The influence of weather and egg contamination on the development of third-stage larvae of Cooperia oncophora on pasture.

The influence of weather and egg contamination on the dynamics of herbage contamination with infective larave of Cooperia oncophora was investigated on artificially contaminated grass plots and in a grazing experiment with 24 first-year grazing calves from May to October 1987 in Lower Saxony, Germany. On the experimental plots the larval translation was highest at the beginning of July and in the second part of September, following high mean weekly temperatures. Between July and September peak recovery of larvae from herbage occurred 4 weeks after contamination. A seasonal pattern of larval translation similar to that on the experimental plots could be demonstrated on the grazed pastures when the number of larvae per m2 of pasture had been adjusted to the previous egg output by means of a contamination index. The resulting 'relative larval density' is regarded as a good indicator for larval development on pasture. From July to September the larval population on pasture resulted mainly from the egg contamination 2-3 weeks earlier. The short persistence of the infective larvae on herbage was probably due to the frequent and heavy rainfall throughout the season, causing a passive washout of larvae into the soil. On single pastures the larval density started to increase within 1 week after the calves had first contact with these fields. The impact of the calves on the distribution of larvae is discussed.

Transmission trials, ITS2-PCR and RAPD-PCR show identity of Toxocara canis isolates from red fox and dog.

Toxocara canis isolates from dog and from red fox were compared in transmission trials and with molecular analysis using RAPD-PCR technique and comparison of the ITS2 sequence. After oral infection of bitches with 20,000 embryonated T. canis eggs of vulpine and canine origin, the vertical transmission to pup's was examined. All animals of both groups developed typical clinical symptoms of toxocarosis. The haematological, serological, parasitological and post mortem results showed no differences between both isolates except for the infectivity of T. canis stages in mice where the fox isolate showed a significant higher infectivity than the dog isolate. The RAPD-PCR showed a similarity coefficient of 0.95, similar to the range of intraspecific variation in Toxocara cati and Toxascaris leonina specimens as outgroups. The ITS2 comparison showed a 100% identity between both isolates with no intraspecific variations. Therefore, the study shows that the fox and the dog isolate of T. canis were identical in infectivity, transmission and molecular structure; a host adaptation could not be found and the fox has to be seen as a reservoir for T. canis infections in dogs. Considering the increasing number of foxes in urban areas the importance of helminth control in dogs is stressed.

The prevalence and transmission to exotic equids (Equus quagga antiquorum, Equus przewalskii, Equus africanus) of intestinal nematodes in contaminated pasture in two wild animal parks.

Wild equids maintained in large enclosures may suffer from helminth diseases because common hygiene practices have only limited effects on parasite populations. Weekly monitoring of helminth prevalences and pasture infestation was performed for 1 yr in several extensive maintenance systems of two wildlife parks with similar climates to determine when veterinary intervention to control parasites would be useful. We also sought evidence of natural immunogenic reactions among herds of Chapman zebras (Equus quagga antiquorum), Przewalski's horses (Equus przewalskii) and dwarf donkeys (Equus asinus africanus). Fecal and vegetation samples and cultures for third-stage larvae revealed permanent egg shedding in the three species and pasture infestation during the warm, moist periods (July-September) in all enclosures. Stable social structure and low equid population density may be sufficient to make prophylaxis unnecessary in adults, whereas biotic and abiotic environmental factors such as crowding, animal transfers, social integration of subadults, and weaning stress may facilitate temporary severe infections of individuals. Biweekly helminth monitoring is a useful diagnostic tool for extensive management of exotic equids.

[Biology, pathogenicity, diagnosis and control of Ancylostoma caninum]. / Biologie, Pathogenität, Diagnostik und Bekämpfung von Ancylostoma caninum.

