EVALUATION OF SERUM SIALIC ACID AND ADENOSINE DEAMINASE ACTIVITY AS A DIAGNOSTIC INDICATORS FOR BABESIOSIS (B.OVIS) WITH SOME CLINICAL AND BIOCHEMICAL STUDIES IN SHEEP NATURALLY INFECTED WITH BABESIA IN ISMAILIA GOVERNORATE

Document Type : Research article

Author

Animal Health Research Institute, Ismailia.

Abstract

The study was conducted on one hundred and ten adult sheep from private farms in different localities in Ismailia Governorate. Which Ninty sheep were naturally infected with Babesia ovis and Twenty sheep were proved by clinical and laboratory method to be healthy and used as control. The clinical signs of diseased sheep revealed a marked hyperthermia, loss of appetite, depression, weakness, cessation of rumination, extreme pale mucus membrane due to severe anaemia, increased respiratory rate and labored breathing. The urine was dark red to brown coloration and later on jaundice subsequently developed. The biochemical data reveled that a highly significant increase of both serum sialic acid and adenosine deaminase activity in infected sheep in comparison with healthy one. In addition total bilirubin, direct and indirect levels were highly significant increase in infected sheep when compared with the healthy one. Total protein was significantly decreased with hypo-albuminaemia, while globulin, glucose and cholesterol were non-significantly increased. Blood serum calcium and sodium levels showed a significant decreased, while serum level of inorganic phosphorus was significantly increased in infected animals. Blood serum iron revealed highly significant elevation, while copper and zinc levels showed highly significant decreased. Also significant increase in AST, ALT and AP were evident in infected sheep comparatively with control.

Keywords


Evaluation of serum sialic acid and adenosine deaminase activity as a diagnostic indicators for Babesiosis (B.ovis) with some clinical and biochemical studies in sheep naturally infected with Babesia in Ismailia Governorate

 

S.M. Ismail

 

Animal Health Research Institute, Ismailia.

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                                          ABSTRACT

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Received at: 18/3/2012

 

 

Accepted:3/5/2012

 

 

The study was conducted on one hundred and ten adult sheep from private farms in different localities in Ismailia Governorate. Which Ninty sheep were naturally infected with Babesia ovis and Twenty sheep were proved by clinical and laboratory method to be healthy and used as control. The clinical signs of diseased sheep revealed a marked hyperthermia, loss of appetite, depression, weakness, cessation of rumination, extreme pale mucus membrane due to severe anaemia, increased respiratory rate and labored breathing. The urine was dark red to brown coloration and later on jaundice subsequently developed. The biochemical data reveled that a highly significant increase of both serum sialic acid and adenosine deaminase activity in infected sheep in comparison with healthy one. In addition total bilirubin, direct and indirect levels were highly significant increase in infected sheep when compared with the healthy one. Total protein was significantly decreased with hypo-albuminaemia, while globulin, glucose and cholesterol were non-significantly increased. Blood serum calcium and sodium levels showed a significant decreased, while serum level of inorganic phosphorus was significantly increased in infected animals. Blood serum iron revealed highly significant elevation, while copper and zinc levels showed highly significant decreased. Also significant increase in AST, ALT and AP were evident in infected sheep comparatively with control.

 

تقييم حمض السياليک ونشاط انزيم الادينوسين دى امينيزککواشف تشخيصية للبابيزيا مع دراسات اکلينيکية وبيوکيميائية فى مصل دم الاغنام المصابة طبيعيا بالبابيزيا بمحافظة الاسماعيلية

 

صلاح محمود خليل اسماعيل

 

