Livestock Research for Rural Development 29 (1) 2017 Guide for preparation of papers LRRD Newsletter

Citation of this paper

Major gastrointestinal nematodes of cattle in dairy farms in Dire Dawa administration, eastern Ethiopia

Jelalu Kemal, Yimer Muktar and Adem Hiko

Haramaya University, College of Veterinary Medicine, P. O. Box 138, DireDawa, Ethiopia
jelaluk@gmail.com

Abstract

Gastrointestinal nematode infections are among the major health problems limiting the productivity in dairy cattle. A cross sectional study was conducted from October 2014 to May 2015, to estimate the prevalence and identify the major genera of nematodes in dairy cattle farms in Dire Dawa Administration, eastern Ethiopia. A total of 384 fecal samples from dairy cattle were collected and examined for nematode infection using standard coprological methods. Out of these, 203 (52.9%) animals were found positive for one or mixed nematode infection. Specifically, Trichostrongylus (20.1%), Strongyliods (16.1%), Oesophagostomum (13.3%), Haemonchus (10.9%), Dictyocaulus (9.4%) and Trichuris (4.9%) were the identified genera in descending order of prevalence. The proportion of mixed infection was 97 (25.26%).The highest percentage was recorded with Trichostrongylus and Dictyocaulus 13(13.4%). Among the potential associated risk factors, history of de-worming (p=0.00) and body condition (p=0.02) were found significantly associated with the occurrence of nematode infection. Source of animals, age and breed of the animals revealed no significant relation with prevalence of nematodes. The degree of infection revealed that majority (50.74%) of the examined animals were moderately infected with nematode parasite. Therefore, strategic de-worming should be practiced in the dairy farms.

Key words: coproculture, cross sectional, parasite, prevalence


Introduction

Ethiopia has Africa's largest livestock record with an estimated total cattle population of about 57.83 million (CSA 2015). Livestock are raised together with crop cultivation in the high land areas of the country whereas in the low land or the pastoral areas, subsistence is based mainly on livestock and livestock products (CACC 2003). Recently, large and considerable number of small-scale urban dairy farming using crossbreed cattle is emerging as an important business enterprise in many regional towns of the country. Milk produced from these dairy farms provides an important source of family nutrition for the majority of urban population in the country (Hailu 2011). Furthermore, cattle also serve as a means of risk diversion and accumulation of wealth among the rural community (Yohannes 2002).

However, diseases have numerous negative impacts on productivity and fertility of herds (Elsa et al 2012). The gastrointestinal tract (GIT) of animals harbor a wide variety of parasites mainly helminthes, which cause clinical and sub clinical parasitism. These parasites adversely affect the health status of animals and cause enormous economic losses to the livestock industry (Irfan 1984; Tesfaye 2009).

Helminthes infection, especially subclinical gastrointestinal nematode infections are among the major health problems limiting the productivity in dairy animals (Dimander et al 2000). Nematodes cause losses through reduction in food intake and reduced weight gain, reduced work capacity, lower milk production, and mortality in heavily parasitized animals (Mcleod 1995). Some of the major nematodes accountable for GIT parasite infection in livestock under tropical environment include: Trichostrongylus, Haemonchus, Nematodirus, Cooperia spp., Trichuris, Oesophagostomum spp., Dictyocaulus and Strongyloides spp. (Troncy 1989). High prevalence of GIT parasites in dairy cows have been reported in Africa including Ethiopia. Although several studies regarding ruminant helminthosis were undergone in Ethiopia including by Adem and Anteneh(2011), Hailu et al (2011) and Zerihun (2012), only limited effort was made to study nematode infection in dairy farms. Therefore, it is imperative to investigate the current status of nematode infection along the assumed factors and to identify the major genera of nematodes in the study area.


