Dogs are still the most common companion animals establishing more frequent and closer contact with humans than any other pets. Furthermore, various canine parasites are involved in the epidemiology of many parasitic diseases affecting a wide range of domestic and wild herbivorous and omnivorous. Also, the canids act as reservoirs and sources of several zoonotic parasites posing a serious threat to the human health (Xhaxhiu et al., 2011). The children are generally at higher risk of acquiring infections with some parasites (e.g.
The prevalence of parasitic infections in dogs depends on several factors such as the lifestyle, deworming frequency, climate conditions, and contacts with stray dogs or wildlife (Roussel et al., 2019). Additionally, some owners neglect the prophylaxis of their dogs resulting in contamination of environment with infective parasite stages of high tenacity. Also, the shepherd dogs often have no prophylactic therapy, and the occurrence and intensity of parasite infections, especially with tapeworms, usually results from scavenging sheep carcasses (Vasileiou et al., 2015; Rehbein et al., 2016).
Canine parasitic fauna has been a purpose of many studies conducted all around the world over the last few decades. Numerous Bulgarian investigations on the same focus have also been carried out, including different categories of dogs, originating from many regions of the country. In addition, gastrointestinal (GI) parasitism of
Canine vector-borne diseases (CVBDs) constitute an important group of illness caused by a diverse range of pathogens, which are transmitted to both animals and humans by different blood-sucking arthropods (Dantas-Torres, 2008). Those diseases are usually endemic in tropics and subtropics, but an increasing prevalence has also been recognized in temperate regions (Dantas-Torres, 2008; Beugnet & Chalvet-Monfray, 2013). The prevalence of CVBDs in Bulgaria has been frequently reported over the past few years, including infections with
This study was performed from July 2016 to September 2017 on 172 owned dogs (115 males and 57 females) aged from 1 month to 12 year, reared outdoor. The animals were recruited from outskirts of Rousse (43º50’N, 25º57’E), Razgrad (43º32’N, 26º32’E), Sofia (42º41’N, 23º19’E) (Northern Bulgaria), Stara Zagora (42º25’N, 25º38’E), and Plovdiv (42º8’N, 24º44’E) (Southern Bulgaria).
Fecal samples were obtained manually from
Blood samples were collected by venipuncture of
All data were analysed by means of MedCalc v.10.2.0.0, MedCalc Software (Belgium). The prevalence and its 95 % confidence interval (CI) were calculated for each parasitic species, including co-infections. The difference of prevalence among groups (regarding to the gender and age) was evaluated by Chi-square (χ2) test and was considered significant at P ≤ 0.05.
Аpprovals for using animals in the current study were obtained from the Bulgarian Food Safety Agency (registration of the permits: №85/09.01.2014 and №138/28.06.2016). The research has been complied with all the relevant national regulations and institutional policies for the care and use of animals.
The overall prevalence of GI parasites was 64.5 %. Eggs of hookworms were the most commonly observed in feces (54.1 %), followed by
Overall prevalence (%) of the pathogens in dogs (n=172)
Species | Southern Bulgaria (n=124) | Northern Bulgaria (n=48) | Total (n=172) | Test applied | |
---|---|---|---|---|---|
Positive (%) | Positive (%) | 95% CIs | |||
4 (3.2) | 6 (12.5) | 10 (5.8) | 2.3 - 9.3 | Knott’s test | |
14 (11.3) | 4 (8.3) | 18 (10.5) | 5.9 – 15.0 | Serology | |
1 (0.8) | - | 1 (0.6) | 0 – 1.7 | ||
14 (11.3) | 12 (25.0) | 26 (15.1) | 9.8 – 20.5 | ||
10 (8.1) | 9 (18.8) | 19 (11.0) | 6.4 – 15.7 | ||
9 (7.3) | 2 (4.2) | 11 (6.4) | 2.7 – 10.1 | ||
57 (46.0) | 36 (75.0) | 93 (54.1) | 46.6 – 61.5 | Flotation | |
1 (0.8) | 2 (4.2) | 3 (1.7) | 0 – 3.7 | ||
1 (0.8) | 1 (2.1) | 2 (1.2) | 0 – 2.8 | ||
- | 1 (2.1) | 1 (0.6) | 0 – 1.7 | Sedimentation | |
6 (4.8) | 1 (2.1) | 7 (4.1) | 1.1 – 7.0 | Flotation | |
4 (3.2) | - | 4 (2.3) | 0.1 – 4.6 | ||
16 (12.9) | 7 (14.6) | 23 (13.4) | 8.3 – 18.5 | ||
22 (17.7) | 1 (2.1) | 23 (13.4) | 8.3 – 18.5 | Serology | |
2 (1.6) | 1 (2.1) | 3 (1.7) | 0 – 3.7 |
Cases of single infection in dogs (n=172).
