hi

yes of course, I hope my research might help you

https://www.researchgate.net/publication/259990778_Influence_of_dietary_yeast_supplementation_on_growth_performance_of_Nile_Tilapia_%28Orechromas_niloticus%29_chronically_exposed_to_unionized_ammonia

Article Influence of dietary yeast supplementation on growth perform...

I don't agree completely.

Probiotics by definition are bacteria. As such, they hardly affect nitrogen excretion. However, there is the case, when intestinal stress affects protein (amino acid) absorption negatively. Supplementation of probiotics may help to stabilize the intestinal tract and enhance amino acid absorption.

But, if you have a well managed aquaculture facility, I would not expect probiotics to further reduce nitrogen excretion.

There are references that say probiotics can reduce the secretion of urea and ammonia in fish.

Lashkarbolouki, M., Jafaryan, H., Faramarzi, M., Zabihi, A. and Adineh, H. 2011. The effect of feeding with Saccharomyces cerevisiae extract (Amax) on ammonia and urea excretion in Persian sturgeon (Acipenser persicus) larvae by bioenrichment of Daphnia magna. Journal of research in Biology. 2: 110-115

Faramarzi, M., Jafaryan, H., Roozbehfar, R., Jafari, M. and Biria, M. 2012. Influences of probiotic bacilli on ammonia and urea excretion in two conditions of starvation and satiation in persian sturgeon (Acipenser persicus) larvae. Global Veterinaria. 8 (2): 185-189

The question was 'Can probiotics reduce nitrogenous excretion in fish'.

Whilst (prior to following the given references) I tend to stick to my answer, that probiotics will not reduce nitrogenous excretions in fish, I can see that there is potential for probiotics to affect the ratio of the various sources of nitrogen in the excreta.

Thank you for stating these references, which I will follow up soon.