Effects of temperature on gut‐loading and gut‐clearing times of the burrowing mayfly, Hexagenia limbata
1978; Wiley; Volume: 8; Issue: 3 Linguagem: Inglês
10.1111/j.1365-2427.1978.tb01447.x
ISSN1365-2427
AutoresMelvin C. Zimmerman, Thomas E. Wissing,
Tópico(s)Aquaculture Nutrition and Growth
ResumoSUMMARY. The effect of temperature on gut‐loading times, gut‐clearing times, and the calculated ingestion rates, egestion rates, and consumption indices of the deposit‐feeding burrowing mayfly, Hexagenia limbata , were investigated in laboratory experiments. Rates of movement of two natural sediments of differing colour through the digestive tract were monitored to quantify feeding intensity when ambient water temperatures approached 5, 10, 15, 20, and 25°C. At each temperature, gut‐loading times (GLT) and gut‐clearing times (GCT) increased as nymph length increased. Mean GLT and GCT values decreased as temperature increased from 5 to 20°C but were longer at 25°C than at 20°C. Relationships between GLT, GCT, and length of nymphs and temperature were best described by multiple regression equations. No diel variation in gutclearing times was observed. Low water temperatures resulted in lower ingestion and egestion rates and consumption indices. At most temperatures nymphs ingested over 100% of their dry body weights per day.
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