Document Detail

Effects of treatment of anestrous dairy cows with gonadotropin-releasing hormone, prostaglandin, and progesterone.
MedLine Citation:
PMID:  20412908     Owner:  NLM     Status:  MEDLINE    
Cows anestrous at the start of a seasonal breeding period have lesser probability of breeding, lesser conception rates, and a longer interval to conception than cycling herdmates. Historically, treatment included estradiol benzoate, which is no longer available. Consequently, alternative programs are required. Hence, a study was undertaken to assess new treatment regimens for these cows. The presence or absence of a corpus luteum was determined using ultrasonography in cows (n=2,222 from 12 herds) that were not detected in estrus by 9 d before the start of breeding. Cows were then randomly assigned to one of 4 treatments within each herd. Treatments were (1) 100 microg of gonadorelin, followed 7 d later by 500 microg of sodium cloprostenol, followed 54 to 56h later by 100 microg of gonadorelin, followed by fixed-time artificial insemination at 13 to 18h after the final GnRH injection (Ovsynch); (2) as for (1) but with placement of an intravaginal progesterone (P4)-releasing insert between the initial GnRH and PGF(2alpha) (Ovsynch-56+P4); (3) as for (2) but with the final GnRH treatment delayed until 71h after PGF(2alpha) and P4 insert removal with fixed-time artificial insemination 0 to 5h after GnRH treatment and with insemination of those cows detected in estrus before the second GnRH injection (Cosynch-72+P4); and (4) untreated controls (control). Day 0 was defined as the day of the second GnRH injection. Milk samples were collected from 154 and 152 cows from the Ovsynch and Ovsynch-56+P4 treatments, respectively, at d 0, 7, and 14 for P4 concentration determination. This was to test the hypothesis that inclusion of P4 would result in a greater proportion of cows having normal luteal function after treatment in these 2 groups that differed only in the inclusion of P4 in the Ovsynch-56+P4 treatment. All treatments resulted in shorter intervals from first day of breeding to conception compared with the controls. The Ovsynch-56+P4 treatment resulted in start of breeding to conception intervals 3, 6, and 16 d shorter than those of Cosynch-72+P4, Ovsynch, or controls, respectively, and the positive effect of the Ovsynch-56+P4 treatment occurred both in corpus-luteum-positive and in corpus-luteum-negative cows. The Ovsynch-56+P4 treatment resulted in fewer short interestrus intervals than did Ovsynch (i.e., <18 d; 16 vs. 31%) and more cows with elevated (>1 ng/mL) milk P4 concentrations at d 7 (88 vs. 74%) and d 14 (80 vs. 60%). It was concluded that treatment of anestrous cows before the start of breeding resulted in earlier conception than no treatment but had no effect on the final pregnancy rate. The addition of P4 to the Ovsynch program resulted in earlier conception and in more cows with normal subsequent luteal-phase lengths.
S McDougall
Related Documents :
10734368 - Repeated endoscopic ovum pick-up in sheep.
10549958 - Cavaterm thermal balloon ablation for the treatment of menorrhagia.
18922518 - Tolerability, side effects, and complications of hysterosalpingocontrast sonography (hy...
7359288 - Experience with the copper 7 intrauterine device in an adolescent population.
8976228 - Combined modified rectus fascial sling and augmentation ileocystoplasty for neurogenic ...
16083198 - Metastatic potentiality of micropapillary and conventional histological patterns: a com...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of dairy science     Volume:  93     ISSN:  1525-3198     ISO Abbreviation:  J. Dairy Sci.     Publication Date:  2010 May 
Date Detail:
Created Date:  2010-04-23     Completed Date:  2010-10-20     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  2985126R     Medline TA:  J Dairy Sci     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1944-59     Citation Subset:  IM    
Copyright Information:
Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Animal Health Centre, PO Box 21, Morrinsville, New Zealand, 3300.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Abortion, Veterinary
Anestrus / drug effects*
Estrus / drug effects
Fertilization / drug effects
Gonadotropin-Releasing Hormone / pharmacology*
Hormones / pharmacology*
Milk / chemistry
Pregnancy Rate
Progesterone / pharmacology*
Prostaglandins / analysis,  pharmacology*
Time Factors
Reg. No./Substance:
0/Hormones; 0/Prostaglandins; 33515-09-2/Gonadotropin-Releasing Hormone; 57-83-0/Progesterone

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  In vitro and in vivo analysis of fatty acid effects on metabolism of 17beta-estradiol and progestero...
Next Document:  Efficacy of enrofloxacin in the treatment of naturally occurring acute clinical Escherichia coli mas...