Infections with Ancylostoma caninum are transmitted orally or percutaneously. The transmission of infectious stages with the milk of particular importance for the distribution of the species. It occurs during the dissemination of larvae that follows every infection as well as after reactivation of resting somatic larvae in the bitch at the end of the pregnancy. The galactogenic transmission of larvae occurs even when, due to existing immunity, no patent infections develop in the bitch. Immunity does not or only to a low extent influence impatient infections or the migration of reactivated somatic larvae. It also allows a limited reestablishment of a deposit of larvae in the bitch. Following percutaneous infection dermatitis occurs in the area of larval penetration and the lung is affected by migrating larvae. Intestinal stages of Ancylostoma caninum damage the host by ingestion of the mucosa of the small intestine and withdrawal of blood. Main symptoms of ancylostomiasis are a mucous haemorrhagic diarrhoea and anaemia, that become visible 8 to 10 days post infection. The examination for impatient infections with Ancylostoma caninum can be done by immunofluorescence and ELISA. With both methods antibodies against third stage larvae can be detected from the first or second week post infection onward. Patent infections with Ancylostoma caninum can easily be detected by faecal examination for the presence of the characteristic oval, thin-walled eggs containing few blastomeres. Galactogenic infections with Ancylostoma caninum can be prevented or reduced by a regular treatment of the bitch with albendazole, fenbendazole or oxfendazole during the activation of larvae in the last third of the pregnancy or by repeated treatment with ivermectin shortly before and after birth. To prevent patent infections, galactogenic infected puppies have to be treated early and repeatedly.

[Contamination of public children's playgrounds in Hannover with helminth eggs]. / Kontamination öffentlicher Kinderspielplätze Hannovers mit Helmintheneiem.

Fifty-two public sand pits on children playgrounds in Hannover were investigated for the presence of parasites. A large proportion (63.5%) of these playgrounds were contaminated with parasite eggs. Eggs from Toxocara spp., Toxascaris leonina and other common helminth parasites were found in 55.8%, 9.6% and 26.1% of these playgrounds, respectively. A total of 208 sand samples were collected, and 30.8% of them contained eggs from Toxocara spp. (24.5%), Toxascaris leonina (2.4%) or other common helminths (9.1%). In 45.1% of the Toxocara positive samples, the eggs were embryonated. Eggs from Toxocara spp. were found in 33.0%, 31.0% or 14.0% of samples from districts with low, medium or high numbers of dogs per hectare, respectively.

[Use of an albendazole bolus against gastrointestinal nematode infections in first year cattle]. / Einsatz eines Albendazol-Bolus gegen Magen-Darm-Wurminfektionen bei erstsömmerigen Rindern.

Thirty first year grazing calves were allocated to two groups of 15 calves each on the basis of bodyweight and were administered albendazole boli or placebo boli, respectively, 30 days after turnout. The albendazole bolus prevented the nematode egg output almost completely for about 4 months, whereas the controls had mean egg counts of up to 206. Pepsinogen concentrations were significantly higher in the control group and reached mean values of 3055 mU tyrosine compared to less than 1000 mU tyrosine in the albendazole treated group after bolus administration. Pasture contamination with trichostrongylid larvae was markedly lower on pastures of the albendazole group than on the controls. Mean weight gains were significantly higher in the albendazole group than in the controls with a difference of 10.7 kg per animal at the end of the season.

[Helminth fauna of red foxes (Vulpes vulpes LINNE 1758) in southern Saxony--2: Nematodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE 1758) im Süden Sachsen-Anhalts--Teil 2: Nematoden.

Between January 1993 and November 1994 a total of 1300 red foxes from the administrative districts Halle and Dessau were examined for the presence of nematodes in the stomach and the small intestine. The following nematodes were found: Toxocara canis (26.5%), Toxascaris leonina (10.5%), Uncinaria stenocephala (15.9%) Ancylostoma caninum (1.7%). The search for Trichinella spp. larvae was negative in all 780 examined foxes.

[Helminth fauna of the red fox (Vulpes vulpes LINNE 1758) in south Sachsen-Anhalt--1: Cestodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE 1758) im Süden Sachsen-Anhalts--Teil 1: Zestoden.

Between January 1993 and November 1994 a total of 1300 red foxes from the administrative districts Halle and Dessau were examined for the presence of Echinococcus multilocularis and other cestodes. Echinococcus multilocularis-infections were detected in only 4 of 1300 (0.3%) foxes. Furthermore the following cestodes were found: Mesocestoides spp. (54.1%), Taenia crassiceps (17.7%), Taenia polyacantha (11.9%), Hydatigera taeniaeformis (0.2%), Taenia serialis (0.15%), Taenia pisiformis (0.15%), not determinable taeniids (9.2%), Dipylidium caninum (0.2%) and Hymenolepis spp. (0.08%).

