Submitted to: International Congress on Animal Reproduction
Publication Type: Abstract Only
Publication Acceptance Date: 2/3/2020
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The objective of this study was to evaluate the impact of nutritional changes prior to and after artificial insemination (AI) on uterine environment and plasma cholesterol concentrations. The study consisted of 79 beef heifers that were randomly assigned to 2 dietary treatment groups (High or Low) for 30d prior to AI (pre-AI). At time of AI, heifers were randomly divided and placed in new diet treatment groups (post-AI) which created four pre- x post-AI diet treatments (High- High, High-Low, Low-High, and Low-Low). Post-AI diet treatments continued 7 or 8d after AI when uteri were flushed for embryo recovery. The high diet provided 155% of maintenance and low diet provided 86% of maintenance. Blood samples were collected on d-3,-2,-1 and 0 (day of AI), 1,3,5,7, and 8 post-AI and blood was collected for analysis of plasma cholesterol concentrations using a colorimetric assay. Uterine flushes were analyzed for concentrations of Mg, Al, P, S, K, Ca, Cu, Zn, Se, and Fe by ICPMS. Plasma cholesterol and mineral concentrations were analyzed as repeated measures using the MIXED procedures in SAS. Cholesterol concentrations changed over time (P<0.0001), however there were no differences between treatments (P>0.10) and there was no pre-AI diet by post-AI diet by time interaction (P=0.99). There was an effect of embryo presence on uterine flush mineral concentrations for Mg (P<0.04), Al (P<0.01), S (P<0.01), K (P<0.01), and Ca (P<0.01), with concentrations decreased in uterine flushes that contained an embryo. There was no effect of pre-AI diet on mineral concentrations, however, there was an effect of post-AI diet on S (P<0.02) and Ca (P=0.03). Heifers on the high diet had increased concentrations of both S and Ca compared to heifers on the low diet. Mineral concentrations were not affected by the interaction of pre-AI diet by embryo presence with the exception of S (P<0.03). There was a post-AI by embryo interaction on P (P<0.03), Zn (P=0.02), and Se (P=0.02). In conclusion, changing the plane of nutrition pre- and post-AI had no effect on plasma cholesterol concentrations; however, the presence of an embryo as well as pre- and post-AI diet did affect uterine mineral concentrations.