A Survey of Cattle Ectoparasites and a Study of Psoroptic Mange in Southeast Georgia

A comparison of traditional scrapings vs. a vacuum cleaner method of collecting cattle ectoparasites determined the vacuum method to be as efficient as the scraping method for collecting Psoroptes ovis, and possibly as effective for collecting Bovicola bovis. In a survey of cattle ectoparasites in southeast Georgia, using the vacuum method, B. bovis were collected from cattle in a sales barn with an average of 15% parasitism from January 21 to March 18, 1985. Private herds sampled by the vacuum method, showed no ectoparasites. Cattle grubs (Hypoderma lineatum) were found on cattle in a sales barn from January to early March, 1985, while 4 private herds were virtually grub-free. One private herd of 16 calves was examined regularly for grubs from November, 1984 through March, 1985 with a peak of 73% parasitized and an average of 14 grubs per parasitized animal. The cattle grub season for southeast Georgia seems to begin by November and end around mid-March. Sixteen Hereford heifers, divided into 2 groups (5 stanchioned and 11 unstanchioned) were infested 3 times with P. ovis over 5 weeks, December, 1984 through January 2, 1985. All unstanchioned claves showed no clinical signs of P. ovis5 weeks after the last innoculation with mites. All 5 stanchioned calves developed psoroptic mange. Considerable variation in the progression of the disease was noted. When stanchioned calves with psoroptic mange were released and allowed to self groom, lesions were rapidly removed, indicating self grooming is a natural host control of P. ovis

Fire Ant Decapitating Fly Cooperative Release Programs (1994–2008): Two Pseudacteon Species, P. tricuspis and P. curvatus, Rapidly Expand Across Imported Fire Ant Populations in the Southeastern United States

Natural enemies of the imported fire ants, Solenopsis invicta Buren S. richteri Forel (Hymenoptera: Formicidae), and their hybrid, include a suite of more than 20 fire ant decapitating phorid flies from South America in the genus Pseudacteon. Over the past 12 years, many researchers and associates have cooperated in introducing several species as classical or self-sustaining biological control agents in the United States. As a result, two species of flies, Pseudacteon tricuspis Borgmeier and P. curvatus Borgmeier (Diptera: Phoridae), are well established across large areas of the southeastern United States. Whereas many researchers have published local and state information about the establishment and spread of these flies, here distribution data from both published and unpublished sources has been compiled for the entire United States with the goal of presenting confirmed and probable distributions as of the fall of 2008. Documented rates of expansion were also used to predict the distribution of these flies three years later in the fall of 2011. In the fall of 2008, eleven years after the first successful release, we estimate that P. tricuspis covered about 50% of the fire ant quarantined area and that it will occur in almost 65% of the quarantine area by 2011. Complete coverage of the fire ant quarantined area will be delayed or limited by this species' slow rate of spread and frequent failure to establish in more northerly portions of the fire ant range and also, perhaps, by its preference for red imported fire ants (S. invicta). Eight years after the first successful release of P. curvatus, two biotypes of this species (one biotype occurring predominantly in the black and hybrid imported fire ants and the other occurring in red imported fire ants) covered almost 60% of the fire ant quarantined area. We estimate these two biotypes will cover almost 90% of the quarantine area by 2011 and 100% by 2012 or 2013. Strategic selection of several distributional gaps for future releases will accelerate complete coverage of quarantine areas. However, some gaps may be best used for the release of additional species of decapitating flies because establishment rates may be higher in areas without competing species