Assessment of nutritional profile of ensiled guava leaves (Psidium guajava l.) as off-season feed for ruminants in the tropics

Abstract

This research aimed to investigate the nutritional potential of ensiled guava leaves (Psidium guajava L.) as an alternative livestock feed during the off- season in the tropics- a period characterised by scarce and low- quality forage, which has resulted in poor animal performance, particularly in ruminants. Three studies were conducted. The first study involved ensiling guava leaves with different additives: groundnut cake (GLGNC), palm kernel cake (GLPKC), and without additives (GLNAD). The second study determined the chemical composition of ensiled guava leaves, while the third assessed the in vitro gas production parameters and characteristics of ensiled guava leaves over a 24- hour incubation period to predict the metabolizable energy (ME), organic matter digestibility (OMD), short- chain fatty acids (SCFA), soluble degradable fraction (a), insoluble degradable fraction, potential degradability (a + b), and rate of degradation (c). The results revealed that temperature and pH values ranged from 29. 0 to 30.0. 0 ° C and 4. 4.2 to 5. 5.0 for GLGNC and GLNAD, respectively. The physical qualities of all silages were firm, pleasant, and adequate. Significant differences were observed in the proximate composition; dry matter was highest (87. 03%) in GLNAD. Crude protein levels were highest (22. 34%) in GLGNC and lowest (18. 13%) in GLNAD. The highest (48. 32%) values for Neutral Detergent Fibre (NDF) were recorded in GLNAD, while the lowest (41.63. 63%) values were recorded for GLGNC. All macro and micro minerals examined were similar. Metabolizable Energy (ME), Organic Matter Digestibility (OMD), and Short Chain Fatty Acids (SCFA) values ranged from 3. 30 to 4. 70 MJ/Kg DM, 37. 74% to 43. 53%, and 0. 14 to 0. 0.22 mmol in GLNAD and GLGNC, respectively. The same trend was observed for a, b, a + b, and c fractions, ranging from 3. 10 to 4. 73 ml/200mg DM, 13. 00 to 18. 56 mL/200mg DM, 16. 10 to 23. 29 mL/200mg DM, and 0. 10 to 0. 21 ml/hr in GLNAD and GLGNC, respectively. Total gas produced was highest (17. 87 mL/200mg DM) in GLGNC and lowest (12. 83 mL/200mg DM) in GLNAD. The volume of methane gas produced was highest (4. 33 ml/200mg DM) in GLGNC and lowest (2. 42 mL/200mg DM) in GLNAD. It can be concluded that ensiled guava leaves with groundnut cake (GLGNC) demonstrated better potential as an alternative resource for ruminants, particularly during the dry season.