STUDY ON SOME BACTERIAL CAUSES OF RESPIRATORY, ALIMENTARY AND MORTALITY DISEASES IN NEONATE LAMBS

Document Type : Research article

Authors

1 Dep. of Bacteriology, Animal Health Research Institute, Mansoura Laboratory.

2 Dep. of Bacteriology, Animal Health Research Institute, Zagazig Laboratory

Abstract

The present study was aimed to investigate the bacterial causes of newly born lamb mortalities. Seventy samples were collected (20 apparently healthy, 40 diseased and 10 dead lambs) their age ranged from one day up to 3 months old. The clinical symptoms of diseased lambs were weakness, partial loss of appetite, diarrhoea and respiratory signs. The bacteriological examination revealed that 48 samples (68.6%) were positive for bacterial isolation and 30 (62.5%) and 18 (37.5%) were single and mixed infection respectively. E. coli was isolated at incidence percentage 23(31.9%), Pasturella spp. 16(22.2%), Salmonella spp. 13 (18.1%), Klebsiella spp. 8(11.1%), Staphylococcus aureus 6(8.3%), Streptococcus spp. 4(5.6%) and Pseudomonas spp. 2(2.8%). E.coli isolates were identified serologically into 5 (O26), 7 (O55), 4 (O101) and 7 untyped strains. Also, ٍٍSalmonella spp. was identified as 6                      S. typhimurium, 4 S. montividio and 3 untyped strains. In vitro sensitivity test of isolated strains revealed that the most effective antibiotic were sensitive for Enrofloxacin, Cefotaxim and Trimethoprim sulfameth-axazole and should be used in treatment of diseased cases.

Keywords


Dep. of Bacteriology,

Animal Health Research Institute, Mansoura Laboratory.

                      

Study on some bacterial causes of respiratory, Alimentary and mortality diseases in neonate lambs

(With 4 Tables)

 

By

M.M. Abd-El-Latif; A.H. Moustafa; M.K. Rezik and M.A.S. Moustafa*

* Dep. of Bacteriology, Animal Health Research Institute,

Zagazig Laboratory.

(Received at 5/4/2009)

 

دراسة عن بعض المسببات البکتيرية للأمراض التنفسية والهضمية والنفوق في الحملان حديثه الولادة

 

محمود محمد محمود عبد اللطيف ، عادل حسانين محمود مصطفى ،

مدحت کمال رزق ، محمدعلى صالح مصطفى

 

أجريت هذه الدراسة لمعرفة بعض المسببات البکتيرية المصاحبة للنفوق المبکر فى الحملان حديثة الولادة. من خلال تلک الدراسة تم جمع 70 عينة من الحملان (السليمة ظاهريا والمريضة والنافقة حديثا) من عمر يوم حتى 3 شهور فى إحدى المزارع الخاصة بمحافظه الدقهلية. وقد أظهر الفحص الإکلينيکي فقدان الشهية وضعف عام وإسهال بالاضافه إلى اضطرابات تنفسية على الحملان المريضة. وتم فحص العينات بکتيريولوجيا وذلک بزرعها على أوساط غذائية مختلفة. وأظهرت نتائج الفحص البکتريولوجي وجود 48 (68.6%) حالة إيجابية للعزل البکتيري حيث تبين إصابة بعض الحالات 30(62.5%) عدوى فردية بينما 18 (37.5%) عدوى مختلطة. وقد تم عزل کل من الميکروب القولوني 23(31.9%) , باستريلا 16(22.2%), سالمونيلا 13(18.1%)، کليبسيلا 8(11.1%), الميکروب العنقودي الذهبي 6(8.3%), مکورات سبحية 4( 5.6 %) وسيدوموناس 2(2.8%). وقد تم تصنيف معزولات الميکروب القولوني سيرولوجيا إلى 5 عترات (O26), 7 (O55),      4 (O101) و7 عترات غير مصنفة وکذلک معزولات السالمونيلا إلى 6 عترات سالمونيلا تيفيموريم و4 عترات سالمونيلا مونتيفيديو و3 عترات غير مصنفة. کما تم عمل اختبار الحساسية للميکروبات المعزولة السائدة حيث کانت معظم المعزولات حساسة لکل من الإنروفلوکساسين والسيفوتاکسيم والسلفاميثوکسازول تراى ميثوبريم. وقد تم مناقشة النتائج والتوصيات الواجب إتباعها لتجنب الإصابة بهذه الميکروبات وللمحافظة على الحالة الصحية للحملان.

