Tilapia culture has been Ghana’s topmost aquaculture practice for years now. It is responsible for over 70% of its total annual aquaculture production in the country. Intensification efforts by fish farmers to increase tilapia production has been challenging due to several factors such as the occurrence of diseases, mostly from viral, bacterial and fungal sources. These diseases are detrimental to both the fish and the farmer as huge sums of money are lost due to mortalities. Farmers try to prevent and salvage their fish stock by resorting to the use of antibiotics. However, probiotics have been found to boost the growth and health of fish when consumed. This is achieved by improving their defensive mechanisms to fight any disease intrusion. Probiotics are also known to have no negative side effects on both fish and the consumer’s health.
The main aim of this study was to determine the feeding effects of three commercial dietary probiotic products on growth performance and haematological parameters of juvenile Nile tilapia. The treatment diets were prepared using a floating tilapia feed containing 40% crude protein. The probiotics were added to the basal diet as follows: PB1: 12.5 ml/kg; PB2: 0.1g/kg and PB3: 5g/kg while the control group had only the basal diet sprinkled with 10 ml/kg of distilled water. A mean weight of 10g fish of 15 individuals were placed in 40L glass aquaria tanks with 3 replicates in a flow through system. They were fed the diets for 12 weeks before blood samples were taken in EDTA tubes for the haematological analysis. Water quality parameters were recorded over the period and fish weights determined fortnightly. Results showed no significant difference in growth parameters of the control and probiotic diets (P=0.047) although the control group had the highest final weight. However, there were significant differences in the haematological parameters with P-values of 0.0430, 0.0014 and 0.0064 for Hb, RBC and WBC counts respectively.