Materials and methods

Study Area Description

The study was conducted in Dire Dawa, eastern Ethiopia which is located at about 515 km from Addis Ababa, the capital of Ethiopia. The area is located between 9°27' and 9°49' N latitude and 41°38' and 42°19' E longitude (Figure 1). The total area of the administration is 128,802 km2 ha and it shares common boundaries with Oromia Regional State to the south and Somali Regional State to the west, north, and eastern part. Administratively, it is divided into 9 urban kebeles (lower administrative unit) and 32 peasant associations. The rural area occupies 98.7% of the total area. The altitude of Dire Dawa Administration (DDA) ranges from 960 m.a.s.l in the northeast to 2450 m.a.s.l. in the southwest. The mean annual rainfall of the area varies from 550 mm in the lowland northern part to 850 mm in the southern mountain with average 640 mm. The rain fall pattern of the area is characterized by short rainy season from February to May and big rainy season from July to September. The dry season extends from October to January. The monthly mean minimum and maximum temperature ranges from 14.5 °C to 34.6 °C respectively. Using the 1500 m contour as a line of separation, two agroecological zones, the kola (below 1500 m) and Woina Dega (above 1500 m) have been recognized. The natural vegetation consists of dispersed patches of degraded drought-resistant grasses, bushes and shrubs. Out of the rural population about 4% are pure pastoralists and they are engaged in livestock production. The total livestock population in DDA is estimated to be 219,323. Goats comprise the highest proportion (54.2%) followed by sheep (21.1%) and cattle (18.4%) (CSA 2007).

Figure 1. Map of Dire Dawa administration.
Sample size determination

The study farms were selected purposively according to farm owners willingness, accessibility and cattle population among the major fifteen dairy farms. A prevalence of 50% was taken into consideration for sample size determination since there was no any previous research conducted specifically on nematode infection in the area. The desired sample size for the study was calculated using the formula given by Thrusfield (2005) with 95% confidence level (CI) and 5% desired absolute precision. Accordingly, 384 Cattle were considered in the study while allocation of this sample to the respective farm was undergone proportionally based on the size of the farms.

Study design and population

Across sectional type of study was conducted from October 2014 to May 2015 to estimate the prevalence of nematode parasitism and identify the major genera of nematodesin dairy farms in the study area. During the study, 384 dairy cattle were examined including 200 local, 84 exotic and 100 cross breeds. The management of the farms was categorized as described by Ameni et al. (2003) on the basis of housing condition (neatness, waste disposal, nature of the floor, presence of confinement), feeding, possession of an exercise yard, and contact with other herds and provision with clean water. Intensive, extensive and semi-intensive types of dairy cattle production systems have been practiced. Dairy cattle production using improved breeds is a common practice in urban and peri-urban areas. Feeding method is supplemented with natural grass hay, crop residues such as straws and chaffs of cereals and pulps, silage, and agro industrial by-products mostly from the flour/oil industries and brewery residues. Dairy producers who keep improved dairy cows also cultivate improved forage crops such as elephant grass, oats, vetch and alfalfa to supplement grazing.

Study methodology

A list of farms owning dairy cattle were obtained from Agricultural Offices and these farms were used as sampling frames. Using a two-stage cluster sampling method farms and individual animals were considered as primary and secondary units, respectively. Cattle from each of the study farms were categorized into adults (over 3 years old), young (1–3 years old) and calves (less than one year old) according to Frandson (1992). Examined animals were also categorized into three body condition groups involving poor, medium and good body condition based on the description of Nicolson and Butterworth (1986). Poor body condition cattle were having prominent dorsal spines pointed to the touch and individual visible transverse processes. Cattle having usually visible ribs with little fat cover and barely visible dorsal spines were considered as medium body condition score. A good body condition score was given for cattle when fat cover easily seen in critical areas and the transverse processes were not felt. At the time of sample collection all relevant information about sex, age, breed, body conditions and de-worming history of the study animals were registered.

Sample collection and processing

The fecal samples were collected per rectum and placed in sample collecting bottles, labeled and transported to the Dire Dawa Regional veterinary parasitology laboratory and then the standard flotation techniques was applied to screen for the nematode eggs. For positive fecal sample, modified McMaster egg counting technique was used to identify the degree of infection by estimating eggs number per gram of feces based on the previous work of MAFF (1986). The levels for nematode infection were extrapolated from severity index defined by FAO (2009), where cattle are proposed to have low, moderate and severe nematode infections, if their fecal egg counts are less than 100 to 250, from 250 to 500 and greater than 500 per gram of feces, respectively.

Furthermore, coproculture of fecal samples was employed and the larvae were identified to genus level. The coproculture procedure applied in the study was started by preparing fecal samples and then the fecal samples were finely broken up by using stirring device after moistening it with water. Then it was transferred to an incubator having a temperature of 37oC for 10 days. During these days water was added every 2 days to the culture. Finally the third stage larvae (L3) and/or when present L2 larvae were collected by Baermann technique and differentiated according to MAFF (1986). The larvae were counted and subjected to morphological examination for identification of the genera as Described by Hansen and Perry (1994).

