Effect of dietary supplementation of probiotic on the performance of F1 crossbred (Rhode Island red male × Fayoumi female) cockerels.

A study was conducted to evaluate four different probiotic levels, using diets supplemented with 0 (control), 0.1%, 0.2%, 0.3% or 0.5% of organic-green culture-zs (probiotic). The cockerels of 6-weeks old were randomly divided into 15 separate floor pens each comprising 25 birds and three pens (replicates) per treatment group following completely randomized design. At 12 weeks of age BW and feed to gain ratio (FCR) were determined. At the end of 42 days of experiment, nine birds per treatment were sacrificed to evaluate carcass characteristics, abdominal fat contents and the internal organs. Blood haemato-biochemical parameters were also determined. Haemagglutination inhibition antibody titres against Newcastle disease virus and lymphoid organs weight/body weight ratio were also determined. The BW of birds fed 0.2-0.5% of probiotic was significantly greater than birds fed without probiotic diet. Similarly, better FCR was observed in birds those fed diets of high level of probiotic. There was no mortality recorded at higher levels of probiotics. Differences in carcass characteristics, organs weight, meat composition, haematological values and HDL and LDL concentrations among all the diets were non-significant. However, abdominal fat contents reduced significantly in supplemented groups in relation to control and cholesterol contents were reduced significantly in 0.3% or 0.5% supplemented groups in relation to control. Feeding levels of 0.2-0.5% of probiotic, did positively affect the immune system within the parameters measured. It may be concluded that performance, blood chemistry and immunity against disease in cockerels could be maintained when supplementing 0.3% or 0.5% level of probiotic incorporated in crossbred cockerel's diets.