Zinc Sulfate Flotation Technique Research Articles

Comparative performance evaluation of four different methods for diagnosing Giardia infection in dogs and zoonotic assemblages’ identification

Giardia duodenalis (syn. G. intestinalis or G. lamblia) is a parasitic protozoan that infects the upper intestinal tract of a broad range of hosts, including humans and domestic animals. Thus, it has raised concerns about the public health risk due to companion animals. Recently, with the improvement of living standards and increasing contacts between pets and humans, the zoonotic transmission of Giardia has dramatically increased. From a genetic point of view, G. duodenalis should be viewed as a complex species that includes eight different species-specific genetic assemblages. The laboratory diagnosis is mainly based on the finding of microscopic cysts in stool samples by coprological examination. Other methods include the detection of antigens, immunoassays or PCR protocols, which allow the identification of Giardia assemblages. The study aimed to compare the performance of Direct Fluorescence Antibody test (DFA), zinc sulfate flotation technique (ZnSO4), rapid diagnostic test (RDT), end-point PCR amplification (PCR) for the detection of Giardia and to identify the concerning assemblages in a canine population from Central Italy. Direct fluorescence antibody test is the reference standard for laboratory diagnosis of Giardia in fecal samples from dogs, despite the microscopic examination after flotation remains the most useful method in many veterinary diagnostic centers. The present findings demonstrate the high performance of DFA and ZnSO4 in detecting Giardia, while RDT may be useful as alternative or complementary method to the DFA and ZnSO4. PCR performance was low, but it allowed determining Giardia B zoonotic assemblage in 25% of the PCR-positive specimens (15 out of 60), while the remaining PCR-positive isolates belonged to the dog-specific assemblage C. The 26% prevalence of G. duodenalis detected by DFA in owned dogs and the identification of potentially zoonotic assemblages underline the potential risk for public health and indicate frequent cross-species transmission of the parasite between humans and dogs.

Efficacy of a single dose of nitazoxanide in dogs naturally infected with Giardia duodenalis

Giardia duodenalis is a protozoan parasite that infects many mammals, including dogs and cats. This waterborne and foodborne zoonosis is a major problem in one health. Treatment can be challenging because of long regimens and drug resistance. The objective of this study was to evaluate the efficacy of single-dose nitazoxanide (NTZ) for dogs naturally infected by Giardia duodenalis. Although widely used in humans, pharmacological safety is incipient, since the approval of the safe use of nitaxozanide for dogs is not a consensus in the world. Fifty dogs diagnosed with G. duodenalis by zinc sulfate flotation technique (Faust method) and cysts detection by light microscopy. Half of the animals received a dose of 50 mg/kg of NTZ and the other half received 3 doses of 50 mg/kg of fenbendazole (FBZ), both orally. One week after treatment, new fecal exams were done to prove the effectiveness. Of the animals treated with NTZ, 84% were negative for the protozoan, while 76% of the animals treated with FBZ were negative, no significant difference was identified. Side effects such as vomiting and hyporexia were manageable in NTZ treatment and no changes in laboratory tests showed hepatic or renal impairment. We conclude that the use of NTZ in a single dose of 50 mg/kg is effective for canine giardiasis, constituting an option to be considered for dogs with relapses, poor response to conventional drugs and to facilitate administration regimens.

Diagnóstico de parasitosis gastrointestinal en ganado vacuno de razas carniceras con diferentes técnicas coproparasitológicas

Gastrointestinal parasites in production cattle are one of the most important health problems worldwide. These nematodes cause gastroenteric problems that are clinically characterized by diarrhoea, weakness, bleeding and dehydration. Within the gastrointestinal parasites caused by nematodes in cattle, the following families stand out: Trichuridae, Trichostrongylidae, Ancylostomidae, Ascaridae and Strongyloididae. The purpose of this research was to determine the efficacy of the different qualitative and quantitative coproparasitological techniques for the detection of gastrointestinal nematodes in cattle. For this study, 250 samples of beef breed cows were used, divided into different groups, for the application of qualitative and quantitative coproparasitological techniques, which were specifically chosen taking into account inclusion and exclusion criteria for each animal. The results delivered by this study indicated that the highest percentage in the identification of parasitic infective states was through qualitative coproparasitological techniques, focused mainly on zinc and magnesium sulfate flotation techniques with 50%.

