A Review of Immunological Evaluation of Antiviral Activity of Methanolic Extract of <i>Piper</i> <i>guineense</i> against Newcastle Disease in Exoerimentally Infected Broiler Chickens

Abstract

Forty-eight day old broiler chickens kept in eight equal groups were given Piper guineense extract at dose levels of 50 and 100 mg /Kg of body weight administered in their drinking water for eight weeks. The birds were partitioned into five groups whereby the first group, the control group contained 8 birds that were vaccinated against Newcastle disease but were not given Piper guineense extract. The 2nd group contained birds that were vaccinated and given Piper guineense extract at the dosage level of 100 mg/Kg, while the 3rd group were also vaccinated and given 50 mg/Kg Piper guineense extract. Birds in the 4th group were not vaccinated but were given plant extract at the dosage level of 100 mg/Kg. The 5th group were given Piper guineense extract at the dosage level of 50 mg/Kg body weight but weren’t vaccinated. The birds were observed daily for general performance. Both the control group and the treatment groups remained healthy. The feed intake of experimental birds were not significantly different from the control. This shows that the Piper guineense extract does not affect the feed consumption of the experimental birds when compared to the control group. On the fifth week, the birds were challenged with velogenic strain of Newcastle disease virus. After two weeks of the challenge, the birds that survived were bled to determine the level of antibody response by the chickens against Newcastle disease using ?-haemagglutination inhibition test (an immunological reaction). Haematological parameters of the experimental chickens were also determined in order to know the health status of the birds. The antibody titre level of the experimental chickens treated with 100 mg/Kg of Piper guineense extract (log 26) had the highest mean value titre (log 26). Therefore, 100 mg/Kg of Piper guineense fruits is recommended to prevent Newcastle disease outbreak. The haematological parameters of experimental birds were not significantly different from the control groups. Therefore, the plant extract at both 50 mg/Kg and 100 mg/Kg body weight were not toxic to the experimental broiler chickens.