Occurrence of endoparasites in heifers imported to Poland from the Netherlands ( Short Communication )

Prevalence of gastrointestinal parasites was studied in 106 heifers imported to Poland from the Netherlands. Prevalence of gastrointestinal nematodes and Eimeria protozoans was determined from coproscopic examinations using Willis-Schlaf flotation. The species composition of coccidia was determined from morphological characters and the time of oocyst sporulation. Fluke liver eggs were detected by decantation. The study showed the mean prevalence of Eimeria protozoans in the heifers imported from the Netherlands to Poland to be 17.92 %; the mean prevalences of Cryptosporidium sp. (11.32 %), gastrointestinal nematodes (55.66 %) and Fasciola hepatica (32.08 %), respectively. The following 6 coccidia species were isolated from faecal samples: E. bovis, E. aubernensis, E. ellipsoidalis, E. subspherica, E. zürni, and E. brasiliensis. The prevalence of gastrointestinal parasites in the cattle imported from the Netherlands to Poland was very high, therefore it is purposeful to mandatorily examine the imported cattle for the presence of those parasites.


Introduction
Parasitoses belong to the most common diseases of ungulates (DISTL 2001, GÓRSKI et al. 2004a, 2004b, AGNEESSENS et al. 2000, BORGSTEEDE et al. 1998, 2000, MEKROUD et al. 2004, PILARCZYK et al. 2002, HILGENSTOCK et al. 2006) and result in high losses caused mainly by reduced condition, productivity, and resistance of the affected animals.Parasitic diseases proceed usually subclinically, for which reason they very often go undetected by breeders and veterinarians alike.The Black-White cattle are the commonest breed in Poland, improved by admixture of genes of the Holstein-Friesland cattle imported from Germany and the Netherlands, heifers being most frequently imported.The absence of control makes it possible to introduce, with the imported cattle, of new parasites.The problem of parasitic infestations (with protozoans and worms) of heifers imported to the Czech Republic from Germany, France, Denmark, and the Netherlands was discussed by PAVLAŚEK (1995).
At present, the cattle imported to Poland do not have to be examined for the presence of endoparasites such as coccidia, cryptosporidia, gastrointestinal nematodes, and liver fluke.
This study was aimed at identification of parasitic fauna in heifers imported to Poland from the Netherlands.

Material and methods
Coproscopic examination was carried out in 106 Holstein-Friesland heifers imported from the Netherlands -Overijssel Province to the Porta-Agra farm in Poland.During the 2-week quarantine, the heifers were fed Triticale flakes, corn silage, barley hay silage, and hay; the heifers had access to water and salt.
The prevalence of gastrointestinal nematodes and Eimeria protozoans was estimated from coproscopic examination, performed with the Willis-Schlaf flotation technique (ZIOMKO and CENCEK 1995).The samples for study were taken individually from rectum of each animal.Coccidia were identified to species using the key published by PELLERDI (1974).Examinations were supplemented by culturing oocysts at 24-26 °C in a humid chamber, with 2.5 % aqueous solution of potassium dichromate (K2Cr2O7) to prevent mould growth.
Nematodes were identified to species based on larval culture carried out as recommended by Baermann (GUNDŁACH et al. 2004).
Faeces were examined for the presence of Cryptosporidium sp. using a modified Ziehl-Neelsen staining technique (ANONYMUS 1991) and a commercially available immunoenzymatic microplate assay (PrpSpecT Cryptosporidium Microplate Assay, Alexon Inc.).The microplate assay was performed as specified by the manufacturer.

Results
The mean prevalence of gastrointestinal parasites in the heifers imported to Poland was 83.96 % (n=89).
The mean prevalence of Eimeria infestation of the heifers examined was 17.92 % (n=19).
As shown by coproscopy, the heifers were infested by a mix of coccidia, the following 6 coccidia species being isolated from faecal samples: E. bovis, E. aubernensis, E. ellipsoidalis, E. subspherica, E. zürni, and E. brasiliensis.The dominant species was E. bovis (Figure 1).

Figure 1 Prevalence of Eimeria species invasion in heifers Prävalenz der verschiedenen Eimeriaarten bei untersuchten Färsen
In most cases (84.21 %, n=16), the coccidia-infested animals were affected by one-and two-species invasions.The maximum number of coccidia species found in the heifers was 4 (Figure 2).The coproscopic examination showed the heifers imported from the Netherlands to Poland to be infected by Cryptosporidium sp., found in 11.32 % (n=12) of the individuals.The coproscopic examination showed the prevalence of Fasciola hepatica invasion in the heifers imported from the Netherlands to be 32.08 % (n=34).