Data analysis

The data containing the response and explanatory variables were classified, filtered, coded and entered in to Ms-Excel spread sheet 2007. Then it was transferred to SPSS version 20 for statistical analysis. Chi square (χ2) was employed to indicate the association between different assumed factors and occurrence of nematode in addition to descriptive statistic including frequency and percentage. Statistically relations were reported as significant, if p-value is less than 5 % (p<0.05).


Results

In the current study, from the total 384 cattle examined, 52.9% (n=203) were positive for nematode infection. Source, age and breed of the animals did not revealed any significant (p>0.05) relation with occurrence of nematodes.However, the prevalence of nematodes revealed significant association with body condition score and history of de-worming the cattle. Poor body condition animals (64.1%) had significantly (p=0.02) higher prevalence than medium (53.9%) and good body condition animals (45.3%). Similarly, animals with de-worming history (46.1%) had significantly (p=0.00) low risk of exposure than the untreated animals (64.5%) (Table 1).

Table 1. Prevalence of gastrointestinal nematodes infection with risk factors

Risk factors

Total number
examined

Positive
number (%)

χ2

p

Source

    Farm A

84

45(53.6)

0.59

0.89

    Farm B

156

80(51.3)

    Farm C

93

52(55.9)

    Farm D

51

26(51.0)

Breed

    Local

200

98(49.0)

3.25

0.19

    Cross

100

60(60.0)

    Exotic

84

45(53.6)

Age

    Calve

84

52(61.9)

3.6

0.18

    Young

121

62(51.2)

    Adult

179

89(49.7)

Body condition

    Poor

78

50(64.1)

7.2

0.02*

    Medium

169

91(53.9)

    Good

137

62(45.3)

De-worming status

    Dewormed

243

112(46.1)

12.2

0.00*

    Undewormed

141

91(64.5 )

*Statistically significant

The fecal culture result indicated Trichostrongylus, Strongyloides, Oesophagostomum as the most dominant nematodes with respective prevalence of 20.1%, 16.2% and 13.3%, respectively. On the other hands, Haemonchus (10.9 %,), Dictyocaulus (9.4% ) and Trichuris (4.9% ) occurred however at a low prevalence (Table 2).

Table 2. Distribution of different genera of GIT nematodes with different risk factors

Risk factors

No.
examined

Trichostrongylus
No. (%)

Strongyloides
No. (%)

Oesophagost
Omum
No. (%)

Haemonchs
No. (%)

Dictyocaulus
No. (%)

Trichuris
No. (%)

Source

    Farm A

84

18(21.4)

14(16.7)

11(13.10)

10 (11.9)

9(10.71)

4(4.76)

    Farm B

156

31(19.9)

26(16.7)

19(12.18)

17(10.9)

12(7.69)

9(5.77)

    Farm C

93

18(19.4)

16(17.2)

13(13.98)

11(11.83)

10(10.8)

4(4.3)

    Farm D

51

10(19.6)

6(11.8)

8(15.70)

4 (7.80)

5(9.8)

2(3.9)

Breed

    Local

200

40(20.0)

25(12.5)

27(13.5)

15(7.5)

16(8.0)

10(5.0)

    Cross

100

19(19.0)

23(23.0)

13(13.0)

17(17.0)

11(11.0)

5(5.0)

    Exotic

84

18(21.4)

14(16.7)

11(13.1)

10(11.9)

9(10.7)

4(4.8)

Age

    Calve

84

18(21.4)

16(19.1)

9(10.7)

12(14.3)

9(10.7)

5(5.9)

    Young

121

26(21.5)

16(13.2)

16(13.2)

9(7.4)

12(9.9)

2(1.7)

    Adult

179

33(18.4)

30(16.8)

26(14.5)

21(11.7)

15(8.4)

12(6.7)

Body condition

    Poor

78

23(29.5)

11(14.1)

12(15.3)

6(7.7)

9(11.5)

2(2.6)

    Medium

169

32(18.9)

31(18.3)

24(14.2)

24(14.2)

12(7.1)

9(5.3)

    Good

137

22(16.1)

20(14.7)

15(10.9)

12(8.8)

15(10.9)

8(5.8)

De-worming status

    De-wormed

243

42(17.3)

