Digest

Pacific

Planters '

Treating Pig Mange

PIG mange is as common in the tropics as in piggeries elsewhere.

It is a disease often confused with parakeratosis, which causes pigs to develop a rough, scaly skin. The best way to distinguish between the two is to remember that pigs with para keratosis do not rub against fences and buildings to relieve the itch the way they do with mange. If possible, a laboratory examination of skin scrapings is the best way to identify the complaint.

Serious loss of condition and slow growth will be encountered if mange is allowed to go unchecked. The dis order is caused by a microscopic mite which lays its eggs under the pig’s skin. On hatching, the mites cause considerable irritation by burrowing through the skin.

BHC spray is the best means of controlling mange. All pigs should be sprayed thoroughly at 10-day in tervals once the disease breaks out in a piggery. Spraying should be con tinued until it disappears.

The strength of the BHC spray is 0.1 to 0.25 per cent, of the gamma isomer of the preparation. Thin or very young pigs should be treated with the weaker spray, but strong pigs can stand the 0.25 per cent, solution.

If pigs are sprayed in their pens, precautions should be taken to pre vent the spray from getting into their troughs. If the troughs are movable, it is best to take them out of the pens.

Cram the pigs into a comer of the pen and wet them thoroughly with the spray, taking special care with the head and face. Sheds and bedding should also be sprayed.

Fiji's Ginger Exports

GINGER can be an export earner.

In Fiji, exports of ginger have climbed to an annual £16,803.

The fastidious American and Canadian markets take most of it.

If planted in October each year, ginger begins to mature from the fol lowing May. To prevent immature, or overmature, ginger leaving the country and so spoiling the reputa tion for standard, Fiji shipments are

normally only permitted between May 1 and December 31. Shipment dates vary according to season and some year’s first shipments have not been until July.

A minimum size of five inches is required for each piece, which must also be fresh, dry and washed abso lutely free of soil or other matter.

Ginger with soil adhering to it is likely to be refused entry in the States.

Ginger is very brittle so care is necessary with packing. Crates of 50 lb and boxes of 25 lb are used, sometimes with paper lining.

Scale is ginger’s biggest pest. Since it is easy to overlook small scale all ginger is fumigated before shipment.

Methyl bromide is the fumigant used, the actual fumigation taking from two to three hours.

Nematodes are becoming more and more apparent in Fiji’s ginger, and so far the chemical fumazone has kept them in control.

Watch For Cattle Blight

CATTLE blight responds quickly to antibiotics in all its stages, and in general the new drugs have sup planted the once-favoured silver nitrate, boric acid and zinc sulphate solutions.

Chloromycetin and temamycin are among the most effective anti biotics and the powder puffer-pack preparations are widely used, as they are so convenient to handle.

Ophthalmic ointments tend to give better results. Treatment of infected cattle is difficult because of the fre quent applications necessary when the increased flow of tears from the eyes washes out any drug used.

Cattle blight is a highly infectious disease, and flies and dust play im portant parts in promoting epidemics.

Irritation of the eye membrane by dust may also predispose to infection.

Previous exposure will confer an immunity from further attacks for up to a year and will play some part in determining the spread of the disease.

The disease affects all breeds of cattle but it has been suggested that the Brahman breeds may be relatively resistant to the disease.

The earliest signs of cattle blight are a copious watery discharge from one or both eyes, the cheek becoming tear-stained and the hair matted. The cattle have a tendency to continu ally blink or to keep the eye partly or completely closed.

A slight temperature may be noticed and also a poor appetite.

There may be a reduced milk supply in dairy cattle.

A few days after infection occurs

an opacity may appear at the centre of the cornea which may become elevated and eventually ulcerate.

Some mild cases clear up within weeks but mostly blight takes a more serious form.

If the disease is severe the opacity is usually white to yellow, and the cornea and conjunctiva will be covered with a granular inflammation and appear very congested. The eye colour tends to become white or pink depending on degree of cloudiness and inflammation. The discharge from the affected eye usually shows the presence of pus in the later stages.

Recovery occurs in three to five weeks and blindness is common in the recovery stage but is usually only temporary. The great majority of animals recover, but a small per centage remain blind.

In severe chronic cases there are more extensive changes due to secondary bacterial infection. There may be bulging of the eyeball with ulceration which may lead to rupture, and permanent blindness will re sult.

In beef herds the disease would appear to take from eight to 10 weeks to run its course through the herd.

In severe outbreaks up to 10 per cent, of young cattle are affected at one time.

The incidence is highest in young cattle, decreasing with age.

Attack The Taro Attackers

IT’S not only Islanders who relish taro or dalo, but leaf eaters, stem cutters and leaf suckers hop in for their share, which too often con stitutes the major portion of the feast. No growers need lose out to the insects, for they are quite easy to control if early action is taken.

Of the leaf eaters, the cluster caterpillar and hawkmoth caterpillar cause large holes in the leaves and can even eat the whole leaf away, leaving only the veins.

The caterpillars vary in size when fully grown, from H inches to four inches, and may be found feeding singly or in groups. The cluster caterpillar prefers the underside of the leaves.

At the first sign of caterpillar damage a 20 per cent DDT emulsifi able concentrate spray should be used, using one ounce in one gallon of water. As an alternative leaves can be dusted with five per cent.

DDT powder. In both cases the underside of the leaf must be treated as well as the top.

Stem cutters are cutworms which,

as likely as not, are difficult to find for they have a habit of lying in the soil or in the lower part of the stems during daylight hours.

Stem cutters work according to their name, cutting the leaf stems at ground level. DDT emulsifiable con centrate is very effective also against the cutters but it is recommended the emulsiable concentrate be sprayed on the surface of the soil around the plant and at the base of the plant itself. Spraying of the leaves will have no effect.

Under the heading of leaf suckers come leafhoppers, aphids, whiteflies and mites, all minute in size—the largest being the leafhopper, which

may measure up to i inch in length.

The suckers cause damage by sucking plant juices, causing small wounds, and wilting and subsequent shrink ing around wounds may lead also to discolouration of the leaves.

Again it is DDT which is the answer.

But with whiteflies and mites it is necessary to use Diazinon 15 per cent, emulsifiable concentrate at one ounce in three gallons of water. If both kinds of pests are present it is necessary to mix the two sprays to gether.

Since most of the leaf suckers are to be found on the undersides of the leaves care should be taken with these.