Initial defecation time and rate of passage of digesta in adult Hawaiian monk seals, Monachus schauinslandi

1997 ◽  
Vol 75 (3) ◽  
pp. 433-438 ◽  
Author(s):  
Gwen D. Goodman-Lowe ◽  
Shannon Atkinson ◽  
James R. Carpenter
Keyword(s):  
Single Pulse ◽  
Base Line ◽  
Digestive Physiology ◽  
Mineral Contents ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Pulse Dose ◽  
Corn Kernels ◽  
Monk Seals ◽  
Insight Into

In an effort to gain a better understanding of the digestive physiology of the Hawaiian monk seal, Monachus schauinslandi, we measured initial defecation time and rate of passage of digesta using chromic oxide (Cr2O3) and frozen corn kernels as markers. Initial defecation time ranged from 9,5 to 19 h (mean 14 ± 4,8 h), which was a longer period of time than that reported for any other pinniped. The rate of passage of digesta measured using a single-pulse dose of Cr2O3 was approximately 39 h for two of the three seals, which is also longer than that reported for other pinnipeds. Possible reasons for these longer rates include morphological and physiological differences, age of the seals, and feeding regime. Percent Cr2O3 recovery was low (52.7–74.8%), reflecting the difficulty in collecting liquid stools. Levels of protein and ash (dry matter basis) were 21.70 and 34.79%, respectively, which reflects the high protein and mineral contents of the herring diet. This study yielded essential base-line data that will provide further insight into the digestive physiology of the Hawaiian monk seal.

Assimilation efficiency of prey in the Hawaiian monk seal (Monachus schauinslandi)

1999 ◽  
Vol 77 (4) ◽  
pp. 653-660 ◽  
Author(s):  
Gwen D Goodman-Lowe ◽  
James R Carpenter ◽  
Shannon Atkinson
Keyword(s):  
Control Diet ◽  
Assimilation Efficiency ◽  
Nitrogen Retention ◽  
Metabolizable Energy ◽  
Clupea Harengus ◽  
Digestive Efficiency ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Gross Energy ◽  
Monk Seals

Assimilation efficiency, digestive efficiency, metabolizable energy, and nitrogen retention in three captive adult male Hawaiian monk seals (Monachus schauinslandi) were measured with the indigestible marker chromic oxide for four experimental diets: a control diet of herring (Clupea harengus) and three test diets consisting of flagtail (Kuhlia sandvicensis), squid (Loligo sp.), and lobster (Panulirus marginatus), each of which was used in combination with herring. The addition of all three test prey to herring decreased the digestibility of gross energy by a mean of 3.58 ± 3.89%. Assimilation efficiency of gross energy was 96.1 ± 4.0% for herring, 73.8 ± 6.8% for flagtail, and 94.1 ± 5.7% for squid, but could not be determined for lobster. Digestive efficiency and metabolizable energy of the diets examined were high (4602.2 ± 247.1 and 4062.5 ± 178.4 kcal/d, respectively; 1 kcal = 4.18 kJ) and were positively correlated with the amount of gross energy ingested. Nitrogen retention was highest for the squid-herring diet (33.2 ± 1.2 g·d-1) followed by the lobster-herring diet (11.5 ± 3.3 g·d-1), the flagtail-herring diet (6.0 ± 0.0 g·d-1), and the herring (control) diet (-5.7 ± 1.6 g·d-1). This study indicates that prey which are both higher in protein and lower in fat than herring provide greater metabolizable energy for productive functions in Hawaiian monk seals.

Photogrammetric Estimates of Size and Mass in Hawaiian Monk Seals (Monachus schauinslandi)

2006 ◽  
Vol 32 (1) ◽  
pp. 31-40 ◽  
Author(s):  
Katherine W. McFadden ◽  
Graham A. J. Worthy ◽  
Thomas E. Lacher
Keyword(s):  
Monachus Schauinslandi ◽  
Monk Seals

Significance of wounding to female reproductive success in Hawaiian monk seals (Monachus schauinslandi) at Laysan Island

1993 ◽  
Vol 71 (3) ◽  
pp. 469-474 ◽  
Author(s):  
Lisa M. Hiruki ◽  
Ian Stirling ◽  
William G. Gilmartin ◽  
Thea C. Johanos ◽  
Brenda L. Becker
Keyword(s):  
Reproductive Success ◽  
Adult Male ◽  
Reproductive Rate ◽  
Lactation Period ◽  
Female Reproductive Success ◽  
Monachus Schauinslandi ◽  
Lower Survival Rate ◽  
Adult Females ◽  
Pup Survival ◽  
Monk Seals

We studied reproductive rate, length of lactation period, pup survival, and mortality of injured and uninjured female Hawaiian monk seals (Monachus schauinslandi) on Laysan Island, northwestern Hawaiian Islands, in 1983 – 1989. The severity and timing of nonfatal injuries were influential in determining their effect on female reproductive success. There was a tendency towards a shorter mean lactation period and lower survival rate of pups for females with major injuries than for uninjured females. Females with minor injuries were similar to uninjured females in terms of reproductive rate, length of lactation, and pup survival. For females injured shortly before the birth of their pup or during lactation, pup survival was lower than for uninjured females, whereas for females injured during the year prior to pupping, measures of reproductive success were not significantly different from those for uninjured females. Immature (aged 4 – 8 years) females entering the reproductive population were injured by adult male seals significantly more often than females aged 0 – 3 years, but at a similar rate to adult females. The major effect of injuries on female reproductive success is an increase in female mortality: 87.5 % of the adult females (n = 16) that died on Laysan Island in 1983 – 1989 sustained injuries from adult male seals.

