THE USE OF PROSTAGLANDIN F2α IN NATURALLY BRED BEEF HEIFERS

1988 ◽  
Vol 68 (4) ◽  
pp. 1301-1304 ◽  
Author(s):  
R. D. H. COHEN ◽  
B. D. KING ◽  
E. D. JANZEN
Keyword(s):  
Key Words ◽  
Prostaglandin F2α ◽  
Estrus Synchronization ◽  
Beef Heifers ◽  
Conception Rates ◽  
Prostaglandin F ◽  
Natural Breeding

Heifers injected with prostaglandin F2α had significantly higher pregnancy and conception rates within 11 d of start of breeding than noninjected heifers; 56.9 vs. 45.5 pregnancy as a percent of heifers exposed (P < 0.05) and 74.1 vs. 58.2 conception as a percent of pregnant heifers (P < 0.005). Data were pooled for 422 heifers over 5 yr. However, there were no significant effects on calving distribution or weaning weights of their calves. Key words: Prostaglandin F2α, natural breeding, heifer, estrus synchronization

A comparison of two estrus synchronization methods in beef heifers

1998 ◽  
Vol 78 (3) ◽  
pp. 437-439
Author(s):  
L. A. Stephens ◽  
R. Rajamahendran
Keyword(s):  
Key Words ◽  
Pregnancy Rate ◽  
Gonadotropin Releasing Hormone ◽  
Estrus Synchronization ◽  
Beef Heifers ◽  
Releasing Hormone ◽  
Prostaglandin F

This study compared the use of two injections of prostaglandin F2α(PGF2α) given 11 d apart with the use of gonadotropin releasing hormone (GnRH) followed by PGF2α after 7 d for synchronizing estrus in beef heifers. Heifers synchronized with GnRH and PGF2α showed weak signs of estrus and were more difficult to inseminate. There were no significant differences in synchronization rate and pregnancy rate. Key words: Estrus synchronization, beef heifers, gonadotropin releasing hormone, prostaglandin F2α

scholarly journals 386 Efficacy of a Second Injection of Prostaglandin F2α in Yearling Beef Heifers Following Previous Estrus Synchronization.

2018 ◽  
Vol 96 (suppl_2) ◽  
pp. 207-208
Author(s):  
M Erickson ◽  
K C Ramsay ◽  
R N Funston
Keyword(s):  
Prostaglandin F2α ◽  
Estrus Synchronization ◽  
Beef Heifers

Conception Rates in Beef Heifers at Four Time Intervals After Prostaglandin F2α

2001 ◽  
Vol 17 (3) ◽  
pp. 191-194
Author(s):  
L.R. Sprott ◽  
R.S. Walker ◽  
S.W. Wikse ◽  
D.W. Forrest
Keyword(s):  
Prostaglandin F2α ◽  
Beef Heifers ◽  
Time Intervals ◽  
Conception Rates

Comparison of Melengestrol Acetate-Prostaglandin F2α to Syncro-Mate B for estrus synchronization in beef heifers

1988 ◽  
Vol 30 (1) ◽  
pp. 1-12 ◽  
Author(s):  
L.N. Brown ◽  
K.G. Odde ◽  
M.E. King ◽  
D.G. LeFever ◽  
C.J. Neubauer
Keyword(s):  
Prostaglandin F2α ◽  
Estrus Synchronization ◽  
Beef Heifers ◽  
Melengestrol Acetate

Melengestrol acetate, estradiol-17β and GnRH for synchronization of estrus and ovulation in beef cows

1999 ◽  
Vol 79 (1) ◽  
pp. 39-43 ◽  
Author(s):  
J. Thundathil ◽  
J. P. Kastelic ◽  
W. O. Olson ◽  
R. B. Cook ◽  
R. J. Mapletoft
Keyword(s):  
Key Words ◽  
Pregnancy Rate ◽  
Beef Cows ◽  
Pregnancy Rates ◽  
Conception Rate ◽  
Estrus Synchronization ◽  
Short Term ◽  
Melengestrol Acetate ◽  
Conception Rates ◽  
Estradiol 17Β

Three experiments were conducted with suckled crossbred beef cows to determine the efficacy of various short-term regimens for synchronizing estrus or ovulation and to determine whether feeding melengestrol acetate (MGA) after timed AI will increase pregnancy rate. In exp. 1, all cows (n = 141) were given 0.5 mg MGA head−1 d−1 for 7 d (days 1 to 7), 1 or 5 mg E17β (and 100 mg progesterone) or 100 µg GnRH on day 1, and 500 µg cloprostenol on day 7. There were no significant differences among groups for estrous or synchronized conception rates (average, 84.4 and 52.1%, respectively). With an identical protocol in exp. 2 (78 cows), by day 11, cows given 5 mg E17β had the highest estrous and synchronized pregnancy rates (65.4 and 42.3%), compared to 1 mg E17β (46.2 and 15.4%) and GnRH (34.6 and 11.5%). Cows not detected in estrus were timed-inseminated and given 100 µg GnRH, 100 h after cloprostenol. There were no significant differences among groups for synchronized conception rate to timed AI (65.0%) or synchronized pregnancy rate to all inseminations (56.4%). Overall, 5 mg E17β gave the most consistent results. In exp. 3, 84 cows were given 100 µg GnRH on days 1 and 9, 500 µg cloprostenol on day 7, and were timed-inseminated on day 10. Half were fed MGA (0.5 mg head−1 d−1) on days 16 to 22, but the pregnancy rate was not different from that in the remaining cows (55.0 versus 47.8%, P > 0.5). Key words: Ovary, follicles, estrus synchronization, beef cows

