Digest

Pacific

Planters'

Treating Parasites

In Horses

TWO main types of internal para sites cause trouble in horses everywhere, but horse owners in warm, humid areas of the Pacific complain that worm eradication is well nigh impossible.

Horses pick up worms and bots in warm and moist conditions and the animals have their greatest prob lem with the parasites when grazed continually over the same ground.

The continual grazing can be avoided by maintaining two horse paddocks and resting one while the other is being used. The rest period should be at least three months, but preferably 12.

Horses should always be drenched before they go into a clean paddock.

Cattle can be grazed in the resting horse paddock, since the worms from one do not affect the other.

The most common worms in horses are pin or whip worms (Osyuris) and strongyles. Strongyles are the most important parasites and the large type are about 1 inch (more or less) in length. They suck large quantities of blood and irritate the bowel; and sometimes they migrate through various organs and blood vessels, causing untold damage and sickness.

Small strongyles are almost as serious as the large strongyles, but they do not migrate and hence con fine their damage to the bowel. They are about i inch to \ inch.

Pin worms come up to 4 inches in length. Their presence may be suspected when the horse continually rubs its tail against posts, rails and trees. Large numbers of pin worms help to aggravate a red worm infes tation.

Round worms in horses are not as common as red worms or strongyles, but they can be a problem in young animals. Stomach worms nestle close to the lining of the stomach and one type forms a big fibrous nest. They are not as serious as the strongyles, but may reduce a horse’s appetite quite seriously.

Bots are large red grubs that cling m clusters to the wall of the stomach

and are the larvae of the hot fly.

Adult flies lay their eggs on the hairs of the horse’s legs and chest, which hatch when licked, and the tiny larvae enter the mouth and tongue. They slowly make their way to the stomach, where they grow and remain for about a year before passing out to pupate and complete their cycle.

Worm control is possible, even in the tropics, although surveillance must be constant to maintain control.

The best possible period for treat ment is winter, with follow-up treat ments in early summer for horses in heavily infested areas.

Tests have shown the most effective chemicals against worms as pheno thiazine, thiabendazole and pipera zine. For bots Neguvon (50 per cent, powder), Nuguvon (62 per cent, liquid) and carbon bisulphide (in flammable liquid) are excellent.

Phenothiazine (green powder) is an efficient and cheap means of worm eradication, and is especially good for stockhorses. It is not suitable for mares heavy in foal or for horses in training. Stockhorses should be rested for four days after treatment.

Phenothiazine is not palatable in feed and should be administered by tube, ball or drenching gun.

Thiabendazole (white powder) is very efficient, very safe, but more ex pensive. It is excellent for mares in foal, valuable animals and youngsters.

It has the added advantage of being palatable in feed and iust as efficient by tube or ball.

Piperazine (white powder) is very safe, fairly expensive and not as efficient against the large strongyles.

However, mixed with phenothiazine or thiabendazole the result is improved.

It is taken fairly well in feed and it is advisable to get a chemist to weigh single doses.

Neguvon (50 per cent.) is not only effective against bots, but it also re moves some worms. It is taken well in feed or given as a ball. If a tube or drenching gun is being used Neguvon (62 per cent, liquid) is pre ferable. Horses must not be drenched within 10 days of dipping or spraying in an organic phosphate preparation.

Carbon bisulphide is effective against bots only and can cause colic in some animals. It should not be given to horses in poor condition or to mares in foal. It should be used only by tube or ‘bot bomb’, and it should be remembered that it is inflammable and hard to carry.

Carbon bisulphide has the added disadvantage of being effective if ad ministered only after the horses have been starved for 24 hours. Starving

is not necessary with any of the other chemicals.

Local agricultural officers will ad vise on dosages and on chemical com binations to treat both worms and bots together. Dosages vary accord ing to the animal’s size, age, con dition and value.

Keep An Eye On

Stored Grain

STORED grain becomes much more susceptible to insect attack when stored under moist conditions. Moist conditions are difficult to avoid in some areas during certain periods of the year.

If bulk storage is not available, and it is necessary to store grain in bags, there is a greater danger of infestation by insects. If the bags are to be stored in barns, the barns should have a boarded or concrete floor, and be as weathertight as possible. The bags should be stacked on pallets, one foot away from the walls. New grain should not be stacked near older grain.

Grain subjected to too much moisture may heat, resulting in moulding and rotting. It is usually accepted as unsafe to store grain that has above 12 per cent, moisture. An exception to this is shelled maize, which can be safely stored at moisture levels up to 14 per cent. Grain in this condition is known as “prime dry”.

Grain can be protected from insect attack with dusts which are mixed with the grain before bagging or stor ing in bulk. Some insecticidal dusts will give varying periods of protec tion, and will not affect the germina tion of sound, dry grain if the recom mended rates are followed.

Stored grain should be inspected often, and during the warmer periods of the year inspection should take place every month.

Look first for living insects in the grain; a suitable sieve can help such examinations. Insects, however, are often active in grain without there being outward signs of heavy infesta tion. The most satisfactory way to check this is to determine the tem perature inside the grain mass. Insert a thermometer in the grain attached to a suitable probe, or lower it down a hollow tube inserted in the grain.

No absolute critical level can be given: But temperatures above 70 deg. Fahr. favour development of in sect pests, and temperatures above 80 deg. Fahr. in sound dry grain almost certainly indicate insect activity.

Fumigation is the only really satis factory way to control an infestation of insects in stored grain. Several different fumigants are available and

it should be remembered fumigants will not affect germination of sound dry grain if the recommended rates and exposures are followed. How ever, do not fumigate grain with an excessive moisture content if it is wanted for seed purpose.

It should also be borne in mind that all fumigants are toxic to man as well as to insects and precautions should be observed.

Improvement Hopes

For The Coconut

WORK of importance to all South Pacific coconut planters is now proceeding at the Pacific Islands Farm Institute, at Metalanim, in the Ponape district of the US Trust Territory of Micronesia. There, the South Pacific Commission’s tropical agriculturist, Mr. K. Newton, has organised research aimed at improv ing the coconut.

No overnight results are expected from the experiments, which are in fact variety trials. The coconut is notorious for its wide variation, en compassing the entire range of Pacific environments, from rich volcanic soil to nutrient-deficient coral atolls.

At Metalanim, some 12 acres have been prepared to receive the flow of seed coconuts Mr. Newton has ar ranged from all over the Pacific.

Eight varieties have been selected from the Trust Territory itself, and from Fiji, the Solomons, the New Hebrides, Papua-New Guinea and French Polynesia. The selection, treatment, packing and airfreighting are being financed by the SPC, and the first shipments reached Metalanim in July.

One hundred seednuts of each variety will be flown into the Farm Institute to be germinated by tech niques developed as a result of recent experimentation with favourable en vironments for high germination rates. It is anticipated that about 60 seedling palms of each variety will be planted out late in 1966, to a systematised layout designed with assistance from the CSIRO Division of Mathematical Statistics, Canberra.

When the palms come to maturity, the nut size, copra yield and quality, disease resistance, etc,, can be com pared among the eight varieties repre sented in the Metalanim trial, and with the results of similar trials estab lished in recent years in Jamaica, the Solomons and New Guinea.

On the basis of these results, large seed gardens can then be established to provide high grade seedlings for re-planting schemes in existing plan tations and for the establishment of new ones.