 يعد مرض حمى البول الدموى (البابيزيا) عند الاغنام احد الامراض الناجمة عن الاصابة بالاوليات ويسبب هذا المرض طفيليات بذرية وحيدة الخلية صغيرة الحجم تنتمى الى جنس البابيزيا. وقد اجريت الدراسة على عدد90  من الاغنام المصابة طبيعيا بالبابيزيا بالاضافة الى عدد20  من الاغنام السليمة واستخدمت کضابط للتجربه. تتميز اعراض هذا المرض بارتفاع شديد فى درجة حرارة جسم الحيوان مع فقدان للشهية وتوقف الاجترار وهزال وضعف مع هبوط عام وزيادة عدد دقات القلب وصعوبة التنفس مع ظهور يرقان على الاغشية المخاطية وتلون البول باللون الاحمر الداکن. وقد اظهرت نتائج التحاليل البيوکيميائية لمصل دم الاغنام المصابة الى زيادة معنوية فى مستوى کلا من حمض السياليک ونشاط انزيم الادينوسين دى امينيز والبيلوروبين الکلى والمباشر والغير مباشرونقص معنوى فى البروتين الکلى والالبيومين بالاضافة الى وجود انخفاض معنوى لکل من الکالسيوم والصوديوم مع زيادة فى الفوسفور کما وجدت زيادة معنوية عالية فى عنصر الحديد بينما انخفض مستوى کلا من النحاس والزنک کما اظهرت الدراسة ايضا وجود زيادة معنوية فى مستوى کلا من انزيم الاسبرتات امينو ترانسفيريز والالکلين فوسفاتيز. ان اصابة الاغنام بحمى البول الدموى يسبب خسائر اقتصادية کبيرة وهذا يتطلب بذل جهود کبيرة للتحکم ومن ثم التخلص من هذا المرض. لذا ينصح باجراء مکافحه دورية للقراد بالمبيدات الحشرية غير الضارة بصحة الحيوان والبيئة لان القراد يقوم بدور الناقل لمرض حمى البول الدموى.

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Key words: Babesia, sheep, sialic acid, adenosine deaminase activity.

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INTRODUCTION

 

Diseases of small ruminants are among the least recognized problems in veterinary science, this is true especially for tick-born diseases of sheep (Friedhoff, 1997). Babesia is one of the most important dieases in the tropical and subtropical countries. The severity of the disease increases with the long exposure to stress factors, which lower the productive performance of the animals. Ramadan and Lubna, (2000), Radwan and Ali, (2004) and Sulaiman et al. (2010).

 

Babesia species are intraerythrocytic protozoan of domestic and wild animals caused anaemia and hemoglobinuria. Among the babesia species affecting small ruminants and incriminated for major economic losses, such loss result from deaths of affected sheep, unthriftiness of chronic cases and cause the greatest economic losses in sheep and goat production (Radwan and Ali, (2004); Sulaiman et al. (2010).

 

Sheep Babesiosis caused by Babesia ovis and Babesia motasi in the area infested with Rhipicephalus bursa, morbidity and mortality due to Babesiosis in sheep corresponded closely to the seasonal activity of vector Rhipicephalus bursa, the peak was in summer followed by spring (Ramadan and Lubna, 2000; Yasin, 2003).

 

Sialic acid (SA)an acetylated derivative of neuraminic acid, is widely distributed in mammal tissues and body fluids.

 

The majority of sialic acids are found in either protein or lipid bounded formes, while little amount is in the free forms (Col and Uslu, 2007). Therefore, the detection of sialic acids be a valuable indicator for diagnosis and prognosis of inflammatory diseases (Motoi et al., 1984).

 

While Adenosine Deaminase (ADA)is an enzyme that is present in all cells. ADA activity is elevated in many diseases where cellular immunity is stimulated (Ustundag et al., 1999). Measurement of ADA is used for the diagnosis and monitoring of autoimmune and inflammatory diseases because of its easy identification, high sensitivity and low cost (Maldhure et al., 1994).

 

The aime of the present study was oriented to evaluate the host immune response by the use of serum total sialic acid and ADA activity in sheep naturally affected with babesiosis and investigate the effect of naturally infected sheep with Babesia upon observed clinical signs and some serum biochemical parameters.

 

Materials and Methods

 

І- Animals: One hundred and ten adult sheep of both sex, 2-5 years old and 35 - 55 Kg body weight from a private farms in different localities in Ismailia Governorate. Where as Ninty sheep were naturally infected with Babesia ovis, in addition to Twenty sheep were clinically healthy used as control. All animals were subjected to careful clinical and laboratory investigation to insure their healthy status according to Pugh, (2002).

 

ІІ- Samples:

A- Blood smears: Thin blood smears were collected from the ear vein of all the examined animals and individually prepared. Fixed blood films were stained with Giemsa stain for identification of blood parasite that carried out in parasitology department, Faculty of Veterinary Medicine, Suez Canal University, according to Meyer et al. (1992).