 

Summary

 

The present study was aimed to investigate the bacterial causes of newly born lamb mortalities. Seventy samples were collected (20 apparently healthy, 40 diseased and 10 dead lambs) their age ranged from one day up to 3 months old. The clinical symptoms of diseased lambs were weakness, partial loss of appetite, diarrhoea and respiratory signs. The bacteriological examination revealed that 48 samples (68.6%) were positive for bacterial isolation and 30 (62.5%) and 18 (37.5%) were single and mixed infection respectively. E. coli was isolated at incidence percentage 23(31.9%), Pasturella spp. 16(22.2%), Salmonella spp. 13 (18.1%), Klebsiella spp. 8(11.1%), Staphylococcus aureus 6(8.3%), Streptococcus spp. 4(5.6%) and Pseudomonas spp. 2(2.8%). E.coli isolates were identified serologically into 5 (O26), 7 (O55), 4 (O101) and 7 untyped strains. Also, ٍٍSalmonella spp. was identified as 6                      S. typhimurium, 4 S. montividio and 3 untyped strains. In vitro sensitivity test of isolated strains revealed that the most effective antibiotic were sensitive for Enrofloxacin, Cefotaxim and Trimethoprim sulfameth-axazole and should be used in treatment of diseased cases.

 

Key words:Lambs, mortality, respiratory, disorders, enteritis

 

Introduction

 

Early mortality of lambs is a major constraint on total sheep productivity. This problem is not a simple one, as it is not related to a specific cause but is the result of many factors attributable to climatic conditions, environmental stress, genetic influences, nutritional and infection causes (Nash et al., 1996).     

The major causes of death in lambs were pneumonia, digestive problems (Diarrhoea), endoparasitic infestations, starvation and septicemia(Mukasa- Mugerwel et al., 2000). Bekele et al. (1992) and Abdel hadi et al. (2006) they observed that pneumonia and enteritis were from the commonest causes of high proportional morbidity and mortality rates between the lambs (Mishra et al., 2000).

Respiratory disorders caused by bacterial infections were considered as leading cause of lamb death among grazing sheep(Rowland et al., 1992; Haziroglu et al., 1994 and Martin 1996). Diarrhoea is still the most common and costly disease affecting neonatal small ruminants (Pugh, 2002 and Andres et al., 2009).

Many organisms were incriminated as causative agents of diarrhoea and death in newly born lambs after natural and experimental infections (Karmy and Ragab, 1983 and Munoz et al., 1996). The most important bacterial causes of pneumonia and and diarrhoea are E. coli,  Salmonella spp., Pasteurella spp.,Klebsiella spp., Staphylococcus,  Streptococcus and Pseudomonas spp. (Nesterov, 1981, Shegidevich      et al., 1983, Leondidis et al., 1983 and Sharif et al., 2005). These pathogens are responsible for great mortality and various morbidity changes and atthesame time contribute a hazard to public health(Orden et al., 2000 and Sharif et al., 2005).  

The aim of this work is to isolate and identify some bacterial causes which recovered from both pneumonic, enteric cases and dead lambs. Determination of invitro antibiotic sensitivity of isolated organisms was also aimed.

 

Materials and Methods

 

1- Animals:

            A total number of 70 samples newly born lambs (20 clinically healthy, 40 diseased and 10 dead lambs) from birth up to 3 months old of both sexes were located at a private farms in Dakahlia Governorate and subjected for clinical and laboratory investigations (Kelly, 1984).

