The Experts below are selected from a list of 63 Experts worldwide ranked by ideXlab platform
Stevenson, Jeffrey S. - One of the best experts on this subject based on the ideXlab platform.
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Luteolysis and pregnancy outcomes in dairy cows after treatment with estrumate or lutalyse
'New Prairie Press', 2009Co-Authors: Stevenson, Jeffrey S.Abstract:In Experiment 1, lactating dairy cows (n = 1,230) in 6 herds were treated with 2 injections of prostaglandin F2α(PGF2α) 14 days apart (Presynch), with the second injection administered 12 to 14 days before the onset of a timed AI protocol (Ovsynch). Cows were inseminated when detected in estrus after the Presynch PGF2αinjections. Cows not inseminated were enrolled in the Ovsynch protocol and were assigned randomly to be treated with either Estrumate or Lutalyse as part of a timed artificial insemination (AI) protocol. Blood samples were collected before treatment injection (0 hour) and 48 and 72 hours later. In cows having progesterone concentrations ≥1 ng/mL at 0 hour and potentially having a functional corpus luteum (CL) responsive to a Luteolytic Agent, Lutalyse increased (P \u3c 0.05) luteal regression from 83.9 to 89.3%. Despite a significant increase in luteolysis, pregnancy rate per AI did not differ between treatments. Fertility was improved in both treatments in cows having reduced progesterone concentrations at 72 hours and in those showing signs of estrus. In Experiment 2, an ovulation resynchronization (Ovsynch-Resynch) program was initiated with gonadotropin-releasing hormone (GnRH) or saline in 427 previously inseminated lactating dairy cows of unknown pregnancy status in 1 herd. Seven days later, pregnancy was diagnosed and nonpregnant cows were blocked by number of CL and assigned randomly to receive Estrumate or Lutalyse. Diameter of each CL was recorded and blood samples were collected at 0 and 72 hours after treatment to assess serum progesterone. A fixed-time AI was given at 72 hours after treatment and approximately 16 hours after a GnRH injection to induce ovulation. Lutalyse increased(P \u3c 0.05) luteal regression from 69.1 to 78.5% regardless of the number of CL present or the total luteal volume per cow exposed to treatment. Pregnancy rate per AI did not differ between treatments. Although Lutalyse was slightly more effective than Estrumate in inducing luteolysis in lactating dairy cows exposed to an Ovsynch or Ovsynch-Resynch protocol, resulting pregnancy outcomes did not differ between products.; Dairy Day, 2009, Kansas State University, Manhattan, KS, 2009; Dairy Research, 2009 is known as Dairy Day, 200
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Luteolysis and pregnancy outcomes in dairy cows after treatment with estrumate or lutalyse
Kansas State University. Agricultural Experiment Station and Cooperative Extension Service, 2009Co-Authors: Stevenson, Jeffrey S.Abstract:Dairy Research, 2009 is known as Dairy Day, 2009In Experiment 1, lactating dairy cows (n = 1,230) in 6 herds were treated with 2 injections of prostaglandin F2α (PGF2α) 14 days apart (Presynch), with the second injection administered 12 to 14 days before the onset of a timed AI protocol (Ovsynch). Cows were inseminated when detected in estrus after the Presynch PGF2α injections. Cows not inseminated were enrolled in the Ovsynch protocol and were assigned randomly to be treated with either Estrumate or Lutalyse as part of a timed artificial insemination (AI) protocol. Blood samples were collected before treatment injection (0 hour) and 48 and 72 hours later. In cows having progesterone concentrations ≥1 ng/mL at 0 hour and potentially having a functional corpus luteum (CL) responsive to a Luteolytic Agent, Lutalyse increased (P < 0.05) luteal regression from 83.9 to 89.3%. Despite a significant increase in luteolysis, pregnancy rate per AI did not differ between treatments. Fertility was improved in both treatments in cows having reduced progesterone concentrations at 72 hours and in those showing signs of estrus. In Experiment 2, an ovulation resynchronization (Ovsynch-Resynch) program was initiated with gonadotropin-releasing hormone (GnRH) or saline in 427 previously inseminated lactating dairy cows of unknown pregnancy status in 1 herd. Seven days later, pregnancy was diagnosed and nonpregnant cows were blocked by number of CL and assigned randomly to receive Estrumate or Lutalyse. Diameter of each CL was recorded and blood samples were collected at 0 and 72 hours after treatment to assess serum progesterone. A fixed-time AI was given at 72 hours after treatment and approximately 16 hours after a GnRH injection to induce ovulation. Lutalyse increased(P < 0.05) luteal regression from 69.1 to 78.5% regardless of the number of CL present or the total luteal volume per cow exposed to treatment. Pregnancy rate per AI did not differ between treatments. Although Lutalyse was slightly more effective than Estrumate in inducing luteolysis in lactating dairy cows exposed to an Ovsynch or Ovsynch-Resynch protocol, resulting pregnancy outcomes did not differ between products
Bo R Rueda - One of the best experts on this subject based on the ideXlab platform.
