The role of omega-3 polyunsaturated fatty acids in reproduction of sheep and cattle

Animal Reproduction Science, Journal Year: 2012, Volume and Issue: 131(1-2), P. 9 - 22

Published: Feb. 11, 2012

Language: Английский

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Effect of level of dietary n-3 polyunsaturated fatty acid supplementation on systemic and tissue fatty acid concentrations and on selected reproductive variables in cattle

Theriogenology, Journal Year: 2008, Volume and Issue: 70(4), P. 595 - 611

Published: June 3, 2008

Language: Английский

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Role of Follicular Estradiol-17beta in Timing of Luteolysis in Heifers1

Biology of Reproduction, Journal Year: 2009, Volume and Issue: 81(2), P. 426 - 437

Published: March 4, 2009

The hypothesis was tested that estradiol (E2) from the ovarian follicles controls time of luteolysis. Time luteolysis evaluated by multiple measures corpus luteum (CL) structure (area, volume) and function (progesterone [P4], luteal blood flow). for experiment 1 repeated ablation would reduce circulating E2 delay Heifers were randomly assigned on Day 9 (Day 0 = ovulation) to three groups. All >or=4 mm ablated (group FA9; n 6); Days 9-15 FA15; or 9-21 FA21; 7). As expected, follicular delayed (P < 0.001) rise in peak concentrations (FA9, 17.6 +/- 0.7; FA15, 20.3 0.3; FA21, 24.9 0.3). Luteolysis (based each measure) 0.005) follicles, with earlier P4 decrease) FA9 15.2 0.8) than FA15 16.5 0.4), a further FA21 18.3 0.5). 2 exogenous treatment stimulate prostaglandin F(2alpha) (PGF) secretion prevent associated ablations. Follicles 17 (n 15). treated 13 15 1.0 mg benzoate (FAE2; 7) vehicle (FAV; 8). Treatment induced PGF (detected metabolite) 0.02) FAE2 FAV, whether determined area, volume, flow CL. In summary, (>or=4 mm) hastened heifers follicles. Thus, these results are consistent an essential role follicle timing

Language: Английский

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Effects of cloprostenol sodium at final prostaglandin F2α of Ovsynch on complete luteolysis and pregnancy per artificial insemination in lactating dairy cows

Journal of Dairy Science, Journal Year: 2011, Volume and Issue: 94(6), P. 2815 - 2824

Published: May 25, 2011

Language: Английский

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Necessity of Sequential Pulses of Prostaglandin F2alpha for Complete Physiologic Luteolysis in Cattle1

Biology of Reproduction, Journal Year: 2008, Volume and Issue: 80(4), P. 641 - 648

Published: Dec. 10, 2008

The luteolytic effects of exogenous prostaglandin F2alpha (PGF) that did and not simulate natural 13,14-dihydro-15-keto-PGF (PGFM) pulses were studied during mid-diestrus in 42 Holstein heifers. Plasma concentrations PGF assessed by assay PGFM. In experiment 1, a single intrauterine injection 4.0 mg into the uterine horn ipsilateral to corpus luteum resulted precipitous progesterone decline, whereas sequential injections 0.25 or 1.0 every 12 h stepwise decrease (P < 0.05) following each injection. A increase occurred first 5 min before but only for 4.0-mg dose. From results 2, 2-h infusion total 0.5 was judged best PGFM pulse. 3, simulation at 12-h intervals continuous <1 ng/ml beginning fourth simulated contrast, pulse 6-h constant concentration 3 days after treatment, followed return control concentrations. mean +/- SEM interval between pretreatment posttreatment ovulations shorter group with (14 1 day) than (21 day). Results indicated excessive doses may stimulate nonphysiologic responses supported hypothesis are required luteolysis cattle.

Language: Английский

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Patterns of late embryonic and fetal mortality and association with several factors in sheep1

Journal of Animal Science, Journal Year: 2007, Volume and Issue: 85(5), P. 1274 - 1284

Published: April 11, 2007

Embryonic and fetal mortality reduce lambing rates litter sizes, thus contributing to economic losses in the sheep industry. In current study, timing of late embryonic loss ewes factors with which these were associated examined. Ewes lambs born compared pregnancy diagnosis counts embryos by ultrasonography near d 25, 45, 65, or 85 gestation. Approximately 19.9% experienced loss, both; 21.2% fetuses lost from 25 term. Potential offspring throughout gestation; 3.7% 4.3% 45 3.3% 65 85, 11.5% parturition; thus, approximately 3 4% potential for each 20-d period beyond 25. A greater proportion one (36.7%) rather than all (20.5% single; 3.8% multiple) fetuses. The patterns similar mated during anestrous season transitional did not vary service within breeding method synchronization estrus. Late related temperature-humidity index. Maternal serum collected gestation was assayed concentrations progesterone, estradiol-17beta , vascular endothelial growth factor (VEGF). proportions breed type (P < 0.05), as progesterone 0.01), estradiol VEGF 0.01). relationships retention hormonal variables at 4 stages studied limited. Complete partial increased rapidly maternal decreased below 2 ng/mL 0.05). Survival a medium parturition high summary, occurred varied on

