Progesterone profiles and oestrous cycle changes following superovulatory treatment of Holstein-Friesian dairy cows in a tropical environment.
Changes of progesterone (P4) profiles and oestrous cycle were investigated up to 70 days in 20 superovulated Holstein-Friesian cows in a dry tropical environment (Brazil). Superovulated cows showed no significant differences in relation to P4 level at the time of embryo recovery (39.0 +/- 27.1 nmol/L, P = 0.536), first and second (12.0 +/- 6.0 and 10.7 +/- 2.2 nmol/L, P = 0.543) cycle. There was a close correlation between serum P4 concentration and the number of corpora lutea (CL; 13.3 +/- 9.5) at the recovery (P < 0.0001). After the embryo collection, cows returned to cycle in different ways: (i) group of donors returning to cycle after 2.2 +/- 0.8 days, (ii) group with a delay of 11.0 +/- 1.9 days; and (iii) animals having a long (28.8 +/- 2.2 days) acyclic period, which is significant (P < 0.001). The remaining animals (30%) showed cystic ovarian malformations. P4 level at the time of embryo recovery does not influence the oestrous cycle changes. The results suggest that Holstein-Friesian donor cows may suffer from cystic ovarian degeneration and may have a long acyclic period after superovulatory treatment in a tropical climate.
Bényei
B
B
Research Institute, Faculty of Veterinary Science, Szent István University, Ullo, Dóra-major, Hungary. benyei@koki.hu
Kulcsár
Margit
M
Gáspárdy
A
A
Pécsi
Anna
A
D000222:Adaptation, Physiological; D000818:Animals; D001938:Brazil; D002417:Cattle / Q000097:blood / Q000502:physiology*; D004624:Embryo Transfer / Q000662:veterinary; D004971:Estrus / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000627:therapeutic use; D006358:Hot Temperature / Q000009:adverse effects; D011374:Progesterone / Q000097:blood*; D012098:Reproduction / Q000502:physiology; D013480:Superovulation / Q000187:drug effects / Q000502:physiology*; D014329:Tropical Climate
D011374:Progesterone; D005640:Follicle Stimulating Hormone