What might be a significant consequence of failing to treat a severe infestation of nematodes in goats?

A significant consequence of failing to treat a severe infestation of nematodes in goats is decreased weight gain. Nematodes, or roundworms, can cause a variety of health issues in affected animals, leading to malnutrition and decreased feed efficiency. When goats are infested with these parasites, they often struggle to absorb nutrients effectively, which results in poor growth rates and overall body condition.

Nutritional deficiencies caused by parasitic infestations can also lead to a weakened immune system, making the animals more susceptible to additional health problems. Consequently, the inability to gain weight can have long-term effects on the goats' productivity and reproductive performance.

In contrast, improved milk yield, increased mating success, and enhanced coat condition are not likely outcomes of a severe nematode infestation. These indicators are generally associated with healthy animals; hence, a significant parasitic burden would adversely affect those conditions instead.