Gd. Goodmanlowe et al., INITIAL DEFECATION TIME AND RATE OF PASSAGE OF DIGESTA IN ADULT HAWAIIAN MONK SEALS, MONACHUS-SCHAUINSLANDI, Canadian journal of zoology, 75(3), 1997, pp. 433-438
In an effort to gain a better understanding of the digestive physiolog
y of the Hawaiian monk seal, Monachus schauinslandi, we measured initi
al defecation time and rate of passage of digesta using chromic oxide
(Cr2O3) and frozen corn kernels as markers. Initial defecation time ra
nged from 9,5 to 19 h (mean 14 +/- 4,8 h), which was a longer period o
f time than that reported for any other pinniped. The rate of passage
of digesta measured using a single-pulse dose of Cr2O3 was approximate
ly 39 h for two of the three seals, which is also longer than that rep
orted for other pinnipeds. Possible reasons for these longer rates inc
lude morphological and physiological differences, age of the seals, an
d feeding regime. Percent Cr2O3 recovery was low (52.7-74.8%), reflect
ing the difficulty in collecting liquid stools. Levels of protein and
ash (dry matter basis) were 21.70 and 34.79%, respectively, which refl
ects the high protein and mineral contents of the herring diet. This s
tudy yielded essential base-line data that will provide further insigh
t into the digestive physiology of the Hawaiian monk seal.