko and Kardong, 1992).
The gland features lobular and common lobular ducts, a minimal central cistern (of
no appreciable secretion storage capacity), and an additional main duct (Zalisko and
Kardong, 1992).
4.4.1.3 Summary of the Properties, Toxinology, and Variability of
B. irregularis
Duvernoy's Secretion
Several investigators have reported yields of Duvernoy's secretions from
B. irregu-
laris
. Weinstein et al. (1991) reported an average liquid yield of 80.2 μL containing
6.7 mg solids with 100% protein content. Using two groups of
B. irregularis
classed
by body length, Vest et al. (1991) reported that snakes
100 cm produced an aver-
age liquid yield of 9.63 μL with 0.642 mg solids, while specimens
100 cm yielded a
liquid average 126 μL with 6.88 mg solids that contained only 22.8% protein. These
13
This pediatric patient's platelet count and hemoglobin/hematocrit with normal ranges in parentheses:
493,000↑ (150,000-350,000), 13.4/37.8 (13.3-21 g/dL/31-69%).
