BACKGROUND: Recent investigations  have identified anthelminitic effects of many medicinal plants particularly from condensed tannin sources. In addition, gastrointestinal nematodes of ruminants have a negative effect on the farming industry worldwide. Objectives: The aim of the present study was  to determine the potential anthelmintic effects of Quercus robur extract on alimentary canal nematodes in naturally infected sheep by faecal egg count reduction test (EPGRT). Methods: The crude aqueous extract was prepared from Quercus robur as tannin extract. The nature and intensity of helminth infection was determined by coprological examination. The faecal samples of 600 sheep were collected from different regions of Kurdistan province. The samples were examined by flotation method (Clyton-Lane technique). Fifteen sheep with the most count in egg per gram (include Marshallagia, Nematodirus and Trichostrongylids) were divided into three groups of five animals: First group (test group) were drenched with Quercus robur extract at 3.75g/kg, second group (positive control group) received Albendazole 2.5%, orally at 5mg/kg and third group (negative control) without treatment. Results: The results of faecal examination  3 days after administration indicated significant reduction of EPG in both group’s treatment and positive control groups, 90.76% and 90.83% respectively, whereas there was no effect in the third group. Results were evaluated by Chi-square analysis and showed significant differences between treatment and negative control groups (p≤0.05). Nosignificant differences were observed between treatment group and positive control group (p≥0.05). Conclusions: Results reveal that aquatic extract of Quercus robur has anthelminitic activity and further large scale studies are suggested to confirm pharmacologic effects of this herbal extract.

BACKGROUND: Mice are the most common laboratory animals used in research. Parasitic infections in laboratory animals affect both the research results and the health of researchers.OBJECTIVES: The present study aimed to investigate the infection status of intestinal parasites of mice in three main animal houses in Tehran.METHODS: In this study, 75 mice (25 from each animal house) were randomly purchased from an animal breeding house in Tehran and investigated. Mice were euthanized and autopsied. In order to study the gastrointestinal protozoa, wet smears were prepared from different parts of the intestine and feces and stained with Giemsa and Ziehl-Neelsen if necessary. Afterwards, the intestinal contents were examined and helminths were separated. If necessary, specific staining was used to diagnose helminths.RESULTS: Among the detected parasites, Aspiculuris tetraptera was the most prevalent (% 93.3). The mice were also infected with Syphacia obvelata (% 62.6), Hymenolepis nana (% 61.3), Tritrichomonas muris (% 22.6), Giardia muris (% 21.3), Spironucleus muris (% 18.6), Hymenolepis diminuta (% 17.3), and Cryptosporidium (% 6.6).CONCLUSIONS: Out of 75 adult mice studied, all had at least one parasite. This can affect the research results and jeopardize the health of researchers and related personnel.

The aim of the present study was to examine gastrointestinal parasites in stool samples collected from stray dogs cared in animal shelters of Kırıkkale and Ankara and pet dogs that have been taken to the clinics and animal hospitals for control and treatment, and to evaluate the results for public health. Stool samples of 200 animals were obtained by arriving relevant centres for this purpose. Stool samples obtained were evaluated macroscopically and microscopically. Fülleborn Flotation and Benedek Sedimentation techniques were applied onto the stool samples for microscopic examination; Mc Master technique as used to determine the egg count per stool gram in stool samples which were positive for parasite. Stool samples were also examined for protozoan trophozoites and cysts through Giemsa staining, and for Cryptosporidium spp. oocysts through Carbol-Fuchsin staining. According to the results of this study, helminths and protozoans were detected with following rates; Toxocara canis by 18%, Toxascaris leonina by 9%, Taenia spp. by 0.5%, Ancylostoma spp. by 7.5%, Dipylidium caninum by 0.5%, Hymenolepis diminuta by 0.5%, and Fasciolid type egg by 1.5%; protozoans detected in the stool samples were Isospora spp. by 14.5%, Giardia spp. by 16.5%, and Cryptosporidium spp. by 2%. Furthermore, the egg of Linguatula serrata (0.5%) was detected in one dog, and mature Demodex spp. (2%) was detected in 4 dogs.

The abundance and distribution of parasitic helminths in populations of African buffaloes, Syncerus caffer, have not been well documented. A total of 28 buffaloes of different ages and sexeswere sampled in the Kruger National Park, South Africa, for nematodes of the small intestine. Three nematode species were identified, namely Cooperia fuelleborni, Cooperia hungi and Trichostrongylus deflexus, with C. hungi being a new country record for African buffalo in South Africa. The overall prevalence was 71%and the average number of worms was 2346 (range: 0–15 980). This is a small burden for such a large mammal. Sex, age and body condition of the buffaloes had no significant effect on worm occurrence.

