The Famacha system, developed by veterinarians in South Africa, is used to gauge the load of Haemonchus contortus (Barber pole worm) being carried in a flock of sheep or goats. The idea is to only deworm animals that actually have an impacting volume of the worm, thus preventing the inevitable resistance to deworming medications that the parasites develop over time. Actually testing each animal's feces for egg volume is impractical on a regular basis so Famacha gives an alternative, only requiring visual observation of the animal's mucous membrane.

The Haemonchus worm is responsible for huge production losses in sheep and goat flocks throughout the world in temperate through tropical regions. It is the number one culprit of parasitic death. Inside an infected animal the worm lays up to 10,000 eggs per day that are shed in the host animal's droppings. In four to six days these eggs develop into larvae if the temperature is 75-85 degrees. The larvae climb the grass if it is wet, to be ingested by another animal. If the temperature is too hot or the climate too dry, the larvae will not survive.

Once ingested Haemonchus larvae pass through the first three stomachs and attach to the lining of the abomasum, where they begin to feed on the host's blood. Within two weeks the larvae reach adult stage and begin shedding eggs, completing the cycle. The Barber pole name comes from the adult female who is red and white striped.

The effect of this parasite on the sheep or goat hosting animal is anemia, from the loss of blood, and edema causing the "bottle jaw" effect (a pouch of fluid that forms just under and behind the lower jaw). Any animal displaying bottle jaw should be dewormed immediately.

The Famacha system uses a laminated full-color card that shows the different colors for the mucous membrane of a sheep or goat's eye, ranging from a healthy red, to lighter shades of pink, finally to white. There are five categories with red identified as (1) and white as (5). Normal is (1) red and shows there is a good ratio of red blood cells to plasma circulating in the animal's bloodstream. White (5) shows there is an anemic imbalance indicating a huge parasite load. As the Haemonchus worm removes the red blood cells while feeding, the plasma begins to leak into surrounding tissues causing edema and the previously noted bottle jaw.

The Famacha card is held up next to the animal's eye. The lower lid is gently pulled down and the color of the membrane matched to the color on the card. A (1) and a (2) indicate healthy animals that do not need to be dewormed. A (3) should be noted, but if fewer than 10% of the flock shows a worse reading then no action is needed. If greater than 10% of the flock is a (4) or (5) then (3)s should be treated, too. All (4)s and (5)s should be dewormed.

The entire flock should be checked every two to three weeks through the summer and possibly more often when conditions are just right for the development of the worm (warm and wet). Also, if an animal is noted lagging behind the herd or is lethargic, it should be checked right away. An animal that shows repeatedly bad scores on this chart should probably be culled from the flock since it has poor natural immunity to the parasite.

The Famacha system allows only those animals that need worming medication to receive it. Overusing dewormers causes a build up of resistance in the Haemonchus population, eventually leading to an area that is unable to support sheep or goat farming. Famacha prevents this by only treating animals that require it.

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