They work their way or are coughed up to the trachea and finally end up in the intestines where in two to three weeks they develop into mature female worms. The larvae can also be passed from the blood stream into the milk infecting young animals while they nurse. Apparently, the worms are not passed to the fetus in the womb. Adults carry a certain amount of immunity to the intestinal form of these parasites, rarely suffering any effects. Sickness or stress however, can cause the worms to take advantage of the situation and build up in large numbers.
Heavy infections can cause diarrhea, loss of appetite and weight loss.
Continual reinfection results in episodes of coughing as the immature forms migrate to the air passages. If your goat has a large overload, you may see the tiny white worms in the feces. When the larvae penetrate the skin it causes intense itching and the victim may have a brief rise of temperature and a slight headache. As the larvae migrate through the lungs they cause symptoms of lethargy, anorexia, cough and sometimes of mild bronchopneumonia. The clear, colorless oval eggs are small and since embryos have usually begun to form by the time the eggs are passed out with the feces they are easily identified.