Language: Английский

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Novel insights into the mechanisms of pregnancy establishment: regulation of prostaglandin synthesis and signaling in the pig

Reproduction, Journal Year: 2011, Volume and Issue: 142(3), P. 389 - 399

Published: June 16, 2011

Ovarian progesterone induces essential changes leading to a temporary state of uterine receptivity for conceptus implantation. Estrogens secreted by the porcine on days 11 and 12 pregnancy provide initial signal maternal recognition maintenance functional corpus luteum (CL) continued production progesterone. As prostaglandins F(2)(α) (PGF(2)(α)) E(2) (PGE(2)) exert opposing actions CL, tight control over their synthesis secretion is critical either initiation luteolysis or pregnancy. One supportive mechanisms which inhibits changing PG in favor luteoprotective PGE(2). Conceptus PGE(2) could be amplified feedback loop endometrium. In pigs, as other species, implantation establishment associated with upregulation expression proinflammatory factors, include cytokines, growth lipid mediators. The produces inflammatory mediators: interferon γ δ, interleukins IL1B IL6, PGs, probably activate pathways endometrium responds these embryonic signals enhancing further progesterone-induced receptivity. Understanding required translational research increase reproductive efficiencies fertility humans animals.

Language: Английский

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Placental development during early pregnancy in sheep: vascular growth and expression of angiogenic factors in maternal placenta

Reproduction, Journal Year: 2010, Volume and Issue: 140(1), P. 165 - 174

Published: April 17, 2010

Placental vascular development (angiogenesis) is critical for placental function and thus normal embryonic/fetal growth development. Specific environmental factors or use of assisted reproductive techniques may result in poor angiogenesis, which contribute to embryonic losses and/or fetal retardation. Uterine tissues were collected on days 14, 16, 18, 20, 22, 24, 26, 28, 30 after mating day 10 estrus (nonpregnant controls) determine expression several involved the regulation angiogenesis endometrium. Compared with controls, measurements endometrial vascularity increased (P<0.001) including labeling index (LI; proportion proliferating cells), tissue area occupied by capillaries, per capillary (capillary size), total circumference unit area, factor VIII (marker endothelial but number decreased (P<0.001). mRNA factor, receptors, angiopoietins (ANGPT) 1 2, ANGPT receptor TEK, nitric oxide synthase, hypoxia-inducible 1alpha (P<0.05) during early pregnancy. Vascular LI was positively correlated angiogenic factors. These data indicate that manifested initiated very This more complete description provide foundation determining whether altered compromised pregnancies.

Language: Английский

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Novel concepts on the role of prostaglandins on luteal maintenance and maternal recognition and establishment of pregnancy in ruminants

Journal of Dairy Science, Journal Year: 2016, Volume and Issue: 99(7), P. 5926 - 5940

Published: May 11, 2016

Language: Английский

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The Immunology of Early Pregnancy in Farm Animals

Reproduction in Domestic Animals, Journal Year: 2011, Volume and Issue: 46(s3), P. 18 - 30

Published: Aug. 19, 2011

Contents The mammalian conceptus undergoes development in the face of a functional immune system. This characteristic viviparity creates opportunities and perils for conceptus. In period up to hatching from zona pellucida, appears immunologically inert with low expression major histocompatibility complex (MHC) genes little evidence alterations function maternal cells. may benefit cytokines produced by leucocytes resident reproductive tract or other cells tract. One cytokine particular, colony‐stimulating factor 2, can promote preimplantation cause changes that increase likelihood develops term. It is not clear whether activation specific types responses early pregnancy enhance success. Semen deposition causes inflammation tract, but there this process beneficial unless uterus was exposed prior inflammatory event. Around time placentation, immunological inertness replaced caused interferon ruminants pigs MHC class I invasive trophoblast horse. large‐scale endometrium occur as result are likely play an important role ensure continued contrast, generated disease tissues (mastitis) lead death Because hazard, well possibility cell‐mediated against could occur, system regulated both mother reduce responsiveness during pregnancy.

Language: Английский

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