Abstract:
Poultry farmers often supplement the feed of their birds with certain levels of antibiotics not only for therapeutic reasons but to improve growth performance. This approach often gets rid of the beneficial flora and exposes the birds to infection. Spice like Allium cepa are known to contain compounds with antibacterial, antifungal and antitumor properties while probiotics like Saccharomyces boulardii confer health benefits on the host when taken in sufficient amount. This study was carried out to see how the enhancement of the microflora of the birds can impact on growth performance, haematology and serum biochemistry of the cockerels. The experiment was carried out with a total of one hundred and twenty (120) one-day old cockerels. This experiment lasted for ten weeks and employed a completely randomized design. The birds were grouped into 6 treatments groups (A, B, C, D, E, F) after brooding together for two weeks. Group A had their feed supplemented with Allium cepa 5 g/kg of feed, B with Saccharomyces boulardii 0.5 g/kg of feed, C a combination of 5 g A. cepa and 0.5 g S. boulardii per kg of feed while F served as the control. Treatment was carried out for four weeks and stopped with vaccination of the groups to be challenged on the 6th week with La Sota strain of Newcastle Disease Virus. An interval of 2 weeks was allowed for the antibody production of the vaccinated birds to peak. Data were collected on feed intake and weight gain, while blood samples were collected for haematological and serum biochemical indices determination. The birds in Groups A to E were challenged with kudu 113 strain of the velogenic Newcastle Disease Virus. Birds in Group B had a better feed conversion (1.86:1) compared with the control group (1.91:1) while Group A reduced the feed conversion (2.06). Statistically, there was no significant difference in the total cholesterol throughout the duration of the experiment (p < 0.05). However, there was a statistical difference in the total white blood cell after challenge between group B (54.25±0.247) and the control (36.50±0.141). The treated groups showed a slower ESR (A: 2.02±0.240, B: 3.91±1.202, F: 6.59±0.042) and PCV (A: 25.75±0.354, B: 22.75±0.354, F: 18.50±2.121). The treated groups also showed a consistently lower AST (A: 55.93±0.798, B: 53.42±0.265, and F: 67.59±0.236) and ALT (A: 0.85±0.050, B: 0.06±0.106, and F: 1.95±0.134) compared to the control groups. There was also a 50% mortality in the virus validation group (E) while there was none in the treatment groups and vaccine control group (D). Groups A and B showed less than 7 days morbidity after challenge compared to the control groups where the survivals remained morbid throughout the two weeks post-challenge monitoring period. Group B showed a higher Haemagglutination Inhibition titer (1/16) two weeks post-challenge compared to the other groups. Our findings suggests that A. cepa and S. boulardii had the potential to replace antibiotics use in commercial poultry farms. There is still the need for further studies to find the best combination and optimum supplementation amounts for the best poultry yield.
