Recent PublicationsView all

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we characterize the ability of the previously described Infoscitex tent (IST) to capture mosquitoes in comparison to either the Centers for Disease Control Light Trap hung next to individuals under a bed net (LTC) or to human landing catches (HLC). In Senegal, the IST caught 6.14 times the number of Anopheles gambiae sensu lato (s.l.), and 8.78 times the Culex group V mosquitoes as LTC. In one of two locations in Burkina Faso, the IST caught An. gambiae at a rate not significantly different than HLC. Of importance, 9.1-36.1% of HLC caught An. gambiae were blood fed, mostly with fresh blood, suggesting they fed upon the collector, whereas only 0.5-5.0% from the IST had partial or old blood. The IST also caught outdoor biting species in proportions comparable to HLC. The results show this tent provides a safer and effective alternative to the skill-dependent, risky, and laborious HLC method. ©The American Society of Tropical Medicine and Hygiene.
    Full-text · Article · Nov 2014 · The American journal of tropical medicine and hygiene
  • [Show abstract] [Hide abstract]
    ABSTRACT: In vitro fertilization (IVF) in horses is rarely successful. One reason for this could be failure of sperm to fully capacitate or exhibit hyper-active motility. We hypothesized that the zona pellucida (ZP) of equine oocytes prevents fertilization in vitro and bypassing the ZP would increase fertilization rates. Limited availability of equine oocytes for research has necessitated the use of heterologous oocyte binding assays using bovine oocytes. We sought to validate an assay using bovine oocytes and equine sperm, and then to demonstrate that bypassing the ZP using perivitelline sperm injections (PVI) with equine sperm capacitated with dilauroyl phosphatidylcholine (PC12) would result in higher fertilization rates than standard IVF in bovine and equine oocytes. In Experiment 1, bovine oocytes were used for: 1) IVF with bovine sperm, 2) IVF with equine sperm, and 3) intracytoplasmic sperm injections (ICSI) with equine sperm. Presumptive zygotes were either stained with 4',6-diamidino-2-phenylindole (DAPI) from 18 to 26 h at 2 h intervals or evaluated for cleavage 56 h following addition of sperm. Equine sperm fertilized bovine oocytes; however, pro-nuclei formation was delayed compared to bovine sperm after IVF. The delayed pro-nuclear formation was not seen following ICSI. In Experiment 2, bovine oocytes were assigned to five groups: 1) cumulus oocyte complexes (COC) co-incubated with bovine sperm, 2) COC exposed to sucrose then co-incubated with bovine sperm, 3) COC co-incubated with equine sperm, 4) COC exposed to sucrose and co-incubated with equine sperm, and 5) oocytes exposed to sucrose and 10 to 15 equine sperm injected into the perivitelline (PV) space. Equine sperm tended (P=0.08) to fertilize more bovine oocytes when injected into the PV space than after IVF. In Experiment 3, oocytes were assigned to four groups: 1) IVF, equine and bovine COC co-incubated with equine sperm, 2) PVI of equine and bovine oocytes, 3) PVI with equine oocytes pretreated with sucrose, and 4) ICSI of equine oocytes. Oocytes were examined at 24h for cleavage. No equine oocytes cleaved after IVF or PVI. However, ICSI conducted with equine sperm treated with PC12 resulted in 85% of the oocytes cleaving. Sperm injected into the PV space of equine oocytes did not appear to enter the ooplasm. This study validated the use of bovine oocytes for equine sperm studies and indicates that failure of equine IVF is more than an inability of equine sperm to penetrate the ZP.
    No preview · Article · Jul 2014 · Theriogenology
  • [Show abstract] [Hide abstract]
    ABSTRACT: In 2050, beef likely will be produced much as occurs currently, as (1) a by-product of dairying—cull cows and calves not needed as replacements; (2) intensively managed cattle in environments rich in feed resources; or (3) extensively managed cattle grazing land unsuitable for tillage, with calves often moving to richer feed environments. Genetic progress will continue to depend on information such as weaning weights, but in addition, genetic, epigenetic, and phenotypic information will be obtained from blood, hair, semen, and/or biopsies of embryos. Most cattle will be genetically modified for efficient growth, desirable carcass traits, and management traits such as disease resistance. Some strains of cattle will have Y-chromosome-dependent terminal cross traits; sexed semen thus will automatically result in males with terminal cross characteristics and females with maternally desirable traits. In most cases, mother cows will have shorter gestations and smaller frame sizes than currently to decrease nutrient requirements for maintenance. The cow herd may disappear with some intensively managed systems; with sexed semen, each female can replace herself with a female calf and then be fattened for slaughter. The flexibility of being a ruminant will continue to be exploited by using a variety of feedstuffs, some of which are otherwise of little value.
    No preview · Article · Jan 2014 · Advances in Experimental Medicine and Biology
Information provided on this web page is aggregated encyclopedic and bibliographical information relating to the named institution. Information provided is not approved by the institution itself. The institution’s logo (and/or other graphical identification, such as a coat of arms) is used only to identify the institution in a nominal way. Under certain jurisdictions it may be property of the institution.