Species | Positive (%) | 95% CIs |
---|---|---|
2 (1.2) | 0 – 2.8 | |
6 (3.5) | 0.7 – 6.2 | |
6 (3.5) | 0.7 – 6.2 | |
5 (2.9) | 0.4 – 5.4 | |
35 (20.3) | 14.3 – 26.4 | |
6 (3.5) | 0.7 – 6.2 | |
2 (1.2) | 0 – 2.8 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 |
Cases of mixed infections in dogs (n=172)
Combinations | Positive (%) | 95% CIs |
---|---|---|
2 (1.2) | 0 – 2.8 | |
5 (2.9) | 0.4 – 5.4 | |
2 (1.2) | 0 – 2.8 | |
1 (0.6) | 0 – 1.7 | |
7 (4.1) | 1.1 – 7.0 | |
2 (2.1) | 0 – 2.8 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
5 (2.9) | 0.4 – 5.4 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
4 (2.3) | 0.1 – 4.6 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
2 (1.2) | 0 – 2.8 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
2 (1.2) | 0 – 2.8 | |
2 (1.2) | 0 – 2.8 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
3 (1.7) | 0 – 3.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
3 (1.7) | 0 – 3.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 | |
1 (0.6) | 0 – 1.7 |
The serum analysis identified antigens of
The age was identified as a risk factor for
The findings of this study showed that more than half of the dogs (64.5 %) were infected by at least one species of GI parasite.
Numerous recent surveys performed on the Balkans have disclosed comparable results indicating the presence of GI parasitism in 67.1 % of dogs in Romania (Ursache et al., 2016), 75.4 % in Serbia (Sommer et al., 2017), between 48.1 % and 64.9 % in Croatia (Brezak et al., 2017), 26 % in Greece (Papazahariadou et al., 2007), 30.4 % in Turkey (Senlik et al., 2006) and 40.7 % in Albania (Shukullari et al., 2015). All the mentioned results were obtained by coprological exaninations. According to the regional reports, between 24.8 % and 65 % of dogs in Bulgaria harbor several species of endoparasites including ascarids, hookworms, whipworms, tapeworms and coccidians (Kirkova et al., 2006; Lalkovski & Sabev, 2009; Kirkova et al., 2013; Radev et al., 2016), which seems to be in general agreement with our finding. The differences between aforementioned results are not unexpected and could be due to various factors. Those investigations include either well- or not well-cared dogs of different ages and categories (e.g. hunting, shepherd, military, pet, shelter and stray dogs) with different deworming frequency (e.g. regular or not), clinically healthy or under veterinary care (with GI disorders). Taking into consideration the above, it can be argued that the combined influence of the age and purpose of dogs, the general hygiene, and the access to regular deworming may exert a marked effect on the prevalence and species variety of GI parasites among the canine population (Shukullari et al., 2015). In addition, the strong influence of the geographic location and climate conditions is confirmed by the results of a recent study, demonstrating lower prevalence of GI parasitic infections (9.4 %) even in stray and not well-cared dogs in Germany (Becker et al., 2012).
In this study, hookworms were recognized as the most common enteric pathogens, which were found in the fecal samples of more than half of dogs (54.1 %) In similar investigation conducted in Stara Zagora (Bulgaria), the prevalence of
The canine whipworm,
The overall number of dogs infected with
The results of our study showed that 1.2 % of dogs are infected with
Numerous studies regarding to the prevalence of aforementioned helminth species have been conducted in closer geographical regions, including Croatia (Brezak et al., 2017); Romania (Ursache et al., 2016), Serbia (Sommer et al., 2017); Greece (Papazahariadou et al., 2007); Albania (Shukullari et al., 2015) and Turkey (Senlik et al., 2006). Summarized results indicate the presence of GI parasitism ranging from 1.2 % to 41 % for hookworms, from 2.9 % to 9.6 % for
Our results showed
Our investigation presents the first serologically proven case of angiostrongylosis due to the cardiopulmonary nematode
Protozoa infections were less often identified in this study than helminth infections (4.1 % for
Almost half of the dogs (44.8 %) were positive for vector-borne parasites and bacteria such as
Our results also showed infections with
The results obtained here indicated that elder dogs (irrespective of sex) were commonly affected by
This study presents an overview of the prevalence of GI parasites and some vector-borne helminths and bacteria in outdoor dogs in Bulgaria as well as the first report of