ABSTRACT: The pathogenicity of shell lesions in Haliotis iris Martyn was examined in a laboratory experiment in which 73 apparently healthy and 106 lesion-bearing abalone were maintained for up to 12 mo. The abalone were collected from the wild and kept in cages (1 ind. cage-1) for 4, 8 or 12 mo, at which times estimates of survival, growth, condition and reproductive capacity were made for each of 3 groups: Œhealthy¹ (n = 73), Œmildly affected¹ (n = 61) and Œseverely affected¹ (n = 32). Unaffected abalone showed a 2.7% mortality (n = 73) compared to 7.5% (n = 93) in lesion-bearing individuals over the entire experiment. Growth rates were significantly decreased in mildly and severely affected abalone: the relative von Bertalanffy growth coefficient (K), calculated over 12 mo, was -0.176 for unaffected, -0.079 for mildly affected and -0.048 for severely affected individuals. The asymptotic length (L∞) was calculated to be 131.5 mm for unaffected, 142.1 mm for mild affected and 150.3 mm for severely affected abalone. Significantly (p < 0.05) lower condition indices and decreased reproductive capacity (p > 0.05) were obtained for the severely affected group compared to unaffected abalone. These trends were consistent over the course of the experiment.
KEY WORDS: Abalone · Haliotis · Gastropoda · Shell lesion · Mortality · Growth · Condition · Reproductive capacity
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