[The helminth fauna of the red fox (Vulpes vulpes LINNE 1758) in the administrative district of Karlsruhe. 1. Cestodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE 1758) im Regierungsbezirk Karlsruhe. Teil 1: Zestoden.

Between February 1989 and January 1990 a total of 801 red foxes were examined for the presence of cestodes. Echinococcus multilocularis could be noted with an infection rate of 11.6% in the small intestine of the red fox. The following other cestodes were found (in order of frequency) Taenia crassiceps (19.9%), Mesocestoides spp. (16.6%), Taenia polyacantha (7.0%), Hydatigena taeniaeformis (0.7%), Dipylidium caninum (0.5%) and Diphyllobothrium latum (0.5%). Infections with Echinococcus multilocularis very often showed worm numbers between 11 and 100 specimen per fox. The number of worms of the other cestodes mostly varied between one and ten specimen per animal.

[The helminth fauna of red foxes (Vulpes vulpes LINNE 1758) in the administrative district of Karlsruhe. 2. Nematodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE 1758) im Regierungsbezirk Karlsruhe. Teil 2: Nematoden.

Between February 1989 and January 1990 a total of 801 foxes were examined for the presence of nematodes in the stomach and the small intestine and 835 foxes for the presence of Trichinella spiralis larvae. The animals came from the german federal administration area of Karlsruhe. The following nematodes in order of frequency were found: Toxocara canis (30.2%), Uncinaria stenocephala (24.3%), Toxascaris leonina (2.0%) and Ancyclostoma caninum (1.1%). The investigation of the muscles of all animals for Trichinella spiralis was negative, however.

[Prevalence of Echinococcus multilocularis and other metacestodes and cestodes in the muskrat (Ondatra zibethicus LINK 1795) in Lower Saxony]. / Zur Prävalenz von Echinococcus multilocularis und anderen Metazestoden und Zestoden des Bisams (Ondatra zibethicus LINK 1795) in Niedersachsen.

Aim of the study was to examine the prevalence and regional distribution of Echinococcus multilocularis and other metacestodes and cestodes in muskrats in Lower Saxony, Germany. A total of 991 muskrats with similar numbers from all districts of the country were examined between January and December 1995. E. multilocularis metacestodes were found in 4.1% of the muskrats in the liver and other organs of the abdominal cavity. The majority of the E. multilocularis positive animals came from the south of Lower Saxony, where E. multilocularis is endemic, and single animals from the middle or the northern part of the country. All metacestodes found were fertile. Additionally, metacestodes from T. taeniaeformis were found in the livers of 42.3% of the muskrats, metacestodes from T. crassiceps were present in the abdominal cavity of 2.7%, T. polyacantha in 0.4% and T. martis in 3.4% of the animals. Adult cestodes of the family of the Anoplocephalidae were found in the small intestine of 1.5% of the muskrats. Due to autolysis a species differentiation of the latter was not possible.

[Parasitological fecal studies of equids, dogs, cats and hedgehogs during the years 1984-1991]. / Ergebnisse parasitologischer Kotuntersuchungen von Equiden, Hunden, Katzen und Igeln der Jahre 1984-1991.

The results of the coproscopical examinations in horses, dogs, cats and hedgehogs between 1984 and 1991 are presented. In 9192 samples from horses 55.5% stages of strongylids, 4.0% of Parascaris equorum, 2.2% of anoplocephalids, 1.6% Strongyloides westeri, 0.7% of Oxyuris equi, 0.6% of Eimeria leuckarti, 0.2% of Fasciola hepatica and 0.04% of Dictyocaulus arnfieldi were found. In 48.0% of the 46 samples from donkeys eggs from strongylids were detected, in 17.4% larvae from Dictyocaulus arnfieldi, in 2.2% eggs from Strongyloides westeri, Parascaris equorum and oocysts from Eimeria leuckarti, respectively. In 3329 samples of dogs 6.9% developmental stages of Toxocara canis, 6.0% of Giardia spp., 4.2% of Isospora spp., 3.0% of Sarcocystis spp., 2.5% each of ancylostomids and Trichuris vulpis, 1.1% of Toxascaris leonina and 1.1% of Dipylidium canium, up to 1.0% of taeniids, 0.6% of each Mesocestoides spp. and Metastrongylidae, 0.3% of Strongyloides stercoralis and 0.2% of Capillaria spp. and Hammondia heydorni were detected. In 9.5% of the 1147 samples of cats eggs from Toxocara mystax were found, in 4.7% eggs of taeniids, in 4.6% cysts of Isospora spp., in 2.4% of Giardia spp., in 1.4% eggs of Dipylidium caninum, in 1.0% of Capillaria spp. and Aelurostrongylus abstrusus, in 0.6% development stages of Toxoplasma gondii, in 0.5% of ancylostomids and in 0.3% of Sarcocystis spp. and Opisthorchis felineus. In 1175 samples of hedgehogs 48.8% eggs of Capillaria spp., 35.9% of Crenosoma striatum, 17.9% oocysts of Isospora spp., 2.3% eggs of Brachylaemus erinacei were found.

