MENAGE TO LIVESTOCK

Waikato Times, Volume 127, Issue 21199, 23 August 1940, Page 18 (Supplement)

MENAGE TO LIVESTOCK

Internal Parasites Danger. LOSSES OF LAMBS AND CALVES Farmers Can Undertake Treatment. The problem of internal parasites is becoming an increasingly difficult one in the Waikato. The big increase in the district’s flocks has tended to accentuate this problem and every farmer must be on his guard to protect the health of his lambs and calves from internal parasites. At present, when farmers are organising themselves in a national drive to increase production, even greater precautions must be taken against any increase in livestock mortality. The annual mortality among hoggets from internal parasites is increasing from year to year, states the Livestock Division of the Department of Agriculture in a timely article on the parasite problem. On some properties this loss is assuming enormous proportions. Similarly, losses amongst calves are proportionally high. This article is intended to discuss various important aspects of the problem, and to give the available information both for the treatment of sheep and calves. Where sheep are suffering from internal parasites, both from the symptoms they exhibit and a post-mortem examination, a farmer should attempt to diagnose the cause of the trouble for himself. It is not very difficult on post-mortem to demonstrate at least a few worms, but that this does not mean a great deal is borne out by the fact that practically all our fat lambs going through the works carry a small number of parasites with them. This is less incredible when it is realised that, on the average, a hogget harbours ten or eleven of the possible eighteen varieties with which it could be infected. It is obvious now that two important questions arise : (a) Which parasites are definitely harmful ? (b) How many of the harmful variety must be present to cause the death of the animal ? From our existing knowledge there are three, and sometimes four, varieties which are a source of trouble, excluding fluke in the Hawke’s Bay area. Of the four varieties, two affect hoggets only, and two affect all classes of sheep, especially lambs, lambing ewes, ewes with lambs at foot, and broken-mouthed ewes. Small Intestinal Worm Popularly known as the ’’black-scour” worm, and found in the first 15ft. of the small runners and occasionally in the fourth stomach. It measures from l-Bin. to 4 in., and is found adherent to the walls of the bowel where it can be seen by holding up the opened runner to the sun, stretching it between two hands. It affects only hoggets, and is the chief one responsible for the annual hogget mortality. Furthermore, only one drench has any efficiency against this parasite, and is at the most only partially effective. As regards the number

necessary to cause the death of an animal, ten to twenty thousand must be present. Medium Stomach Worm Found entirely in the fourth stomach, particularly towards the narrow end, which joins the small runners. It measures up to lin. and is usually brownish-red in colour. Although of less importance than the previous parasite, only eight to ten thousand are necessary to cause the death of an animal. Large Stomach Worm Also known as the ‘‘barber’s pole” worm, because of the red and white spiral markings on the female, which measures up to an inch in length, the male being slightly smaller. This is a particularly dangerous parasite, and affects all classes of sheep. Fortunately, however, a wide range of drenches have a high efficiency against it. It is found in the fourth stomach entirely, and any number over one thousand should be considered serious. The Large-mouthed Worm It is becoming of more importance every year, and if the crown is opened by means of a knife or pair of scissors it will be found as a small, stout, white worm, £in. in length, clinging to the wall of the bowel and surrounded by pin-point haemorrhages where it has been clinging previously. So far, no drench effectively removes the parasites. Two or three hundred worms is a heavy infestation. The symptoms shown as a result of heavy infestation with the large stomach worm are very characteristic, due to the fact that this parasite is a notorious blood-sucker. If the wool is parted the skin is found to be lily-white in colour and similarly the inner lining of the eyelids and the gums. Usually there is no diarrhoea, but this is not invariable. On the other hand, hoggets suffering from small intestinal or medium stomach worms have a normal pink lining of the eyelids, and also the gums are quite normal, but the skin may be a little pale. Diarrhoea is very frequently present, but if absent, the droppings are soft and mushy, not necessarily staining the hindquarters. Treatment Small Intestinal and Medium Stomach Worm—As previously mentioned, there is only one mixture which has any efficiency against the two above parasites, and at the most is only about 60 per cent, efficient. This mixture is bluestone and nicotine, made up as follows, in 2 per cent., 4 per cent., or 5 per cent, strengths, depending on the size of the funnel or gun possessed by the farmer : 2 per cent : Dissolve 16oz. bluestone in 5 gallpns of water, and add 1 6 fluid ounces of 40 per cent, commercial nicotine sulphate. 4 per cent : Same quantities of bluestone and nicotine, 2J gallons of water. 5 per cent : Same quantities of bluestone and nicotine, 2 gallons of water.

