What Are Ticks and How to Use Medication to Exterminate Tick Larvae on Dogs and Cattle at Home

In recent years, news of people being bitten by ticks has become commonplace, so what exactly are ticks? How do you kill off tick larvae on your home, dogs, and cattle completely? What medication can eliminate them? The tick (pí) is also called the wall louse, or bie chi, commonly known as dog bie, grass bie zi, cattle louse, grass tick, dog bean, and cattle bie zi. In the Sichuan dialect it is also called bi sha (pronounced shà). It lies dormant in the grass and plants of low hills, or lodges in the fur of livestock and other animals. When it has not sucked blood, the small ones are only as big as a shriveled mung bean, and some are as fine as a grain of rice; after sucking its fill of blood, it becomes as plump as a soybean, and the large ones can reach the size of a fingernail. The anaplasmosis transmitted by tick bites is an infectious disease, and humans are generally susceptible to it. Medical staff or their attendants who have close contact with critically ill patients or direct contact with patients' blood and other body fluids may also become infected if they do not take protective precautions.

I. Classification of Ticks

1. By morphological characteristics

1) Hard ticks

The body is oval; when it has not sucked blood, the abdomen and back are flat, with the back slightly raised, and the adult body length is 2-10mm; after engorging with blood it swells to the size of a red bean or a castor bean seed, and the large ones can reach 30mm in length.

2) Soft ticks

The capitulum is on the ventral side of the body and cannot be seen from the dorsal side, and there is no porose area on the dorsal surface of the basis capituli. The dorsal surface of the body has no scutum, and the body surface is mostly covered with granular small warts, or has wrinkles and disc-shaped depressions.

2. Main species

1) Ixodes persulcatus (taiga tick) has a brown scutum, slender cylindrical palps, and blunt tooth-shaped auriculae on the basis capituli.

2) Dermacentor nuttalli (Nuttall's meadow tick) has enamel-like markings on the scutum, with eyes and festoons; the palps are wide and short, the basis capituli is rectangular, and the dorsal spur of tarsus I is short and bluntly rounded.

3) Hyalomma asiaticum kozlovi has a reddish-brown scutum, with eyes and festoons; the palps are long and cylindrical, with the second segment markedly elongated; the legs are pale yellow with distinct pale rings at each joint; the male has prominent deep cervical grooves and a tobacco-pipe-shaped spiracular plate.

4) Ornithodoros papillipes has a granular body surface, and the intersection of the postanal transverse groove and the postanal median groove is almost at a right angle.

II. How to prevent tick bites?

1. To eliminate ticks on the body surface of livestock and in livestock sheds, insecticides such as trichlorfon and dichlorvos can be sprayed. Housing should be ventilated and dry, wall cracks should be filled and smoothed, caves should be sealed, and livestock barns and poultry houses should be cleaned thoroughly or sprayed with medication to eliminate tick breeding sites.

2. Strengthen personal protection. When entering forest areas or working in the field, wear long-sleeved clothing, tighten the belt, cuffs, and trouser legs, tie a towel around the neck, and apply ointment to the skin surface to prevent tick bites. Take a bath and change clothes after returning from outings to prevent bringing ticks home.

In addition, it is now summer, which is a good season for people to travel. Here I want to remind everyone that when out playing in the field, in addition to paying attention to the above two points, do not go to scenic areas that have not yet been well developed, and try to avoid dense grassy forest and wild areas as much as possible. In this way we can avoid tick bites.

III. What medication is used to kill ticks?

After a certain pesticide is used for a long time, it will cause ticks to develop resistance, so pesticides should be used in mixture or alternately.

There are mainly two ways to eliminate ticks on livestock: one is to catch them directly, and the other is to use chemical drugs to kill ticks. When ticks are found, they should be pulled off and then killed together. When pulling, the tick body should be kept perpendicular to the skin, and then pulled upward, to avoid the tick's false head breaking off in the skin and causing inflammation. However, this method can only be used under the premise of few livestock and sufficient manpower.

As for using chemical drugs to kill ticks, commonly used ones include pyrethroid insecticides, organophosphorus insecticides, amidine insecticides, and so on. According to the season and the target of application, methods such as spraying and dipping can be selected. However, it should be noted that after these pesticides are used for a long time, they will cause ticks to develop resistance, so pesticides should be used in mixture or alternately.

In recent years, genetic control and biological control have begun to be adopted to kill ticks. The former uses radiation or chemical sterilants to make male ticks lose their reproductive capacity, causing the tick population's capacity to continuously decline; the latter uses the natural enemies of ticks to kill them. It has now been found that some parasitic wasps of the family Encyrtidae in the order Hymenoptera can lay eggs in the bodies of some nymphal ticks, and the adults only emerge from the nymphal tick's body afterward; the nymphal tick dies shortly after being parasitized. There are also insects of the family Reduviidae that can also cause ticks to die.