title: Dynamics of Progesterone, TNF- α , and a Metabolite of PGF2 α in Blood Plasma of Beef Cows following Embryo Transfer.
abstract: Lactating beef cows previously synchronized for estrus (d 0) were assigned to four treatments to assess their effectiveness in increasing blood progesterone (P4) and its effects on tumor necrosis factor-α (TNF-α) and prostaglandin F2α (PGF2α) after the transfer of embryos. At the time of transfer (d 7), cows received no treatment (control; n = 16), a controlled internal drug releasing device (CIDR; n = 16), human chorionic gonadotropin (hCG; n = 15), or gonadotropin releasing hormone (GnRH; n = 15). Blood samples were taken on d 7, 14, and 21 for analysis of P4 and tumor necrosis factor-α (TNF-α). Blood was collected (every 15 min for 2 h) in half the animals in each treatment group on d 14 and the remaining half on d 21 for analysis of prostaglandin F2α metabolite (PGFM). Retention rates were 56.2, 62.5, 46.7, and 13.3% for cows in the control, CIDR, hCG, and GnRH groups, respectively. Progesterone was greater (P ≤ 0.05) in cows receiving hCG compared to others on d 14. Progesterone in all treatment groups increased from d 7 to d 14 and declined (P ≤ 0.05) from d 14 to d 21. Contrary to pregnant cows, P4 and TNF-α declined from d 7 to d 21 in nonpregnant cows (P ≤ 0.05). Although PGFM increased by d 21, there was no difference between pregnant and nonpregnant cows.
authors.affiliation: Department of Agriculture, Alcorn State University, 1000 ASU Drive No. 750, Alcorn State, Lorman, MS 39096, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Mason
authors.affiliation: Department of Agriculture, Alcorn State University, 1000 ASU Drive No. 750, Alcorn State, Lorman, MS 39096, USA.
authors.forename: J
authors.initials: J
authors.lastname: Copeland
authors.affiliation: Department of Agriculture, Alcorn State University, 1000 ASU Drive No. 750, Alcorn State, Lorman, MS 39096, USA.
authors.forename: E J
authors.initials: EJ
authors.lastname: Cuadra
authors.affiliation: Bovine Functional Genomics Laboratory Beltsville Agricultural Center, USDA ARS, Beltsville, MD 20705, USA.
authors.forename: T H
authors.initials: TH
authors.lastname: Elsasser
authors.affiliation: Cooperative Agricultural Research Center, Prairie View A&M University, P.O. Box 519, AGRL No. 112, Prairie View, TX, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Department of Animal and Dairy Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: J
authors.initials: J
authors.lastname: Larson