2- Samples:

            Samples from nasal and rectal swabs were collected from all cases. Other samples from liver, heart, lung, spleen, lymph nodes and small intestine were taken from dead ones under a septic conditions and sent without delay to the laboratory for bacteriological examination.

3- Bacteriological examination:-

The obtained samples were inoculated by sterile platinum loop in Nutrient, MacConkey and Selnite "F" broth and incubated at 37ºC for 18 hr. and then subcultured into Nutrient agar, 5% Blood sheep agar, S.S agar and MacConkey agar plates, then incubated over night at 37 ºC. The produced colonies were prepared and stained with Gram stain, then examined microscopically for detection of morphological appearance, arrangement and staining reactions of the isolates (Cruickshank et al., 1982). Isolates thenafter were identified by biochemical tests (Edwards and Ewing 1972, Koneman et al., 1997 and Qunin et al., 2002).

 

 

 

4- Serological identification of E.coli and Salmonella:

a- E.coli: Serological identification of purified E.coli strains using available agglutinating Coli test sera (Behring merk, AG Marburg) was done according to manufacturer's instruction ( Lab , Germany).

b- Salmonella: The biochemically identified Salmonella strains were subjected for serological identification as described by Edwards and Ewing (1972), and the instruction of the manufacturer (Denken Selken Co. LTD, Tokyo, Japan).

5- Invitro antibiotic sensitivity test: The disc diffusion technique was performed on the isolated bacteria using Muller-Hinton (Oxoid 1998).

Ten chemotherapeutic discs were kindly supplied by Oxoid and namely: Enrofloxacin, Amoxycillin, Ampicillin, Gentamycin, Strepomycin, Cefotaxim, Erythromycin, Colistin sulphate, Oxytetracycline and Trimethoprime sulphamethexazole.

 

RESULTS

 

Clinical signs: The main clinical signs encountered for diseased lambs were depression, off food, emaciation and diarrhoea (either mucoid or bloody). In some cases difficult breathing, sneezing and nasal discharge.

Postmortem lesion: Dead lambs showed the following lesions: congestion of small and large intestines, congestion liver, kidneys and mesenteric lymph nods. In some cases there was congested lungs.

The results of bacteriological examination were recorded in Table 1, 2, 3 and 4.

 

Table 1: Results of bacteriological examination of obtained samples

 

Source of samples

Total No. of examined samples

Positive samples

Single isolates

Mixed isolates

Total No. of isolates

No

%

No

%

No

%

 

 

1-Apparently  

    healthy lambs

2-Diseased lambs

 

3- Dead  lambs

20

 

40

 

10

  6

 

32

 

10

  30.0

 

  80.0

 

100.0

  4

 

22

 

 4

66.7

 

68.8

 

40.0

 2

 

10

 

 6

33.3

 

31.2

 

60.0

 

 6

 

46

 

20

 

     Total

70

48

 68.6

30

62.5

18

37.5

72

 

 

 

Table2: Types of pathogenic bacteria recovered from examined samples

 

Bacterial isolates

Condition of lambs

Total

Apparently healthy lambs (20*)

Diseased lambs

(40*)

Dead

lambs

(10*)

No.

%

No.

%

No

%

No.

%

E. coli

Salmonella spp.

Pasteurella spp.

Klebsiella spp.

Staph.aureus

Streptococcus

Pseudomonas spp.

2

0

2

0

1

1

0

10.0

  0.0

10.0

  0.0

  5.0

  5.0

  0.0

14

  8

11

  6

  3

  2

  2

35.0

20.0

27.5

15.0

 7.5

 5.0

 5.0

7

5

3

2

2

1

0

70.0

50.0

30.0

20.0

20.0

10.0

00.0

23

13

16

  8

  6

 4

 2

31.9

18.1

22.2

11.1

 8.3

 5.6

 2.8

 

6

 

  46

 

 20

 

 72

100.0

 

* No. of examined samples.