Discussion
The heifers imported to the Czech Republic from France, Denmark, the Netherlands, and Germany showed the parasites to occur at a prevalence ranging from 91.2 to 100 % (PAVLAŚEK 1995).
Among numerous parasites occurring in animals, particularly noteworthy are coccidia due to their wide distribution, independent of climatic conditions.
The selected Western Pomeranian farms studied by PILARCZYK et al. (2002) showed coccidia prevalence in 5.5-12.0% of cows in small-scale farms and in 23.4 % of the cows kept in a large-scale form.The cows proved to be infested by the following 6 coccidia species: E. bovis, E. aubernensis, E. zürni, E. elipsoidalis, E. subspherica, andE. cylindrica (PILARCZYK et al. 1999). CORNELISSEN et al. (1995) found heifers to be affected by invasions of 6 species.PAVLAŚEK (1995) found Cryptosporidium muris in 4.5 % of heifers imported from France and in 7.9 % of heifers imported from Germany to the Czech Republic.As reported by PILARCZYK et al. (2002), calves and cows kept in small private farms in Western Pomerania were not affected by a Cryptosporidium sp.invasion.On the other hand, MAJEWSKA et al. (1998) found oocysts of Cryptosporidium sp. in 34.4 % of the cattle in the region of Wielkopolska (including 39.7 % of calves and 6.6 % of cows).The presence of Cryptosporidium sp. has been reflected from other countries as well, e.g., in 1.9 % of the cattle in the US (FAYER et al. 2006), in 5 % in Mexico (MALDONA-CAMARGO et al. 1998), in 20 % in Canada (OLSON et al. 1997), in 13 % in Sweden (KLINGENBERG 1992), and in 19.7 % in Spain (QUILEZ et al. 1996).
The Netherlands is one of those European countries where liver fluke has been known for many years (MOLL et al. 2000), therefore it should be paid a particular attention when livestock imports are being carried out.In Poland, too, the liver fluke has been reportedat various intensities -cows, the extent of infestation being dependent on time and area of study.In their 2001 study of selected Western Pomeranian cattle farms, PILARCZYK et al. (2002) showed the absence of a Fasciola hepatica invasion On the other hand, the prevalence of the parasite in North-Eastern Poland was as high as 11 % (MICHALSKI et al. 1993, MICHALSKI andROMANIUK 2000).Eggs of Fasciola hepatica were also found by PAVLAŚEK (1995) in 12 heifers imported from France to the Czech Republic.The prevalence of Fasciola hepatica in the heifers imported from the Netherlands should be regarded as high.
In his study on heifers imported to the Czech Republic, PAVLAŚEK (1995) recorded the presence of 9 gastrointestinal nematodes.Most frequent were representatives of the genera Ostertagia, Haemonchus and Trichostrongylus.In the study described by PILARCZYK et al. (2002) and carried out in selected Western Pomeranian farms, the gastrointestinal nematode prevalence in cows was found to range within 12.7-32.1 %, 42.6 % prevalence being revealed in a large-scale farm.The study reported by DÜWEL (1990) from Germany revealed gastrointestinal nematode eggs to be present in faeces of 60 % of the ungulates, while ISTASSE et al. (1990) in Belgium recorded a 47.4 % prevalence of infestation in dairy cows.
It was found that prevalence of coccidiosis in imported animals was generally comparable to that observed in Dutch cattle by CORNELISSEN et al. (1995).The data on prevalence of coccidiosis in Polish cattle are largely comparable with the level of infection in Dutch cattle.It is worth noting the high prevalence of fascioliasis (32.08 %) in imported cattle.In West Pomerania, fascioliasis has occurred sporadically in cattle in recent years.In imported cattle, the level of infection with gastrointestinal nematodes was high (55.66%).In cattle from West Pomerania, the prevalence of gastrointestinal nematodes varied between 12.7 and 42.65 % according to farm (PILARCZYK et al. 2002).
Summaring the prevalence of infestation with gastrointestinal parasites in the cattle imported to Poland from the Netherlands was very high.It is therefore purposeful that imported animals be subjected to mandatory examination for the presence of those parasites.