International Journal of Aquaculture, 2025, Vol.15, No.3, 135-148 http://www.aquapublisher.com/index.php/ija 139 carry out cage farming of tilapia, with an annual output of hundreds of thousands of tons. In the future, it has the potential for replication and promotion in a wider inland waters. 3.3 Prediction and regulation strategies for future distribution by climate model In order to quantitatively predict the changes in the potential adaptive range of tilapia under climate change scenarios, the researchers used species distribution models and climate model data for analysis. Simulation results generally show that by around 2050, the total area of suitable tilapia farming areas around the world will expand, and the center of high-suitability areas will be shifted. China's model forecast points out that the area of high-risk invasion areas will increase in the future, and the center will move from south China to north China (Esmaeili and Barzoki, 2023). Rising temperatures and changes in precipitation patterns in winter are considered to be the main climate factors driving this trend. On a global scale, some currently marginalized warm temperate areas or seasonal suitable areas may become suitable areas throughout the year after warming. However, some studies have also emphasized that the impact of extreme climate events on future distribution of tilapia should be considered. For example, an increase in climate variability may lead to abnormal cold waves in some years, which will hit the northern margin breeding areas. To this end, adaptive strategies need to be followed up simultaneously. First, breeding units can adopt wintering guarantee measures, such as building temperature-controlled greenhouses and hot spring water heating in high-latitude areas to cope with occasional low temperatures and safely push the tilapia breeding scope to the marginal area. Secondly, varieties should be actively selected and breeded to cultivate corresponding stress-resistant strains based on the climatic characteristics of different regions. Improve the breeding risk warning system and use meteorological forecasts to guide farmers to prevent extreme weather in a timely manner. 4 Genetic Improvement Promotes Variety Optimization 4.1 Breeding and genotype analysis of high growth lines Genetic breeding plays a central role in the development of the tilapia breeding industry. One of the most representative results is the cultivation of the "GIFT tilapia" line. In the late 1980s, WorldFish, in conjunction with scientific research institutions in many countries, successfully cultivated GIFT tilapia with significantly improved growth rates by collecting wild populations of Nile tilapia from many places in Africa, and applying family breeding and index selection methods. After multiple generations of breeding, the growth rate of GIFT tilapia has increased by about 85% to 100% compared with the basic population, and the bait conversion efficiency and survival rate have also been significantly improved (Bentsen et al., 2017). In recent years, with the development of molecular genetic technology, genotype analysis of tilapia growth traits has made in-depth progress (Liang et al., 2024). Genome-wide association analysis (GWAS) and genome-wide selection (GS) are used to discover key QTL sites that affect growth, thereby accelerating the genetic improvement process. For example, Yáñez et al. (2020) reported progress in genome selection research on traits such as tilapia growth and disease resistance, demonstrating that using genome breeding value (GEBV) selection can achieve a genetic gain of 5% to 10% per generation (Yáñez et al., 2020). Multi-trait selection is also one of the directions for breeding of strains. In a Mexico trial, a comprehensive evaluation of growth, survival and feed utilization was performed on several new lines, and the results showed that some new lines such as "Silver YY" grew fast but had slightly lower survival, while GIFT showed a balanced performance in various traits. This suggests that different traits need to be weighed during breeding. 4.2 Selection of molecular markers related to improving disease resistance The intensification of tilapia farming has made the disease problem increasingly prominent, and traditional drug and vaccine measures have limited effect in large-scale farming. Therefore, improving the disease resistance of tilapia through genetic improvement has become one of the important solutions. In recent years, breakthroughs have been made in the research on disease-resistant breeding of major diseases of tilapia (such as streptococcosis, tilapia lake virus, etc.). On the one hand, family breeding has been used to screen disease-resistant strains (Joshi et al., 2020). On the other hand, molecular marker assisted breeding provides tools for rapid improvement of disease resistance. Through genome-wide association analysis, researchers found the main-effect QTL sites related to
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