ISSN:
1432-136X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary 1. Peak months for ecdysis are April and September (Fig. 1). Mean intermoult period of 371±118 days is reduced 56% by removal of 4–6 legs during 2 successive moulting seasons. Legs are replaced at ecdysis occurring 42 days after removal. Ecdysis occurs 84±21 days after egg laying. Laying is not a yearly event since only 40% of newly captured females laid. Eating ceases 22–34 days before ecdysis, the dorsal abdominal region darkens at 12 days, movement decreases, and a moulting bed is spun the day before ecdysis. 2. Obvious respiratory movements occur during ecdysis. Splitting of the old cuticle is due to muscular contraction and pressure from all tissues. Legs are withdrawn by muscular activity, and blood, shifted by rhythmical contractions of abdominal muscles, expands the anterior region. The abdomen which serves as a reservoir for fluid (Fig. 6), exhibits a 25% decrease in volume as a result of the shift. 3. Weights, as % of the reference weight 1 day before ecdysis, increase transiently as increased water intake and retention begin 2 months before ecdysis (Fig. 2b). Individual maximum weights of 116±3% at 33±8 days are accompanied by increases in blood volume and total water from the normal 18.8% and 73.4%, respectively, to 26.9% and 76.6%, respectively, of body weight (Fig. 7). Subsequent loss of fluid returns weights to 100% and blood and water toward normal levels by ecdysis. Weights average 91% after ecdysis. Blood volume increases transiently to 23.6% during the 10 days after ecdysis, due to loss of old cuticle and absorption of imbibed water. 4. Resorption of old cuticle reaches 61%, is greater the smaller the animal, and begins 12 days before ecdysis. New cuticle begins forming 30–40 days before ecdysis, reaches 50% of normal weight by 1 day after edysis, and 100% by 16–20 days (Fig. 8). Total blood glucose and non-glucose anthrone reactive material increase when cuticle deposition begins. Maximum concentrations, 17.3 and 16.5 mg%, respectively, occur during the 10 days before and after ecdysis, and by 20–128 days, concentrations are 2.5 and 3.3 mg%, respectively (Fig. 9). Evaporative loss of weight increases as cuticle resorption begins, reaches 50x normal during ecdysis, and is significantly above normal until 9 days afterward (Fig. 4a). 5. O2 consumption averages 0.0124 ml/g·h at 22 °C in non-moulting animals, begins to increase 30–39 days before ecdysis reaching 31/2x normal during 3 days periods before and after ecdysis, and returns to normal by 50–60 days afterward (Fig. 11). Rates increase to 9x normal during ecdysis (Fig. 13).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00735723
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