Dataset on the production of predominantly male tilapia progeny using two malawian tilapias, Oreochromis karongae and Oreochromis shiranus .

A dataset is presented of an experiment that was conducted to compare the proportions of males obtained from hormonal sex reversed pure strain of Oreochromis shiranus and from interspecific hybridization of O.karongae male x O. shiranus female. Part of the data in the dataset were published in a journal article https://doi.org/10.1016/j.aqrep.2020.100274. The data were generated from four SETs of treatments of an experiment that was conducted at the National Aquaculture Center, in Malawi. The first SET of treatment comprised hybrids from interspecific crossing of O.karongae male and O. shiranus female in a pond based breeding hapa 1. SETs 2 and 4 were for fry from hapa spawned pure cross of O.shiranus males and females in a pond based breeding hapa 2. SET 3 comprised fry from pure cross of O. shiranus males and females under controlled temperature (27°C) in an indoor re-circulatory hatchery (Tables 1 to 4). During the first part of the experiment, the fry was raised for 28 days in tanks at three replicates and was fed a fry formulated feed containing 38% crude protein, three times a day. However, for SETs 2 and 3, the feed contained 17α-methyl testosterone at 60mg/kg of feed. The second part of the experiment involved growth performance testing of fry in each SET. The growth experiment was conducted in rearing hapas that were inserted in a common pond for a period of 70 days. The body weight data were collected every 14 days (Tables 1 to 4). On the 70th day, the proportions of males and females in the four SETs was determined using Aceto-carmine staining method (Table 5). The pictures of the stained male and female gonads under compound microscope are presented in the published journal article at https://doi.org/10.1016/j.aqrep.2020.100274. Dataset presented in this paper is for body weights of fish from day 0 to day 70 and proportion of males and females in each SET on the 70th day of the experiment (Tables 1, 2, 3, 4 and 5). The data were analyzed using SPSS version 20.0. Chi-square goodness of fit test was used to investigate if the observed sex ratios significantly deviated from the expected sex ratios at 5% level of significance. The differences among fish body weights were determined using Analysis of Variance and significantly different means were separated using Duncan's multiple range test at the 5% test level of significance. These data are useful for various stakeholders that are interested in sexing juvenile tilapia and for scientists that conduct tilapia sex reversal experiments. This data can also guide hatchery managers during commercial production of all male tilapias which grow faster than those in the mixed sex tilapia culture.