Comparaison de l'effet de deux analogues de la prostaglandine F2α sur la synchronisation de l'œstrus chez la vache de boucherie

1994 ◽  
Vol 74 (1) ◽  
pp. 29-36 ◽  
Author(s):  
G. Laverdière ◽  
J. J. Dufour ◽  
G. L. Roy ◽  
D. Lavoie ◽  
J. Proulx
Keyword(s):  
Beef Cattle ◽  
Key Words ◽  
Fertility Rate ◽  
Pregnancy Rates ◽  
Estrus Synchronization ◽  
Fertility Rates ◽  
Prostaglandin F

The objective of this study was to compare the efficiency of cloprostenol and fenprostalene in synchronizing estrus. Before treatment, estrus was detected during 4.5 d for multiparous cows in exp. 1 (n = 105) and 7.5 d for primiparous and nulliparous females in exp. 2 (n = 86). Females that were not in estrus (exp. 1: n = 74 and exp. 2: n = 58) received at random, either 500 μg of cloprostenol (i.m.) or 1 mg of fenprostalene (s.c). Cattle synchronized with cloprostenol or fenprostalene that presented estrus within 5 d showed similar fertility rates (exp. 1: 86.1% vs. 88.0% and exp. 2: 89.3% vs. 72.2% for cloprostenol and fenprostalene, respectively) and PGF2α-estrus intervals (exp. 1: 68 h vs. 73 h and exp. 2: 57 h vs. 57 h). However, the incidence of synchronization (exp. 1: 97.3% vs. 67.6%, P < 0.001; and exp. 2: 93.3% vs. 64.3%, P < 0.01) and pregnancy rates (exp. 1: 83.8% vs. 59.5%, P < 0.05; and exp. 2: 83.3% vs. 46.4%, P < 0.01) were statistically higher for cloprostenol than for fenprostalene. In exp. 2, primiparous cows and heifers obtained similar reproductive performances. The fertility rate of cattle treated with cloprostenol in exp. 2 was higher than that of untreated cattle (89.3% vs. 50.0%, P < 0.001, n = 56). In exp. 1, the variance of interval to estrus was similar for both analogues, but in exp. 2, it was less variable after the administration of cloprostenol (P < 0.05). Intervals between cloprostenol injection and estrus (0–10 and 0–15 d) were shorter (P < 0.05) and less variable (P < 0.001) than fenprostalene–estrus intervals. These results indicate that cloprostenol has a better potential for estrus synchronization than fenprostalene. Key words: Cloprostenol, fenprostalene, estrus synchronization, prostaglandin F2α, beef cattle

Estrus synchronization systems involving prostaglandin F2α and progesterone pretreatment in beef heifers

1986 ◽  
Vol 25 (2) ◽  
pp. 249-261 ◽  
Author(s):  
C.K. Higgins ◽  
J.G. Berardinelli ◽  
D.K. Han ◽  
R.P. Ansotegui ◽  
E.L. Moody
Keyword(s):  
Prostaglandin F2α ◽  
Estrus Synchronization ◽  
Beef Heifers

THE EFFECTS OF TIME OF INSEMINATION ON FERTILITY IN BEEF HEIFERS SYNCHRONIZED WITH PROSTAGLANDIN F2α

1977 ◽  
Vol 57 (1) ◽  
pp. 47-51 ◽  
Author(s):  
J. G. MANNS ◽  
M. S. WENKOFF ◽  
W. M. ADAMS ◽  
G. RICHARDSON
Keyword(s):  
Prostaglandin F2α ◽  
Corpora Lutea ◽  
Beef Heifers ◽  
Serum Progesterone ◽  
Group 4 ◽  
Prostaglandin F ◽  
Group 3 ◽  
Group 2 ◽  
Observation Period ◽  
Group 1

Two injections of prostaglandin F2α (PGF2α) spaced 12 days apart were used to synchronize estrus in Hereford heifers. Animals were inseminated at 75 h (group 2), 80 h (group 3) or 85 h (group 4) after the second injection of PGF2α. Untreated control animals (group 1) were inseminated as detected in estrus over an observation period of approximately 35 days. Immediately before, and 24 h after each PGF2α injection, blood was collected for progesterone assay. Fertility expressed as calving rates was as follows: group 1, 33/77 (43%); group 2, 30/79 (38%); group 3, 29/79 (37%); group 4, 20/73 (27%). Fertility was depressed at 85 h vs. control (P < 0.05) in PGF2α-treated animals but there were no other significant differences. Progesterone assays showed that 65% of animals had progesterone-secreting corpora lutea at the first injection of PGF2α. There was no relationship between fertility and either serum progesterone concentration or the day of the cycle at the second injection of PGF2α.

scholarly journals Estrus synchronization of replacement beef heifers by using GnRH, prostaglandin F2α (PGF), and progesterone (CIDR): a multi-location study

2004 ◽  
pp. 3-6
Author(s):  
J.E. Larson ◽  
G.C. Lamb ◽  
T.W. Geary ◽  
Jeffrey S. Stevenson ◽  
Sandra K. Johnson ◽  
...  
Keyword(s):  
Prostaglandin F2α ◽  
Estrus Synchronization ◽  
Beef Heifers ◽  
Location Study
Sign in / Sign up

Export Citation Format

Share Document