SCOURING AND MORTALITY

Press, Volume LXX, Issue 21324, 17 November 1934, Page 22

SCOURING AND MORTALITY

HEAVY TOLL OF EWES METHOD OF PREVENTION Because of the abundance of luscious spring growth this season there has been a heavy incidence of scouring among sheep and accompanying mortality among ewes. This complaint in ewes is not unusual at this season of the year, but the extent and severity of the occurrences this year has been more pronounced, and the death rate has reached a high level in many districts, especially in those where frequent showers have been experienced. The trouble has been extensively and thoroughly investigated by the Veterinary Department of Canterbury Agricultural College, Lincoln, and its head, Mr A. Leslie, described his experience and findings in an interview with a representative of "The Press" this week. The abundance of apparently suitable feed in the districts affected is one of the most disconcerting features to farmers, he explained. However, because of the plentiful supply of green growth in Canterbury outbreaks can be associated with a more or less sudden change from winter feeding to an abundance of stimulating laxative green growth. A common observation has been the excellent growth and condition in the offspring of affected ewes. In most outbreaks the incidence has been highest and most severe in ewes rearing twins. Two-tooths and old ewes are frequently affected. It is very noticeable that in most affected flocks the main article of diet up to lambing was roots, and most —but not all—were lambed on to unripe but good second growth of rape. In some places this diet was fed for nearly a month. Other flocks were lambed on to green feed oats. History of Affected Flocks The onset of scouring varies considerably and depends on precipitating factors. Observations in some places show that the affected ewes show most symptoms from two or four weeks after lambing, while in other cases the most susceptible period was from four to eight weeks after lambing. Deaths occurred approximately a fortnight after marked scouring began. There have been many instances this season of 40, 50, and 70 or more ewes dying in flocks of from 500 to 900 ewes A striking feature in affected flocks has been the good milk production of ewes after lambing and stimulation by the luscious feed. The abundance

of growth stimulated the milk production and in consequence lambs have done well until scouring upsets the health of the ewe. As soon as the milk yield declined lambs become unthrifty and themselves have started to scour. Many in badly affected flocks have automatically weaned themselves. There is no evidence to show that scouring in lambs or ewes is caused by parasitic worms, although it is true that scouring lambs may be i more susceptible to worms on account of their slower growth and poorer condition. Help From Experiments The result of practical eperiments a I Ashley Dene, the experimental farm of the college, throw important light on the troubles. Data gathered there from 80 special cases taken of sheep in various degrees of scouring disprove that the watery nature of diet is the sole cause and also rules out worm parasites as a cause. Records of body weight of affected ewes during and subsequent to pregnancy show clearly that ths abundance of feed is a precipitant and the scouring is only a symptom of malnutrition brought on by production in animals with depleted resources. The college records show that the worst cases of scouring have occurred in twin rearing ewes that were inadequately fed during the winter. The good growth made by offspring of affected ewes up to the decline in milk production singles out milk production as a precipitating factor also. The size of the ewe is also a factor. Small ewes bearing twins are frequently affected. How To Avoid Trouble The practical results and their possible application so as to avoid trouble are most important. It would appear that a sudden change from winter feeding to a diet which is stimulating and suitable for well-nourished stock only is most significant in predisposition High milk production stimulated by good feed adds to the depletion of body reserves and often causes deaths in ewes that could remain healthy only by a gradual improvement m the quality and quantity of I the diet. The essence of prevention in seasons with an abnormal abundance of spring growth, and where better winter feeding is impracticable or uneconomic, is to depend on regulating the amount of spring growth allowed and where possible supplementing that controlled feeding with oatsheaf chaff hay and minerals for two or three weeks. This method allows depleted and high producing ewes time fc- adjust themselves. 1934 SHOW SEASON ROSTER OF DATES South Island Agricultural and pastoral shows have been arranged as under. Secretaries are invited to notify dates of their shows for inclusion in the list: November 17—Courtenay. November 20—Banks Peninsula, at Little River. November 20 and 21—Otago Metropolitan. November 22 and 23—Clutha. December 4 and s—Gore. December ■ 7—Wyndham. December 11, 12 and 13—Royal Society's Show at Invercargill. North Island November 21 and 22—Stratford. 1935 February 22 and 23—West Coast, at Greymouth. March 16—Mayfield. March 21 and 22—Christchurch (ram fair). •£? arc £ 26—Amuri, at Waiau. L Marafc \