Effect of early weaning in Nellore cows on the gastrointestinal and seminal microbiome and morphology of ruminal and intestinal epithelium of the next progeny

• Grant number: 23/07354-4
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: September 28, 2023
• End date: August 31, 2024
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Arlindo Saran Netto
• Grantee: Germán Darío Ramírez Zamudio
• Supervisor: Carl Robertson Dahlen
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Institution abroad: North Dakota State University (NDSU), United States
• Associated to the scholarship: 22/03571-8 - Early weaning of Nelore cows and its effect on fetal programming and the productive and reproductive performance of the next progeny, BP.PD

Abstract

The embryonic and fetal phases are critical periods of development and establishment of tissues, organs, and metabolic and hormonal systems. During these phases, animals with some impairment in their development have a greater risk of complications in their future life, such as metabolic, endocrine, immunological, neurological, or reproductive deficiencies. The vast majority of studies in fetal programming are focused on the development of skeletal muscle tissue in the progeny. However, few studies have evaluated the consequences of fetal programming on the gastrointestinal tract of ruminants, despite this organ playing an essential role throughout the body. On the other hand, recent research has shown that the uterine environment is not sterile and that fetal organs and fluids can be colonized during pregnancy. In addition, evidence indicates that maternal nutritional status can modulate the microbial community of fetal mucous membranes and fluids, which can affect the health and productivity of the animal during postnatal life. Therefore, this proposal aims to evaluate the morphological differences of tissues of the gastrointestinal tract (rumen and small intestine), as well as the differences in the microbiota of fluids such as ruminal, intestinal, and seminal fluids of adult cattle that were exposed to different energy balances during the second trimester of pregnancy resulting from early (150 days) or conventional (240 days) weaning strategies imposed on their dams. Samples of fluids (ruminal, intestinal, and seminal) and tissues (rumen and intestine) will be collected from 57 Nellore feedlot bulls that were gestated in cows exposed to early or conventional weaning, and analyzed for fluid microbiome and tissue morphology. (AU)