Fourteen cats were inoculated orally with 1 of 2 infective doses of Toxocara canis to induce eosinophilia. Cats were subsequently challenge exposed twice via intraperitoneal injection with 1 of 2 T canis antigen preparations. Peritoneal lavage was performed 2 days after antigenic challenge exposure, and eosinophils in the peritoneal lavage fluid were quantified. None of the cats developed clinical signs of disease after infection. All cats developed peripheral eosinophilia after infection. Significant (P < 0.05) difference in mean eosinophil count from the lavage fluid was observed between lavage 1 (prechallenge exposure) and lavages 2 and 3 (postchallenge exposure) in both groups of cats. Significant difference in eosinophil count was not found between cats given different doses of eggs. After initial challenge exposure, significantly (P < 0.05) more eosinophils were obtained from cats given antigen preparation 2 (prep-2) than from those given antigen prep-1. This difference was no longer observed after the second challenge exposure with higher doses of either antigen prep-1 or prep-2. In cats given antigen prep-2, significant difference was not found between lavages 2 and 3. However, in cats given antigen prep-1, eosinophil count was significantly (P = 0.005) greater in fluid obtained from lavage 3, compared with eosinophil count from lavage 2. Mean +/- SEM percentage of eosinophils in the fluid from lavage 3 in all cats was 70.8 +/- 2.2%. Other cell types included macrophages, neutrophils, lymphocytes, and mast cells. Gross postmortem findings were mild. One- to 3-mm nodular white foci of inflammation were observed on the serosal surfaces of the liver, spleen, kidneys, and omentum. Microscopic examination of tissues revealed pulmonary artery hypertrophy (n = 4), eosinophilic peribronchitis and perivasculitis (n = 10), mild granulomatous interstitial nephritis (n = 6), interstitial pancreatitis (n = 1), focal lymphocytic myocarditis (n = 1), focal eosinophilic granulomatous hepatitis (n = 1), and eosinophilic hyperplasia of bone marrow (n = 14). Large numbers of eosinophils could be harvested from the peritoneal cavity of cats inoculated orally with 500 embryonated T canis eggs and subsequently challenge-exposed intraperitoneally with preparations of parasite antigens. After the second challenge exposure, at least 108 eosinophils could be harvested from each cat, yielding eosinophils in the quantity required to begin isolation of granule constituents.

The possible development of type-1 hypersensitivity reactions in the abomasal mucosa caused by soluble L3 products of Ostertagia ostertagi was studied in 4-month-old calves sensitized by repeated exposure to L3 over a 50-day period followed by anthelmintic treatment. Four groups each of 4 calves were used. Group 1 served as nonsensitized controls and group 2 as sensitized controls, group 3 was challenge exposed at 2-week intervals beginning at week 10 with a soluble L3 product (OAG), and group 4 was challenge exposed at 2-week intervals with an oral dose of L3, followed by anthelmintic treatment 3 days later. All calves infected with L3 became sensitized, as indicated by a positive reaction to an intradermal skin test. However, a passive cutaneous anaphylaxis was only partly effective in indicating the presence of homocytotropic antibody in the infected calves. Sensitized calves had significantly (P < 0.05) higher eosinophil counts and plasma pepsinogen values for the entire 14 weeks than uninfected controls. Globule leukocyte and mast cell counts from the abomasal mucosa were also significantly (P < 0.05) higher. Studies for possible immunomodulation revealed that lymphocyte counts decreased between every 2-week challenge-exposure period for groups-3 and -4 calves. A transient depression of blood lymphocyte (BL) responses to phytohemagglutinin (PHA), a T-cell mitogen, was observed over the first 8 weeks in the infected calves. Increases in BL responses to OAG were also observed. Differences were not observed in BL responses to pokeweed mitogen, a T- and B-cell mitogen. Blood lymphocyte responses to PHA in group-3 calves were low following the initial challenge exposure with OAG. The sensitized calf lymphocytes did not have suppressive activity on the response of control calf lymphocytes to PHA. Differences were not observed in lymphocyte responses to PHA in a suppressive assay done on abomasal lymph node lymphocytes. Increases in abomasal lymph node mass and lymphocyte responses to PHA, pokeweed mitogen, and OAG were observed in all sensitized calves. Histologic examination of abomasal lymph node sections from challenge-exposed calves revealed increased mitotic activity in germinal centers. Plasma pepsinogen values in groups 3 and 4 increased between each challenge exposure, which further suggested that type-1 hypersensitivity reactions had occurred in the abomasal mucosa, resulting in increased permeability and leakage of macromolecules.

