Influence of early progesterone removal on follicular development, expression of estrus, and pregnancy rates in presynchronized postpartum beef cows

IF 2.2 2区农林科学 Q1 AGRICULTURE, DAIRY & ANIMAL SCIENCE

Animal Reproduction Science Pub Date : 2024-06-20 DOI:10.1016/j.anireprosci.2024.107541

Samir Burato , Madison Blake Walker , Lucas Melo Goncalves , Nicola Oosthuizen , Saulo Menegatti Zoca , Darren Dwayne Henry , Francine Messias Ciriaco , Juliana Ranches , Pedro Levy Piza Fontes

{"title":"Influence of early progesterone removal on follicular development, expression of estrus, and pregnancy rates in presynchronized postpartum beef cows","authors":"Samir Burato , Madison Blake Walker , Lucas Melo Goncalves , Nicola Oosthuizen , Saulo Menegatti Zoca , Darren Dwayne Henry , Francine Messias Ciriaco , Juliana Ranches , Pedro Levy Piza Fontes","doi":"10.1016/j.anireprosci.2024.107541","DOIUrl":null,"url":null,"abstract":"<div>The objective of this study was to evaluate the impact of early progesterone removal on pregnancy rates to fixed-time artificial insemination (FTAI) in presynchronized beef cows. Postpartum beef cows (n = 882) were randomly assigned to 1 of 2 treatments: 1) 7&7 Synch: cows received a controlled internal drug release insert (CIDR) and a 25-mg injection of prostaglandin F2α on day 0, 100 μg of GnRH on day 7, a second injection of prostaglandin F2α (PG2) at CIDR removal on day 14, and a second injection of GnRH at FTAI 60–66 h after PG2 (day 17); 2) 7&6 Synch: cows received the same treatment as 7&7 Synch; however, CIDR removal occurred in conjunction with PG2 on day 13, while FTAI remained at 60–66 h after CIDR removal (day 16). Ovarian ultrasonography was performed to determine follicle diameter at PG2 and FTAI in a subset of cows (n = 40). Cows exposed to the 7&7 Synch tended to have larger follicle diameter at PG2 compared with 7&6 Synch cows (P = 0.09); however, there were no differences in follicle diameter at FTAI. No differences were determined between treatments for the expression of estrus (7&7 Synch: 61.6 ± 5.30; 7&6 Synch: 54.1 ± 5.45; P = 0.31) or pregnancy rates to FTAI (7&7 Synch: 60.8 ± 3.83; 7&6 Synch: 57.0 ± 3.84; P = 0.42). In conclusion, early removal of progesterone did not impact pregnancy rates in presynchronized beef cows.</div>","PeriodicalId":7880,"journal":{"name":"Animal Reproduction Science","volume":"267 ","pages":"Article 107541"},"PeriodicalIF":2.2000,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Animal Reproduction Science","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0378432024001325","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"AGRICULTURE, DAIRY & ANIMAL SCIENCE","Score":null,"Total":0}

引用次数: 0

Abstract

The objective of this study was to evaluate the impact of early progesterone removal on pregnancy rates to fixed-time artificial insemination (FTAI) in presynchronized beef cows. Postpartum beef cows (n = 882) were randomly assigned to 1 of 2 treatments: 1) 7&7 Synch: cows received a controlled internal drug release insert (CIDR) and a 25-mg injection of prostaglandin F_2α on day 0, 100 μg of GnRH on day 7, a second injection of prostaglandin F_2α (PG2) at CIDR removal on day 14, and a second injection of GnRH at FTAI 60–66 h after PG2 (day 17); 2) 7&6 Synch: cows received the same treatment as 7&7 Synch; however, CIDR removal occurred in conjunction with PG2 on day 13, while FTAI remained at 60–66 h after CIDR removal (day 16). Ovarian ultrasonography was performed to determine follicle diameter at PG2 and FTAI in a subset of cows (n = 40). Cows exposed to the 7&7 Synch tended to have larger follicle diameter at PG2 compared with 7&6 Synch cows (P = 0.09); however, there were no differences in follicle diameter at FTAI. No differences were determined between treatments for the expression of estrus (7&7 Synch: 61.6 ± 5.30; 7&6 Synch: 54.1 ± 5.45; P = 0.31) or pregnancy rates to FTAI (7&7 Synch: 60.8 ± 3.83; 7&6 Synch: 57.0 ± 3.84; P = 0.42). In conclusion, early removal of progesterone did not impact pregnancy rates in presynchronized beef cows.

查看原文本刊更多论文

早期去除黄体酮对产后同步化肉牛卵泡发育、发情表现和妊娠率的影响

本研究的目的是评估早期去除黄体酮对预同步化肉牛固定时间人工授精（FTAI）妊娠率的影响。产后肉牛（n = 882）被随机分配到两种处理中的一种：1）7&7 同步：奶牛在第 0 天接受可控内药释放插管（CIDR）和 25 毫克前列腺素 F2α 注射，第 7 天接受 100 μg GnRH，第 14 天移除 CIDR 时接受第二次前列腺素 F2α (PG2) 注射，PG2 注射后 60-66 小时（第 17 天）在 FTAI 接受第二次 GnRH 注射；2）7&6 同步：母牛接受的治疗与 7&7 Synch 相同；但在第 13 天切除 CIDR 的同时注射 PG2，而在切除 CIDR 后 60-66 小时（第 16 天）仍注射 FTAI。对一部分奶牛（n = 40）进行了卵巢超声波检查，以确定PG2和FTAI时的卵泡直径。与7&6 Synch奶牛相比，接触7&7 Synch的奶牛在PG2时的卵泡直径往往更大（P = 0.09）；但是，FTAI时的卵泡直径没有差异。在发情表现（7&7 Synch：61.6 ± 5.30；7&6 Synch：54.1 ± 5.45；P = 0.31）或FTAI妊娠率（7&7 Synch：60.8 ± 3.83；7&6 Synch：57.0 ± 3.84；P = 0.42）方面，各处理之间没有差异。总之，早期去除黄体酮不会影响同步化前肉牛的妊娠率。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Animal Reproduction Science 农林科学-奶制品与动物科学

CiteScore

4.50

自引率

9.10%

发文量

136

审稿时长

54 days

期刊介绍： Animal Reproduction Science publishes results from studies relating to reproduction and fertility in animals. This includes both fundamental research and applied studies, including management practices that increase our understanding of the biology and manipulation of reproduction. Manuscripts should go into depth in the mechanisms involved in the research reported, rather than a give a mere description of findings. The focus is on animals that are useful to humans including food- and fibre-producing; companion/recreational; captive; and endangered species including zoo animals, but excluding laboratory animals unless the results of the study provide new information that impacts the basic understanding of the biology or manipulation of reproduction. The journal''s scope includes the study of reproductive physiology and endocrinology, reproductive cycles, natural and artificial control of reproduction, preservation and use of gametes and embryos, pregnancy and parturition, infertility and sterility, diagnostic and therapeutic techniques. The Editorial Board of Animal Reproduction Science has decided not to publish papers in which there is an exclusive examination of the in vitro development of oocytes and embryos; however, there will be consideration of papers that include in vitro studies where the source of the oocytes and/or development of the embryos beyond the blastocyst stage is part of the experimental design.