Status of the Hawaiian monk seal (Monachus schauinslandi) population

1995 ◽  
Vol 73 (6) ◽  
pp. 1185-1190 ◽  
Author(s):  
W. G. Gilmartin ◽  
L. L. Eberhardt
Keyword(s):  
Complex System ◽  
Sex Ratios ◽  
Current Trend ◽  
Survival Rates ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Young Females ◽  
Adult Females ◽  
Unknown Factor ◽  
Adult Sex Ratio

Restoration of the Hawaiian monk seal (Monachus schauinslandi) population to its former abundance poses a number of problems in managing a complex system. Sharp differences in history and current trend exist among the six major pupping sites. A severely unbalanced adult sex ratio has resulted in deaths from "mobbing" of estrus females at two sites. Some unknown factor apparently severely reduced the numbers of females at three of the sites and thus produced the observed excess of males. Sex ratios subsequently decreased, but losses of adult females continue at two sites. A simple model indicates that sex ratios at the two sites where mobbing is a problem would require more than 10 years to approach an equilibrium value. Data on trends from counts are compared with estimates from reproduction and survival rates and agree closely except at one site (Kure Atoll), where introductions of young females have been made.

Inaktivierung von Bakterien mittels einzelner Elektronenimpulse

1960 ◽  
Vol 15 (6) ◽  
pp. 372-374 ◽  
Author(s):  
D. L. Dewey ◽  
J. W. Boag
Keyword(s):  
Dissolved Oxygen ◽  
Serratia Marcescens ◽  
Chemical Reactions ◽  
Large Dose ◽  
Single Pulse ◽  
Complete Removal ◽  
Oxygen Effect ◽  
Pulse Dose ◽  
Radiation Induced

Experiments on the inactivation of the bacterium Serratia Marcescens by radiation have shown that the normal “oxygen effect” is absent when a large dose is given in a single pulse of duration 2 μsec. This appears to be due to the complete removal of the dissolved oxygen by the early part of the pulse dose, as a result of radiation-induced chemical reactions.

scholarly journals Extremely Low Genetic Diversity in the Endangered Hawaiian Monk Seal (Monachus schauinslandi)

2008 ◽  
Vol 100 (1) ◽  
pp. 25-33 ◽  
Author(s):  
J. K. Schultz ◽  
J. D. Baker ◽  
R. J. Toonen ◽  
B. W. Bowen
Keyword(s):  
Genetic Diversity ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Low Genetic Diversity

Organochlorines in the free-ranging Hawaiian monk seal (Monachus schauinslandi) from French Frigate Shoals, North Pacific Ocean

2004 ◽  
Vol 322 (1-3) ◽  
pp. 81-93 ◽  
Author(s):  
Maia K Willcox ◽  
Lee Ann Woodward ◽  
Gina M Ylitalo ◽  
Jon Buzitis ◽  
Shannon Atkinson ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Hawaiian Monk Seal ◽  
Monachus Schauinslandi ◽  
Free Ranging

On the mechanism of action of progestins

1981 ◽  
Vol 97 (3) ◽  
pp. 320-328 ◽  
Author(s):  
Gregorio Pérez-Palacios ◽  
María A. Fernández-Aparicio ◽  
Martha Medina ◽  
Jesús Zacarías-Villareal ◽  
Alfredo Ulloa-Aguirre
Keyword(s):  
Menopausal Woman ◽  
Base Line ◽  
Continuous Administration ◽  
Post Menopausal Woman ◽  
Menopausal Women ◽  
Vaginal Rings ◽  
Differing Effect ◽  
Post Menopausal ◽  
Insight Into ◽  
Natural Progesterone

Abstract. The effect of two synthetic injectable progestins, norethisterone oenanthate3 (NET-e) and medroxyprogesterone acetate (MPA) upon the hypothalamic pituitary unit was evaluated in post-menopausal women (PMW) and in castrated individuals with androgen un-responsiveness in order to gain insight into their mechanism of gonadotrophin inhibition. Continuous administration of natural progesterone (P4) to PMW by medicated vaginal rings was used as the experimental control. Elevated base line levels of serum immunoreactive gonadotrophins and normal pituitary LRH responses were found in PMW and pseudohermaphrodites. Progesterone did not affect circulating gonadotrophin levels or the pituitary LRH response in PMW. Administration of MPA 150 mg induced a clear decrease in serum gonadotrophins and a significant decrease in LRH pituitary responsiveness in a post-menopausal woman whereas no effect was observed on serum gonadotrophins and pituitary response to LRH in a patient with androgen unresponsiveness. Administration of NET-e 200 mg resulted in a significant decrease in circulating gonadotrophins in PMW and pseudohermaphrodites, while LRH pituitary sensitivity was diminished in all subjects except one post-menopausal woman. These results demonstrated that two structurally different synthetic progestins (NET-e and MPA) had a potent gonadotrophin inhibitory activity in PMW while natural progesterone did not, thus indicating a different mode of action. Furthermore their differing effect on individuals with complete androgen unresponsiveness suggested that antigonadotrophic activity of NET-e is mediated by its oestrogenic-progestational effect, while MPA acts through its androgenic potency and therefore requires the presence of androgen receptors.

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