BIOVET AWARDS 1999

Resume

Traditionally, the method of controlling vampire population in Latin America was to capture and topical treatment with an anticoagulant paste on the back of heamatophagous bats (vampires) and its subsequent release.

Currently the Program Control, discovered “The Technique of defanging” which is the cutting of the upper incisors to prevent them from attacking their victims, then treated with anticoagulant and released.

A decrease in the incidence of cattle and humans bite of 98.98%  was observed,  immediately after capture.

Introduction:

Since the discovery of America have been cited cases of rabies transmitted by bats. There is evidence of human cases and in the early colonizing expeditions, as in 1514 in Panama and attacks on animals in Mexico in 1527, as well as other episodes in several Latin American countries from the colony.

In 1975 the first case of human rabies transmitted by bats in Juruti, Pará, Brazil, where the disease caused six deaths were reported, but the growing number of cases, 18 in 1996 in several Latin American countries makes it a big public health problem .

Economic losses from the attack of Desmodus rotundus (common vampire bat) is $ 30 million per year in livestock from countries of tropical America.

In these losses are considered outbreaks of rabies and other diseases that transmit chronic blood loss that causes weakness and acute anemia, wounds are vulnerable to bacterial infections and the action of Liperosis irritans flies and Cochliomy hominivorax are consequent depreciation of skins and low milk and meat production

At present countries with Vampire Control Programs do it by:

1. Capture corrals and refuges using topical anticoagulant in heamatophagous bats captured with subsequent release to exterminate the colonies.
2. 2. Treatment of cattle bitten using the ointment killing vampire on recent injuries for three consecutive evenings.

Materials and methods:

This study was conducted in 30 farms in Costa Rica in the Regions of the Pacific Coast, 30 catches were made in pen using defanging technique with counting recent bites before and after each of them.

To control the population of heamatophagous bats (vampires) in Costa Rica and Latin America have used the networking method is to enclose the cattle bitten on previous nights in a small pen, 4 or more Japanese invisible nets are placed around it, when it has completely obscured the vampire comes fed of cattle and does not detect net, so is easily caught, are placed in a cage when there is a sufficient amount depending on the number of fresh bites the nets are removed, the cattle is freed and proceed to the treatment of each of the vampires caught with a sufficient amount of anticoagulant paste of warfarin [3 – (alpha-acetonylbenzyl)-4-hydroxycoumarin] slow acting than their cleaning habits can contaminate the rest of the colony; immediately after proceed to cut the upper teeth with nail clippers which will not allow the vampire to feed on their victims from the night of treatment.

Results

Vampire nocturnal 30 catches were made using the technique of defanging on 30 farms in the Chorotegan Region Central Pacific, Brunca. The first evaluation was made the same day of the catch, on these 30 captures 780 cattle were housed, with an average of 26 cattle in each of them, they had an attack rate of 98% fresh bites, 764 cattle in the corral had vampire bite wound.

In these 30 catches were defanged, treated and released 813 vampires (with an average of 27.1 vampires / catch).

The second evaluation was conducted the day after each captures in which a decrease of 98.98% bites was obtained, the attack rate in the 780 cattle examined was 8 fresh wounds corresponding to 1.02% .

The third evaluation was performed 12 days after the capture, 780 cattle were examined which showed an attack rate of 10 bites (1.41%), achieving a reduction of 98.59% compared to the first evaluation.

Table nº 1

Conclusions and recommendations

Using this new technique to control hematophagous bat population is achieved reduce the number of bites immediately after making the catch, while the traditional method maintains a high percentage of injuries for the next three nights to treatment .

This selective control method used by the National program is not damaged any of the beneficial species of bats in Costa Rica, instead of being taught how and why to protect livestock, as these mammals are among the most body important in controlling harmful insects nature to Public Health and agriculture, dispersing seeds and pollinating flowers, regenerating and maintaining the diversity of our forests.