A cross-sectional study was carried out from July 2011 to September 2013 to assess the seroprevalence and identify risk factors of
Toxoplasmosis is an economically important disease of livestock, causing abortion, stillbirth, fetal malformation, preterm deliveries, and neonatal death predominantly in sheep and goats infected by
Several reports have indicated a great variation on the seroprevalence of
The estimated domestic ruminant population of Ethiopia in millions is sheep (27.35), goats (28.16), cattle (55.03), and camels (1.10) [
The study was conducted in three selected districts of East Hararghe zone of Oromia region, Ethiopia. The districts were found at an altitude ranging from 950 to 2950 meters above sea level (masl). Accordingly, Gursum district is located at 9°7′–32°14′N latitude and 42°17′–42°38′E longitude with an altitude range of 1200–2950 masl; Babille district is located at 8°9′–9°23′N latitude and 41°16′–41°46′E longitude with an altitude ranging from 950 to 2000 masl; and Haramaya district is located at 9°9′–9°32′N latitude and 41°50′–42°05′E longitude with an altitude ranging from 1600 to 2140 masl. The districts are inhabited mainly by the “Oromo” tribe. Crop production and livestock rearing are the main economic activities in the rural areas, while small-scale trade is practiced in urban areas. Sorghum, maize, groundnut,
The study animals comprised indigenous sheep, goats, cattle, and camels kept under extensive grazing system. Districts were selected purposively depending on their accessibility. Within the districts, 38
The sample size was determined using a method recommended by Thrusfield [
A total of 1360 animal sera were collected and analyzed from July 2011 to September 2013. Approximately 5–10 ml of blood was drawn from the jugular vein using plain vacutainer tubes and kept overnight at room temperature to clot for serum separation. Aliquots of sera were obtained by centrifugation at 3000 revolutions per minute for 10 min and the sera were transported to the parasitology laboratory of College of Veterinary Medicine and Agriculture at Bishoftu (Debre Zeyit) in ice box and stored at −20°C until they were tested.
All sera were tested for anti-
100 verbally consented owners of domestic ruminants whose herds and flocks were involved in the survey were interviewed using a structured close-ended questionnaire. The gathered information included the demographic characteristics of the animals such as age, sex, breed, herd size, and physiological status of the animals and their husbandry including house types, feed storage facilities, grazing types, and water sources as well as cats holding and the presence of feral cats in the vicinity (variables obtained from literatures).
The data were analyzed using STATA version 11.0 for MA Windows (Stata Corp., College Station, USA). The data were categorized to make the analysis easy. Accordingly, sheep and goats were classified in two groups as ≤1 year and >1 year old, cattle into three groups as ≤1 year, >1–5 years, and >5 years old, and camels into two groups, ≤4 years and >4 years old. The flock/herd size for sheep, goats, and cattle was considered as small (<10 animals) or large (≥10 animals), while for camels it was considered as small (≤34 animals) or large (>34 animals). Type of housing with total confinement is categorized as pen for sheep and goats and barn for cattle, while it is classed as fence for those with access to the outside. Water source was classified as mixed (river, stream, pond, and well), pond, and pipe water (except camels). Species seroprevalence and the association of risk factors as independent categorical variable with
Out of 1360 sera of domestic ruminants tested, the presence of anti-
Seroprevalence of
Species | Animal level | Herd/flock level | ||||||
---|---|---|---|---|---|---|---|---|
| No. of positive | Percentage (%) | 95% CI | | No. of positive | Percentage (%) | 95% CI | |
Sheep | 332 | 112 | 33.73 | 28.66–39.10 | 102 | 62 | 60.78 | 50.62–70.31 |
