THE AGRICULTUEAL NEWS. 



The Life History 



OF 



The Cattle Tick 



Th© fmpo /tance of accurate tnowledge on this subject lies in the fact that, before methods of eradication can be carried out Intelligently and success- 

 fully, it is necessary to kiidw the life history of the tick, and the intluence ot tenijierature, moisture, and other climatic conditions on the various stages of 

 its existence. In the lolluwiag notes, whenever the term "tick" vr "cattle lirk' is used it refers to the one species, Margaropus anwuXatus, the oommon 

 Cattle Tick, which is so prevalent throughout the West Indies. 



Only 'A part of the development of the tick takes place on the animal host : the rest of the development occurs on the pasture occupied by the host. 



DEVELOPMENT on the GROUND 



X'HE ENGORGED FEMALE. In tracing the life 

 histor>' of the cjittle tick it will be convenient to begin 

 wit*o the large, plump, olive-green female tick, about half 

 an inch m length, attached to the skin of the host. 

 During tlie lust few days ^ent on the host, she has 

 increased enormously in size, as a consequence of 

 drawing a large supply of blood. 



When fully engorged she drops to the ground, and 

 .it once, especially if the weather is warm, begins to 

 search for a hiding place on moist earth beneath leaves; 

 or any other litter which may serve as a protection 

 Irom the sun and numerous enemies, or shield her from 

 unfavourable conditions. The female tick may be 

 devoured by birds, or destroyed by iints. or may perish 

 as a result ot" unfavourable conditions, such ns low 

 temporaTnre. absence or excess of moisture, and m.iny 

 other conditions ; so that many female ticks which fall to 

 the ground are destroyed t>efore they lay eggs. 



EGG LAYING. Egg laying begins during the 

 spring, summer and fall months in from 2 to 20 days. 

 ;md during the winter months in from 13 to 98 (lays. 

 ;ifter falling to the ground. The eggs are small. elliptical- 

 shaped l)odies. at first of a light amber colour. later 

 changing to a dark brown, and are about one-flftieth uf 

 an inch in length. As the eggs are laid they are coatcil 

 with a sticky secretion which causes them to adhere in 

 clusters and no doubt serves the purpose of keeping 

 them from drying out. During egg laying, the mother 

 tick gradually shrinks in size and finally is reduced to 

 about one-third or one-fourth her original size. Egg 

 laying is greatly intluenced by temperature, being 

 retarded or even arrested by cold. It is completed in 

 from 4 days in the summer to 151 days, beginning in 

 the fall. During this time the tick may deposit from 

 a few hundred to more than 5.(K)0 eggs. After egg laying 

 is completed the mother tick has fulfilled her purpose 

 and dies in the course of a few days. 



"SEED" TICKS. After a time, ranging from 19 

 <lay8 in the summer to 188 days during the fall and 

 winter, the Qgi^ begin to hatch. From each egg issues 

 a small oval, six-legged larva or "seed" tick, at first 

 amber coloured, later clianging to a rich brown. The 

 "seed" tick, after crawling slowly over and about the 

 sheU from which it has emerged, usually remains more 

 or less quiescent for several days, after which it shows 

 great activity, especially if the weather is warm, and 

 ascends the nearest vegetation, such as grass, other 

 herbs, and even shrubs. 



COS 



Since each female lays an enormous mass of eggfl 

 at one spot^ thousands of larvae will appear in the 

 course jf time at the same place, and will ascend the 

 near-by vegetation and collect on the leaves and other 

 parts of plants. This instinct of the seed ticks to climb 

 upward is a very important adaptation of Natures to 

 increase their chances of reaching their host. If the 

 vegetation upon which they rest is disttirbed, they 

 become very active and extend their long front legs 

 upward in a divergent position, waving them violently 

 in an attempt to seize hold of a host. 



The seed tick during its life on the pasture takes 

 no food, and consequently does not increase in size, and 

 unless it reaches a host to take up the parasitic po;-tion 

 of its development, it dies of starvation. The endurance 

 of seed ticks is very great, however, as iUey have l)een 

 found to live nearly eight months, even daring The 

 colder jiart of the year. 