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Mutant mouse models and their contribution to our knowledge of corpus luteum development, function and regression
Reproductive Biology and Endocrinology, 2003Co-Authors: Luiz E Henkes, John S Davis, Bo R RuedaAbstract:The corpus luteum is a unique organ, which is transitory in nature. The development, maintenance and regression of the corpus luteum are regulated by endocrine, paracrine and autocrine signaling events. Defining the specific mediators of luteal development, maintenance and regression has been difficult and often perplexing due to the complexity that stems from the variety of cell types that make up the luteal tissue. Moreover, some regulators may serve dual functions as a luteotropic and Luteolytic Agent depending on the temporal and spatial environment in which they are expressed. As a result, some confusion is present in the interpretation of in vitro and in vivo studies. More recently investigators have utilized mutant mouse models to define the functional significance of specific gene products. The goal of this mini-review is to identify and discuss mutant mouse models that have luteal anomalies, which may provide some clues as to the significance of specific regulators of corpus luteum function.
Juan A Garciavelasco - One of the best experts on this subject based on the ideXlab platform.
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avoiding ovarian hyperstimulation syndrome with the use of gonadotropin releasing hormone agonist trigger
Fertility and Sterility, 2015Co-Authors: Human M Fatemi, Juan A GarciavelascoAbstract:Ovarian hyperstimulation syndrome (OHSS) is one of the most serious, and potentially lethal, complications of controlled ovarian stimulation (COS). Induction of final oocyte maturation with a bolus of gonadotropin-releasing hormone (GnRH) agonist (GnRHa), instead of the criterion standard hCG, in patients undergoing ovarian stimulation significantly reduces the risk of OHSS and could be considered to be more physiologic. A bolus of GnRHa used in this context also acts as a Luteolytic Agent. From a clinical point of view, the most significant benefit of GnRHa trigger is its ability to induce quick and reversible luteolysis and thus reducing the risk of OHSS development. This paper describes the pathophysiology of OHSS, focusing specifically on the Luteolytic benefits of using GnRHa to decrease OHSS and the possible corpus luteum rescue modalities available.
R M Roberts - One of the best experts on this subject based on the ideXlab platform.
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a comparison of the anti Luteolytic activities of recombinant ovine interferon alpha and tau in sheep
Biology of Reproduction, 2005Co-Authors: Mark P Green, Lee D Spate, James A Bixby, Alan D Ealy, R M RobertsAbstract:Interferon tau (IFNT) is secreted by the trophectoderm of ruminant conceptuses during the peri-implantation period and serves an anti-Luteolytic function. The question as to whether IFNT is superior as an anti-Luteolytic Agent to closely related Type I IFNs, such as IFN alpha (IFNA), which have a different function, remains unanswered. Thus, the aim of this study was to determine whether equivalent antiviral (AV) units of ovIFNA and ovIFNT are equipotent in extending estrous cycle length. Four distinct ovIFNA mRNA (ovIFNA1–4) were cloned from ovine lymphocytes. Recombinant ovine IFNs (ovIFNT4 and ovIFNA1) were prepared in the yeast Pichia pastoris. The AV activity of the purified IFNs was determined on a bovine cell line (MDBK) and on transformed ovine luminal uterine epithelial cells. Indwelling uterine catheters were fitted into crossbred ewes on Day 3 postestrus (Day 0 ¼estrus). Between Days 10 and 18 postestrus, ewes received twice-daily infusions of 0.7 3 10 7 IU of either ovIFNA1 or T4, plus serum albumin. Control ewes received serum albumin only. Daily blood samples were collected for progesterone determination, and ewes were monitored twice daily for estrus. Both ovIFNA (P ¼ 0.04) and ovIFNT (P ¼ 0.01) caused estrous cycle extension in nonpregnant ewes compared to controls when administered at equivalent AV doses. In conclusion, the uniqueness of IFNT as an anti-Luteolytic Agent most likely resides in its unique expression pattern rather than its special biopotency. conceptus, corpus luteum, endometrium, estrous cycle, pregnancy, progesterone, trophoblast
Luiz E Henkes - One of the best experts on this subject based on the ideXlab platform.
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Mutant mouse models and their contribution to our knowledge of corpus luteum development, function and regression
Reproductive Biology and Endocrinology, 2003Co-Authors: Luiz E Henkes, John S Davis, Bo R RuedaAbstract:The corpus luteum is a unique organ, which is transitory in nature. The development, maintenance and regression of the corpus luteum are regulated by endocrine, paracrine and autocrine signaling events. Defining the specific mediators of luteal development, maintenance and regression has been difficult and often perplexing due to the complexity that stems from the variety of cell types that make up the luteal tissue. Moreover, some regulators may serve dual functions as a luteotropic and Luteolytic Agent depending on the temporal and spatial environment in which they are expressed. As a result, some confusion is present in the interpretation of in vitro and in vivo studies. More recently investigators have utilized mutant mouse models to define the functional significance of specific gene products. The goal of this mini-review is to identify and discuss mutant mouse models that have luteal anomalies, which may provide some clues as to the significance of specific regulators of corpus luteum function.
