Comparison of Selected Condition Indices Between Intermolt and Post-Molt Marron, Cherax tenuimanus, of Different Feeding Status Raised Under Intensive Culture Conditions

ABSTRACT

Mature marron, Cherax tenuimanus (mean weight 40.2 ± 2.3 g), were raised in an intensive system to investigate changes in hepato-pancreatic and tail muscle indices and total hemocyte counts in fed intermolt (stage C) and either fed or non-fed post-molt (stage AB) groups. Marron were raised in individual compartments in a recirculating system under controlled environment. Wet and dry somatic indices, tissue moisture of hepatopancreas and tail muscle, and total hemocyte counts were analyzed in 10 marron in each group. The results showed no differences in hepatopancreatic indices between intermolt or post-molt fed marron, while food deprivation resulted in marron having smaller hepatopancreata with higher moisture content. Furthermore, fed intermolt marron had smaller tail muscle with lower moisture content compared to fed post-molt marron. Food deprivation resulted in non-fed post-molt group having high muscle moisture content. The wet muscle index in non-fed post-molt group was comparable to that of the fed pre-molt group, while dry muscle index was comparable to that of the fed post-molt group. The total hemocyte counts were similar among all studied groups. It was concluded that molt stage affects the tail muscle indices and that the assessment of marron condition could be based on hepatopancreatic or tail muscle indices.

Key Words:

• Cherax tenuimanus
• feeding
• body indices