METHODS AND RESULTS: A total of 181 strains of Strep. agalactiae isolated from red hybrid tilapia (Oreochromis sp.) and golden pompano (Trachinotus blochii) were characterized using RAPD and REP-PCR techniques. Both the fingerprinting techniques generated reproducible band patterns, differing in the number and molecular mass amplicons. The RAPD technique displayed greater discriminatory power by its production of more complex binding pattern and divided all the strains into 13 groups, compared to 9 by REP-PCR technique. Both techniques showed the availability to differentiate the genetic profiles of the strains according to their geographical location of origin. Three strains of Strep. agalactiae that were recovered from golden pompano showed a genetic dissimilarity from the strains isolated from red hybrid tilapia, while the strain of ATCC 27956 that recovered from bovine displayed a unique profile for both methods.
CONCLUSIONS: Both techniques possess excellent discriminative capabilities and can be used as a rapid means of comparing Strep. agalactiae strains for future epidemiological investigation.
SIGNIFICANCE AND IMPACT OF THE STUDY: Framework as the guideline in traceability of this disease and in the search for potential local vaccine candidates for streptococcosis in this country.
DESIGN: A comprehensive literature review was completed. For this the electronic library databases ASFA, CABD and Scopus were systematically searched and relevant references cited in these sources were carefully analysed. The search terms used were 'fish', 'small fish species', 'micronutrients', 'food-based strategies', 'fish consumption' and 'developing countries'. The quality of data on nutritional analyses was carefully reviewed and data that lacked proper information on methods, units and samples were excluded.
RESULTS: The evidence collected confirmed the high levels of vitamin A, Fe and Zn in some of the small fish species in developing countries. These small fish are reported to be more affordable and accessible than the larger fish and other usual animal-source foods and vegetables. Evidence suggests that these locally available small fish have considerable potential as cost-effective food-based strategies to enhance micronutrient intakes or as a complementary food for undernourished children. However, the present review shows that only a few studies have been able to rigorously assess the impact of fish consumption on improved nutritional status in developing countries.
CONCLUSIONS: Further research is required in areas such as determination of fish consumption patterns of poor households, the nutritional value of local fish and other aquatic animals and the impact of fish intake on improved nutritional status in developing countries where undernutrition is a major public health problem.