کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2440722 1108125 2007 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synchronization of Estrus and Pregnancy Risk in Anestrous Dairy Cows After Treatment with a Progesterone-Releasing Intravaginal Device
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Synchronization of Estrus and Pregnancy Risk in Anestrous Dairy Cows After Treatment with a Progesterone-Releasing Intravaginal Device
چکیده انگلیسی

Lactating Holstein cows (located in 4 dairy herds) that had failed to display estrus as defined by increased pedometer activity by 63 ± 3 d in milk, were enrolled to investigate the effect of a progesterone-releasing intravaginal device (PRID, n = 268) relative to a placebo intravaginal device (PID, control, n = 266) on days from device removal to artificial insemination (AI), the probability of pregnancy at first AI, and days from device removal to pregnancy. Cows were assigned randomly to receive a PRID or PID for 7 d and an injection of PGF2α at device removal. Upon device removal, a vaginitis score was assigned and AI occurred at observed estrus. Cows failing to display estrus within 14 d of device removal were subjected to a subsequent reproductive exam and were treated with PGF2α. Two percent of PRID-treated cows and 11% of control cows displayed estrus during the 7-d exposure period. Among the remaining cows, 93% of the devices were present at the scheduled removal. Cows treated with the PRID were 60% less likely to have purulent debris on the device than control cows. Vaginal reaction, however, was not associated with any of the reproductive outcomes. Investigation of the reproductive outcomes revealed a treatment × parity interaction. Progesterone-treated primiparous cows were inseminated 17 d earlier, with no significant change in the probability of pregnancy at first AI (30.3 vs. 42.0%), and no difference in median time from device removal to pregnancy (52 vs. 53 d) relative to control primiparous cows. Conversely, PRID-treated multiparous cows were inseminated 8 d earlier, with no change in probability of pregnancy at first AI (24.6 vs. 18.8%); however, median time from device removal to pregnancy was reduced by 20 d (67 vs. 87 d). These results support the efficacy of a PRID to induce estrus in previously anestrous cows. The reason, however, for the variable response between primiparous and multiparous cows was not clear.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Dairy Science - Volume 90, Issue 3, March 2007, Pages 1139–1148
نویسندگان
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