Evaluation of three feeding practices on the winter culture of yellowleg shrimp, Penaeus californiensis (Holmes), in low water exchange ponds

Three different feeding practices, feeding tables (FTAs), feeding trays (FTs) and complementation of natural food (CNF), for the culture of yellowleg shrimp, Penaeus californiensis (Holmes), were evaluated in an experimental study conducted for 23 weeks in the winter season in Bahia Kino, Sonora, Mexico. Significant differences in growth, yield and feed conversion ratio were observed among treatments. The best individual weight gain (10.05 g) was obtained in the CNF treatment, followed by the FT (8.03 g) and FTA treatments (6.02 g). The mean survivals in the FT, CNF and FTA treatments were 56.3%, 60.4% and 62.6%, respectively. Yield was greatest in the CNF treatment, with a mean of 1415 kg ha^-1. The FT and FTA treatments had mean yields of 1212 and 1130 kg ha^-1, respectively. Feed conversion ratio was significantly better (P < 0.05) in the CNF (2.1:1) and FT treatments (2.3:1) than in the FTA treatment (2.9:1). Total food supply was greater in the FTA treatment (3288.3 kg ha^-1) than in the CNF (3028.1 kg ha^-1) and FT treatments (2811.8 kg ha^-1). Significant differences in some of the water-quality parameters, such as morning dissolved oxygen, ammonia, biochemical oxygen demand, and organic matter in water and sediment, were observed between treatments. The FTA treatment showed the poorest water quality.