DEPARTMENT OF ANIMAL SCIENCE,

The study investigated the chemical composition of graded levels of chitin and chitosan, extracted from periwinkle shells, and their effects on goats dry matter intake and nutrient digestibility. Twelve (12) West African Dwarf goats were randomly assigned to six dietary treatments (control, chitin at 3% and 6%, chitosan at 0.5% and 1%, and 0.01% oxytetracycline treatments), fed alongside guinea grass at a ratio of 50:50. Chitin and chitosan were extracted using chemical processes involving demineralization, deproteinization, and deacetylation. Results showed that, dry matter digestibility (91.40–91.85%) was not significantly affected by chitin and chitosan feed additives. Inclusion of chitosan at 0.5% and chitin at 6% levels improved crude protein retention, nitrogen balance, and overall nutrient digestibility, while higher chitosan levels (1%) resulted in greater urinary nitrogen losses and reduced protein utilization efficiency. Ether extract values increased with higher chitin levels, reaching 12.00% in the 6% chitin diet, implying improved energy density. Nitrogen-free extract decreased significantly with higher chitin inclusion, indicating reduced readily available carbohydrate fractions. Organic matter content was highest (91.50%) in the 0.5% chitosan diet, suggesting improved nutrient digestibility and energy utilization. The study concludes that chitin and chitosan at 6% and 0.5% inclusion level
respectively from periwinkle shells can serve as effective feed additives for enhancing nutrient utilization in goats . This approach offers a sustainable solution for livestock nutrition while addressing environmental challenges posed by periwinkle waste in Nigeria.