Use of crude extract of garlic (Allium sativum) as an alternative in the prevention of saprolegniosis in rainbow trout (Oncorhynchus mykiss)

The objective of the study was to evaluate the use of garlic ( A. sativum ) in the prevention of saprolegniosis in rainbow trout ( Oncorhynchus mykiss ). Descriptive statistics were applied. We used juvenile fish distributed in 10/pond, in 15 ponds, 150 specimens (fish from 10 to 15 cm in length, with weights from 150 to 200 g), there were positive controls with symptoms of saprogneliasis and one negative individual in optimal health conditions. Once the crude garlic extract was elaborated with the determined samples, the results were: the presence of fungal structures in the form of cotton specks based on the appearance of this sign in T 1 11, T 2 13 and T 3 15 trouts respectively affected and it was analyzed during the garlic treatment the reduction and complete absence of the sign we have for T 1 22, T 2 35 and T 3 33 with frequency and representing 24 %, 39 % and 37 % respectively obtaining better results T 2 based on 500 mg of crude garlic extract. The depigmentation of the skin is another sign of Saprolegnia presence which was manifested in all fish and analyzing its reduction and absence throughout the treatment, results were obtained in T 1 and T 2 with frequencies of 59 each, representing 33.5 %, and T 3 with a frequency of 58 representing 32.9 %, the three treatments showed efficacy since there is no significant percentage difference. It is concluded that the analysis of Saprogneliasis by Saprolegnia spp. determined that T 2 (500 mg/L water/tank) was the one that controlled macroscopic lesions of Saprolegnia spp.