Sustainable intensification of rabbit production necessitates the exploration of non-conventional
feed resources to mitigate the rising costs and limited availability of conventional ingredients.
The present study evaluated the effects of dietary inclusion of dried guava pomace (DGP), alone
or combined with a prebiotic source of mannan-oligosaccharides and β-glucan or an organic acid
blend, on growth performance, selected hemato-biochemical parameters, cecal histomorphology
and some growth and immune-related gene expression in healthy New Zealand White growing,
28-day old, male rabbits. Compared with the control diet, the DGP-based diet presented significant
improvements in final weight, final weight gain, feed intake, and feed conversion ratio as well as
performance index (P < 0.01). Furthermore, fortification of diets with an organic acid blend plus DGP
improved selected hematological indices, with no signs of liver or kidney impairment. Examination
of cecal histomorphology showed increased villus height and preserved mucosal integrity in rabbits
fed DGP-based diets. Gene expression analysis revealed increased muscle insulin-like growth factor-1
(IGF-1) in supplemented groups, whereas expression of inflammatory markers (TNF-α and IL-1β)
showed tissue-specific response. Cecal inflammatory gene expression was not significantly affected.
These findings indicate that DGP can be used in rabbit diets, alone or with functional additives, as a
promising strategy for supporting rabbit health and productivity. Further study is needed to evaluate
optimal inclusion levels, characterize bioactive components, assess long-term physiological effects,
gut microbiota outcomes, and assess economic viability under commercial production conditions.