Comparative study of the intestinal parasitism profiles between communities across the 5 municipalities of the Barranquilla metropolitan area, Colombia.

Objectives The aim of this study was to compare the rate of parasitism and intestinal parasitism profiles of children who live in relatively proximal communities across the 5 municipalities of the Barranquilla metropolitan area, Colombia.MethodsIn total, 986 fecal samples from children aged 1 to 10 were analyzed using a direct method (physiological saline and lugol) and the zinc sulfate flotation technique. A comparative analysis of the parasitism profiles between sampling locations (7 schools and 3 health centers providing growth and development services) was conducted using principal component analysis (PCA). The presence of Taenia solium antibodies was evaluated by the enzyme-linked immunosorbent assay method in 269 serum samples from the same group of children.ResultsThe overall prevalence of intestinal parasitism was 57.6% (range, 42.1%–77.6%) across the sampling areas. The prevalence of helminthiasis was between 4.1% and 23.7%, and that of intestinal protozoa was between 38.2% and 73.5%. PCA showed that the parasite profiles of each sampling location shared no common characteristics. A total of 3.0% of the serum samples were positive for T. solium antibodies.ConclusionThe intestinal parasitism profiles between relatively proximal sampling locations with similar geographic conditions were vastly different, indicating the need to study each small ecological niche on a localized scale to develop more cost-effective interventions for controlling intestinal parasitism.

Occurrence of Soil-transmitted Helminths from Selected Dumpsites and Farmlands in Calabar, Nigeria

Aims: The present study investigated the prevalence and intensity of soil-transmitted helminth contamination in dumpsite and farmland soils in Calabar, Cross River State, Nigeria.
 Methodology: Soil samples were randomly collected from selected dumpsites and farmlands from July to December 2019. 200 soil samples (100 samples each from dumpsites and farmland) were collected. Soil samples were analysed using Zinc sulphate flotation technique whereas soil nematode extraction for hookworm and Strongyloides larvae was carried out using the modified Baermann technique.
 Results: Of the 200 soil samples examined, 131 (65.5%) were positive for ova/larvae of one or more parasites. Dumpsite soils were highly contaminated with ova/larvae of soil-transmitted helminths than farmland soils with a prevalence of 79% (n=79) and 52% (n=52) respectively (P=.02). Farmlands had the highest mean intensity (6.75±1.88) of contamination with ova/larvae of soil-transmitted helminths compared to dumpsite soils (1.68±0.14). Ascaris lumbricoides recorded the highest occurrence (35.5%) (P=.003) in soil samples examined. A. lumbricoides (40%) and Trichuris trichiura (6%) contamination was higher in dumpsite soils, while Strongyloides stercoralis larvae (34%) and hookworm (10%) contamination was higher in farmland soils. Dumpsite soils recorded the highest number of parasites (84%) in the wet season, while farmland soils recorded the highest number of parasites (92%) in the dry season (P=.11). Generally, parasitic ova/larvae were more prevalent in the dry season (91%) than in the wet season (73%) (P=.33). S. stercoralis (33%) was more prevalent in the wet season followed while A. lumbricoides (43%) recorded highest occurrence in the dry season.
 Conclusion: This study revealed the potential health risk of contracting soil-transmitted helminth parasites in soils around farmlands and dumpsites in Calabar, Nigeria. It is therefore important that a combination of sanitation and health education be put in place for effective control of soil-transmitted helminths.

Comparison of the Detection of Toxocara Spp. in the Soils of Public Parks of Ahvaz (Southwest of Iran) by PCR and Loop-Mediated Isothermal Amplification (LAMP).

