Title not available

Author(s)

Evandro Fernando Ferreira Dias

• Document type: Master's Dissertation
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT)
• Defense date: 2022-07-15

Examining board members

Miguel Henrique de Almeida Santana; Nara Regina Brandão Cônsolo; André Luiz Nagatani Rigueiro

• Advisor: Miguel Henrique de Almeida Santana

Abstract

The largest cattle production in Brazil is located in the Cerrado biome, with mostly Nellore animals, and due to climatic variations and low pasture performance at some times of the year, malnutrition of dams is evident. Consequently, offspring can be affected in their productivity throughout life. The insult or nutritional stimulus in prenatal pregnancy is called fetal programming. Thus, this dissertation aimed to identify possible alterations caused in the ruminal, cecal epithelium and ruminal content of beef cattle, subjugated to the effects of fetal programming (PF). For this, during pregnancy, 126 Nellore cows were divided into three nutritional plans, and (CP, PP and NP, respectively): 1/3 of the matrices received protein-energy supplementation throughout pregnancy, another 1/3 of the matrices only in the final third and 1/3 did not receive this nutritional stimulus, only mineral supplementation 0.03% of live weight. From birth to slaughter, all animals received the same treatments. In the fattening phase, feces were collected for subsequent analysis. During slaughter, parts of the ruminal and cecal epithelium were collected, together with the ruminal content of 15 animals, 5 of each treatment. Rumen and cecum lesions were evaluated after evisceration, where fragments of 1 cm² were collected from the cranial sac of the rumen and from the center of the cecal epithelium for histological evaluation. The amount of ruminal papillae was higher for pp treatment, when compared to the other Rumenite and cecum score did not present significant effect (P>0.05). The cecum of animals in CP treatments presented a lower number of calyx cells compared to the treatments of NP (P<0.01), as well as lower crypt depth (P<0.01). The present study highlighted an improvement in cecal morphometry of programmed animals in contrast to that of non-programmed animals. The microbiomes of the 15 animals were analyzed by metagenomics 16S of feces and rumen samples. The results showed a difference between the collection sites, in volume of microorganisms and diversity. However, there was no significant difference between the microbiome of the animals evaluated in this experiment. In summary, this dissertation brings great contributions to the field of fetal programming, with pioneering studies, contributing to the discovery of mechanisms associated with maternal nutrition and the impacts on its progenies. (AU)

• FAPESP's process: 20/15192-6 - Microbiome and epithelial characterization of beef cattle under fetal programming
• Grantee: Evandro Fernando Ferreira Dias
• Support Opportunities: Scholarships in Brazil - Master