Effect of a new device for sustained progesterone release on the progesterone concentration, ovarian follicular diameter, time of ovulation and pregnancy rate of ewes.
This study evaluated the effectiveness of a new progesterone intravaginal device (DPR) in ewes through four experiments: Experiment 1 compared the circulating progesterone concentration of ovariectomized ewes that received either a new or a re-used DPR. Experiment 2 compared the progesterone concentration between DPR-estrous-synchronized ewes and naturally estrous-cycling ewes. Experiment 3 evaluated the effect of new and re-used DPRs on ovarian follicular dynamics and time of ovulation of estrous cycling ewes. Experiment 4 compared the pregnancy rate after the use of a DPR and Controlled Internal Drug Releasing Device (CIDR). The mean concentration of progesterone released by the DPR device during its first use (New Group: 5.1 ± 0.5 ng/ml) was greater than that during the second use (Re-used Group: 2.4 ± 0.3 ng/ml). There was no difference between the animals that received DPR devices for first and second use in terms of ovulatory follicle diameter, follicular wave emergence day for ovulatory follicle and period of ovulatory wave of ovarian follicular development. However, there was a significant difference between groups regarding the time between DPR device removal and first ovulation (New Group: 71.7 ± 2.5h and Re-Used Group: 63.9 ± 2.7h). Pregnancy rates were similar between ewes with DPR and CIDR devices. It was concluded that DPR is effective in increasing and maintaining progesterone concentrations, controlling follicular dynamics, promoting synchronized times of ovulation from healthy follicles, promoting development of a competent corpus luteum and when used results in pregnancy rates similar to that with use of the CIDR.
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil. Electronic address: lilikirsch@gmail.com.
Lilian Mara Kirsch
LM
Dias
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil.
Marina Berrettini Paes
MB
de Barros
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil.
Priscila
P
Viau
Department of Veterinary Medicine, University of Lavras, Lavras, MG, Brazil.
José Nélio de Sousa
JN
Sales
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil.
Renato
R
Valentim
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil.
Fernanda Ferreira
FF
dos Santos
Animal Reproduction Department, Dorper Campo Verde, CEP 13240-970, Jarinu-SP, Brazil.
Manoel Claudio
MC
da Cunha
Brazilian Agricultural Research Corporation (Embrapa) - Beef Cattle, Campo Grande-MS, Brazil.
Carolina Tobias
CT
Marino
Animal Reproduction Department, FMVZ/USP, CEP 05508-000, São Paulo-SP, Brazil.
Claudio Alvarenga
CA
de Oliveira
D000282:Administration, Intravaginal; D000818:Animals; D004973:Estrus Synchronization / Q000379:methods; D005260:Female; D007315:Insemination, Artificial / Q000662:veterinary; D006080:Ovarian Follicle / Q000033:anatomy & histology / Q000187:drug effects*; D010060:Ovulation / Q000187:drug effects*; D011247:Pregnancy; D011374:Progesterone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D012756:Sheep / Q000502:physiology*
D011374:Progesterone
FTAI; Fertility; Follicle; Progesterone; Reproduction; Santa Inês