Epidemiological and identification study of sheep lice in Al-Mosul city

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1 Epidemiological and identification study of sheep lice in Al-Mosul city T. M. Al-Saffar B.A. Muhammad Coll. of Vet. Med./ Univ. of Mosul Abstract Four hundred and twenty sheep were examined for lice infestation from March 2005 to March 2006 with an age ranged from 1 5 years at different farms and areas and of different breeds in Al-Mosul city. 13%(55) of sheep were infested with different types of lice. The seasonal variation was noticed in this study, the highest infestation rate was in Winter 23.5%, and lowest in Summer 5.7%.The most observable clinical signs were obvious irritation, with pulled greasy wool, scratching, rubbing against walls and trees, loss of sleep, restless, fleece damage and pruritus. Heavy lice infestation with sucking type can cause anemia. Three degrees of lice infestation was observed (low, moderate, and heavy) depending on the number of lice or nymphs on the skin or wool. Microscopical classification of isolated lice revealed two types biting lice (Bovicola ovis and Bovicola pregratus) and three sucking lice of the following species (Linognathus stenopsis, L. ovillus, L. africanus). Lice are worldwide in sheep throughout the world (1). They are more active and reproduce most rapidly in cool condition (2). Sheep are parasitized by several species of sucking lice and biting (or chewing lice) which economically important. Lice have been known to be injurious itself to sheep on account of depresses wool production (3). Irritation due to rubbing, scratching, sucking of blood, epidermal scales, dermatitis and allergic responses (4). Leiper reported two species of lice in Iraq, the blue louse Linognathus africanus and biting lice Bovicola ovis (7). In Australia (6) reported that body lice of sheep are present on 1 30 % of animals. Heavy infestation is Samples were taken from 420 examined sheep of different areas and farms in Mosul city (Kokjalli, Rashediya and Hadbaa). This study extended from March 2005 to March Samples were collected from suspected wool and skin scales of infected animals using fine forceps, comb, brush and hand lens 10x, from neck, back, shoulder, hip or other The results in table (1) revealed that the prevalence of lice infestation in sheep was 13% (55 cases) of total 420 examined Introduction Materials and Methods Result 7 another possible cause of alopecia or anemia in sheep particularly in debilitated animals, malnutrition, and intestinal parasitism (5, 7).The purpose of this study is to investigate the prevalence of lice of sheep and identify the species, seasonal variation and severity of infestation. Lice infestation can be serious specially as some species are quite small and therefore easily overlooked, and as they can multiply enormously, by which time the animal may be so emaciated or anemic. When animals are poorly fed and kept in over crowded conditions and moderate temperature they often become severely infested with lice, and the number of adult parasites or nymphs are very large and enormous(8). parts of the body. Samples were kept in small Petri dishes or test tubes with few drops of 70 % alcohol (8). Estimation of the degree of infestation according to the number of lice, nymph or eggs (nits) on wool or skin. Sheep that were given drugs or dipping and shearing are not included in this study.microscopic classification of the identified lice according to (9, 10, 11, 13). sheep. There was seasonal variation noticed among these animals and highest infestation was in Winter 23.5%, Autumn