[The helminth fauna of red foxes (Vulpes vulpes Linnaeus 1758) in north Hesse and east Westphalia. 1. Cestodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE 1758) in Nordhessen und Ostwestfalen. Teil 1: Zestoden.

Between November 1989 and June 1990 a total number of 397 foxes were examined for the presence of cestodes. The animals came from the districts of Arnsberg, Detmold and Kassel. In 16.4% of the foxes infections with Echinococcus multilocularis were found, in 28.5% Taenia crassiceps, in 14.4% Taenia polyacantha, in 4.3% Mesocestoides spp., in 3.3% Multiceps multiceps, in 2.5% Hydatigera taeniaeformis, in 0.8% Taenia hydatigena and in 0.3% Taenia martis. Infections with Echinococcus multilocularis very often showed high worm numbers of more than 1000 per fox. The number of worms for the other cestodes mostly varied between one and ten specimen per animal.

[Nematode and trematode fauna of the muskrat (Ondatra zibethicus LINK, 1795) in Lower Saxony]. / Ein Beitrag zur Nematoden- und Trematodenfauna des Bisams (Ondatra zibethicus LINK, 1795) in Niedersachsen.

From January 1995 to December 1995, 991 muskrats were examined for the occurrence and the regional prevalence of nematodes and trematodes. The muskrats were trapped in all parts of Lower Saxony. 77.2% of the studied population were less than one year old, 22.8% were older. The male to female ratio was 54.5% to 45.5%. One genus of nematodes, Trichuris spp., was found in the colon in 1.9% of the animals in the south of the investigated area. A species differentiation was not possible, as exclusively female parasites had been found. Additionally, two genera of trematodes (Echinostoma spp. and Quinqueserialis quinqueserialis) belonging to two different families were detected in 2.5% of the muskrats. In the north of the investigated area the prevalence was significantly higher than in the south. As to the echinostomatides, no species-differentiation was made because, according to KANEV (1985), many echinostomatides have not been described correctly in the past. Some echinostomatides cannot be differentiated until today. There was no statistically significant correlation between parasite infections and sex of the animals. Concerning Echinostoma spp. and Quinqueserialis quinqueserialis, a highly significant correlation was found between the age of the muskrats and the trematode-infections. Young animals were infected more often than older animals, none of the younger animals was infected with Trichuris spp.

[The helminth fauna of the red fox (Vulpes vulpes LINNE, 1758) in Nordhessen and Ostwestfalen. 2. Nematodes]. / Zur Helminthenfauna des Rotfuchses (Vulpes vulpes LINNE, 1758) in Nordhessen und Ostwestfalen. Teil 2: Nematoden.

Between November 1989 and June 1990 a total number of 397 foxes were examined for the presence of nematodes in the stomach and the small intestine and 403 foxes for the presence of Trichinella spiralis larvae. The animals came from the districts of Kassel, Arnsberg and Detmold. In 32.7% of the foxes infections with Toxocara canis were found, in 11.1% Toxascaris leonina, in 3.8% Ancylostoma caninum, in 3.5% Uncinaria stenocephala and in 2.3% Capillaria species. In most cases the number of nematodes per fox was low. Only Toxascaris leonina was frequently found with more than 20 specimen per animal. Trichinella spiralis larvae were not found in any of the foxes.