Banca de QUALIFICAÇÃO: RENATO SOUTO MAIOR MUNIZ DE MORAIS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : RENATO SOUTO MAIOR MUNIZ DE MORAIS
DATE: 21/02/2024
TIME: 19:00
LOCAL: Videoconferência - Link: https://meet.google.com/jdp-fhws-oey
TITLE:

EVALUATION OF THE TRACHEA AND MAIN ZOOTECHNICAL DATA OF BIRDS NOT VACCINATED AGAINST THE CHICKEN INFECTIOUS BRONCHITIS VIRUS

KEY WORDS:

IBV; poultry farming; broiler chicken; histopathology; histomorphometry

PAGES: 25
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUMMARY:

Brazil is the second biggest chicken producer worldwide and the biggest exporter. In recent years, a growing number of studies have researched how to avoid the comdemnation of carcasses and also to identify the comdemnation causes. Little is known about the viral agents involved, such as the infectious bronchitis virus (IBV). This work aims to study morphological and histopatological alterations in birds not vaccinated against IBV at the age of slaughter and evaluate zootechnical performance. In total, 80 birds non vaccinated against IBV from Cobb or Ross lineages, aged 40 to 45 days were used. ELISA IDvet® and nested-PCR were performed as diagnostic test. For histomorphometry and histopathology, trachea fragments were collected, processed and stained with hematoxylin and eosin for optical microscope observation. Seven of the 15 batches tested positive by serology and none tested positive by Nested-PCR. The main histopathological findings were lymphoplasmacytic tracheitis, mucous gland hyperplasia and hypertrofia and deciliation. In histomorphometry, IBV-positive animals had an average tracheal mucosa thickness of approximately 11% higher than IBV-negative animals. The evaluated zootechnical parameters were mortality percentage, average weight of birds, daily weight gain and food conversion and production fator. Of these parameters, only mortality percentage had a significant difference between IBV-positive and IBV-negative animals. The production factor values, despite not being statistically different between IBV-positive/negative, shows a better performance for IBV-negative lots. The presence of IBV can cause damage to tracheal mucosa. This causes thickening of the tracheal mucosa in birds with active inflammatory processes. IBV in the broiler flock relates to a higher mortality and therefore with lower production effiency.

COMMITTEE MEMBERS:
Presidente - JOAQUIM EVENCIO NETO
Externa à Instituição - PRISCILLA MARIA CAVALCANTE ROCHA
Externa à Instituição - WANESSA NOADYA KETRUY DE OLIVEIRA