2 15%, Spring 8.1% and lowest in summer Figure (3) Linognathus africanus, Figure 5.7%. Light degree of lice infestation (4) Linognathus stenopsis and Figure (5) B. among examined animals were pergratus. The percentage of infestation predominant and common (number of lice with biting lice was 8%, and the 1 5 per inch square), moderate degree (6 percentage of infestation with sucking lice 20 lice) and heavy degree (more than 20 was 5%, while the total percentage of lice) in the lesion. Two species of biting infestation was 13%. Two species of biting lice 8% and three species of sucking lice lice have been identified B. ovis 6.4% and 5% which were identified (Table 1) in B. pregretus 1.6%. Three species of infested sheep.biting lice were smaller sucking lice have been detected, L. ovillus, than sucking lice, they were yellow and 3.6% L. stenopsis 1.2% and L. africanus have larger rounded head, wider than the 0.2% as seen in figure (1, 2, and 3). thorax. Biting lice have long legs.sucking Seasonal infestation with both types of lice lice (Linognathus species) have first pair of as seen in table (1) revealed that in the tarsal claws is smaller than the second and Spring 8.1%, in the Summer 5.7%, in the third pairs, and have more than one row of Autumn 15% and in Winter setae per abdominal segment. Sucking lice 23.5%.Clinically, infected sheep with lice were red to gray colour usually depends on shows irritation, restless, rubbing, biting, the amount of blood, and the head is and scratching. Sheep infested with narrow and pointed.figure (1) shows adult sucking lice showed signs of emaciation, louse L. ovillus (Sucking Louse) and figure poor condition, damage to the wool and (2) shows adult (Biting Louse) B. ovis. anemia particularly in Winter. Findings Table (1): Prevalence of sheep lice in Mosul Seasons No. of examined animals No. of positive % of infestation Biting lice No. of + ve Sucking lice No. of = ve Spring B. ovis 5 L. ovillus 4 Summer B. ovis 4 L. ovillus 2 Autumn B. ovis 8 B. pregretus 1 Winter * B. ovis 10 B. pregretus 3 L. ovillus 3 L. stenopsis 1 L. africanus 2 L. ovillus 6 L. stenopsis 4 L. africanus 2 Total % 8 % 5 % * Significant differentiation at p < The present results of this study has revealed that 13 % of the total number of 420 sheep examined were infested by light, moderate and heavy degrees of both biting (chewing) and sucking lice, Mallophga and Anoplura. The most common louse that infest sheep is the biting louse B. ovis (Body Louse). This louse is very small and more abundant on older sheep and animals in poor condition. It is very irritating parasite, this is in agreement with that of (11). In Mosul, several authors who Discussion recorded that sheep were infested by both sucking and biting lice(7). Significant difference of lice infestation in Winter months because direct contact, bad management and crowding are optimal for spread and proliferation of lice in crowded yards for a long period especially. This is similar to those reported by (7,9,10). B.ovis the brown body louse of sheep was predominant and usually infest the mid dorsal line and upper side of the body, while L.ovillus sucking blue face louse

3 occur on the head and on the hairy parts of invade the skin. Lice wth chewing mouth the lower body this in agreement with that parts live on epithelial debris, sebaceous research reported by (7.13).Typically, lice secretions and skin bacteria and may not demonstrated pronounced seasonal do so like other ectoparasite and cause variations and the numbers of lice being fewer systemic and pathological greatest in winter and lowest in Summer. effects.microscopic identification and This is in agreement of that of (12, 13, classification of these ectoparasites (lice) 14).Lousiness, achronic dermatisis of and most predominant species were the sheep is characterized by constant Biting lice: irritation, itching, restless, even though the B. ovis condition has high incidence it attracts B. peregritus little attention from producers, small Sucking lice: numbers cause no clinical manifestations, L. ovillus but the large number during winter cause L. stenopsis symptoms and some sheep may develop L. africanus anemia from prolonged sucking lice As shown in Fig (1, 2, 3).Among all infestation. The pathological effects are infested animals at all season, and sheep influnced by climate factors, and Summer may carry light infestation of lice without solar radiation kills adults and nymphs in showing noticeable symptoms.the 30 minutes at 48 C. The effect of lice is incidence of louse infestation among sheep usually a function of their density, and a differs from locality to another and in Iraq small number of lice may produce no the disease is still one of the important problem and do not often have a serious serious problems. This is in agreement effect from the pathologist's point of view. with that of (7). Since lice are superficial insects and do not Fig.(1):Adult lice L. ovillus (sucking lice) Fig.(2):Adult lice B. ovis (Biting lice) 9

4 Fig. (3):Linognathus africanus Fig. (4):Linognathus stenopsis Fig.(5):B.Pergratus References 1. Arundel, J.H. (1988).The life cycle, epidemiology and control of sheep lice. (Modified from paper 01 presented to the AWC lice control workshop. Melborn. 2. Bates, P.G. (1993). Veterinary Records (133):

