Discipline: Biological Sciences
Subcategory: Plant Research
Room: Exhibit Hall
Vanessa Chery - Montgomery College
Co-Author(s): Anne Osano, Bowie State University, Bowie, MarylandJoshua Ogendo, Egerton University, Njoro, KenyaEvans Obura, Egerton University, Njoro, KenyaAnne Hilda, Egerton University, Njoro, Kenya
Tilapia is among the highest cultivated fish globally and its aquaculture is expected to expand exponentially in the coming years due to it being preferred by consumers across the globe and serving as an affordable yet rich source of protein. In Kenya and throughout Africa, tilapia aquaculture is popularly practiced by smallholder farmers, creating a sustainable livelihood while feeding their population due to its low production costs. However, the increasing cost of fish feed has driven up production cost of tilapia which in turn threatens the profitability of smallholder farmers practicing aquaculture. Traditionally, farmed fish diets are composed of commercially-sourced feeds such as fish meal. With increasing costs of commercial feeds, several research studies have been conducted with the aim of creating alternative nutrient rich, affordable, self-sourced fish feeds. Ideally, such a feed must be sourced from ingredients that are abundant and low in cost. One such substance that is dense in nutrients but has not been considered in previous scientific studies is Pennisetum purpureum, commonly known as Napier grass. Although the plant’s cellulose content has made it unavailable for use by tilapia, its digestibility in the fish can be increased while extracting essential nutrients through fungal fermentation due to the saprophytic properties of fungi. Due to the novelty of employing this approach in the tilapia farming industry, this study aimed to understand the biophysical characteristics of fungus-fermented Napier grass to guide scientists and farmers in their efforts to improve livestock productivity. We hypothesized that Napier grass supports the growth and sustenance of fungi, with the potential for transformation into tilapia feed. An experiment employing fungus-fermentation was designed and carried out where Napier grass was prepared as a substrate, transferred to a growth chamber, and inoculated with spawns of Pleurotus ostreatus. Over the course of the colonization period, internal temperatures and humidity were monitored. Results indicated that Napier grass as a substrate does support the growth of P. ostreatus as well as the growth of three competing fungal colonies. Results also demonstrated that internal temperatures were relatively low which increased risk of contamination and contributed to delayed growth rate. The biophysical characteristics of the fungus-fermented Napier grass as well as the genus and species of the competing fungi were identified, and results were used to form recommendations for scientists and farmers. It was recommended that further research be conducted to understand the toxicological effects of the three competing fungal colonies as well as developing a procedure to reduce the presence of those fungi. For farmers, it was recommended that an improved growth chamber be used to facilitate the rate of growth and reduce the risk of contamination.
Funder Acknowledgement(s): United States Department of Agriculture (USDA)National Institute of Food and Agriculture (NIFA)
Faculty Advisor: Anne Osano, firstname.lastname@example.org
Role: I started by developing hypotheses and reviewing literature. Topics reviewed included but not limited to Napier Grass, its nutritive value, fungal cultivation techniques, and nutrition in Tilapia. Simultaneously, I collaborated with my mentor to create a timeline and discuss the methodology. I visited the field to collect Napier Grass and conducted laboratory research under the guidance of our laboratory technician. Data was collected during the experiment. After the experiment, I analyzed results, formed conclusions, and made recommendations for farmers and future research for scientists.