Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: 9/1/2011
Publication Date: N/A
Technical Abstract: Superior performance of channel x blue hybrid catfish in production ponds coupled with consistent availability of fingerlings to food fish farmers have made hybrid catfish a most desired aquaculture species for production in the catfish industry. Projected hybrid fingerling production in 2011 is expected to reach 100 million. However, consistent hybrid fry production in catfish hatcheries is still a major limitation to more widespread use of hybrids. There is a need to reduce the cost of hybrid embryo production by developing suitable hormone induction protocols to make the industry sustainable and profitable. The objective of the study was to assess the effectiveness of common carp pituitary extract (CPE), luteinizing hormone releasing hormone (LHRHa) alone or in combination for inducing ovulation in channel catfish females in hybrid fry production. The following hormone treatments (n=10) were evaluated in a spawning trial: priming dose – C1: 2mg CPE/Kg BW or L1: 20 ug LHRHa /Kg BW and a resolving dose 15h later either C2: 8mg CPE/kg BW or L2 : 80 ug LHRHa /kg BW; control group received 0.85% saline. All females ovulated in treatment group and none in the control group (Table 1). Hatch and Latency were higher in LHRHa group compared to CPE. All other parameters assessed were similar. Ovulation was more synchronized with CPE than LHRHa (Figure 1). Maturation profiles of oocytes and plasma estradiol assessed at 30 h post first injection will also be presented and possible physiological processes that explain the improvement in hatching success will be discussed.