34(13.9)

30(12.4)

23(9.5)

24(9.88)

10(4.1)

    Undewormed

141

35(24.8)

28(19.9)

21(14.9)

19(13.5)

12(8.5)

9(6.4)

Total examined

384

77(20.1)

62(16.2)

51(13.3)

42(10.9)

36(9.4)

19(4.9)

From the total 203 (52.9%) prevalence, 106 (27.6%) samples were infected with single infection while 97 (25.26%) were found to be infected with mixed infection. The highest paired infection 13(13.4%) observed was Trichostrongylus and Dictyocaulus followed by Strongylus andHaemonchus 10(10.3%) while the lowest mixed infection was Haemonchus and Dictyocaulus(1.03%) and Haemonchus andTrichuris(1.03%). In addition, there was one triple infection which was observed in a combined infection of Strongyloides, Haemonchus and Dictyocaulus (1.03%) (Table 3).

Table 3. Proportion of single and mixed infection with different GIT nematodes

Types of nematode infection

Frequency

Proportion

Single infection

Trichostrongylus

44

41.50%

Strongyloid

27

25.47%

Oesophagostomum

15

14.15%

Haemonchus

14

13.20%

Dictyocaulus

4

3.77%

Tricuris

2

1.88%

Sub total

106 (27.6%)

100%

Mixed infection

Trichostrongylus and Strongyloid

4

4.12%

Tricostrongylus and Oesophagostomum

8

8.25%

Trichostrongylus and Haemonchus

6

6.2%

Trivhostrongylus and Dictyocaulus

13

13.4%

Trichostrongylus and Trichuris

5

5.15%

Strongylus and Oesophagostomum

9

9.27%

Strongylus and Haemonchus

10

10.3%

Strongyloid and Dictyocaulus

6

6.18%

Strongyloid and Trichostrongylus

7

7.22%

Oesophagostomum and Haemonchus

9

9.27%

Oesophagostomum and Dictyocaulus

8

8.25%

Oesophgostomum and Trichostrongylus

6

6.2%

Haemonchus and Dictyocaulus

1

1.03%

Haemonchus and Tricuris

1

1.03%

Dictyocaulus and Trichostrongylus

3

3.1%

Strongyloid, Haemonchus and Dictyocaulus

1

1.03%

Sub total

97 (25.26%)

100%

Grand total

203 (52.9%)

Concerning with degree of infection intensity of nematodes, the dominant proportion of the study animals were infected with moderate infection (50.74%), while low and severe infection level was recorded from 33.5% and 15.76% of the animals, respectively (Table 4).

Tabla 4. Burden of nematode infection in dairy cattle of the study area

Infection rate

No. positive

Prevalence (%)

Low

68

33.50

Moderate

103

50.74

Severe

32

15.76

Total

203

100


Discussion

The study indicated a high prevalence of gastrointestinal nematodes. Overall 52.9% of dairy animals examined were positive for GIT nematodes. This finding was comparable with previous report of Adem and Anteneh (2011), Addisu and Berihu (2015) and Regassa et al (2006) who reported 54%, 49% and 50.2`% prevalence from different parts of Ethiopia, respectively. The agreement in nematode finding level might be due to similar agro-ecological setting, management and designs of the studies. However, the present finding was higher than the previous report (27.57%) by Tigistet al (2012) in the Northern part of the country. furthermore , Degefu (2011) and Etsehiwot (2004) reported 42.3% in Jimma town and 82.2% prevalence in central Ethiopia, respectively whereas in Tanzania, Keyyu et al (2006) recorded prevalence of 44.4% GIT parasites in dairy cattle. The variations among reports might be prevalence of GIT helminthes varies considerably depending on local environmental condition such as humidity, temperature, rainfall, vegetation and management practice (Gizachew 2007

On the other hands, it was much lower than 97.2% prevalence report in dairy animals from Tanzania (Keyyu et al 2003). This discrepancy was probably due to difference in ecology, health care practice, feeding pattern and management system in general.

In the present study, there was significantly higher prevalence of nematodes in poor body condition cattle (64.1%) than in medium (53.9. %) and good body condition animals (45.36%). This concurred with previous reports by Addisu and Berihu (2015) who reported significantly higher prevalence of GIT parasite in poor body condition animal (62.7%) than in the medium (55.7%) and good body condition (37.2%) cattle. Likewise, Tigist et al (2012) reported considerably higher prevalence in poor body condition cattle (65.1%) than in medium (26.3%) and good body condition animal (13.6%). This relationship could be explained not only by exacerbation of parasitic infection in poor body condition animals due to lowered immunity but also by the fact that loss of body condition in this group of animal could be due to nematode infection.

