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bioRxiv · 10.1101/2024.12.23.630134

Evaluation of Three Diets Based on Dry, Live, and Wet Feeds for Optimal Growth of Discus Fish (Symphysodon p.) Under Controlled Conditions in Florencia, Caqueta, Colombia

Navarro-Morales, A.·Diaz Chaux, J. T.·Castaneda, H. C.·Ruiz-Valderrama, D. H.·Velasquez-Valencia, A.
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Abstract

This study evaluated the effect of three diets, wet (PAP), live (DAP) and commercial feed (COC), on the growth of juvenile discus fish (Symphysodon sp), under controlled environmental conditions in the Colombian Amazon. The PAP diet was made with animal protein and Amazonian fruits. The DAP diet consisted of the provision of live food (Moina macrocopa); Both diets were mixed in equal parts with the concentrate to be supplied to the fish. In the COC diet, only the commercial feed was supplied. The daily supply of each diet corresponded to 6% of the average body weight of the juveniles, adjusting the quantity in each measurement. Each treatment had four repetitions (aquarium), with a density of 0.32 individuals per liter for a total of 192 discus fish. The growth of the juveniles was monitored by taking morphometry every nine days for 63 days. The morphometric variables presented differences between the diets, the highest values were recorded in PAP and DAP. The morphometric variables such as total length and weight were positively associated with nutritional contents such as proteins, lipids and carbohydrates present in DAP and PAP. These components influenced the growth of the fish and were related to the feed conversion factor. It is suggested that fish fed with DAP and PAP continued to grow thanks to the biological and enzymatic stimuli provided by these foods, unlike the COC feeding with the lower growth reported. These results demonstrate that the combination of live foods prepared according to the habits and nutritional requirements of the species with concentrates promote the growth of the fish, promoting optimal development and general well-being of the discus fish during growth under controlled conditions.

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Navarro-Morales, A., Diaz Chaux, J. T., Castaneda, H. C., Ruiz-Valderrama, D. H., Velasquez-Valencia, A.. 2024-12-23. Evaluation of Three Diets Based on Dry, Live, and Wet Feeds for Optimal Growth of Discus Fish (Symphysodon p.) Under Controlled Conditions in Florencia, Caqueta, Colombia. https://doi.org/10.1101/2024.12.23.630134

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