Effect of prolonged supplementation of unsaturated fatty acids in the diet of Bos taurus heifers on oocyte and embryo quality and metabolic profile

Author(s)

Lenita Camargo Verdurico

• Document type: Doctoral Thesis
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2015-03-06

Examining board members

Francisco Palma Rennó; Pietro Sampaio Baruselli; Jefferson Rodrigues Gandra; Mauro Dal Secco de Oliveira; Arlindo Saran Netto

• Advisor: Francisco Palma Rennó

Abstract

This study aimed to evaluate the effects of different sources of essential fatty acids, omega 3 and omega 6, and the time of supplementation on oocyte and embryo quality in Holstein heifers. Will be selected 30 heifers Bos taurus, evenly divided into three groups which will receive the following diets: 1) Control (CT) basal diet composed of approximately 2,5% ethereal stratum; 2) Soya Bean (GS) consists of a diet with approximately 4,5% of ethereal layer based on inclusion of 12% of raw soybean and complete the concentrate, a source of omega 6; 3) Flax Seed (SL) composed of a diet with approximately 4,5% ethereal stratum based on inclusion of 6,0% of flaxseed in the concentrate, a source of omega 3. The animals are hand fed into groups according to the dry matter intake inside the day in order to be kept remains percentage of the diets on a daily basis between 5 and 10%. Will be evaluated by ultrasound ovarian activity of all animals throughout the collection period. Be preceded by follicular aspiration performed synchronization emergency follicular wave into six periods, - 30, 0, 30, 60, 90 and 120 days, the oocytes retrieved will be ranked according to their morphology, by measuring the amount of layers and compacting cumulus cells and homogeneity of the ooplasm. Are considered viable and therefore only the recovered oocytes for IVF classified as grade I, II and III, the other is discarded. Follicular fluid samples of the dominant follicle and the concomitant blood will be collected follicular aspiration in order to evaluate the metabolic and hormonal parameters such as glucose, total cholesterol, HDL cholesterol, VLDL cholesterol, LDL cholesterol, triglycerides, and urea. As expected outcome of the present study suggest that supplementation with fat has beneficial effects on follicle, the oocyte quality, the quality of in vitro embryo production and metabolic and hormonal profile of dairy heifers. There was a time effect on the number of oocytes classified as Class I, number and rate of embryos. In assessing orthogonal contrasts, effect was observed for the first contrast (CT vs GS + SL) when analyzing the rate of viable embryos, where the CT diet showed lower performance. There was no significant treatment effect on daily weight gain and body weight of heifers, where the average daily gain weight (GPD) between treatments was 1072 grams for the control group, 972 grams for the group treated with grain of soybeans and 840 grams for supplementation with flaxseed. There was a time effect for weighing animals fed experimental diets, it was observed a significant increase in initial weight to the final weight of the treated animals. In assessing orthogonal contrasts, effect was observed for the first contrast (CT vs GS + SL) for the GPD (daily weight gain) in the animals treated with the control diet showed higher values for average found weight gain, compared to diets with added lipid. However, when we analyzed the contrast 2 (GS vs SL) was not observed statistical effect of the tested variables. There was a time effects for all variables examined the metabolic profile of blood throughout the experimental period. There was a significant interaction effect between time and diet to the variable glucose. In the analysis of contrasts effect was observed for C1 (control versus soybean grain, flaxseed) where the animals fed the control diet had an average of 152.29 mg / dL glucose compared to those fed diets supplemented with acid sources fatty (GS and SL) (141.74 + 144.78) respectively. There was no effect for interaction between time and diet for urea. In the analysis of follicular fluid was observed interaction between time and diet for the variables Total cholesterol and urea. Diet Significant effects were observed, time and diet interaction Contrast 1 (CT vs. GS + SL) where it is examined the amount of triglycerides in the follicular fluid. Therefore prolonged supplementation sources of unsaturated fatty acids in the diet of heifers not considerably improvements in oocyte and embryo quality animal, only increasing the rate of viable embryos, but with losses on the metabolic profile and average live weight gain. (AU)

• FAPESP's process: 12/02072-6 - Effect of prolonged supplementation of unsatured fatty acids in the diet of Bos taurus heifers on oocyte and embryo quality, hormonal and metabolic profile
• Grantee: Lenita Camargo Verdurico
• Support Opportunities: Scholarships in Brazil - Doctorate