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The Comparison of Treating Holstein Dairy Cows with Progesterone, CIDR and GnRH After Insemination on Serum Progesterone and Pregnancy Rates
Author(s) -
Mehni SB,
Shabankareh HK,
KazemiBonchenari M,
Eghbali M
Publication year - 2012
Publication title -
reproduction in domestic animals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.546
H-Index - 66
eISSN - 1439-0531
pISSN - 0936-6768
DOI - 10.1111/j.1439-0531.2011.01811.x
Subject(s) - artificial insemination , endocrinology , medicine , pregnancy , insemination , pregnancy rate , gonadotropin releasing hormone , zoology , hormone , biology , andrology , luteinizing hormone , sperm , genetics
Contents This experiment was conducted to investigate the effects of different exogenous progesterone sources administrated after artificial insemination (AI) on serum progesterone (P 4 ) concentration and pregnancy rates in Holstein lactating cows. Sixty‐four lactating Holstein dairy cows were allocated to four different treatments (n = 16 per treatment): the cows 1) were injected with physiological saline on days 5 and 13 after AI (control group); 2) were injected with progesterone on days 5 and 13 after AI (P group); 3) received controlled internal drug releasing device (CIDR) for a period from day 5 to 19 after AI (CIDR group); and 4) were injected with gonadotropin‐releasing hormone (GnRH) agonist on days 5 and 13 after AI (GnRH group). Blood samples were collected on days 0 (AI day), 5, 13, 16 and 19 after AI to determine serum P 4 concentration. The results revealed a significant difference among treatment groups for serum P 4 concentration on days 13, 16 and 19 with the lowest concentration of serum P 4 for the control group. The pregnancy rate was also positively affected by all the treatments with CIDR having the greatest effect on pregnancy rate. Overall, the results indicated that CIDR has the greatest effect on serum P 4 concentration and pregnancy rate, although the administration of P and GnRH during days after AI increased serum P 4 concentration in lactating dairy cows as well.