arrow_rtl    arrowsig

Rev. biol. mar. oceanogr. 51(1): 61-67


Intensive culture system of Litopenaeus vannamei in commercial ponds with zero water exchange and addition of molasses and probiotics 

This email address is being protected from spambots. You need JavaScript enabled to view it.1, George Alves Modesto1, Luis Otavio Brito2, Alfredo Olivera Galvez2 and Tereza Cristina Vasconcelos Gesteira3

1Aquarium Aquicultura, Varzea da Ema s/n, Zona Rural, Mossoró, RN, Caixa Postal: 05, Brazil
2Departamento de Pesca e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manoel de Medeiros, Dois Irmão, 52171-900, Recife, PE, Brazil 
3Centro de Diagnóstico de Enfermidades de Organismos Aquáticos, Instituto de Ciências do Mar, Universidade Federal do Ceará, Avenida da Universidade, 2853, Benfica, Fortaleza, CEP: 60020-181, Brazil

emailButton  This email address is being protected from spambots. You need JavaScript enabled to view it.

The southwestern Gulf of California has high-value commercial fisheries; however, there are few studies of the taxonomic diversity of fish in this area. Surveys of taxonomic diversity of the fish assemblage at 8 localities near the shore of Bahía de La Paz were undertaken from March 2002 to April 2003. Seasonal changes in diversity of rocky reef fish were analyzed, including taxonomic distance among fish species, using the alpha, alpha average, beta, and gamma diversity indices, the taxonomic distinctness index (TD D*), and the average taxonomic distinctness index (AvTD D+). Submarine visual censuses were carried out along 48 transects measuring 100 × 5 m (500 m2) at 5 m average depth from 09:00-16:00 h. Two seasons were studied: winter with an average temperature of 22.57°C, and summer with an average temperature of 27.09°C. 24,633 fishes, belonging to 92 species and 67 genera were recorded. According to the alpha average, beta, and gamma diversity indices, August had the highest diversity (19.5, 40.5, and 60 species, respectively), and December had the lowest diversity (20.6, 27.4, and 48 species, respectively). Spatial analysis of TD and AvTD were not significantly different, and analysis by season of these indices was not significant different. Greater anthropogenic impact would cause differences in TD and AvTD found at El Guano compared with other locations.
A 16-week trial was carried out to evaluate an intensive culture system of Litopenaeus vannamei in commercial ponds with zero water exchange. Two management strategies were used:  one with the addition of molasses (ML) and the second with commercial probiotic and molasses (PML), each with four replicates. Shrimp L. vannamei (2.09 ± 0.3 g) were stocked in 2.6 ha ponds without liners at a density of 98 shrimp m-2. The commercial probiotics used with molasses was a mixture of Bacillus spp. and Lactobacillus sp. After 16 weeks, no significant differences were found in mean dissolved oxygen, temperature, salinity, pH, total heterotrophic bacteria and zootechnical parameters (yield, FCR, survival and final weight) between the two management strategies. Total ammonia nitrogen concentration (53 to 69%) was the highest inorganic nitrogen compound. There were no significant differences between its concentrations in the two management strategies. The addition of molasses and probiotics are important management strategies for increased shrimp growth in an intensive system in ponds with zero water exchange, however, molasses is cheaper than the probiotics. Molasses inputs were based on a percentage of the daily feed allotments (by weight) and application rates of 30% of total daily feed in combination with commercial probiotics in intensive ponds without liners with zero water exchange was not sufficient to recycle all nitrogen waste with 10 HP ha-1.

Key words:  Molasses, probiotics, total heterotrophic bacteria, zootechnical parameters