Loading Levi Lactobacillus brevis into chitosan-coated alginate microcapsules and their effect on the testicular tissue redox system in roosters of hen's broiler breeders

Microencapsulation protects lactic acid bacteria against adverse conditions of environment and gastrointestinal tract and increases their survival. This study was conducted with three treatments, namely control, alginate-L. brevis (AL-LAB), and alginate-chitosan-L. brevis (AL-CHI-LAB). The results showed that the zeta-potential for microcapsules fixed by AL-CHI–LAB and AL–LAB were -16.5 and -17.2 mV, respectively. The SEM images showed cubic and non-aggregated structures for three types of microcapsules. The significantly highest survival rate for the AL-CHI-LAB observed in the GIT simulated conditions (59/50 %), and the significantly highest survival rate for the AL-LAB at the in vivo conditions of the GIT (50 %). To investigate SOD and GPX gene expression levels in roosters' testicular tissues, L. brevis was fed (10⁶ CFU/g) to thirty-two roosters aged about 60 weeks for two months. The GPX gene expression level in the testicular tissue was higher in the AL-CHI-LAB (6.57) than other treatments and it was not significantly different from the AL-LAB (4.09). The SOD gene expression was not significantly different among treatments. The results indicated that AL-CHI-LAB could improve the antioxidant capacity of testicular tissues by increasing the GPX gene expression, thereby improving aging-related reproductive performance.