5 3. Brightling, A.. (1989). Evaluation of 8. Morcomb, P.W. and Young, G.E. strategies for control of sheep lice (1993).Persistence of sheep body B. ovis with an epidemiological louce, Bovicola ovis after model. Australian Vet. J. Vol. treatment. Aust. Vet. J. (70). (66), No. 2: P Morcomb, P.W., Young, G. E. and Ball 4. Dwightd Bowman, MS, Randy Carl M.D. (1996). The detection of Lynn Markl Eberhard, (1999). lice (Bovicola ovis) in Mobs of Parasitology for Veterinarians. sheep. Australia. Vet. J. (69). P. Eighth Ed John Lasersen and Less Tohey, (1992). 10. Pugh, G.F. (2002). Sheep and Goat Control of ectoparasites in sheep. Medicine. First Ed.; P ISBN x. Victoria 11. Richard Wall and David Shearer, Congresses. (2001). Veterinary Ectoparasites. 6. Johnson, P.W. (1990). Ectoparasites in 2 nd Ed. Chapter 7. P Sheep Medicine. University of 12. Sinclair, A.N. (1986). Study of sheep Sydney Postgraduate Committee lice. Australian J. of Biological in Vet. Sciences, Proceeding No. Sciences; 38, , P Soulsby, E. J. L. (1982). Helminths, 7. Leiper, J.W.G. (1957). Report to the Arthroports and Protozoa of Government of Iraq on animal Domesticated Animals. Sixth Ed. parasites and their control. FAO, Baillierre, Tindal and Cassell. Rome, Ltd. دراسة وبائية وتشخيصية لقمل األغنام في مدينة الموصل طالل محمود الصفار بشار عبد الرحمن محمد كلية الطب البيطري/جامعة الموصل الخالصة شملت الدراسة فحص 021 رأسا من األغنام لتشخييص وتحديخد اصخابات ال مخل الميتلفخة فخا األغنخام بعمخر 0 إلخ 5 سنوات من ميتلف الح ول والمناطق واألجناس فا مدينة الموصل للفترة من شباط 2115 حت شباط كانخت نسخبة االصابة الكلية بال مل %01)55 حيوان مصاب مخن مجمخو 021( بكخال النخوعين مخن ال مخل العخا %8 والمخاص %5. أظهرت الدراسة أيضا وجود فروق معنوية فا نسبة اإلصابات الفصلية حيث لوحظ أن أعلخ نسخبة لاصخابة بال مخل كانخت فخا فصخل الشختا %2135 بينمخا ألخل نسخبة كانخت فخا فصخل الصخيف %537 أمخا أمخم التخرايرات المرضخية الواضخحة التخا لوحظت علخ األغنخام المصخابة فكانخت الحكخة واالاعخاو وف خدان النخوم وعخدم االسخت رار والتيخدق مخو تسخالط أو تلخف الصوف واحتكاك الحيوان باألشجار والجدران والحساسية كما وجد أن االصابات الشديدة بال مل المخاص تخيدي إلخ ف خر الدم وتواعت اإلصابات ما بين يفيفة ومتوسطة وشديدة.تم يالل مذه الدراسة تصخنيف وتحديخد نخو ال مخل المعخاول مخن الحيوانات المصابة حيخث لخوحظ أن ال مخل العخا lice( )Biting وياصخة نخو.B ovis مخو األكاخر إنتشخاران مخن ال مخل المخاص lice(.genus Linognathus )Sucking وان النخو 230 %وpregratus B. ovis %032 B. بينمخا ال مخل المخاص برنواعخا الاالاخة %032.L stenopsis%132.l ovillus وAfricanus %132.L علخ التوالا.اسختنتجت مخذه الدراسخة أن منالخك االاخة أنخوا مخن اإلصخابات مخن حيخث عخدد ال مخل فخا الصخوف أو الجلخد ومخا اإلصخابات اليفيفخة اخم المتوسطة واإلصابات الشديدة. 00