 

B- Blood samples: were collected from the jugular vein in dry sterilized clean centrifuge tubes from each animal and allowed to clot at room temperature, then centrifuged at 3000 r.p.m for 20 minutes to separate clear non-hemolysed serum. Firstly, serum samples were colorimetrically analysed using test kits (Bicon–Germany) for measuring glucose levels as soon as possible. While the collected clear sera were kept at -20Ċ till used for biochemical assay. Serum Sialic acid was measured according to the method reported previously by Sydow et al. (1988) while Adenosine deaninase activity (ADA) was determined by the use of the Giusti method (Giusti and Galanti, 1984) a colourimetric method based on the principle of measuring absorbance of the coloured indophenole complex at 628 nm.

 

Blood serum cholesterol, total bilirubin, direct bilirubin, total protein, Albumin, AST, ALT, ALP, Calcium, Phosphorus and Magnesium  were determined spectrophotometrically used standarised test- kits supplied from Bio- Merieux (Bains/France).   

 

Serum copper, Iron and zinc levels were determined using atomic absorption spectrophotometrically (Perkin Elmer Model 2380 USA) In Ismailia Agriculture Research Institute, Soil and Irrigation Department.

 

Blood serum indirect bilirubin, globulin and albumin/ globulin ratio were calculated mathematically.

 

ІІІ- Statistical analysis: The obtained data was subjected to software program according to Selvin, (1996) to study the effect of Babesiasis on some serum biochemical parameters.

 

RESULTS

 

Clinically infected sheep showed different signs graduated from marked increase of temperature, loss of appetite, depression, weakness, emaciation, extreme pale mucous membrane, increased respiratory rate, labored breathing, haemoglobinuria, where the urine was dark red brown color and jaundice subsequently developed.

 

As well as presence of ticks (Rhipicephalus spp.) were detected on different parts of the body. Examination of blood films of diseased sheep revealed infection with Babesia ovis.

 

The results of biochemical analysis of blood sera of infected and controlled sheep are illustrated in Tables (1, 2, 3).

 

 

 

Table 1: Effect of Babesia ovis infection on some serum biochemical parameters in sheep.

         

Infected sheep with Babesia    n=90

Clinically healthy sheep    n=20

Parameters

75.60±2.75 ***

59.82 ± 2.34

Sialic acid(mg/dl)

16.52±2.60 ***

7.64± 0.3

Adenosine deaminase

(U/L)

59.8±2.9

52.20± 3.6

Glucose(mg/dl)

142.7±5.2

135.92±4.5

Cholesterol(mg/dl)

1.45±0.23 **

0.43±0.05

Total bilirubin(mg/dl)

0.28±0.06 **

0.14±0.02

Direct bilirubin(mg/dl)

1.17±0.17 **

0.29±0.03

Indirect bilirubin(mg/dl)

6.44±0.07 *

7.45±0.05

Total protein(gm/dl)

1.96±0.03 *

3.26±0.02

Albumin(gm/dl)

4.48±0.04

4.19±0.03

Globulin(gm/dl)

0.44±0.75 *

0.78±0.67

A/G ratio %

 

The obtained results were mean ± SE.

* Significant at (P<0.05).

** Highly Significant at (P<0.01)

*** Very highly significant at (p<0.001)

 

Table 2: Effect of Babesia ovis infection on some blood serum biochemical macro and micro elements in sheep.

 

 

Infected sheep with Babesia       n=90

 

Clinically healthy sheep        n=20

 

Parameters

7.2±0.35 *

10.21±0.23

Calcium        (mg/dl)

8.45±0.50 *

6.85±0.90

Inorganic phosphorus           (mg/dl)

2.71±0.16

2.56±0.25

Magnesium  (mg/dl)

130.80±2.10 **

147.24±2.30

Sodium         (mmol/L)

5.86±0.17

5.72±0.15

Potassiumm (mmol/L)

253.70±8.11***

148.60±6.84

Iron                (µg/dl)

67.52±4.30 **

94.10±4.27

Copper          (µg/dl)

71.75±3.20 **

95.42±4.30

Zinc              (µg/dl)

 

The obtained results were mean ± SE.

*  Significant at (P< 0.05)

**  Highly Significant at (p< 0.01)

***  Very highly Significant at (p<0.001)

 

Table 3: Effect of Babesia ovis infection on some blood serum enzymes in sheep.

