In order to study the function of kinesin-14 motor protein KIFC1 during spermatogenesis of Procambarus clarkii, the full length of kifc1 was cloned from testes cDNA using Rapid-Amplification of cDNA Ends (RACE). The deduced KIFC1 protein sequence showed the highest similarity between Procambarus clarkii and Eriocheir senensis (similarity rate as 64%). According to the results of in situ hybridi...

Nociceptors are sensory neurons that are tuned to tissue damage. In many species, nociceptors are often stimulated by noxious extreme temperatures and by chemical agonists that do not damage tissue (e.g., capsaicin and isothiocyanate). We test whether crustaceans have nociceptors by examining nociceptive behaviours and neurophysiological responses to extreme temperatures and potentially nocigen...

The formation of social dominance hierarchies was studied in groups of five juvenile crayfish, 1.3-1.8 cm in length. Animals were grouped together in a small, featureless aquarium after having lived in isolation for more than a month. The occurrence of each of four behavior patterns ('attack', 'approach', 'retreat' and 'escape') was recorded for each animal, together with the frequency of encou...

Although native to the southeastern United States, the red swamp crayfish (Procambarus clarkii) has become established worldwide through accidental and intentional actions by humans. In the Santa Monica Mountains of southern California, the presence of the omnivorous crayfish is associated with the absence or reduced abundance of native amphibians. The original source of P. clarkii in southern ...

This study examined the effects of an acoustic stimulus on the haemolymph and agonistic behaviour of the red swamp crayfish, Procambarus clarkii. The experiment was conducted in a tank equipped with a video recording system using six groups (three control and three test groups) of five adult crayfish (30 specimens in total). After 1 h of habituation, the behaviour of the crayfish was monitored ...

Red crayfish, Procambarus clarkii, is widely farmed in the southern states of Louisiana and Texas. It is the most valuable of commercial crayfish species in the United States, where it is considered a delicacy. In recent years, its availability has decreased due to environmental contamination by toxic chemicals including lead. In the present study, we conducted a ninety-six-hour static renewal ...

We tested the hypothesis that polarization sensitivity enhances the detection of moving, transparent objects by examining the escape response of the red swamp crayfish (Procambarus clarkii Girard) from a visual threat. A transparent, birefringent target trans-illuminated by either partially linear polarized or unpolarized light was advanced toward individual crayfish. The optical axis of the ta...

In 1997, an outbreak of human tularemia associated with hare-hunting in central Spain affected 585 patients. We describe the identification of Francisella tularensis biovar palaearctica in a second outbreak of ulceroglandular tularemia associated with crayfish (Procambarus clarkii) fishing in a contaminated freshwater stream distant from the hare-associated outbreak. The second outbreak occurre...

The sperm of the crayfish, Procambarus clarkii, is relatively simple among decapod sperm and was described in the first paper of this series (28). The present paper details the development of this sperm as followed with the light and electron microscopes. The process is divided into six stages for purposes of description. The main points of interest discussed are the absence of mitochondria or ...