Effects of Planes of Nutrition on Bodyweight, Haematology and Immune Response in Broiler Chickens Vaccinated with Newcastle Disease i-2 or Lasota Vaccines

Abstract

The objective of this study was to investigate the effects of planes of nutrition on body weight, haematology and immune responses in broiler chickens vaccinated with NDV I-2 and Lasota vaccines. Two hundred (200) day old broiler chicks of Anak 2000 strain were used for the study. They were randomly assigned into nine groups of 20 birds each. Three feed types (A, B, C) were compounded for the study. Proximate analyses of the feeds were carried out. The groupings are A1 (feed A + I-2 vaccine), A2 (feed A + lasota vaccine), A3 (feed A + no vaccine), B1 (feed B + I-2 vaccine), B2 (feed B + lasota vaccine), B3 (feed B + no vaccine), C1 (feed C + I-2 vaccine), C2 (feed C + lasota vaccine), C3 (feed C + no vaccine). Feeding and provision of water were ad-libitum for the 9 week period of the study. Weight gain was determined on weekly basis . Packed cell volume (PCV), hemoglobin concentration (HbC), total leucocyte counts (TLC) and differential leucocytes counts (DLC) were carried out on weeks 1, 3, 6 and 9 of the experiment following standard procedures. Serum samples were collected from 4 birds each from the nine groups at weeks 1, 3, 6 and 9 for haemaglutination and haemaglutination inhibition tests. Ten birds each were randomly selected from the different groups and challenged with virulent Newcastle disease virus strain Kuru duck-113 (Kudu113). The birds were monitored for clinical signs and those that died were necropsied. Data obtained were analysed using one way analysis of variance (ANOVA) and variant means were separated by duncan multiple range test. Antibodies in broilers in different dietary groups were compared. All tests were performed at a 5% level of probability. Proximate analyses of the feeds showed that feeds A, B, C had 98.61%, 97.67% and 97.76% dry matter, 24.21% , 22.19% and 20.05% crude protein, 9.25% , 8.11% and 7.25% ash, 6.9% , 6.6% and 5.2% crude fiber, 3.95% , 5.46% and 6.2% oil, 58.77% , 56.73% and 55.73% energy and 6.4% , 5.9% and 5.4% moisture for the starter feed respectively while the finisher feeds A, B, C had 97.78% , 97.54% and 97.47 % dry matter, 22.00% , 20.04% and 19.61% crude protein, 10.25% , 9.32% and 8.30% ash, 5.4% , 5.0% and 4.2% crude fiber, 3.6% , 5.45% and 6.31% oil, 58.13% ,57.89% and 56.03% energy and 5.3% , 4.2% and 3.9% moisture respectively. The mean weight gain of groups fed feed A were significantly higher (p<0.05) than those fed feeds B and C from week 1 to 9. The mean packed cell volume and haemoglobin concentration significantly (p<0.05) increased from week 1-9 for all the groups. The mean total leucocyte count significantly increased (p<0.05) from week 1- 6 and then significantly decreased (p>0.05) at week 9 in all the groups. The mean absolute heterophil, lymphocyte and eosinophil counts significantly increased (p<0.05) from week 1- 6 and then significantly decreased (p>0.05) at week 9 in all the groups. There was no significant difference (p>0.05) in the mean monocyte and basophil counts in all the groups from week 1- 3 but significantly increased (p<0.05) at week 9. The mean HI titres significantly (p<0.05) increased from week 1 to 3 and then decreased from week 6 to 9 in all the groups. The mean HI titres obtained from groups fed feed A were significantly (p<0.05) higher than the other two groups fed feeds B and C from week 1 - 9. The mean HI titres obtained from the vaccinated groups were significantly (p<0.05) higher than the unvaccinated control from week 1 - 9. The prominent clinical signs observed were anorexia, greenish diarrhea, torticollis, ruffled feathers, laboured breathing, twitching of the neck muscles, paralysis of the legs, etc. The gross lesions also observed were haemorrhages in the duodenum, jejunum, cecal tonsils and thigh muscles, cloudy air sac, pin-point haemorrhages in the proventriculus, congested lungs, kidneys and liver, enlarged liver and spleen. The mortality rate and percentage protection levels for the groups given laSota did not significantly (p>0.05) differ from the groups given I-2 vaccine, but they differed significantly (p<0.05) from the unvaccinated control groups. The mortality rate and percentage protection levels for the groups feed on feed A significantly differed (p<0.05) from the groups fed on feed B and feed B groups differed significantly (p<0.05) from the feed C groups. body weight