Effect of Pouteria sapota kernel meal on in vitro ruminal fermentation, nutrient degradability, and protozoa population

Resumen

This study determined the effect of different levels of mamey kernel meal (MKM) as a substitute for ground corn and soybean meal on in vitro gas production, nutrient degradability, fermentation, and protozoan population. The study was carried out in a randomized block design repeated over time. The treatments consisted of seven levels of mamey kernel meal, namely 0, 5, 10, 15, 20, 25, and 30% dry matter (DM), replacing ground corn and soybean meal. The inclusion of MKM had a linear effect on in vitro gas production (P=0.03); the highest production was at 30% inclusion and the lowest at 0%, with 381 and 291 mL g^-1, respectively. No differences (P>0.05) were found in gas production, fermentation rate, and lag time between treatments. The maximum volume of gas production (397.43 mL g^-1) was at 30%, while the lowest (291.40 mL g^-1) was observed at 0% inclusion of MKM. No differences were found in nutrient degradability, protozoan population, and volatile fatty acids (P>0.05). The genera of protozoa that were identified were Entodinium and Holotrich. The different inclusion levels of MKM did not affect the total protozoa population (P>0.05). In conclusion, MKM can be included up to 15% under in vitro conditions without negative effects on fermentative parameters. However, further in vivo studies are needed.