Amino acids profile within peripheral blood and follicular fluid based on high‐performance liquid chromatography methods may explain differences in folliculogenesis between short‐term under/over‐fed treatments during luteal phase of Hu sheep

Abstract

The nutritional alteration of amino acids (AAs) profile in physiological fluid was poorly characterized in livestock. After oestrus synchronization, 24 ewes were randomly assigned to two groups based on the nutrient requirement recommended for maintenance (M): the feed-supplemented group (S, 1.5 × M, N = 12) and feed-restricted group (R, 0.5 × M, N = 12) on days 6-12 of their oestrous cycle, which occurred shortly before ovulation. The concentration of 30 AAs in peripheral blood (PB) and follicular fluid (FF) was quantified to calculate the PB-to-FF concentration gap for each AA and determine its correlation with metabolites and hormones in PB and FF. Results showed that the feed restriction enlarged the oestrous cycle length, decreased the number of follicles 2.5-3.5 mm, increased the number of follicles >3.5 mm and augmented the volume of follicles >2.5 mm. Nineteen AAs from PB were significantly different between the groups. The phosphoethanolamine (PEtN) and ration of essential AAs to nonessential AAs (EAA/NEAA) in FF significantly (p < 0.05) increased and decreased in the R group, respectively. Most AAs, except aspartate (Asp) and carnosine (Car) in the R group and alanine (aAla) in both groups, were significantly lower within FF than those within PB. The correlation of AAs with FSH and progesterone (P ) was more significant than that of AAs with other endocrine milieu characteristics. In conclusion, our results revealed that the influence of short-term nutritional manipulation during luteal phase on folliculogenesis might not be due to the variation of intrafollicular AAs profile but rather attribute to the peripheral blood AAs profile alteration.

Factors affecting oocyte quality in New Zealand dairy cows

“…Forde et al (2016) reported FF ornithine had a significant positive correlation with serum IGF1 and insulin, and a significant negative correlation with serum BHBA in heifers and lactating cows. This is consistent with Nie et al (2019), who reported that FF ornithine had a significant positive correlation with follicular insulin and glucose and a negative correlation with follicular NEFA concentrations in ewes fed restricted or supplemented diets. These effects were specific to ornithine and not the other amino acids measured in this study, with the exception of arginine which also had a positive correlation with FF glucose concentration (Nie et al 2018).…”