RELATIONSHIP OF MORPHOLOGICAL INDEXES AND WATER QUALITY IN WILD Lutjanus colorado FOR MATURITY IN CAPTIVITY

In the north of the Sinaloa coast, the red snapper, Lutjanus colorado, is considered one of the most important fish species because of its commercial and nutritional value. 206 organisms were stacked during the four seasons (winter, spring, summer and autumn) of 2016, from the Sinaloa coast, the blood samples of 1.5 ml were extracted from each fish. The following biochemical parameters in blood were analyzed: The gastric repletion index (GI), gonadosomatic index (GI), hepatic index, and condition factor (K) were obtained. Water physicochemical parameters such as temperature (°C), salinity (ppm), dissolved oxygen (OD), hydrogen potential (pH), nitrites (NO2), nitrates (NO3), ammonium (NH4) and phosphates (PO4) were also determined. The values of blood samples from wild red snapper were correlated with fish size and season. Fish body weight and total length (LT) ranged from 81.3 to 2,040 g, and from 17.5 to 52.7 cm, respectively. The IRG (3.16 ± 0.25) and K (1.27 ± 0.01 %) indexes were higher in summer, whereas the higher GI and HI values were obtained in autumn, with averages of 0.11 ± 0.01 and 1.8 ± 0.12 %, respectively. For The environmental variables showed fluctuations during each of the seasons. The temperature, dissolved oxygen, salinity, pH, nitrites and nitrates showed significant difference (P≤0.05) during the seasons, ammonia and phosphates did not present significant difference (P≥0.05). The results contribute to better understand on the reproductive physiology of the red snapper from the wild, and the development of its culture in captivity.