Factors affecting the success of resynchronization protocols with or without progesterone supplementation in dairy cows

نویسندگان

  • Annette Forro
  • Georgios Tsousis
  • Nicola Beindorff
  • Ahmad Reza Sharifi
  • Christos Brozos
  • Heinrich Bollwein
چکیده

The objective of this study was to investigate factors that influence the success of resynchronization protocols for bovines with and without progesterone supplementation. Cow synchronized and not found pregnant were randomly assigned to two resynchronization protocols: ovsynch without progesterone (P4) supplementation (n = 66) or with exogenous P4 administered from Days 0 to 7 (n = 67). Progesterone levels were measured on Days 0 and 7 of these protocols as well as 4 and 5 days post-insemination. Progesterone supplementation raised the P4 levels on Day 7 (p < 0.05), but had no overall effect on resynchronization rates (RRs) or pregnancy per artificial insemination (P/AI). However, cows with Body Condition Score (BCS) > 3.5 had increased P/AI values while cows with BCS < 2.75 had decreased P/AI rates after P4 supplementation. Primiparous cows had higher P4 values on Day 7 than pluriparous animals (p = 0.04) and tended to have higher RRs (p = 0.06). Results of this study indicate that progesterone supplementation in resynchronization protocols has minimal effects on outcomes. Parity had an effect on the levels of circulating progesterone at initiation of the protocol, which in turn influenced the RR.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Effects of two different protocols: injection of progesterone vs. injection of GnRH+PGF2a on the onset of estrus in dairy cows with postpartum anestrous

Postpartum anestrous is one of the most important problems in the dairy industry in the world and especially in Iran. The objective of present study was to compare the efficacy of two hormonal programs for recycling of postpartum anestrous cows. For this reason, 230 Holstein cows from 4 similar dairy herds (with totally 2560 cow and unique management and feeding system) located on the suburb of...

متن کامل

Effects of two different protocols: injection of progesterone vs. injection of GnRH+PGF2a on the onset of estrus in dairy cows with postpartum anestrous

Postpartum anestrous is one of the most important problems in the dairy industry in the world and especially in Iran. The objective of present study was to compare the efficacy of two hormonal programs for recycling of postpartum anestrous cows. For this reason, 230 Holstein cows from 4 similar dairy herds (with totally 2560 cow and unique management and feeding system) located on the suburb of...

متن کامل

The Effect of Administering Equine Chorionic Gonadotropins (eCG) on Reproductive Performance of Dairy Cows with a CO-Synch + CIDR Protocol and Insemination at a Fixed Time

The success of a fixed-time artificial insemination (FTAI) program depends on a high ovulation rate during a short interval. Equine chorionic gonadotropin (eCG) has been used in FTAI protocols to improve follicular growth and thereby to produce larger, more responsive follicles for ovulation with increased pregnancy rates. The aim of the present study was to evaluate the effects of eCG on concept...

متن کامل

Effects of Fat Supplementation and Chop Length on Milk Composition and Ruminal Fermentation of Cows Fed Diets Containing Alfalfa Silage

The aim of this study was to evaluate the effect of fat supplementation for enhancing milk conjugated linoleic acid (CLA) in early lactation without affecting ruminal fermentation. 24 Holstein dairy cows were assigned to a completely randomized design employing a 2 × 4 factorial arrangement. Factors were particle size (15 and 25 mm) and two different sources of alfalfa supplemented with and wit...

متن کامل

O-11: Immunoneutralization of Inhibin Alpha Subunit as A Tool for Improving Farm Animal Fertility

Background: The objectives of a series of studies undertaken was to improve farm animal reproductive efficiency in terms of embryo production efficiency, conception rate and litter size by immunoneutralization of inhibin in conjunction with other conventional reproductive techniques. Materials and Methods: A recombinant porcine inhibin alpha-subunit mature peptide was produced by mass scale and...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 16  شماره 

صفحات  -

تاریخ انتشار 2015