 

Infected sheep with Babesia     n=90

Clinically healthy sheep       n=20

Parameters

63.92±4.13 **

48.75±2.8

A S T   (I.U/L)

47.26±3.84 **

26.3±1.92

A L T  (I.U/L)

145.52±3.22 ***

119.64±4.30

ALP   (I.U/L)

 

The obtained results were mean ± SE.

** Significant at (P<0.01)

*** Very highly significant at (p<0.001)

                                                                                                     


Discussion

 

Babesia is a small protozoan found in vertebrates red blood cells. This protozoan can be found in many species of animals such as cow, sheep, goat, pig, horse and buffalo. Babesiosis is an acute hemolytic feverous disease which is more prevalent in domesticated animals and transmitted by hard tick's bite, prevalence of this disease in tropical and subtropical regions is more and it causes severe loss of sensitive animals,(Seyyed et al., 2011).

 

Mortality of this disease in absence of treatment in case of Babesia ovis infection may reach 70% - 80% in sheep, (Hosseini, 2003).

 

The difference of severity of the disease may attribute to the higher incidence of tick vectors and the change in husbandry, climatic condition and control of ticks with respect to the seasonal variation that the peak was in summer followed by spring that agreed with Yeruham et al. (1998), Ramadan and Lubna, (2000).

 

Clinical examination among diseased sheep showed that the affected sheep had marked increase of temperature, loss of appetite, emaciation, pale mucus membranes, jaundice dry muzzle and cessation of rumination, increased respiratory rate, muscle tremors in addition to the urine was dark red to brown in color due to hemoglobinuria in the final stages. Similar signs were recorded by El-Sawahly (1999); Omran and Abd El-Azeim (2000); Radwan and Ali (2004); Sulaiman   et al. (2010).

 

Serum biochemical changes in sheep infected with Babesia ovis has been documented. The results revealed that increased level of serum sialic acid concentration in sheep infected with Babesia ovis in comparison with the control group.

 

The results of the present study are similar to the previous reports by Ertekin et al. (2000); Karagenc et al. (2005). The elevation of serum sialic acid concentrations in sheep with Babesiosis may represent the host immune response to the parasite, where the increased level of sialic acid may alter receptor-ligand interactions, which are known to play an important role in inflammation and immune response (Karagenc et al., 2005).

 

In addition the release of sialic acid from the glycolipids or glycoproteins of the lysed cell membrane surfaces may result in the elevation of serum total sialic acid level in infected sheep.

 

Serum Adenosine deaminase levels was significantly higher (P< 0.001) in the infected groups in contrast to the control group. This increase in serum ADA levels may result from the phagocytic activity of macrophages and / or erythrocyte damage caused by the parasite (Ustundag et al., 1999).

 

Babesia ovis infection induced marked and persistent elevations of serum total sialic acid concentration and serum ADA suggesting that these indicators would indirectly promote the invasion and presence of the parasite in the host. These results were in agreement with Deger (2007).

 

Non-significant increase in serum glucose and cholesterol were observed in infected sheep in comparison to healthy animals. These findings indicating liver disease and nephrotoxic syndrome. Similar results were previously obtained by Abou EL-Naga (2002); Radwan and Ali (2004).

 

The results indicated also that, highly significant increase in total bilirubin (direct and indirect) in infected sheep comparatively with healthy animals. These results emphasize liver damage and increased in the indirect bilirubin was due to erythrocyte haemolysis (Jain, 2000). Similar results were reported by Yeruham et al. (1998); Abou El-Naga, (2002); Sulaiman et al. (2010).

 

Total protein and albumin were significantly decreased, these results may be due to destructive effect of Babesia on liver cells producing liver damage resulting in impaired synthesis of total protein and albumin from the liver (El-Sawahly, 1999)or due to renal insufficiency caused by the nephrotoxic effect when hemoglobin released from the ruptured red blood corpuscles due to parasite multiplication. These results agreed with those reported by Abou El-Naga (2002); Sulaiman et al. (2010).While non-significant  increase in serum globulin level in infected sheep was attributed to immune response of  animal  body to the infection Omran and Abd El-Azeim (2000); Rdwan and Ali (2004).

