Trombiculid mites (chiggers) also feed on blood, but only in the larval stage. The life-cycle starts with eggs laid in the environment of the normal hosts of the larvae, typically rodents and other small mammals. After the engorged larva molts to a nymph the remaining life-cycle comprises stages that are not parasitic, but free-living. There are several nymphal stages. The adults can be found crawling on vegetation, conspicuous with a dense covering of red setae (similar to hairs). "Trombicula autumnalis", the harvest mite, causes severe pruritus to its host after it has detached. Feeding by the larvae involves secretion of a feeding tube, the stylostome, into the host's skin. This remains when the larva detaches and proteins in the secretion induce inflammatory and dermal hypersensitivity reactions, with intense pruritus. Domestic birds, dogs and humans are among the other hosts afflicted by this temporary infestation. Some genera of mites have adapted to infesting the lungs and air-sacs of birds or the lungs of mammals. "Cytodites nudus" is a typical species of this type. It infests poultry in North America and South Africa and may cause reduction in productivity of the birds. Another genus of similar bird infesting mites is "Laminosioptes". The genus "Pneumocoptes" has species that infest the lungs of some monkey and rodent species. These mites aggregate in nodules within the lung but signs of clinical disease are not obvious. "Pneumonyssus caninum" infests the nasal sinuses of dogs. These can be caused indirectly by free living mites within the fabric of building and on stored foods such as grain and hay. They are most commonly seen as asthma and dermatitis in humans living in the housing or handling the materials but domestic animals such as dogs and horses can also develop similar diseases. The allergic reactions develop in response to foreign proteins within the fecal pellets of the mites. "Dermatophagoides pteronyssinus", the house-dust mite is the best known species causing such problems. Mites causing similar problems are in the genera "Acarus", "Glycyphagus", "Tyrophagus", and others. A variety of mites cause mild dermatitis in their hosts and biting nuisance and disgust to the owners of domestic animals. "Cheyletiella blakei", the cat fur mite is typical.