Publications

seroprevalence of bovine anaplasmosis in oklahoma from 1977 to 1991.	the prevalence of anaplasmosis in oklahoma cattle was determined on the basis of the standardized anaplasma marginale complement fixation test on 20,155 sera submitted to the oklahoma animal disease diagnostic laboratory during a 15-year period. rates of seropositivity ranged from 4.7% to 17.6% on samples submitted for anaplasmosis testing of adult cows. the geographic distribution of recorded cases of anaplasmosis was 35 oklahoma counties in 1977 and 48 oklahoma counties in 1991.	1994	8068752
use of a nonradioactive dna probe for detection of anaplasma marginale infection in field cattle: comparison with complement fixation serology and microscopic examination.	a sensitive anaplasma marginale-specific 409-base pair dna probe was developed in a previous study for detection of a. marginale infection in experimentally infected cattle with a test that employed slot-blot and in situ hybridization. to test the suitability of the probe to detect a. marginale in the blood of naturally infected carrier cattle, slot-blot hybridization was used to determine the infection rate of a. marginale in cattle from 3 geographic areas in oklahoma. for comparison, blood sam ...	1997	9087923
establishment and characterization of an oklahoma isolate of anaplasma marginale in cultured ixodes scapularis cells.	anaplasma marginale is a tick-borne hemoparasite of cattle worldwide. the virginia isolate of a. marginale was propagated previously in a cell line derived from embryos of the tick, ixodes scapularis. the cultured anaplasma (va-tc) was passaged continuously for over 4 years and retained its infectivity for cattle and antigenic stability. we report herein the continuous in vitro cultivation of a second isolate of a. marginale derived from a naturally infected cow in oklahoma (ok-tc). blood from t ...	2000	10669100
major surface protein 1a effects tick infection and transmission of anaplasma marginale.	anaplasma marginale, an ehrlichial pathogen of cattle and wild ruminants, is transmitted biologically by ticks. a developmental cycle of a. marginale occurs in a tick that begins in gut cells followed by infection of salivary glands, which are the site of transmission to cattle. geographic isolates of a. marginale vary in their ability to be transmitted by ticks. in these experiments we studied transmission of two recent field isolates of a. marginale, an oklahoma isolate from wetumka, ok, and a ...	2001	11730800
vaccination of cattle with anaplasma marginale derived from tick cell culture and bovine erythrocytes followed by challenge-exposure with infected ticks.	anaplasmosis, a hemolytic disease of cattle caused by the tick-borne pathogen anaplasma marginale (rickettsiales: anaplasmataceae) has been controlled using killed vaccines made with antigen harvested from infected bovine erythrocytes. we recently developed a cell culture system for propagation of a. marginale in a continuous tick cell line. in this study, we performed a cattle trial to compare the bovine response to vaccination with a. marginale harvested from tick cell culture or bovine erythr ...	2002	12243900
anaplasma marginale msp1alpha genotypes evolved under positive selection pressure but are not markers for geographic isolates.	anaplasma marginale (order rickettsiales, family anaplasmataceae), a tick-borne pathogen of cattle, is endemic in tropical and subtropical regions of the world. many geographic isolates of a. marginale occur in the united states and have been identified by major surface protein 1a (msp1a), which varies in sequence and molecular weight due to different numbers of tandem 28- to 29-amino-acid repeats. the present study was undertaken to examine the genetic variations among isolates of a. marginale ...	2003	12682152
flow cytometric evaluation of selected antimicrobial efficacy for clearance of anaplasma marginale in short-term erythrocyte cultures.	the tick-borne rickettsia, anaplasma marginale, causes the economically important cattle disease anaplasmosis. once infected, cattle remain lifelong carriers. herein, we used flow cytometry to test the efficacy of three antimicrobials; oxytetracycline, imidocarb and enrofloxacin against virginia (vgn) or oklahoma (ok) a. marginale isolates in short-term erythrocyte cultures. parasite viability was assessed using the vital dye hydroethidine (he), which is detectable when living organisms convert ...	2006	16669861