Leech Biology and Behaviour
نویسنده
چکیده
Hirudo medicinalis has virtually an obligatory symbiotic relationship with the bacterium Aeromonas hydrophila (= Pseudomonas hirudinis), the only species of bacteria which lives in its gut (Zirpolo 1923; Lehmensick 1941, 1942; Hornbostel 1941; Büsing 1951; Büsing et al. 1953; Wilde 1976; Jennings and Van der Lande 1967; Whitlock, O'Hare, Saunders and Morrow 1983). Aeromonas hydrophila is important in the life of H. medicinalis in several respects.
منابع مشابه
On the termination of ingestive behaviour by the medicinal leech.
Hungry leeches, Hirudo medicinalis, ingest blood meals averaging 890% of their mass in 29 min. Ingestion is terminated as a result of distension of the body: experimentally distending leeches as they feed causes an immediate cessation of ingestion and inhibits any subsequent biting behaviour; if distension is circumvented by various experimental procedures, leech ingestive periods are prolonged...
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During the consummatory phase of feeding, in which blood is ingested, medicinal leeches display a characteristic set of behaviours: they extend their jaws, are less responsive to sensory input, produce mucus, relax the body wall and exhibit waves of peristalsis that can run the length of the body. Earlier reports suggested that this pattern of behaviour is orchestrated by serotonin released fro...
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The body wall muscles of sanguivorous leeches power mechanically diverse behaviours: suction feeding, crawling and swimming. These require longitudinal muscle to exert force over an extremely large length range, from 145 to 46 per cent of the mean segmental swimming length. Previous data, however, suggest that leech body wall muscle has limited capacity for force production when elongated. Sero...
متن کاملFunctions of the subesophageal ganglion in the medicinal leech revealed by ablation of neuromeres in embryos.
Two general trends in the evolution of the nervous system have been toward centralization of neuronal somata and cephalization of the central nervous system (CNS). These organizational trends are apparent in the nervous system of annelid worms, including leeches. To determine if the anterior brain of the leech serves functions similar to those of the brains of more complex organisms, including ...
متن کاملIngestive behaviour and physiology of the medicinal leech.
Ingestion lasts 25 min in Hirudo medicinalis and is characterized by pharyngeal peristalsis which fills the crop. This peristalsis has an initial rate of 2.4 Hz which decays smoothly to 1.2 Hz at termination of ingestion. During ingestion, the leech body wall undergoes peristalsis which appears to aid in filling the crop diverticula. Body peristalsis begins at a rate of 10 min-1 and decreases l...
متن کاملPatterns of activity and the effects of activation of the fast conducting system on the behaviour of unrestrained leeches.
1. The neural activity of the nerve cord of Hirudo medicinalis has been recorded in unrestrained animals by means of chronically implanted electrodes. 2. The Fast Conducting System (FCS) is inactive both in motionless animals and during various kinds of active behaviour (creeping, swimming, ventilation). 3. Photic and tactile stimuli applied to a motionless animal elicit a FCS discharge, which ...
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