SKIN PARASITES IN SHEEP.

Wairarapa Daily Times, Volume 4, Issue 1043, 8 April 1882, Page 2

SKIN PARASITES IN SHEEP.

(From the N.Zi County Journal.) The loss of wool oaused by the skin parasites which infest our flocks in muoh greater than is generally supposed, Be-. sides the wool actually shed; and loss by rubbing, there is the far more serious loss occasioned by the conatant irritation and inflammation of the skin, set up by those parasites, which cause the ishedp to lose condition; the growth ofwobLtechecked, and a loss in quantity, as wellllfleterior. ation in quality, is the result, Thiß is not the only loss sustained by the owners of sheep infected with these insects. The sheep being always in a resfless state, wander about pastures, cjeatFoyijjg jjeayly aq gvasj a(Mwy they rub agbipat the fences,; breaking wires, and causing gaps ; the result being th§ continual straying, and mixing with other jjpoks, whiph is one of tl)e greatest gnaoy-sheep-breeder hap tq -conten^ With. T . '/;!' , " In the spipg tpoj lqng-woftllejj ehggp, being heavy in fleeoe, re<jmre'the pot), stant attentionpt a Bhepherd, on account of their liability to get cast on their baoks, and a considerable number of sheep are lost every season from this cause, which is mainly due to lice and ticks'. These very serious losses may, in a great measure, be avoided, and I write this paper in the hope that by drawing the attention gf jtoc]{ow)|ej's'to'|hp subjefitj induced to take the necessary' mgasureq foy coping with this growing evil,' The three skjn parasites wl)ioh attack sheep in I<pw Wand: are i the scab, tiie louse and the tick. Until quite recently the scab has undoubtedly been the most formidable of these, but there iB a good reason to hope that the day is not far distant, when our flocks will be entirely free from this pest. Of the 14,000.000 sheep in New Zealaud thero wore about 700,000 infected with scab, on the" 31st • December last, beiug some 200,(jra lpas'than'at thjhante (Jfjte it*' the preyiojjls yea}', |nd" thir'mpiWv ja rapiil!| beingrqduce'd. 1 TJie sheep louso hi 43 fa' l ' to giye alnjoqt as ipch trouble as tl)e seal). Ala cqnjparfttively repeat impoj;t|: tion, its incyeasp has heen so rapid, thjt $ crofls-bred or long-woolledilookfree iron) lice is now the exception, The sheep tick although troublesome enough, is not to bo compared with tho acarf or the lice, for the damage it causes.

These three parasites produce in a different degree much the same effect on the sheep, i.e., intense irritation of the skin,accompanied with loss of wool and condition. The scab aooari, burrow into the skin, wher'o they 1 Jii'eed, dAd'causoan eruption of the sltin hardens into a thick scab; the lice and ticks cause 1 ' a very slight eruption, and bresOv tlw WOOl,'"" 1 . 1 ->• lij'thls paper I propose to speak pattioularly of the sheep louse, as i) Is] probably the least known,' anil it is', thel parasite whioh we liave the most to* featl in the future, as jt is undoubtedly,gain!® ground, The popular? impression wiffl| «d to lice in'animals is, that they are the result of poverty' of the 'blood, but scjentif|c ijjenqf the present day te'll iw there is iio suoh thing'as sjiontanebui generation, that animals irifeoted witlr parasites must have previously coitie in contact with the germs of the insect. However this may be in tho case of lice in horses and rattle;'l fhinlctliat the followintf faflf, wtiicli I bajiove is undisputed, goes a groat way towards proving the gejm theory in tWcase office in slleepV (he sheep louse'did notappear'iu this country until some eight online months 'ago, when it is supposed to have been introduced in some imported' long-woolled rams. Although prior to that ditto sheep wpfe'in Djaiiy kept in iusUs poverty-efpeket} a stijteaawp ocoaaion&ljjr see 'them now, sheep'in low qonditiorv did not then, nor do they now', neqessarlly breed lice. It is also generally believed that _ liee confjne themselves, to .lowcomtyjoned animals. From my ow 11 observation, I am inolinod to belitvo that they are to ]}o found 011 mpat tynimffi. irrespective qf condition, but tl'iey dq no t thrive and increase, and' consequently ajiq not noticed on perfectly healthy' and well doing animals. One instance I know of, a flock of Leicester pvyea lyhjch' w§r§ pgoj; and very bad \yith lice, they wore "put pi) to good food, and in a few months l)a(f apparently tljrowi) of the ijee qntl looking well. A little later, being allowed to go back in condition, thoy became worse than ever, the lice litorally swarming over them. I had frequent opportunities of examining these sheep, ai)d whpn thpy were lookijig at their best, I poult} always lj'ctj, " " "V-.-Sheep lice begin to die qff ahout the end of October, f hen tl)e weather com- ; mencea tq get warm. I tljink tips may bp attributed to {he yolk rising niorp freplv at this time of tho yoav, and choking tho air passages of the insect, Both lice and ticks disappear when sheep are alorii. apparently beoauao there is uot sufficient shelter left for them; they, leave the ova attached to the wool, and about February, when there is sufficient length of wool to shelter them, the young insects appear. Lice are not readily detected until about April, when loose wool may bo seen to rise on the back; this is caused by the insoct cutting the fibres of the wool, near the skin, with the sharp nippers with whiqh it is furnished; this loose wool is soon rubbed off, and 4 hate patch amtjatL which gradually enlarges as the insects increase, until, as I have seen in some oases, a fourth or more of the wool Is lost. . . ?

