CRESCIMENTO COMPENSATÓRIO DO CAMARÃO-BRANCO Litopenaeus vannamei (Boone, 1931) NO EXTREMO SUL DO BRASIL.
The present work evaluated the occurrence of compensatory growth of the white shrimp Litopenaeus vannamei submitted to long nursery culture period at high stocking density and exposed to winter and early spring low temperatures, in Southern Brazil. Shrimp were reared in two different culture systems: the treatment denominated ?compensatory" growth (CC) evaluate the growout performance of shrimp nursed during 145 days at density of 2000 shrimp/m2 during winter season in a 20m² nursery tank without heating system; in the control treatment, here denominated ?normal growth? (CN) shrimp were reared in an identical nursery tank at the same density, but for a period of 16 days during late spring, when temperature is warmer. Shrimp survival and mean weight after nursery period was respectively 79.7% and 0.64?0.31g for treatment CC and of 93% and 0.360.09g for treatment CN. Shrimp were then transferred to four lined growout ponds (two replicates per treatment) and reared during 101 days until harvest. During growout, about every 18 days, fifty shrimp were randomly sampled from each pond and their wet weight was individually measured to the nearest 0.01g. At harvest, final biomass from each pond was measured and 100 shrimp from each pond was individually weighted to determined mean final weight and estimate survival. Additionally, specific growth rate (SGR), weekly growth rate (WGR) and weekly percent growth (WPC) was calculated from each replicate pond. Statistical analysis of the collected data was performed using t-test (p<0.05). Results showed that shrimp reared in the treatment CC achieved a significantly higher mean final weight (p<0.05) than shrimp from the control treatment CN. The SGR at the beginning (first two and a half weeks) of the experiment was also significantly higher for shrimp reared in the CC treatment; afterwards, shrimp from the control treatment had a higher SGR. The results of the experiment clearly demonstrated that shrimp reared for a longer nursery period at high densities and exposed to lower temperatures showed a compensatory growth during the beginning of the growout phase. These results can help management practices employed in shrimp farms through better use of facilities.
Advisor:Wilson Francisco Britto Wasielesky Junior; Silvio Ricardo Maurano Peixoto; Mario Roberto Chim Figueiredo
School:Fundação Universidade Federal do Rio Grande
Source Type:Master's Thesis
Date of Publication:02/28/2008