 

Table 3: Serological identification of isolated E. coli and Salmonella strains.

 

Source of

Samples

(23) E. coli

(13) Salmonella

O26

O55

O101

Untyped

Total

S.

typhimurium

S.

montividio

untyped

Total

No.

%

No.

%

No.

%

No.

%

 

No.

%

No.

%

N0.

%

 

App. Healthy   lambs

1

4.3

0

0.0

0

0.0

1

4.3

2

0

0.0

0

0.0

0

0.0

0

Diseased lambs

2

8.7

5

21.7

3

13.1

4

17.4

14

2

15.4

2

15.4

1

7.7

5

Dead lambs

2

8.7

2

8.7

1

4.3

2

8.7

7

4

30.7

2

15.4

2

15.4

8

Total

5

21.7

7

30.4

4

17.4

7

30.4

23

6

46.1

4

30.8

3

23.1

13

 

 

Table 4: Invitro antibiotic susceptibility of important isolated bacteria

 

           Organisms

 

 Antibiotic agent 

E. coli

Salmonella

 

Pasteurlla

Klebsilla

Staph.

aureus

 Enrofloxacin        5  ug

 Amoxycillin        25 ug

 Ampicillin          10 ug

 Gentamycin        10 ug

 Streptomycin      10 ug

 Cefotaxim           30 ug

 Erythromycin     15 ug

 Colistin sulphate 10ug

 Oxytetracyclin    30 ug

 Trimethoprim-sulpha methaxazole 1.25-23.75ug

+++

R

R

++

++

+++

R

++

++

+++

+++

R

R

++

++

+++

R

++

++

+++

 

++

R

R

R

++

+++

R

R

++

++

+++

R

R

+++

++

+++

R

++

R

++

 

+++

R

R

++

++

+++

R

++

++

+++

 +++ = Highly sensitive

 ++   = Moderately sensitive

  R     = Resistante

 

Discussion

 

Neonatal lamb mortality represents an economic loss and welfare concern. Mortality in lambs can be provoked by a multitude of both infections and non infectious causes. A varieties of infectious pathogens were revealed from diseased and dead lambs mainly bacterial causes. (Mitchell and Link Later, 1983).

The bacteriological examination of 70 samples from lambs revealed 48 (68.6%)  positive bacterial infection, where 6 (30.0%) from apparently healthy lambs, 32(80.0%) from diseased lambs and 10(100%)from dead lambs Table (1).

On the other hand, Ibrahim and Selim (2003) isolated the pathogenic bacteria from apparently healthy, diseased and dead lambs with percentage of 20 %, 66.7% and 78.3% respectively. Khadr et al. (2006) isolated Campylobacter spp. with percentage of 12.3% from diseased lambs and 7.5% from apparently healthy lambs. Also Hala and Amany (2007) isolated Salmonella spp. from healthy and diseased lambs with percentage 4.7% and 12.7% respectively. Concerning the results in table (2) for the incidence of pathogenic bacteria in examined lambs results indicated that E.coli 23 (31.9%), Pasteurella spp. 16 (22.2%), Salmoenlla spp 13(18.1%), Klebsiella spp. 8 (11.1%), Staphylococcus aureus 6 (8.3%), Streptococcus spp. 4 (5.6%) and Pseudomonas spp. 2 (2.8%). It appears that the most prevalent bacteria were E. coli, Pasteurella spp., Salmonella spp.

This agreed with results reported by Sharif et al. (2005) who recorded that the bacteria responsible for neonatal mortality were E.coli, Pasteurella and Staph. aureus, also E. coli was the most frequent bacteria  identified as a cause of neonatal mortality in lambs.

