Seasonal influence on the hematological parameters in cultured Nile tilapia from southern Brazil

Abstract

This study evaluated seasonality in hematological parameters of Nile tilapia cultured in the state of Santa Catarina, southern Brazil. A total of 240 fish were examined during four seasons between April 2007 and March 2008 in three different fish farms. After being anesthetised in a benzocaine solution, blood samples were withdrawn into syringes containing a drop of 10% EDTA for hematological analysis. The results were compared between fish farms and seasons, which are well delimited in southern Brazil. In a traditional fish farm in Joinville in the summer, there was an increase in the percentage of hematocrit and in the red blood cell count. The highest values of total leukocytes were found in fish from fee-fishing in Blumenau in the autumn while the lowest values occurred in those from swine consorted system in Ituporanga in the summer. Thrombocytosis was observed in the autumn, and lymphocytosis was found in both the autumn and winter in tilapia from all fish farms investigated. Neutrophilia was only observed in winter and autumn in fish from Blumenau and Ituporanga. This work demonstrated the influence of seasonality and the handling characteristics of each fish farm on certain hematological parameters in Nile tilapia.

Haematological Parameters of the Hybrid Surubim (Pseudoplatystoma reticulatum x P. corruscans) farmed in Brazil

“…The values of erythrocytes were similar to those reported in the literature for this hybrid (TavaresDias et al 2009;Mouriño et al 2012). In semiintensive ponds, higher values were observed during the warm season, as also reported by Jerônimo et al (2011), De Pedro et al (2005 and Guijarro et al (2003). Given that this season was related to lower concentrations of dissolved oxygen in the water, it could be stated that the fish increased red blood cell production to improve oxygen transport capacity, compensating for the reduced availability (Jerônimo et al 2011).…”

“…In semiintensive ponds, higher values were observed during the warm season, as also reported by Jerônimo et al (2011), De Pedro et al (2005 and Guijarro et al (2003). Given that this season was related to lower concentrations of dissolved oxygen in the water, it could be stated that the fish increased red blood cell production to improve oxygen transport capacity, compensating for the reduced availability (Jerônimo et al 2011). During the cold season, the animals of the intensive system ponds had higher erythrocyte, therefore, it was possible that in this system the concentrations of dissolved oxygen were lower, also demonstrating a compensatory effect.…”

Essential oils of Lippia sidoides and Mentha piperita against monogenean parasites and their influence on the hematology of Nile tilapia

“…Monogenean helminths are one of the most important parasites affecting fish farming and are found mainly in the gills and skin (Jerônimo et al, 2011).…”

Leukocytes respiratory burst activity as indicator of innate immunity of pacu Piaractus mesopotamicus

“…The pacu, Piaractus mesopotamicus (Holmberg, 1887) is one of the most important fish in Brazilian aquaculture (Roubach et al, 2003) and widely studied for different issues (Barreto et al, 2010;Fujimoto et al, 2010;Jerônimo et al, 2011). Its farming has grown in the last decade with an annual production around 12,400 tons (Ibama, 2005).…”