DEVELOPMENT ON CATTLE 



"SEED" TICKS, The parasitic phase of develop- 

 ment Ivyins when the larvne or seed ticks reach .a 

 favournl.Ie hor.t, such as a cow. They cr.awl up over 

 the hair of the host, and commonly attach themselves 

 to the ^kin of the escutcheon, the inside of the thighs 

 and flanks, and to the dewlap. They at once begin to 

 draw blood, and soon increase in size, 



THE NYMPH, In a few days the young tick 

 changes from a brown colour to white,- and in from 5 to 

 12 days sheds its skin. The new form has eight legs 

 instead of six and is known as a nymph. 



SEXUALLY MATURE TICKS. In from 5 to 11 

 days after the first mnnlt the tick again sheds its skin and 

 becomes sexually mature. It is at this stage th.at males 

 and females are with certainty distinguishable for the 

 lirst time. 



The Male. The male tick emerges from his skin 

 as a iMown. oval tick, about one-tenth of an inch in 

 lenL^th. He has completed his growth and goes through 

 no mrtlier development. Later he shows great activity, 

 moving about more or less over the skin of the host. 



The Female. The female tick at the time of 

 niiuiliing is slightly larger than the male. She never 

 slii-ws much activity, seldom moving far from her 

 original point of .attachment. She still has to undergo 

 imi^t of her growth. After mating, the fem.ale increases 

 very rai'idly in size, and in from 21 to (JO davs after 

 becoming attjicheil to a host as a seed tick, she becomes 

 fuUy engorged and drops to the pasture, to start again 

 the cycle of development by laying eggs. 



SUMMARY OF LIFE HISTORY 



To sum np : on the pasture there are found thne stages of the tick— the engorged female, the egg, and the larva OT seed tick : and on the animal hccft 

 are also found three stages— the larva or seed tick, the nymph, the sexually mature advdt of both sexes, and in addition the engorged female. 



(The above Is an extract firom a Bulletin ixsued officially by the Dntted States Department of Agriculture, mtttUd— 

 " Methods of Rxterminatlng the Texas Fever Tick") 



COOPER'S CATTLE TICK DIP 

 Hai ncetoed the official approval of the following Countriea: 

 Unloo ol Soutb .Africa. Northern Rhodesia, Brazil, Basutoland, 



Nyasalaod, Swaziland, Southern Rhodesia, Madajiascar, 



British East .'tfrica, German East Africa, Portuguese East Atrica, 



Portuguese West Africa, Egypt, Argentine Republic. Queensland, 



United Slates of America, New South Wales, 



Northern Territory of Australia. 



WEST INDIAN AGENTS ; 



ST. KITTS : 5. L. Horslord & Co. ANTIGUA : Kennett, Bryson & Co. 



JA.MAICA: U. Henderson & Co., Kingston. 



(iKENAI)A: Thom.son, Hankev & Co. 



BARBAno.'i: Burbado.< Co-operative Cotton Co., Ltd. 



BAHAMAS: W. N. Twynam, Na.vsau. 



TRIMOAD: T. Oeddes Orant, Port of Spain. 



BI«iTISH (lUlANA: Sandbacli, Parker & Co. 



ST. VINCENT: Corea & Co., Kingstown, NtViS: S. I). Malone. 



DANISH W1:ST INDIES: A. Schmiejelow, St. Croix. 



MONTSI;RRAT: W. Llewellyn Wall. DO.MINICA: Hon.H. A, Frampton. 



ST. l.tlCIA: Barnard Sons & Co., Ca.strles. 



Manufacturers : WILLIAM COOPER & NEPHEWS, Berkhamsted, England. 



BRANCHES : Toroato, CLicago. Sydney, Melbourne, Auclilaad, Bueaoi Aire*, Moate Video, PuaU Ar*ia», East London, Odesia. 