 

The effect of Babesia on serum calcium and sodium levels showed a significant decrease while serum level of inorganic phosphorus was increased in infected animal in comparison to healthy one.

 

The obtained results may be due to renal insufficiency caused by the nephrotoxic effect of hemoglobin that results from the rupture of red blood corpuscles due to parasite multiplication, also by liver involvement and anorexia for hypocalcaemia as well as the haemolytic nature of anaemia.

 

The obtained results coincided with those previously observed by Habela et al. (1991); Abou El-Naga (2002). On the other hand, no significant difference in serum potassium and magnesium levels were observed. Such results agree with Abou El-Naga (2002).

 

Blood serum iron level revealed highly significant elevation, these results were similar reported by El-Saifi et al. (1990); Omran and Abd El-Azeim (2000). Who attributed this alterations to the intra-vascular hemolysis. Blood serum copper and zinc showed highly significant decrease which may attributed to liver and bone marrow involvement as well as copper depletion(Ceci et al., 1997).

 

A highly significant increase in Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and Alkaline phosphatase (ALP) were observed in infected sheep in comparison to healthy one.

 

Such elevation was due to cellular damage caused by Babesia organisms lead to intravascular hemolysis which lead to anoxia and inflammatory lesions in various organs especially liver and kidneys causing nephrotoxic effects and lysis of erythrocytes during Babesia infection, these results were agreed with the results obtained by Radwan and Ali (2004); Sulaiman et al. (2010) in similar condition.

 

Finally, it may concluded that, the increased levels of serum sialic acid and Adenosine deaminase activity may mimic induced host immune response. Where Babesia ovis caused several pathological effects in many organs and tissues specially liver and kidneys to the animal host which lead to biochemical, metabolic and electrolytes disorders in blood serum of the affected animals.

 

The increased levels of serum sialic acid and adenosine deaminase activity may be used as a diagnostic indicators in diagnosis of Babesiosis in sheep, but these elevations are not definite diagnosis for Babesiosis because it may be increased also in many other disease conditions. 

 

So, it must be kept in mined that while treatment of diseased animals by eradication of ticks associated with additional treatment containing mineral mixture and injection of electrolytes solutions.

 

Acknowledgement

Researcher would like to sincerely thank Dr. Eman M. Youssef, Assistant professor of Parasitology, Faculty of Veterinary Medicine, Suez Canal University who help me in this study.

 

REFERANCES

 

Abou El-Naga, T.R. (2002): Effect of Babesiasis on some serum biochemical parameters in sheep and goats in Matrouh Governorate. 10th Sci. Cong. Fac. Vet. Med. Assiut Univ., Egypt 236–247.

Ceci, I.; Kivan, E.; Garcth, G.; Sasanelli, M. and Sparagno, L. (1997): Evidence of theileria infection in cattle and sheep in Italy. Vet. Rec. 140: 581–583.

Col, R. and Uslu, U. (2007):Changes in selected serum components in natrally infected with Theileria annulata. Bull. Vet. Inst. Pulawy. 51: 15-18.

Deger, Y.; Mert, H.; Dede, S.; Yur, F. and Mert, N. (2007): Serum total and lipid-bound sialic acid concentrations in sheep with natural Babesiosis. Acta. Vet. Brno, 76: 379–382.

El-Saifi, E.A.; Neweehy, T.K.; Nabila, S.D.; Abdu, O.M. and Halla, A.A. (1990): Studies on serum biochemistry of sheep infected with piroplasmosis in Egypt. 4th Sci., Cong. Fac. Vet. Med. Assiut Univ.

El-Sawahly, A.A. (1999): Veterinary infectious disease: A Practioners and students guide. 2nd Ed. Al-Ahram dist. Agency Egypt. PP. 401–409.

Ertekin, A.; Keles, I.; Ekin, S.; Karaca, M. and Akkan, H.A. (2000): An investigation on sialic acid and lipid-bounded sialic acid levels in animals with blood parasites: J. Fac. Vet. Med. Univ Yuzuncu Yil, 11: 34-35.

Friedhoff, K.T. (1997): Tick-borne diseases of sheep and goats caused by Babesia, Theileria or Anaplasma spp. Parasitologia 6 (39): 2: 99–109.

Giusti, G. and Galanti, B. (1984): Colorimetric method. In: Bergmeyer, H.U., Ed. Methods of Enzymatic Analysis. Verlag. Chemie. Weinheim. 315–323.

