Waihenya, Rebecca2016-05-282020-01-072016-05-282020-01-072002Waihenya, R. (2002). Investigations on the bioactivities of Abe secundiflora (Aloeaceae) on newcastle disease and fowl typhoid in local chickens (Gallus domesticus) in Tanzania. Doctoral dissertation, University of Dar es Salaam. Available at (http://41.86.178.3/internetserver3.1.2/detail.aspx?parentpriref=)http://localhost:8080/xmlui/handle/123456789/1897Available in print formThe bioactivities of the crude extract of Aloe secundiflora (Aloaceae) against Newcastle Disease (ND) and fowl typhoid were assessed in vivo, in embryonated chicken eggs (ECE) and in vitro. Five months old local chickens free of antibodies against ND and fowl typhoid were selected and the efficacy of Aloe treatment was studied. Results showed that there was delayed clinical signs and mortality in ND while there was reduced mortality rate and severity of clinical signs of fowl typhoid in Aloe treated chickens. In ND experiment, the Aloe extract did not affect either antibody or IL-6 levels, whereas in fowl typhoid, there was reduced antibody levels and a rise in IL-6 levels. The Aloe extract significantly reduced the multiplication of NDV in ECE, while it inhibited the growth of S. gallinarum in vitro as well as that of other bacteria causing diseases in chickens. Phytochemical fractionation of the crude extract using HPLC-MS revealed phenolic compounds mainly aloenin, aloenin B and Aloin (A and B). The fraction containing aloenin B showed the highest activity against S. gallinarum and inhibition of viral multiplication in ECE. The current study showed that there was some protection during ND, however, the mechanism was not clearly defined. In fowl typhoid, the reduced bacteria load was associated with antibacterial activity of the crude extract revealed by in vitro assays. The bioactivities of the crude extract account for the extensive use of the Aloe in rural poultry management.enNewcastle diseasesFowl typhoidAloeaceaeGallus domesticusTanzaniaThesis