Goats | 410 | 113 | 27.56 | 23.29–32.16 | 120 | 67 | 55.83 | 46.48–64.89 |
Cattle | 326 | 35 | 10.74 | 7.59–14.61 | 82 | 19 | 23.17 | 14.56–33.80 |
Camels | 292 | 42 | 14.38 | 10.57–18.94 | 47 | 25 | 53.19 | 38.08–67.89 |
| ||||||||
Total | 1360 | 302 | 22.2 | 20.02–24.51 | 351 | 173 | 49.29 | 43.94–54.65 |
In a univariable analysis, goats had high risk of
A multivariable logistic regression analysis showed that sex of the animal and water source were risk factors for increased seroprevalence. A higher risk of
Analysis of risk factors related to
Variables | Category | Number tested | Positive (%) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
---|---|---|---|---|---|---|
District | Haramaya | 95 | 25 (26.3) | 1.00 (ref.) | 1.00 (ref.) | |
Gursum | 143 | 44 (30.8) | 1.24 (0.70–2.22) | 0.69 (0.35–1.34) | 0.270 | |
Babille | 94 | 43 (45.7) | 2.36 (1.28–4.35) | 0.95 (0.46–1.94) | 0.881 | |
| ||||||
Environment | Rural | 253 | 58 (22.9) | 1.00 (ref.) | — | — |
Urban | 79 | 54 (68.4) | 7.26 (4.16–12.68) | — | — | |
| ||||||
Sex | Male | 68 | 11 (16.2) | 1.00 (ref.) | 1.00 (ref.) | — |
Female | 264 | 101 (38.3) | 3.21 (1.61–6.41) | 2.63 (1.18–5.88) | 0.019 | |
| ||||||
Age | ≤1 year | 39 | 9 (23.1) | 1.00 (ref.) | 1.00 (ref.) | |
>1 year | 293 | 103 (35.2) | 1.81 (0.83–3.95) | 1.15 (0.45–2.91) | 0.772 | |
| ||||||
Flock size | Small | 270 | 89 (33.0) | 1.00 (ref.) | — | — |
Large | 62 | 23 (37.1) | 1.20 (0.68–2.13) | — | — | |
| ||||||
Cats contact | No | 207 | 62 (30.0) | 1.00 (ref.) | 1.00 (ref.) | — |
Yes | 125 | 50 (40.0) | 1.56 (0.98–2.48) | 1.28 (0.74–2.20) | 0.371 | |
| ||||||
Water source | Mixed | 198 | 34 (17.2) | 1.00 (ref.) | 1.00 (ref.) | |
Pond | 55 | 24 (43.6) | 3.73 (1.95–7.14) | 4.25 (2.15–8.38) | <0.001 | |
Pipe water | 79 | 54 (68.4) | 10.42 (5.71–19.00) | 9.57 (5.00–18.33) | <0.001 | |
| ||||||
House type | Pen | 24 | 3 (12.5) | 1.00 (ref.) | — | — |
Both | 207 | 48 (23.2) | 2.11 (0.60–7.39) | — | — | |
Fence | 101 | 61 (60.4) | 10.68 (2.99–38.15) | — | — |
Mixed
District, age, and water sources were identified as risk factors for
Logistic regression analysis of risk factors with
Variables | Category | Number tested | Positive (%) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
---|---|---|---|---|---|---|
District | Haramaya | 121 | 22 (18.2) | 1.00 (ref.) | 1.00 (ref.) | — |
Gursum | 176 | 61 (34.7) | 2.39 (1.37–4.16) | 0.52 (0.20–1.36) | 0.185 | |
Babille | 113 | 30 (26.6) | 1.63 (0.87–3.03) | 0.15 (0.05–0.48) | <0.001 | |
| ||||||
Environment | Rural | 340 | 79 (23.2) | 1.00 (ref.) | — | — |
Urban | 70 | 34 (48.6) | 3.12 (1.83–5.31) | — | — | |
| ||||||
Sex | Male | 93 | 16 (17.2) | 1.00 (ref.) | 1.00 (ref.) | – |
Female | 317 | 97 (30.6) | 2.12 (1.18–3.82) | 1.65 (0.86–3.18) | 0.134 | |
| ||||||
Age | ≤1 year | 63 | 6 (9.5) | 1.00 (ref.) | 1.00 (ref.) | — |
>1 year | 347 | 107 (30.8) | 4.24 (1.77–10.12) | 3.45 (1.34–8.90) | 0.010 | |
| ||||||
Breed | Hararghe highland | 29 | 5 (17.2) | 1.00 (ref.) | 1.00 (ref.) | — |
Long ear Somali | 349 | 95 (27.2) | 1.80 (0.67–4.84) | 1.10 (0.36–3.39) | 0.863 | |
Undetermined | 32 | 13 (40.6) | 3.28 (0.99–10.84) | 2.77 (0.68–11.31) | 0.155 | |
| ||||||
Flock size | Small | 324 | 95 (29.3) | 1.00 (ref.) | 1.00 (ref.) | — |
Large | 86 | 18 (20.9) | 0.64 (0.36–1.13) | 0.85 (0.45–1.60) | 0.607 | |
| ||||||
Cats contact | No | 270 | 70 (25.9) | 1.00 (ref.) | — | — |
Yes | 140 | 43 (30.7) | 1.27 (0.81–1.99) | — | — | |
| ||||||
Water source | Mixed | 188 | 29 (15.4) | 1.00 (ref.) | 1.00 (ref.) | — |
Pond | 152 | 50 (32.9) | 2.69 (1.60–4.52) | 6.03 (2.42–15.05) | <0.001 | |
Pipe water | 70 | 34 (48.6) | 5.18 (2.80–9.56) | 11.61 (4.35–30.95) | <0.001 | |
| ||||||
House type | Pen | 27 | 5 (18.5) | 1.00 (ref.) | — | — |
Both | 292 | 73 (25.0) | 1.47 (0.54–4.01) | — | — | |
Fence | 91 | 35 (38.5) | 2.75 (0.95–7.93) | — | — |
Mixed
Multivariable logistic regression analysis indicated that district, herd size, and water source were risk factors for
Logistic regression analysis of risk factors with
Variables | Category | Number tested | Positive (%) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
