Lice in Household Poultry

New Zealand Journal of Agriculture, Volume 82, Issue 3, 15 March 1951, Page 267

Lice in Household Poultry

IT7EW household poultry keepers are not aware that fowls are likely to be infested by body lice, but the one who takes measures against lice is a rarity. If control methods were difficult, this inaction could perhaps be understood, but they are not. In this month’s article for the household poultry keeper W. L. Mclver, Poultry Instructor, Department of Agriculture, Hamilton, advises on two of the easiest methods to control lice. There are many other ways of reducing infestation, but the simplest treatments are recommended in the hope of encouraging more householders to put the knowledge to use.

BODY lice are not the only type of louse which infests poultry, but they are the most common. They do not suck blood but are biters, living on skin fragments and debris. Every amateur poultry keeper should make himself familiar with the appearance of body lice and learn how to find them quickly.

They are about the size of a large pin head when fully grown, light straw coloured, and very active. They like warmth and can live only a few days away from the host. So. eager are they for warmth that they cling tightly to the fowl, never leaving it voluntarily. As they prefer the warmest portion of the fowl, ascertaining whether they are present in the flock is simple. If none is found on the abdomen among the fluffy feathers below the vent, almost certainly there will be none on other parts of the body. x They should be sought by parting the loose, fluffy feathers with the fingers and at the same time searching diligently for them on the skin surface disclosed, because they quickly scuttle to cover. Only when the bird is badly infested will they be found on back, neck, and breast.

If they have been on the host long enough to mature and breed, clusters of their eggs are an obvious sign. These will be seen even before the lice, but in such a case the lice will be found readily because the presence of the nits shows a heavy infestation. The favourite place for depositing the nits is at the bases of the feather stems, and especially those of the fluffy feathers immediately below the vent. The nits are grey-white, - pear shaped, laid close together, and firmly attached to the feather shaft. Other types of lice are wing and head lice, each named after the portion of the body' it prefers to inhabit. Wing or shaft lice may be found between the barbs of the large wing feathers, technically called flights and secondaries. Head lice may be found either on the skin or on the feathers of the neck just behind the head. Both wing and head lice are very different in appearance from the "body louse, being much longer, narrower, and dark. The easy way to find out whether wing lice are present is to fan out the wing and hold it against a light or sunshine, making the lice readily visible between the feather barbs. At first sight they may appear to be specks of dust or dirt, an impression which would seem to be confirmed by lack of movement, for even when disturbed they are loath to move. On not more than one bird in a hundred infested with body lice will head and wing lice also be present. In a well-managed flock lice present very little difficulty. Healthy, vigorous, heavily laying fowls seldom have more than two or three lice unless infestation becomes bad among poorer flock mates. Weak, sickly birds so frequently are seriously infested that the lice are sometimes blamed for their weakness. Though the irritation caused by the lice results in loss of condition _ and helps depreciate egg yield, it is the lack of stamina and vigour in the fowl that permits the increase in infestation. Correspondingly, the absence of lice on active birds is often attributed to fowls freeing themselves from the pest by dust bathing. Lice so dislike leaving the source of heat and are so difficult to dislodge that a more likely explanation for their being more prevalent on weak fowls is that active birds clean themselves better and so have insufficient skin debris to feed many lice.

Methods of Treatment The two easiest methods of controlling infestation depend on fumes from nicotine sulphate (40 per cent, strength) killing the lice.

If infestation is not heavy, and particularly if no nits are present, the nicotine sulphate can be simply poured on the perches. The first step is to clean the perches thoroughly of organic .matter. Then with a cloth smear a layer, of luke-warm, soapy water along the perch tops; the water prevents the nicotine sulphate from sinking into the timber and the soap suds stop the nicotine from dissolving too rapidly. Some manufacturers of nicotine sulphate supply with the bottle a spare lid with a small hole in it, and they call this the applicator cap. The hole permits one drop at a time to come out when the bottle is shaken, unless it is done too vigorously when more than one drop may come out. Shake drops of nicotine sulphate on the perches at intervals of about l-gin., using 1 fl. oz. to 20ft. This treatment should be carried out a few minutes before perching time, or even after some of the fowls have begun perching for the night, and be repeated 10 days later. This method can be used as a. preventive •to stop heavy infestation by applying it every 3 months.

If infestation is heavy, a more effective remedy is to apply the nicotine sulphate directly to the skin of each fowl. The perch method does not kill head or wing lice. Only 9 drops are required for each bird, but none must be allowed to fall into the opening of the vent. The feathers are parted so that the drops fall on to the skin of the abdomen, wings, breast, and back of the neck. The method is illustrated on the opposite page. The treatment must be repeated twice at intervals of 10 days. Sometimes . nit clusters still show even after three treatments, but these are either infertile eggs or material for fastening the nits to the feathers.