De-worming of cattle had a significant (p =0.00) association with the occurrence of nematodes in which dewormed animals had lower rate (46.1%) of nematodes infection as compared to non-dewormed cattle (64.5 %). Likewise, study by Addisu and Berihu (2015) which showed significant association ( p=0.00) between de-wormed (41.3%) and not de-wormed animals (71.9%). These might be due to the obvious preventive effect of strategic anti-helminthes application.

Among the sources farms of the diary animals, there was no significant association with prevalence of the nematode infection in the current study. This might be due to the same ecological condition. Similarly, breed of the animal did not show significant association with the prevalence of the parasites. However, Addisu and Berihu (2015) reported that exotic breed cattle (76.66%) were significantly more susceptible than the local (43.52%) and cross breed cattle (64.15%). This was probably attributed to the poor immune response of exotic breed to the hostile environment of tropical area including exposure to severe parasitic infection.

On the other hands, there was no significant difference was observed in the prevalence of nematodes among the age groups of the current study. This result was in line with Hailu et al (2011) who reported no significant difference between the calves and adult cattle. This could be due to equal exposure and the same management system for all age group under the same roof. However, there was significant difference between age groups according to the study by Tigistet al (2012) which could be attributed to different management system for different age groups.

In the present study, the most prevalent nematode genera in dairy cattle was Trichostrongylus (20.1%). This was lower than previous report of Adem and Anteneh (2011) with 37% and higher than the report of Addisu and Berihu (2015) and Shirale et al (2008) with respective prevalence of 3.65% and 3.14%. The second most prevalent genera of nematodes in this study were Strongyloids (16.2%) followed by Oesophagostomum (13.3%). Likewise, Adem and Anteneh (2011) found Oesophagostomum with 11% whereas Zerihun (2012) reported 17.45% Strongyloids. On the other hands, Belem et al (2001) reported higher prevalence of Oesophagostomumradiatum (42.6%) while Hailu et al (2011) reported lower prevalence of Strongyloids (3.3%) when it was compared to the present study finding (16.2%).

The prevalence of Haemonchus (10.9%) in the current study was close to prevalence indicated by Adem and Anteneh (2011) and Addisu and Berihu (2015) who reported 11.6% and 11.7%, respectively. This similarity of result could be due to similarity in agro climatic condition and management system. The current Haemonchus finding (10.9%) was higher than that reported by Shirale et al (2008) with 6.57%. The two least prevalent nematode genera in this study were Dictyocaulus (9.4%) and Trichuris (4.9%). Other studies like Adem and Anteneh (2011) and Shirale et al (2008) reported Trichuris 5.42% and Dictyocaulus 0.5 %, respectively. This variation could be due to climatic conditions for transmission of the parasites, farm management techniques including feeding, watering systems, host immune response to infection of GIT parasites and inadequate use of anthelmintics.

Regarding the intensity of nematode infection, the current study showed high percent of low (33.50 %) and moderate (50.74 %) infection and relatively lower severe (15.76%) infection. The reason for the majority of the animals showed low and moderate infection might be associated with the development of immunity causing lower worm fecundity in adult animals (Klooserman 1991; Ploeger 1994). The low infection intensity also indicated the low transmission and sub-clinical condition of nematode infection.


Conclusions

Nematodes are important health problems of cattle in the study area with an overallprevalence of 52.9%.The current finding confirmed that Trichostrongylus,Strongyloides, and Oesophagostomum were the most dominant nematodes. Mixed infection of different nematodes were also observed in the study dairy farms. Managements, particularly history of de-worming and body condition of the animals were found to be related to the occurrence of nematode infection in dairy cattle farms. Therefore, appropriate control and preventive measures using strategic de-worming would have paramount importance.


Acknowledgments

The authors would grateful technical staff members of Dire Dawa Regional laboratory veterinary parasitology team for their technical support. Dairy farm cattle owners would also be acknowledged for their cooperation in using cattle during the study period.


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Received 31 October 2016; Accepted 3 December 2016; Published 1 January 2017

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