All classes of long-woolled and crossbred Bheep are subject to lice, but it" i, rarely found on the merino, the density of the wool, and abundance of yolk in the merino, may possibly account for this, The old saying " if a thing is worth doing! it la worth doing well," which is appli' cable to farming, applies equally well to the management of stock ; it ia juat as necessary for the farmer to keep'his sheep in good order, as it is for him to keep his land m good heart. As with the land so W! h the sheep, the bete attention the get the better the result. There is no doubt, that as long as sheep are kept im realty good condition, they will keep com ' paratively free from lice and ticks, but stock-owners cannot always do this, the seasons her? are so variable that no one can calculate'with any certainty, as to whjfG aWunt of Mock his farm'will carry ' i administered, is a certain, cure formal | P"*# 8 :, S °!PB diversity of opinion exists as to the best time to do this; dippin'a off the shears is advocated by soie, Mat this time less material is required, but it | W extremely doubtful whether any ordin. m dtp will destroy the ova, unless the dip IS kept hot, which adds considerably to the expense. The more general mm, floe is to dip about March or April, when te,^ ln l l We,wool, .the dipping material will remain a longer time, aot^

and will yrobably lie sufficiently strong to kill the young insects as they hatch out. Auothor reason in favor oWippmg at this time is, that the favmeiMving bought his stock for the ■winter, \v!jj Hot be so likely to re-infect Ibis flook by sheep purchased through the public saleyards, which pro almost auro to be infected with lice.

Dipping to be of real good should be universal, it'is very discouraging for a ebeepownor who lias gono to llio troublo Mid oxpenao of dipping his llock to find his neighbors' infected sheep mixed with his own. The cost of dipping is about lia per Load, and wlion it is considorod / V ol ' Rmri " cos 'i "10 shoop aro freed from tln-so pests, and consequently no " 1 ' 11 K to worry them, aro enabled to faco the winter in good heart and m addition thrive, and do not troublo the fences, and tho loss of wool ia avoided thete can be no question ns to tlio wisdom of dipping; and no stock-owner should hesitate to do so. There aro various compounds sold for dipping, most of which m,!> t1 efficacious if used with cold water; I should strongly advise thoso who can procure fucht a reasonable coat, to d!n 1! ?' of Wby.'9° degrees; a waim Z 0 rf Peiißtrating, and is more Km 1 ytheora of " 10 parasites. LSi m SO r n e , COIUUkMuI those interested to watoh the eflect of the various dips on heir own and their neighbors' flocks; and tp choose that dip which, while destroyinßttio parasites effectually, leaves tho least stain in the wool. It Would greatly facilitate tho dipping of sheep m agricultural districts, , if dips were erected by private enterprise, at the yapUß centres, where farmers could get their smaMocks dipped for a moderate charge. y e ry small flocks do not warrant We pppessary outlay, juid in other instances, want of water is tlio diffiouHy. There is but little doubt, that if these amenities were overcome by somo such means as I have suggested, dipping sheep would becomo much more general, to the decided advantage of tho owner, and the country at largo. Reginald Fostkk, ' Amjjp'rlpy.