Global Veterinaria 8 (2): 185-189, 2012 ISSN 1992-6197 © IDOSI Publications, 2012 Corresponding Author: M. Faramarzi, Department of Fishery, Gonbad University of Agricultural Sciences and Natural Resources, Gonbad, Iran. 185 Influences of Probiotic Bacilli on Ammonia and Urea Excretion in Two Conditions of Starvation and Satiation in Persian Sturgeon (Acipenser persicus) Larvae Moein Faramarzi, Hojatollah Jafaryan, Reza Roozbehfar, Mahdieh Jafari and Mehdi Biria 1 1 2 3 3 Department of Fishery, Gonbad University of Agricultural 1 Sciences and Natural Resources, Gonbad, Iran Department Fisheries, Khorramshahr University Marine Science and Technology 2 Department Fisheries, Science and Research Branch, 3 Islamic Azad University, Khuzestan, Iran Abstract: This study (at 4 weeks) was carried out to evaluate influences of probiotic Bacilli on ammonia and urea excretion in Persian sturgeon ( Acipenser persicus) larvae. Bacillus bacteria ( B. licheniformis, B. subtilis and B. circulans) (three species in a commercial preparation, Protexin Aquatic) were bioencapsulated within Daphnia magna at three concentrations by holding the Daphnia in suspensions of 1×10 , 2×10 or 3×10 bacteria 7 7 7 per milliliter for 10 hours (T1, T2 and T3, respectively). The sturgeon larvae in experimental treatments were fed one of the three probiotic treatments at a level of 30 percent body weight 5 times a day but larvae in control treatment (C) fed by nubioencapsulated Daphnia. The ammonia and urea excretion in Persian sturgeon (Acipenser persicus) larvae fed by Daphnia enriched with protbiotic were compared to those larvae fed a control treatment of unbioencapsulated Daphnia magna. The results showed that ammonia and urea excretion in both two condition, in experimental treatments had significantly decreased in comparison to control treatment (P<0.05). Lower amount of ammonia and urea excretion in both two condition observed in treatment T2. Maximum amount of ammonia and urea in both two condition observed in control treatment. Also, there is significant different about ammonia and urea excretion in both two condition between experimental treatment (P>0.05). Results indicate that use of probiotics bacilli can reduce amount of ammonia and urea excretion. Key word: Acipenser Persicus %Probiotic Bacilli % Daphnia Magna %Ammonia and Urea Excretion INTRODUCTION art, from the empirical use to the scientific approach The abuse of antimicrobial drugs, pesticides and ponds include improvement of water quality with disinfectants in aquaculture has caused the evolution of decreasing of ammonia excretion, enhancement of resistant strains of bacteria and concern of the society nutrition of host species through the production of [1,2]. Thus, the use of probiotics in the culture of aquatic supplemental digestive enzymes, lower incidence of organisms is increasing with the demand for more diseases and greater survival and improved immune environment-friendly aquaculture practices [3]. Probiotics response [12]. is the use of microbial supplements to benefit their host The main end-product of protein metabolism in [4]. Although application of probiotics in aquaculture teleosts is ammonia and a significant proportion of seems to be relatively recent [5], the interest in such nitrogenous waste is also excreted as urea [13]. environment friendly treatments is increasing rapidly. Consequently, measurements of ammonia and urea Moriarty [6] proposed to extend the definition of excretion have been used as indicators of the effects of probiotics in aquaculture to microbial “water additives.” various environmental and nutritional factors on protein A growing number of studies have dealt explicitly with metabolism and can give an insight into the nitrogen probiotics and it is now possible to survey its state of the balance of fish [14-17]. Therefore, quantification of [7-11]. The potential benefits of probiotics in aquaculture