---|---|---|---|---|---|---|
District | Haramaya | 87 | 14 (16.1) | 1.00 (ref.) | 1.00 (ref.) | — |
Gursum | 153 | 9 (5.9) | 0.33 (0.13–0.79) | 0.19 (0.06–0.59) | 0.004 | |
Babille | 86 | 12 (14.0) | 0.85 (0.37–1.95) | 1.60 (0.49–5.16) | 0.434 | |
| ||||||
Environment | Rural | 303 | 30 (9.9) | 1.00 (ref.) | — | |
Urban | 23 | 5 (21.7) | 2.53 (0.88–7.30) | — | ||
| ||||||
Sex | Male | 97 | 11 (11.3) | 1.00 (ref.) | — | |
Female | 229 | 24 (10.5) | 0.92 (0.43–1.95) | — | ||
| ||||||
Age | ≤1 year | 34 | 3 (8.8) | 1.00 (ref.) | — | |
>1–5 years | 186 | 19 (10.2) | 1.18 (0.33–4.21) | — | ||
>5 years | 106 | 13 (12.3) | 1.44 (0.39–5.40) | — | ||
| ||||||
Herd size | Small | 218 | 27 (12.4) | 1.00 (ref.) | 1.00 (ref.) | — |
Large | 108 | 8 (7.4) | 0.57 (0.25–1.29) | 0.35 (0.13–0.97) | 0.044 | |
| ||||||
Cats contact | No | 223 | 19 (8.5) | 1.00 (ref.) | 1.00 (ref.) | — |
Yes | 103 | 16 (15.5) | 1.97 (0.97–4.02) | 2.23 (0.86–5.77) | 0.097 | |
| ||||||
Water source | Mixed | 234 | 14 (6.0) | 1.00 (ref.) | 1.00 (ref.) | — |
Pond | 69 | 16 (23.2) | 4.75 (2.18–10.32) | 5.60 (2.12–14.78) | <0.001 | |
Pipe water | 23 | 5 (21.7) | 4.37 (1.41–13.49) | 10.68 (2.23–51.22) | 0.003 | |
| ||||||
House type | Barn | 29 | 5 (17.2) | 1.00 (ref.) | 1.00 (ref.) | — |
Both | 246 | 23 (9.4) | 0.50 (0.17–1.42) | 0.23 (0.05–0.99) | 0.049 | |
Fence | 51 | 7 (13.7) | 0.76 (0.22–2.67) | 0.42 (0.08–2.32) | 0.318 |
Mixed
The sole risk factor identified in camels is age. Camels in the age group of >4 years (OR = 2.49, 95% CI: 1.14–5.45,
Analysis of risk factors with
Variables | Category | Number tested | Positive (%) | Crude OR (95% CI) | Adjusted OR (95% CI) | |
---|---|---|---|---|---|---|
District | Gursum | 95 | 13 (13.7) | 1.00 (ref.) | — | — |
Babille | 197 | 29 (14.7) | 1.09 (0.54–2.20) | — | — | |
Sex | Male | 73 | 11 (15.1) | 1.00 (ref.) | — | — |
Female | 219 | 31 (14.2) | 0.93 (0.44–1.96) | — | — | |
Age | ≤4 years | 110 | 9 (8.2) | 1.00 (ref.) | 1.00 (ref.) | — |
>4 years | 182 | 33 (18.1) | 2.49 (1.14–5.42) | 2.49 (1.14–5.45) | 0.022 | |
Herd size | Small | 203 | 30 (14.8) | 1.00 (ref.) | — | — |
Large | 89 | 12 (13.5) | 0.90 (0.44–1.85) | — | — | |
Cat contact | No | 246 | 32 (13.0) | 1.00 (ref.) | 1.00 (ref.) | — |
Yes | 46 | 10 (21.7) | 1.86 (0.84–4.10) | 1.87 (0.84–4.18) | 0.127 | |
Water source | Mixed | 215 | 30 (14.0) | 1.00 (ref.) | — | — |
Pond | 77 | 12 (15.6) | 1.14 (0.55–2.35) | — | — |
Mixed
The present study had given an insight on toxoplasmosis and revealed the widespread occurrence of
In goats, the percentage of
The seroprevalence of
In the present study, the proportion of camels positive for anti-
The flock/herd level seroprevalence in sheep, goats, cattle, and camels in the current study was high. The flock seroprevalence recorded in sheep is like that of the previously reported value of 70.48% in East and West Shewa zones of Oromia Region, Ethiopia [
In this study, a significant difference in
In goats, those >1 year old were 3.45 times more infected than those ≤1 year old. Besides, goats that drank pond and pipe water had 6.03 times and 11.61 times more chance of acquisition of
The progressive increase in seroprevalence with age seen in sheep, goat, cattle, and camel indicates sustained exposure to the
The observed increased risk of infection in sheep, goats, and cattle that were given pipe water might be explained by the presence of several roaming cats capable of contaminating the pipe water source with infective
Consistent with the present finding, Gebremedhin et al. [
It could be concluded that
The authors declare that there are no conflicts of interest.
The financial support of Addis Ababa University and Ethio-Italian project is highly acknowledged. The authors acknowledge the National Animal Health and Disease Investigation Center at Sebeta for availing their laboratory facilities. The authors also would like to extend their gratefulness to the veterinary professionals in the study areas for their collaboration in this study.