Effect of energy sources (starch or fat) and Chromium Propionate supplementation, on high energy diet, on oocyte quality and on embryo produce on lactating dairy cows

• Grant number: 16/18877-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2017
• End date: February 28, 2018
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: José Luiz Moraes Vasconcelos
• Grantee: Ana Cláudia Fonseca
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The objective of this study is to evaluate the influence of the energy source of the diet and chromium propionate supplementation on oocyte quality and on embryo production on lactating dairy receiving in a 2 × 2 factorial design the following treatments: 1) concentrate based on ground corn (CRN; n = 20) or fat (GP; n = 20), and 2) supplemented (n = 20) or not (n = 20) with 2.5 g/d of Cr-propionate. During the experiment (d 0 to 200), 40 multiparous, non-pregnant, lactating Gir × Holstein cows (initial days in milk = 80 ± 7) were offered corn silage for ad libitum consumption, and individually received concentrate formulated to allow diets to provide 160% of their daily NEL requirements. Cow BW was recorded weekly and BCS was recorded each 15 days. Milk production was recorded daily. Oocytes were picked-up (n=3) at d-4, d98 and d198 to evaluate oocyte and embryo production. All embryos will be vitrified and then will be transferred in comercial receptors. All continuous variables will be analyzed using the MIXED and pregnancy data at 23 and 53 days after embryo transference will be analyzed using the GLIMMIX procedure of SAS. (AU)