A620
Parasite Control and Prevention

 1. Ostertagia (brown stomach worm)
 2. Haemonchus (barber pole worm)
 3. Trichostrongylus (small stomach worm)
 4. Cooperia (small intestine worm)
 5. Nematodirus (thread-neck worm)
 6. Bunostomum (hookworm)
 7. Strongyloides (threadworm)
 8. Oesophagostomum (nodular worm)
 9. Coccidia (Eimeria)
10. Cryptosporidium
11. Fasciola hepatica (liver fluke)
12. Dictyocaulus (lung worm)
13. Hypoderma (cattle grub internally)

14. Lice
15. Cattle Grubs (Hypoderma)
16. Mites
17. Face and Horn Flies
18. Ticks

Clinical Signs: Signs of parasite infestation are most common in young, very old, or diseased animals. Each infected animal, depending on the parasite or parasites it is infected with, will have different signs of disease. In general, most infections cause weight loss, unthriftiness, and poor weight gains. Some parasites can cause diarrhea, decreased appetite, poor conception rates, and fluid retention (bottle jaw).

Disease Transmission: Each internal parasite is spread by orally ingesting the infective stage of the parasite. This most commonly occurs during grazing. External parasites are spread by direct contact or having infested animals in close association with other animals.

1. Internal Parasites - Most of these infections can be detected using a fecal egg count. This is done by collecting a fecal sample and sending it to a local veterinarian for fecal flotation. See page D220 for more specifics. Often these infections can also be diagnosed at necropsy.
2. External Parasites - Parasites or the signs associated with infestations can be observed upon routine examination of the animal.

Treatment/Prevention: Different treatments are based on the common parasites encountered and geographical location. Remember that the time to treat cattle grubs depends on the area where the cattle reside or where the animals come from. Consult the package insert or a local veterinarian for more information.

* These numbers correspond with the numbers found above.
**The meat withholding numbers depend on specific product. Refer to the exact
product for meat withholding.

1. Products for internal parasite control (some of the major ones):

2. Products for external parasite control:

Organophosphate Ear Tags:

Pyrethroid and Combination Ear Tags:

Notice that each ear tag contains very different amounts of insecticide. When selecting an ear tag, consider not only the cost, but also the amount of insecticide it contains.

Many ear tags will minimize horn and face fly problems.