Possible immunomodulation by low-level infection with Ostertagia ostertagi was studied in 4-month-old calves. Six groups of 4 calves each were subjected to the following regimes: group 1--nonparasitized controls; group 2--nonparasitized, but challenge exposed at day 64 with Brucella abortus strain 19 vaccine (BA) and at day 78 with IV administration of a soluble third-stage larval (L3) antigen preparation of O. ostertagi (OAG); group 3--nonparasitized, but challenge exposed at day 78 with 75 X 10(3) L3 of O ostertagi; group 4--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi; group 5--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi, then challenge exposed on day 64 with BA and on day 78 with IV inoculation of OAG; and group 6--continuously parasitized by weekly dosing with 30 X 10(3) L3 of O ostertagi, then challenge exposed on day 78 with 75 X 10(3) L3 of O ostertagi. Over the initial 10 weeks of the study, nonparasitized calves, (groups 1, 2, and 3) had higher body weight, blood lymphocyte (BL) response to phytohemagglutinin (PHA), and significantly (P less than 0.05) higher feed consumption and lymphocyte numbers, whereas parasitized calves (groups 4, 5, and 6) had higher BL responses to pokeweed mitogen (PWM) and significantly (P less than 0.05) higher neutrophil and eosinophil numbers, plasma pepsinogen (PP) values, and BL response to OAG. During the challenge-exposure period (weeks 10 through 13), group-5 calves had significantly (P less than 0.05) higher eosinophil numbers and PP values for week 11 (BA challenge exposure) and for week 13 (OAG challenge exposure) than did group-2 calves, but differences were not observed in BL responses to PHA, PWM, and OAG. Oral L3 challenge exposure at week 13 induced significantly (P less than 0.05) lower lymphocyte numbers, higher eosinophil numbers (P less than 0.05), and higher PP values, but lower BL response to PHA, PWM, and OAG in group-6, compared with group-3 calves. In continuously parasitized calves, comparison of IV OAG challenge exposure with oral L3 challenge exposure indicated that group-6 (L3) calves has significantly lower (P less than 0.05) lymphocyte numbers and higher PP values than did group-5 (OAG) calves. Results of ELISA revealed significantly (P less than 0.05) higher antibody titer to OAG in parasitized calves, compared with nonparasitized calves. Abomasal mucosal pathologic changes were most severe in the continuously parasitized calves. Calves of groups 4, 5, and 6 had thicker mucosae (edema), significantly (P less than 0.05) higher eosinophil numbers, and higher globule leukocyte and mast cell numbers in the fundic and pyloric regions than did calves of groups 1, 2, and 3. Calves of groups 4, 5, and 6 also had significantly (P less than 0.05) larger abomasal lymph node masses than did nonparasitized calves. In group-1 calves, nodes had the lowest mass. Differences were not observed among groups for lymphocyte responses to proliferative and suppressive assays performed on the abomasal lymph node lymphocytes.

Although cats are less susceptible to infection with Dirofilaria immitis than are dogs, the possibility of severe consequences from infection or adulticidal treatment renders preventive treatment a desirable alternative in endemic areas. To evaluate the efficacy of milbemycin oxime as a chemoprophylactic agent in cats, 48 cats were inoculated with infective D immitis larvae. Single oral treatment with 2.3 mg of milbemycin oxime (0.5 to 0.9 mg/kg of body weight) at 30 or 60 days after inoculation with infective larvae gave strong but incomplete protection. Treatment at 60, as well as 90, days after inoculation with infective larvae was completely effective in preventing development of infection. A control group of inoculated, but untreated, cats was monitored biweekly for hematologic changes and for changes in parasite-specific serum antigen and antibody concentrations. Pronounced increases in total leukocyte counts and eosinophil numbers were associated with the estimated time of in vivo molting from fourth- to fifth-stage larvae. Antibody reactivity correlated with infection status, but serum antigen concentrations through 161 days after inoculation were undetectable.

Inoculation of swine with a sylvatic isolate of Trichinella spiralis, designated T s nativa, resulted in low numbers of muscle larvae, compared with muscle larvae accumulation in swine inoculated with a pig type of T s spiralis. Despite low infectivity of T s nativa for swine, primary inoculation resulted in high levels of immunity against challenge infection with T s spiralis. This immunity was expressed in accelerated expulsion of challenge adults from the intestine and reduced numbers of muscle larvae. Pigs inoculated with T s nativa developed cellular and humoral responses similar to those in pigs inoculated with T s spiralis. However, in immunoblots, sera from pigs inoculated with T s nativa recognized additional proteins in muscle larvae excretory-secretory (ES) products, compared with sera from pigs inoculated with T s spiralis. Active immunization of pigs with ES products from T s nativa resulted in numerically higher, but not significantly different levels of immunity, compared with pigs immunized with ES from T s spiralis. The highest levels of immunity were obtained in pigs immunized with a T s spiralis newborn larval extract. The combination of ES products and newborn larval extract did not result in additive levels of immunity. These results indicate that the major immune effector response to Trichinella sp in pigs is against the newborn larvae, regardless of the genetic type of Trichinella sp.

Musculature from 198 Canadian cattle with suspected lesions of eosinophilic myositis were examined histologically and by pepsin digestion. Sera from 51 of the 198 animals were also examined by enzyme-linked immunosorbent assay (ELISA) for anti-Trichinella antibodies. Viable larvae of Trichinella were not recovered from any of the cattle but one animal from Ontario tested positive for anti-Trichinella antibodies. Histologically, focal and/or diffuse eosinophilic myositis lesions were observed in 149 (75.2%) of the animals studied. Other conditions identified were sarcocystiosis, abscesses, cysticercosis, steatosis, fibrosis, granuloma, lymphosarcoma and necrosis. Sarcocystiosis was identified in 105 of the 198 animals in both normal and affected musculature. The study indicates that trichinosis is not a primary cause of eosinophilic myositis in cattle.