کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8426371 1546050 2018 24 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Presynchronization by induction of a largest follicle using a progesterone device in GnRH-based-ovulation synchronization protocol in crossbred dairy cows
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Presynchronization by induction of a largest follicle using a progesterone device in GnRH-based-ovulation synchronization protocol in crossbred dairy cows
چکیده انگلیسی
The objective was to compare the fertility of dairy cows using a presynchronization protocol by induction of a largest follicle using a progesterone intravaginal device prior to an Ovsynch protocol (P4synch) with the Double-Ovsynch in lactating dairy cows. Lactating Bos indicus x Bos taurus crossbred cows (n = 440) were randomly allocated to one of two treatments: (I) Double-Ov (n = 228), GnRH (D-17), PGF2α 7 days later (D-10) and GnRH 3 days later (D-7) followed by an Ovsynch protocol 7 days later (GnRH on D0, PGF on D7, GnRH on D9); (II) P4synch (n = 212), insertion of a sustained release progesterone intravaginal device (D-10), 10 days later (D0) an Ovsynch protocol was initiated (GnRH on D0, PGF on D7, GnRH on D9) with progesterone device withdrawal on Day 7. All cows were artificially inseminated (TAI) 16 h after the second GnRH of the Ovsynch protocol and pregnancy diagnosis was performed by transrectal ultrasonography 30 and 60 days after TAI. A subset of cows (n = 52 for Double-Ov and n = 50 for P4synch) ultrasonography was performed on days 0, 7, 9 and 24 of the experimental period. There were no differences among treatments on presynchronization rate [presence of a follicle>12 mm on D0, Double-Ov 94.2% (49/52) and P4synch 92.0% (46/50); P = 0.66], follicular diameter on the 1st GnRH (Double-Ov 17.2 ± 0.7 mm e P4synch 18.6 ± 0.9 mm; P = 0.28), ovulation rate to the 1st GnRH [Double-Ov 86.3% (44/51) and P4synch 81.2% (39/48); P = 0.50], synchronization rate [presence of a follicle>12 mm on D9; Double-Ov 84.6% (44/52) and P4synch 86.0% (43/50); P = 0.84], follicular diameter on the 2nd GnRH (Double-Ov 17.5 ± 0.6 mm and P4synch 18.0 ± 0.5 mm; P = 0.48), ovulation rate to the 2nd GnRH [Double-Ov 90.9% (40/44) and P4synch 86.0% (37/43); P = 0.48] and CL diameter on D24 (Double-Ov 27.9 ± 0.7 mm and P4synch 29.4 ± 0.9 mm; P = 0.19). Corpus luteum presence on D0 was different (P = 0.03) among treatments [Double-Ov 57.7% (30/52) and P4synch 36.0% (18/50)]. There was no difference (P = 0.85) among the pregnancy per AI on day 30 [Double-Ov 39.0% (89/228) and P4synch 40.1% (85/212)], on day 60 [Double-Ov 34.8% (79/227) and P4synch 38.7% (82/212); P = 0.41] and pregnancy loss [Double-Ov 10.2% (9/88) and P4synch 3.5% (3/85); P = 0.08]. The presynchronization by induction of a largest follicle using a sustained release progesterone device prior to Ovsynch yielded similar results compared with the Double Ovsynch protocol on follicular development patterns and on the fertility of lactating dairy cows.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Theriogenology - Volume 119, 1 October 2018, Pages 233-237
نویسندگان
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