A Warning. Where lambs are weak, draft them off and give them the next dose lowest down, according to age, and repeat it in ten days; otherwise, with a full dose, they may die. The Large Stomach Worm. A wide range of drenches are highly efficient against this parasite, including the above

bluestone and nicotine mixture, but where a farmer is treating adult sheep the nicotine should be omitted owing to its cost, and the fact that the bluestone alone will be equally efficient. Contrary to what is believed in some districts starvation, even for a short period, is unnecessary, but sheep should be held in yards for a couple of hours after drenching. Where used as a preventive measure, drenching should be carried out at three-weekly intervals, but where animals are actually exhibiting symptoms before drenching is started, it should be repeated in fourteen days, and then at three-weekly intervals. Where losses are experienced annually, start drenching at weaning-time, or, if necessary, before weaning. Hie large stomach worm is a summer parasite, and in suitable seasons lambs may show symptoms before weaning. Prevention Owing to the low efficiency of the bluestone and nicotine mixture against the small intestinal worm, it cannot be considered as the first line of attack in controlling the parasite. So far, adequate nutrition and proper pasture management are the two important fundamentals in combating the effects of this parasite, and until more effective treatment is available they must be considered the first line of defence. On the other hand, where the large stomach worm is concerned the very high efficiency of the treatment available makes this measure the primary one in any scheme of control. It should be borne in mind that every parasite which a sheep harbours must be picked up from the pasture—they do not multiply inside the sheep. Therefore, sheep management will aim at preventing sheep picking up a heavy infestation by avoiding long periods of stocking, especially on paddocks which are heavily stocked, and so heavily contaminated with parasites. Every property presents its own particular problem as far as prevention and control is concerned, but the following general principles should be borne in mind : ( 1 ) Ewes should be treated, at least once, at three weeks before lambing in order to keep the lambs at foot on as clean pastures as possible; (2) Lambs should be weaned on to areas which have been rested or burnt off, and should be rotated as far as possible. This becomes essential where pastures are highly improved and have a heavy carrying capacity. Overstocking is one of the most dangerous factors in hogget mortality; (3) Treatment should be begun at weaning-time or earlier, and not left until the animals are dying. Where trouble has been experienced one year, drenching should be started early the following year, unless an exceptionally dry summer is evident, when special care must be taken to see that sheep do not concentrate entirely on creek banks and river-beds, which become hot-beds of infection and typical danger areas; (4) Hand feeding or winter feeding must be started early, because if sheep become too weak, loss of appetite results, with subsequent mortality; (3) It is important with rotation of sheep and cattle that the latter should be over twelve months, when they do not harbour parasites which may be a dangerous menace to sheep. Treatment of Calves Throughout this article sheep have kept well in the foreground, but the principles of prevention apply equally well to calves. Unfortunately, knowledge about calf parasites is rare, but there is little question that heavy losses do occur from this cause. Where calf paddocks are used the year round without spelling, and where no rotation of calves is practised, heavy losses must inevitably occur in the favourable season. The following drenches can be used with some effect, varying in efficiency with the parasites present: ( 1 ) Bluestone.—Dissolve Boz. bluestone in 3 gallons water. Dosage ; Calves, four months, 30z.; six months, 40z.; nine months, 60z.; twelve months, Boz. (2) Carbon Tetrachloride.—This mixture is frequently used for calves in high dosage, but when a lime-deficiency is evident heavy losses may occur from poisoning. (3) Tetrachlorethylene.—This can be used in doses of from 1 0 c.c. to 30 c.c. in liquid paraffin, but should be followed by a dose of Epsom salts.

Dosage 2 per cent. 4 per cent. 5 per cent Adults— 2 oz. 1 oz. (30 c.c.) 20 C.C. Two-tooths— lioz. Joz. (25 c.c.) 15 c.c. Lambs, 8-12 months 1 oz. ioz. (15 c.c.) 10 c.c. Lambs, 4-8 months %oz. foz. (10 c,c.) 8 c.c. Lambs under 4 months— ioz. ioz. ( 8 c.c.) 5 c.c.