# Synergistic Effect of Citric By-Product, Fibrolytic Enzyme and Lactobacillus spp. to Enhance Broiler Performance

## TL;DR

Adding fibrolytic enzymes and Lactobacillus to citric acid by-product diets improves broiler growth and meat quality without harming health.

## Contribution

Combining citric acid by-product with fibrolytic enzymes and Lactobacillus spp. enhances broiler performance and meat traits.

## Key findings

- Broilers on CABP diets with additives had higher body weight and weight gain.
- Carcass traits were unaffected, but meat hardness decreased with CABP+FL.
- Liver enzymes remained stable, indicating no adverse effects from additives.

## Abstract

This study evaluated the effects of using citric acid by-product (CABP) in combination with feed additives, namely fibrolytic enzymes and Lactobacillus spp., in broiler diets. CABP is considered a potential alternative energy source and a nutrient-rich ingredient for poultry. The evaluation covered growth performance, carcass quality, hematology, and economic return. Broilers fed CABP-based diets with enzyme and/or probiotic supplementation showed improved growth performance compared with CABP alone, without adverse effects on liver enzyme activities or carcass traits. Because all diets contained CABP and a conventional corn–soy control was not included, the findings should be interpreted as relative to CABP-only diets. Further studies are needed to confirm whether enzyme and probiotic supplementation can mitigate the limitations of CABP compared with standard commercial formulations.

This study evaluated the effects of citric acid by-product (CABP), either alone or in combination with fibrolytic enzyme (F) and Lactobacillus spp. (L), in broiler diets. A total of 160 one-day-old male Arbor Acres broiler chicks (average initial body weight 43.0 ± 0.16 g) were randomly assigned to four CABP-based diets (4 replicates × 10 birds each): 12% CABP, CABP+F (0.05%), CABP+L (0.025%), and CABP+FL (0.05% F + 0.025% L). Birds were fed for 35 days in three phases: starter (days 1–10), grower (days 11–24), and finisher (days 25–35). Compared with the CABP-only group, broilers receiving CABP+F, CABP+L, or CABP+FL exhibited higher body weight and weight gain during the finisher and overall phases (p < 0.05). Carcass traits did not differ significantly among treatments, although meat hardness was reduced in the CABP+FL group (p < 0.05). Additive-supplemented groups also showed changes in intestinal morphology, with a lower villus height-to-crypt depth ratio compared with CABP alone. Red blood cell counts were not different between CABP and CABP+L, while hepatic enzyme activities (ALT, AST, ALP) remained unchanged across treatments, indicating no adverse effects on liver function. Overall, supplementation of CABP-based diets with fibrolytic enzymes and/or Lactobacillus spp. improved broiler performance and certain meat quality traits relative to CABP alone, without negative impacts on liver health or carcass yield. However, as no conventional corn–soy control diet was included, the results should be interpreted as comparisons within CABP-based diets.