ELUCIDATION OF LOCUST AND GRASSHOPPER CONSUMPTION AND PROSPECTS OF REARING AS FOOD AND FEED IN WESTERN KENYA

Abstract

The increase in demand for the consumption of animal proteins coupled with the growing world population necessitates a re-evaluation of dietary habits. The strategies that can help increase food security include promoting edible insects as protein sources. Edible insects’ protein is comparable to or higher than the most commonly consumed animal proteins hence a good alternative protein source. The study’s main objective was to determine the knowledge and perceptions of edible grasshoppers and locust consumption in Western Kenya and the prospects of their rearing for food and feed. An experiment was carried out to investigate the growth performance of rearing locusts under laboratory and greenhouse conditions on sorghum, wheat and green gram plant diets. The growth performance of kales using decomposed locust frass was also determined. The data was analyzed using SPSS version 20 and STATGRAPHICS Centurion XVI. Of 901 respondents, 91.6% were knowledgeable about grasshopper consumption, while 8.4% had no idea. Cyrtacanthacris tatarica was most identified as edible (58.6%) while Ruspolia differens was least (1.2%) identified. Those who had never bought the insect were significantly different from those who had ever bought it (χ2 = 92.2, d.f.=1, p<0.0001). Respondents willing to rear were 50.1% which was significantly different from those who were not willing (χ2 = 13.4, d.f.=2, p=0.0012). The growth performance of desert locusts raised on different diets showed a significant difference in their growth (p<0.05). Nymphs raised on wheat in the laboratory had the highest total weight at week eight (2.48 ±0.33 g), while those raised on sorghum had the least (1.42±0.06 g). The percentage survival rate was high in nymphs raised on wheat both at the greenhouse (96.56%) and laboratory (90.31%), but lowest in nymphs raised on sorghum (76.41%). The nymphs raised on sorghum in the laboratory took the longest time (54.29) days to complete their development while nymphs raised on wheat took the shortest time in the laboratory (37.49) days and greenhouse (36.56) days. Desert locusts raised on a green gram diet had high amounts of protein (48.14±0.6), fat (36.08±0.2), and crude fiber (12.89±0.6) compared to desert locusts raised on other diets. The growth of kales planted with decomposed locust frass was comparable to kales planted with chicken manure in terms of the height of the plant, number of leaves and chlorophyll content. The growth performance of kales planted in plain soil performed poorly. The results show that the respondents of western Kenya were more knowledgeable about grasshopper and locust consumption and were willing to rear them for food and feed. Desert locusts can be reared under greenhouse conditions on a small scale and wheat and green gram plant diets can be used as feed substrate. Furthermore, locust frass has the potential to be used as an organic manure.