Journal of World's Poultry Research

56-59

Authors: Sita Prasad Tiwari

150 day old Vencobb broiler chicks were randomly allocated to 5 treatment groups with 3 replicates of 10 chicks in each to determine the effect of mannan oligosaccharide (MOS) and Saccharomyces cerevisiae in gut morphology of broilers. The trial lasted for 6 weeks. For microscopic examination the representative samples of each segment of intestine were collected and fixed in the 10% buffered formalin. No significant difference was observed in treatments at length of different segments of intestine and villus height/crypt depth ratio. Significant (P< 0.05) difference observed for the mean height of the duodenum, jejunum, and ileum villus amongst different dietary treatments, being highest in T 5 and lowest in T . Mean crypt depth of the duodenum and ileum villus also differed significantly (P< 0.05) amongst treatments. The highest mean crypt depth in the duodenum was recorded in T 5 and lowest in T 2 whereas the highest mean crypt depth of caecum was recorded in T 3 and the lowest in T 1 2 . Thickness of tunica muscularis was significantly (P< 0.05) decreased in all segments of intestine except colorectum as MOS and S. cerevisae added to the diet. Height of the epithelium of villi differed significantly (P< 0.05) amongst treatments in all segments of intestine except caecum being maximum in T and minimum in T . It was concluded that supplementation of MOS and S. cerevisiae improves the gut health of broiler chickens.

64-74

Authors: Mahmoud E. Sediek

The aim of this study was to evaluate the pathogenicity of seven variants of IBV isolates (Coded, 11, 15, 21, 13, 19, 22, 24) using commercial broiler chickens. These isolates isolated from 25 commercial broiler flocks raised in El-Behera and Kafr-Elsheikh governorates in 2013, and were identified by the AGPT against reference IBV Beaudette antiserum and RT-PCR and characterized by partial sequence analysis of S1 gene as variant 2 IBV strains. The results at 2 weeks of PI revealed that all isolates were able to induce serological response and respiratory signs in the form of conjunctivitis, mainly of a frothy type, associated with lacrimation, edema and cellulitis of the periorbital tissues, sneezing, coughing, tracheal rales and gasping were observed in all infected groups in a varying degrees and varying times of appearance and disappearance. In addition the birds appeared lethargic, reluctant to move. No mortalities were recorded during the course of experiment in all groups. The main lesions of PI were slight increase of mucin, congestion and presence of nasal exudate in the trachea and small patches of pneumonia in chickens challenged with 4 IBV isolates only (NO. 15, 21, 22, 24). Renal lesions (nephritis and enlarged kidney) which were induced in chickens challenged with 3 isolates (NO. 15, 21 and 24) were not as pronounced as seen in the field. Histopathological finding of PI, exhibited tracheal lesions with inflammatory cells infiltration in the lamina propria and submucosa, edema in the submucosa, desquamation of the lining epithelial of the mucosa and activation of goblet cells. In addition to renal lesions with interstitial nephritis which characterized by infiltration of inflammatory cells (heterophils, lymphocytes and plasma cells) in the interstitial tissue.