Kaixing Qu, Zhanxing He, Meifen Huang, Jicai Zhang, Ankui Wang, Xiandong Jin, Kai Yang, Fengwei Zhang, Bizhi Huang,
Reproductive Hormone Concentrations and Their Correlation of Different Physiological
Stages in Dulong Cows (Bos frontalis),
Journal of Animal and Veterinary Advances,
Volume 19,Issue 12,
2020,
Pages 159-166,
ISSN 1680-5593,
javaa.2020.159.166,
(https://makhillpublications.co/view-article.php?doi=javaa.2020.159.166)
Abstract: Plasma hormone levels were conducted
through radioimmunoassay from grazing Dulong cows.
Two surges of E2 profile were found on standing estrous
(18.56±7.87 pg mL–1) and on days 240-270 of pregnancy
(11.85±3.45 pg mL–1), the lowest on days 5-10 of
post-copulation (p<0.05). P4 concentration was found
the highest on days 5-10 of post-copulation
(9.35±2.84 ng mL–1) (p<0.01) and the lowest on standing
heat (0.29±0.13 pg mL–1), significantly lower than that
during gestation (p<0.05). A biphasic FSH surges were
observed during estrous forepart (2.03±0.54 mIU mL–1)
and on days 2-30 of postpartum (2.23±0.61 mIU mL–1).
Surge LH concentration reachedon days 5-10 of gestation
(10.21±9.04 mIU mL–1). Surge T level was found on days
240-270 of pregnancy, significantly higher than those in
other PPSs (p<0.01). The significant positive correlations
were found between PPSs and plasma FSH (r = 0.34,
p<0.05), P4 (r = 0.31, p<0.05), T (r = 0.48, p<0.01)
concentrations, respectively, also between P4 and LH
(r = 0.31, p<0.05), T and FSH (r = 0.40, p<0.01) while a
negative correlation was between plasma E2 and P4
(r = -0.29, p<0.05). In conclusion, Dulong cows were
found with two surges of hormone E2 and FSH and a
single surge of hormone P4 and T. There were increasing
at levels of FSH, P4 and T, the synergistic relationships
between P4 and LH, T and FSH, the antagonistic
relationship between E2 and P4, were firstly reported in
Dulong cows during PPSs.
Keywords: Dulong cow (Bos frontalis);hormone level;reproductive physiological stage;correlation;reproductive behavior