Results in Table (3) revealed that E. coli serotypes identified as 5 (21.7%) O26, 7 (30.4%) O55, 4 (17.4%) O101 and 7 (30. 4%) untybed strains. This result seems in accordance with those reported byRao and Char, (1983) who isolated E. coli serotypes O26 and O55 from pneumonic lung of septicemic lambs, Duff and Hunt (1989) also isolated E.coli strain O101 from 4 day old dead lambs. Salmonellosis is a very important disease of lambs causing enteritis and septicemia, Salmonella is potentially lethal to lambs (Moredun Foundation, 2007). Also it is constitute a hazard to public health as all serovares can produce diseases to human (WHO, 2006). The results given in Table (3) revealed that 13 Salmonella strains recovered from examined samples were serotyped as:  6 (46.1% ) S.typhimurium as the most one, 4 (30.8%) S.montividio and 3 (23.1%) untyped strains. This resultis similar with those of Hala and amany (2007) who recorded that S.typhimurium was the most predominant isolate from dead lambs. On other hand Soumaya and Fadel (2004) isolated S.dublin and S. enteridis from dead lambs. The data presented in Table (4) showed that most isolates were highly sensitive to Enrofloxacin, Cefotaxim and Trimethoprim sulphamethaxazole and resistance to Ampicillin, Amoxycillin and Erythromycin.

Hatem et al. (2003) mentioned that the bacterial isolates from diseased sheep and goats were sensitive to Ciproflaxocin, Danofloxacin and Enrofloxacin and resistance to Ampicillin,Gentamycin and Trimethoprim -sulphamethaxazole.

           Finally we could conclude that the most mortality rate between the newly born lambs due to pneumonia and diarrhoea. Also the most prevalent bacterial isolates are E.coli, Salmonella and Pasteurlla spp. So adequate hygienic measures and proper management may reduce the degree of animals exposure to disease producing agents.

 

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Abdel Hadi, S.A.; Niar, A.; Abdelhadi, F.Z.; Smail, N.L. and Ouzrout, R. (2006): Perinatal lamb mortalities on the level of Tiaret area (Algeria). Assiut Vet. Med. J. 52(109): 191-197.
Andres, S.; Jimenez, A.; Sanchez, J.; Alonso, J.; Gomez, L.; Lopez, F. and Rey, J. (2009): Evaluation of some etiological factors              predisposing to diarrhoea in lambs in La Serna (Southwest              Spain). Small Ruminant Research, 70, (2), 272-275.
Bekele, T.; Kasali, O.B. and Woldeab, T. (1992): Causes of lamb               morbidity and mortality in the Ethiopian highlands. Vet. Res. Commun.16 (6): 415-24.
Cruickshank, R.; Duguid, J.P.; Marmoni, B.P. and Swain, R.H. (1982): Medical Microbiology. 12th Ed. Churonill Livingestone Edinburg, London, UK.
Duff, J.P. and Hunt, B.W. (1989): Lamb die from porcine E.coli.              Vet. Rec. 125(15): PP. 404.
Edwards, P.R. and Ewing, W.H. (1972): Identificationof Enteroba-cteriacae, 3rd edition. Burgeon Publishing Company, Atlanta, USA. P 103-104.
Hala, S. Ibrahim and Amany, H. El-Gohary (2007): Prevalence of              Salmonella in sheep and its environment with reference to              detection of virulence associated gene using PCR. Vet. Med. J. Giza. 55 (4): 1035-1051.
Hatem, M.E.; Mona, S.; Zaki Osman, A.H. and Mona El-Shabrawy (2003): Bacteriological, Histopathological and clinicopathological studies on respiratory affection in sheep and goats in Egypt. J. Egypt. Vet. Med. Assoc., 63(1): 97-109.
Haziroglu, R.; Diker, K.S.; Gulbahar, M.Y.; Akan, M. and Guvenc, T. (1994): Studies of the pathology and microbiology of pneumonic lungs of lambs. Dtsch Tierarztl Wochenschr.           101(11): 441-3.
Ibrahim, E.M. and Selim, A.M. (2003): Pathological and bacteriological studies on an outbreak of pneumonia pasteurellosis in sheep at Sharkia Province. Egypt. J. Agric. Res., 81(1): 33-49.
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