Handling stress in rearing farms of bullfrog, Lithobates catesbeianus, during metamorphosis: biochemical, hematological and morphological aspects

• Grant number: 09/16444-0
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2010
• End date: January 31, 2012
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal Investigator: Cláudia Maris Ferreira Mostério
• Grantee: Cláudia Maris Ferreira Mostério
• Host Institution: Instituto de Pesca. Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Rearing healthy tadpoles and froglets is an imperative step for a successful bullfrog management. In this commercial activity the stress is of concern as a critical window for many other diseases. The stress may be the induced by several causes such as: inappropriate rearing systems; inadequate physical, prophylactic and fed procedures; or by the physical and chemical properties of the water. The main glycocorticoid to be involved in the stress response is the corticosterone. This hormone has influence on the reproductive behavior, food ingestion; and locomotion, escape and fight activities. On the other hand, the excess of glycocorticoid reduces the growth and the immune defense, leading to huge animal lost. From metamorphosis up to the 30 subsequent days encompass the most critical period for high mortality incidence in commercial frog farms. This work aims to evaluate the physiological response of the stress during the metamorphosis climax of bullfrogs (Lithobates catesbeianus) submitted to different animal stock densities and to selective handling by animal size. Two identical experimental designs will be performed either in laboratory or in field. In the first experiment four different densities for animal were tested: Treatment 1 (70 animals/m2), Treatament 2 - Control (100 animals/m2), Treatament 3 (150 animals/m2) and Treatament 4 (200 animals/m2), using 3 simultaneous replicates. The second experiment will test 3 selective handling by animal size: Treatament 1 - Control (without selective handling), Treatament 2 (with partial selective handling each 15 days), Treatament 3 (with total selective handling each 15 days), using 4 simultaneous replicates. For the stress response evaluation biochemical parameters for plasmatic corticosterone (radio immune assay) and for glycemy (spectrophotometry) will be quantified. In addition, hematological parameters in red and white blood cells, and the morphology of cromafins cells (kidneys) and mucus cells (epiderm) will be determined. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GRADISSE FREITAS, JORGINA JULIANA; VIAU, PRISCILA; OLIVIERA, CLAUDIO ALVARENGA; TEIXEIRA, PATRICIA COELHO; TACHIBANA, LEONARDO; DIAS, DANIELLE DE CARLA; HIPOLITO, MARCIO; BORDON, ISABELLA CRISTINA C.; ALFAIA, STHEFANY ROSA; FERREIRA, CLAUDIA MARIS. Effect of dietary supplements in American bullfrogs reared in low and high stocking densities. AQUACULTURE REPORTS, v. 8, p. 45-48, NOV 2017. (09/16444-0)