A5074148509- Reproductive Physiology in Livestock
- Reproductive Biology and Fertility
- Plant and fungal interactions
- Genetic and phenotypic traits in livestock
- Ruminant Nutrition and Digestive Physiology
- Botanical Research and Chemistry
- Turfgrass Adaptation and Management
- Plant Toxicity and Pharmacological Properties
- Effects of Environmental Stressors on Livestock
- Sperm and Testicular Function
- Reproductive System and Pregnancy
- Ovarian function and disorders
- Animal Genetics and Reproduction
- Animal Behavior and Welfare Studies
- Animal Nutrition and Physiology
- Plant Reproductive Biology
- Milk Quality and Mastitis in Dairy Cows
- Animal health and immunology
- Estrogen and related hormone effects
- Pluripotent Stem Cells Research
- Plant Taxonomy and Phylogenetics
- Veterinary Equine Medical Research
- Renal and related cancers
- Nutrition, Health and Food Behavior
- Plant Genetic and Mutation Studies
University of Tennessee at Knoxville
2016-2025
Clemson University
1990-2012
Agricultural Research Service
2012
Archer Daniels Midland (United States)
2010
Arkansas Agricultural Experiment Station
2007
West Virginia University
1992-1998
Low doses of progestogens in regimens for synchronization estrus result persistent follicles (PF) and reduced conception rates cattle. The effects PF on recovery oocytes/embryos, fertilization, embryonic development were examined beef cows. To produce PF, cows received a used Controlled Internal Drug Releasing device Days 4 through 13 after pretreatment (Day 0) two injections 20 mg prostaglandin (PG) F2α, i.m., 12 h apart Day 6 (PF; n = 20). Control only PGF2α so they would ovulate growing...
The development of ovarian follicular and luteal structures during the estrous cycle early pregnancy in ewes was examined. Ewes were treated with prostaglandin F2 alpha to induce estrus; they placed either two fertile or vasectomized rams observed for estrus twice daily. Beginning at (Day 0), ovaries scanned CL follicles > = 2 mm by transrectal ultrasonography daily first 25 days (PREG, n 17 ewes) until Day 8 second (CYC, 15 ewes). Jugular blood samples collected on Days 30, 35, 40 gestation...
We determined whether a fixed-time AI (TAI) protocol could yield pregnancy rates similar to requiring detection of estrus, or estrous plus TAI, and adding controlled internal device release (CIDR) GnRH-based protocols would enhance fertility. Estrus was synchronized in 2,598 suckled beef cows at 14 locations, preceded by 1 5 treatments: 1) CIDR for 7 d with 25 mg PG F2α (PGF) removal, followed estrus during the 84 h after PGF; not detected received 100 μg GnRH TAI (control; n = 506); 2)...
Color Doppler ultrasonography was used to compare blood flow characteristics in the caudal artery of heifers fed diets with endophyte (Neotyphodium coenophialum) infected (E+) or noninfected (E-) tall fescue seed. Eighteen crossbred (Angus x Brangus) were assigned 6 pens and chopped alfalfa hay for 5 d plus a concentrate that contained E-tall seed 9 during an adjustment period. An 11-d experimental period followed, animals 3 E+ those other E E- ultrasound measurements (caudal area, peak...
Elevated body temperature (HEAT) in sexually receptive females is a normal part of the periovulatory microenvironment. The objective was to identify direct (first 6 h) and delayed (4 h or 18 recovery) effects at 41 °C exposure during vitro maturation (IVM) on transcripts involved steroidogenesis, oocyte maturation, previously impacted by elevated using targeted RNA-sequencing. Most (72.3%) were first 2 4 hIVM. Twelve fifteen hIVM had higher abundance three lower abundance. Direct related...
Four experiments were designed to examine the contribution of oocyte or follicular, oviductal, early uterine environments low fertility associated with first ovulation postpartum. At 17–25 days postpartum in 1, 2, and 3, suckled beef cows assigned at random receive 6 mg norgestomet, via ear-implant, for 9 (NOR) serve as controls (CON). Calves weaned from all 7 after assignment treatment order induce estrus, an LH surge, ovulation, subsequent formation CL. As detected be they bred by natural...
Doppler ultrasonography was used to compare blood flow characteristics in the caudal artery of heifers fed diets with endophyte (Neotyphodium coenophialum) noninfected (E−, 0 μg ergovaline/g DM), a 1:1 mixture endophyte-infected and E− (E+E−; 0.39 or (E+, 0.79 DM) tall fescue (Lolium arundinaceum) seed. Eighteen crossbred (Angus × Brangus) [345 ± 19 kg (SD)] were assigned individual pens chopped alfalfa hay plus concentrate that contained seed for 7 d during an adjustment period. A 9-d...
When the effects of heat stress are detrimental during maturation, cumulus cells intimately associated with oocyte. To determine extent to which affects these cells, in this study, transcriptome profiles that surrounded control and heat-stressed oocytes (41 °C first 12 h only then shifted back 38.5 °C) vitro maturation (IVM) were compared using Affymetrix bovine microarrays. The comparison cumulus-derived revealed a number transcripts whose levels increased ( n =11) or decreased =13) ≥...
An experiment was conducted to determine if ergot alkaloids affect blood flow the absorptive surface of rumen. Steers (n=8) were pair-fed alfalfa cubes and received ground endophyte-infected (Neotyphodium coenophialum) tall fescue (Lolium arundinaceum; E+) seed (0.015 mg ergovaline·kg BW(-1)·d(-1)) or endophyte-free (E-) via rumen cannula 2x daily for 7 d at thermoneutral (TN; 22°C) heat stress (HS; 32°C) conditions. On 8, emptied rinsed. A buffer containing VFA incubated in following...
Survival rate of embryos from first ovulations postpartum cows with SHORT (6.9 ± 0.3 days; n = 35) or NORMAL (17.1 42) luteal phases and quality the on Day 6 were compared. At 19 to 23 days postpartum, allotted receive a norgestomet implant for 9 (normal phase) serve as untreated controls (short phase). Calves weaned 7 after initiation treatment induce behavioral estrus in mating. In 25 cows, growth ovulatory follicle was monitored by ultrasonography. On estrus, recovered nonsurgically, live...
Abstract Retinol (vitamin A) is essential for reproduction, and retinoids have been suggested to play a role in ovarian steroidogenesis, oocyte maturation, early embryonic development. transported systemically intercellularly by retinol‐binding protein (RBP). Within the cell, cellular (CRBP) functions retinol accumulation metabolism. Since actions of are mediated, part, retinoid‐binding proteins, objective this study was investigate cell‐specific expression RBP CRBP bovine ovary....
Previous research has indicated that serotonergic and α-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+; Epichlöe coenophialia) tall fescue (Lolium arundinaceum). The objective this experiment was to determine the period time necessary for vascular effects ergot alkaloids subside. Two experiments were conducted investigate changes contractile response vasoconstriction over relative removal from an alkaloid-containing E+...