Habela, E.; Reima, D.; Navarrete, I.; Redondo, E. and Nieto, C.G. (1991): Histopathological changes in liver of sheep experimentally infected with Babesia ovis, Vet. Parasitol. 38: 1–12.

Hosseini, H.S. (2003): Parasitic infections of domesticated animals.Tehran University press, Tehran, Iran, PP: 61–65.

Jain, N.C. (2000): "Schalm's Veterinary Haematology" 8th Ed. Lea and Febiger, Philadelphia, U.S.A.

Karagenc, T.I.; Kiral, F.K.; Seyrek, K.; Bildik, A. and Eren, H. (2005):Detection of serum total sialic acid in cattle with natural tropical theileriosis. Revue Med. Vet., 156: 578–582.

Maldhure, B.R.; Bedarkar, S.p.; Kulkarnl, H.R. and Paplnwar, S.P. (1994):Pleural biopsy and adenosine deaminase in pleural fluid for the diagnosis of tubercular pleural effusion. Ind. J., Tuber, 41: 161–165.

Meyer, D.J.; Coles, E.H. and Ricin, L.J. (1992): Veterinary Laboratory Medicine, Interpretation and diagnosis. 1st Ed. W.B. Saunders Company Philadelphia and London. Toronto, Montreal, Sydny Tokyo.

Motoi, Y.; Kimura, Y.; Wakamatsu, H. and Shimbayashi, K. (1984): Determination and clinical evaluation of sialic acid and mucoprotein in bovine blood. Natl. Inst. Anim. Health, 37: 643–649.

Omran, H.H. and Abd El-Azeim, A.M. (2000): Studies on some hematological and serum biochemical changes in blood of sheep naturally infected with piroplasmosis in Sharkia Governorate. J. Vet. Med. Res. Vol. џ, No. ∏. 25–36.

Pugh, D.G. (2002): "Sheep and Goat  Medicine" 1st ed. W.B. Saunder Company. p 149-153.

Radwan, M.E. and Ali, A.A. (2004): Clinical and biochemical studies in sheep naturally infected with babesia in Assiut Governorate. Beni-Suef Vet. Med. J. Vol. XIV NO. (1) 7: 21-28.

Ramadan, M.Y. and Lubna, M.A. (2000): Studies on sheep Babesiosis in Kalubyia Governorate, Egypt. Minufia Vet. J. Vol. 1 No. 14: 147–155.

 

 

 

 

 

 

 

 

 

 

 

 

 

Selvin, W. (1996): Statistical analysis of epidemiological data 2nd Ed. Oxford University. Pp. 44-78.

Seyyed, R.Z.; Behzad, E. and Mohammad, R.Y. (2011): Study of the prevalence of Babesiosis in domesticated animals with suspected signs in Mazandaran Province, North of Iran, During 2008. Journal of Animal and Veterinary Advances 10 (6): 712–714.

Sulaiman, E.G.; Arslan, S.H.; Al-Obaidi, Q.T. and Daham, E. (2010): Clinical, haematological and biochemical studies of babesiosis in native goats in Mosul. Iraqi Journal of Veterinary Sciences 24(1): 31-35.

Sydow, G.; Wittmann, W.; Bender, E. and Starick, E. (1988): The Sialic acid content of the serum of cattle infected with bovine leukosis virus. Arch Exp. Veterinarmed 1988, 42: 194–197.

Ustundag, B.; Canatan, H.; Bahcecioglu, I.H.; Ozercan, I.H. and Cinkilinc, N. (1999): Serum adenosine deaminase activity levels in rats with experimentally- induced cirrhosis. Turk. J. Biochem. 24: 16–220.

Yasin Al-yassino, (2003): Serological study on babesia in Awassi sheep. J. of Al-Baath University 25 (2): 267–279.

Yeruham, I.; Hadani, A.; Galker, F.; Avidar, Y. and Bogin, E. (1998): Clinical, Clinico-pathological and serologicalstudies of Babesia ovis in experimentally infected sheep. Zentralbl Veterina. (B) Sep. 5, 7: 385–394.

