Banca de DEFESA: FERNANDA BRUNEL DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : FERNANDA BRUNEL DA SILVA
DATE: 11/10/2023
TIME: 09:00
LOCAL: Web Conferência - Google Meet: https://meet.google.com/xvt-tzen-wdj.
TITLE:

Immune profile and performance of broilers from breeders of different ages and their relationship with reovirus arthritis.

KEY WORDS:

broiler; progeny; immunoglobulins; immunity; reovirus.

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUMMARY:

The broiler after hatching is not immunocompetent and depends on the transfer of maternal antibodies by the egg to develop protection against pathogens in the first days of life, for example, against avian reovirus. Currently, it is not clear how the age of the broiler breeder influences the transfer of immunoglobulins in the progeny. This way, in this study, the objective is to evaluate the effect of breeder age on immunity and performance of broilers and its relationship to the development of rheoviral arthritis. Was used 3.600 male broilers, ROSS 95, from heavy breeders of different ages, being the treatments, T1: 31 weeks; T2: 33 weeks; T3: 37 weeks; T4: 44 weeks. The birds was distributed in 72 boxes, with 50 birds in each box, totaling 900 birds for each treatment. Performance analyzes was carried out on the 1st, 7th, 14th, 21st, 28th, 35th and 42nd day of age of the broilers, to obtain the average weight (AW), weight gain (WG), feed conversion (FC) and mortality (MT). Blood samples was collected from broiler at the ages of 1, 21 and 42 days for the evaluation of the immunological profile through the immunocrit technique and ELISA titration for the serological diagnosis of reovirus. Data was analyzed using the SAS software (SAS Inst. Inc., Cary, NC, v.9.4). For the performance results, the AW of the broilers at 21 days, the WG from 15 to 21 days; WG from 22 to 28 days and WG from 29 to 35 days showed a quadratic effect (P<0.05). The broilers from T3 showed higher AW at 21 days of age (1052.890g) and WG from 15 to 21 days (479.833g) in relation to the other treatments (P<0.05). The WG from 22 to 28 days and WG from 29 to 35 days was higher for broilers from younger breeders (T1) at 31 weeks of age, these results being 853.667g and 719.833g, respectively when compared to the other treatments (P< 0.05). The FC and MT values of the broilers did not differ between the ages of the breeders of each treatment (P>0.05). The results of immunocrit and titers of antibodies to reovirus of broilers at the ages of 1, 21 and 42 days was similar regardless of breeder age (P>0.05). However, a significant difference was observed for these two parameters of broilers at different ages (1, 21 and 42), but from the same breeder laying age (P<0.05). The present study demonstrated that the age of the breeder influenced the average weight of broilers in the growth phase (21 days old), being greater in those from breeders with 37 weeks, however, the weight gain between the growth/final phase (22 to 35 days) was higher for broilers from younger breeders, at 31 weeks. According to the immunocrit and titration of antibodies against reovirus, there was no influence of breeder age on broilers immunity.

COMMITTEE MEMBERS:
Externo à Instituição - RICARDO CAVANI
Presidente - 2277465 - FABIANA MOREIRA
Interna - 1081425 - TEANE MILAGRES AUGUSTO GOMES