Performance of lambs from pregnant ewes fed different nutritional levels and supplemented with chromium propionate

• Grant number: 25/04574-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: April 30, 2026
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Sarita Bonagurio Gallo
• Grantee: Helena Boss
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated research grant: 23/08188-0 - Supplementation with chromium propionate for pregnant ewes fed different nutritional levels and its effects on the sheep and offspring, AP.R

Abstract

Chromium is a mineral that has been studied as a nutritional supplement in animal production. Its ability to amplify intracellular insulin signaling increases the efficiency of energy distribution in the body, and it may have antioxidant action, especially in phases of high nutritional demand and situations of metabolic stress, such as the final phase of gestation. The objective of the project is to evaluate the supplementation of chromium propionate in diets with different levels of nutrients, at the end of the gestation of sheep, and to evaluate the effect on the dam and offspring. To evaluate the efficiency of chromium supplementation, both the ewe and the offspring will be measured in relation to performance, milk production, colostrum quality, blood parameters, gene expression and metabolomics. The experiment will take place in the Sheep Farming Sector of the School of Animal Science and Food Engineering of the University of São Paulo. A herd of 108 sheep will be used, which will be divided into randomized blocks, by type of delivery, in a 3 x 2 factorial, with three levels of nutrition and (2) with or without chromium. Chromium supplementation will be 0.5 mg of chromium propionate/kg/DM. CTL, fed with 100% of the nutritional recommendation, but without chromium supplementation; CTLCR, similar to CTL, but with chromium supplementation. LOW, fed with 80% of the nutritional recommendation and without chromium; LOWCR, similar to LOW plus chromium. PLUS, fed with 120% of the recommendation and without chromium, PLUSCR, with a diet identical to PLUS and chromium. The animals will be divided and treated from 100 days of gestation (DG) and ending supplementation at birth. The research project is extensive and is supported by FAPESP (2023/08188-0). This scientific initiation student is responsible for working with data on lambs from birth to slaughter. For this, male lambs will be confined from 60 to 120 days of age, where DMI will be measured daily and live weight, monthly. After slaughter, carcass, meat, viscera and adipose tissue parameters will be evaluated. For statistical analysis, PROC MIXED will be used and means will be compared using the Tukey test at 5% probability. The hypothesis is that chromium will mitigate the consequences of energy deficit in the case of low-nutrition diets and will increase the efficiency of the use of excess energy in the case of diets with more energy. (AU)