REFERANCES
 
Abou El-Naga, T.R. (2002): Effect of Babesiasis on some serum biochemical parameters in sheep and goats in Matrouh Governorate. 10th Sci. Cong. Fac. Vet. Med. Assiut Univ., Egypt 236–247.
Ceci, I.; Kivan, E.; Garcth, G.; Sasanelli, M. and Sparagno, L. (1997): Evidence of theileria infection in cattle and sheep in Italy. Vet. Rec. 140: 581–583.
Col, R. and Uslu, U. (2007):Changes in selected serum components in natrally infected with Theileria annulata. Bull. Vet. Inst. Pulawy. 51: 15-18.
Deger, Y.; Mert, H.; Dede, S.; Yur, F. and Mert, N. (2007): Serum total and lipid-bound sialic acid concentrations in sheep with natural Babesiosis. Acta. Vet. Brno, 76: 379–382.
El-Saifi, E.A.; Neweehy, T.K.; Nabila, S.D.; Abdu, O.M. and Halla, A.A. (1990): Studies on serum biochemistry of sheep infected with piroplasmosis in Egypt. 4th Sci., Cong. Fac. Vet. Med. Assiut Univ.
El-Sawahly, A.A. (1999): Veterinary infectious disease: A Practioners and students guide. 2nd Ed. Al-Ahram dist. Agency Egypt. PP. 401–409.
Ertekin, A.; Keles, I.; Ekin, S.; Karaca, M. and Akkan, H.A. (2000): An investigation on sialic acid and lipid-bounded sialic acid levels in animals with blood parasites: J. Fac. Vet. Med. Univ Yuzuncu Yil, 11: 34-35.
Friedhoff, K.T. (1997): Tick-borne diseases of sheep and goats caused by Babesia, Theileria or Anaplasma spp. Parasitologia 6 (39): 2: 99–109.
Giusti, G. and Galanti, B. (1984): Colorimetric method. In: Bergmeyer, H.U., Ed. Methods of Enzymatic Analysis. Verlag. Chemie. Weinheim. 315–323.
Habela, E.; Reima, D.; Navarrete, I.; Redondo, E. and Nieto, C.G. (1991): Histopathological changes in liver of sheep experimentally infected with Babesia ovis, Vet. Parasitol. 38: 1–12.
Hosseini, H.S. (2003): Parasitic infections of domesticated animals.Tehran University press, Tehran, Iran, PP: 61–65.
Jain, N.C. (2000): "Schalm's Veterinary Haematology" 8th Ed. Lea and Febiger, Philadelphia, U.S.A.
Karagenc, T.I.; Kiral, F.K.; Seyrek, K.; Bildik, A. and Eren, H. (2005):Detection of serum total sialic acid in cattle with natural tropical theileriosis. Revue Med. Vet., 156: 578–582.
Maldhure, B.R.; Bedarkar, S.p.; Kulkarnl, H.R. and Paplnwar, S.P. (1994):Pleural biopsy and adenosine deaminase in pleural fluid for the diagnosis of tubercular pleural effusion. Ind. J., Tuber, 41: 161–165.
Meyer, D.J.; Coles, E.H. and Ricin, L.J. (1992): Veterinary Laboratory Medicine, Interpretation and diagnosis. 1st Ed. W.B. Saunders Company Philadelphia and London. Toronto, Montreal, Sydny Tokyo.
Motoi, Y.; Kimura, Y.; Wakamatsu, H. and Shimbayashi, K. (1984): Determination and clinical evaluation of sialic acid and mucoprotein in bovine blood. Natl. Inst. Anim. Health, 37: 643–649.
Omran, H.H. and Abd El-Azeim, A.M. (2000): Studies on some hematological and serum biochemical changes in blood of sheep naturally infected with piroplasmosis in Sharkia Governorate. J. Vet. Med. Res. Vol. џ, No. ∏. 25–36.
Pugh, D.G. (2002): "Sheep and Goat  Medicine" 1st ed. W.B. Saunder Company. p 149-153.
Radwan, M.E. and Ali, A.A. (2004): Clinical and biochemical studies in sheep naturally infected with babesia in Assiut Governorate. Beni-Suef Vet. Med. J. Vol. XIV NO. (1) 7: 21-28.
Ramadan, M.Y. and Lubna, M.A. (2000): Studies on sheep Babesiosis in Kalubyia Governorate, Egypt. Minufia Vet. J. Vol. 1 No. 14: 147–155.