The infections caused by Toxocara spp. are considered as one of the most important zoonotic diseases in the world, especially in developing countries. Human toxocariasis, particularly in children, is acquired by playing in public parks. Hence, the aim of the current study was to detect Toxocara spp. in the soils of public parks of the city of Ahvaz, southwest of Iran, using the PCR and loop-mediated isothermal amplification (LAMP) methods. In this descriptive cross-sectional study, 260 soil samples were randomly collected from the different public parks of the city of Ahvaz. After performing zinc sulfate (ZnSO4) flotation technique, the DNA samples were extracted from the isolated Toxocara spp. eggs. Lastly, the extracted DNA was used for PCR and LAMP-based molecular detection. Out of 260 specimens, 57 (21.9%) samples were found positive for Toxocara spp., using the PCR method, out of that 38 (14.6%) samples were positive for T. canis and 19 (7.3%) samples were positive for T. cati. Also, out of 260 specimens, 81 (31.1%) cases were positive for Toxocara species, using the LAMP method, among them 51 (19.6%) samples were found positive for T. canis and 30 (11.5%) samples were positive for T. cati. Kappa (κ) coefficient between PCR and LAMP showed a strong agreement (0.766, P-value=0.002). The obtained data showed a relatively high outbreak of Toxocara spp. in the public parks' soils of the city, using the PCR and LAMP methods. Since the parasite can cause human toxocariasis, particularly in children; thus, the health authorities of the city of Ahvaz and other similar cities, especially in developing countries, must pay more attention to the hygiene of the public parks' soils.

Intestinal helminths in Iberian wolves (Canis lupus signatus) from Northwest Spain

Background: We present a study about helminth parasites in wolf (Canis lupus signatus) from Sierra de la Culebra, a protected area in the Northwest of Spain, where is the largest population of wolves of the Spanish territory and one of the largest in Western Europe. Materials and Methods: To this aim, 93 fecal samples were collected during May and June of 2013 using 33% zinc sulphate flotation technique and classified based on their morphology, color, structure and size. Results: Parasites were present in 66.67% of the samples and classified as Eucoleus aerophilus (50.54%), Strongyloides sp. (27%), Ancylostomidae gen. sp. (19.35%), Toxocara Canis (10.75%), Taeniidae gen. sp. (9.68%), Trichuris vulpis (9.68%) and Toxascaris leonina (2.15%). Their distributions were very heterogeneous with the highest prevalence being in Northwest Spain. These differences found can be attributed to local environmental factors (ambient temperature, humidity) as well as animal feeding and social behavior. Conclusion: A wide helminthofauna is observed in the studied wolves, similar to other studies carried out in Europe (Estonia, Finland, Italy, Latvia, Poland, Portugal, Spain and Sweden). In addition, this study constitutes the first description of the presence of Strongyloides sp. in Iberian wolf in Spain.

Assessment of the diagnostic performance of four methods for the detection of Giardia duodenalis in fecal samples from human, canine and feline carriers

Enteric parasitic diseases including giardiasis are of public health concern. Different methods are available for the diagnosis of this parasitic infection in fecal samples such as the identification of protozoan cysts and trophozoites by light microscopy, detection of specific antigens by ELISA, and amplification of DNA fragments by PCR. The present study aimed at assessing the performance of four laboratory tests for the detection of Giardia duodenalis in fecal specimens from three different host species with a previous diagnosis of giardiasis; canine, feline and human patients provided new stool samples to be retested for Giardia before initiating treatment with antiprotozoal drugs. For this purpose, triplicate fecal specimens from 54 humans, 24 dogs and 18 cats living in the city of Niterói, RJ, southeast Brazil, were analysed by light microscopy, ELISA, immunochromatography, and nested PCR. The centrifugal-flotation method detected Giardia cysts in 89.6% (86/96) of the fecal samples. The protozoan parasite was detected via immunochromatography in 87.5% (84/96) of these samples. Giardia was detected by ELISA in 69.8% (67/96) of the stool specimens from carriers with a previous diagnosis of Giardia infection. Giardia was detected by PCR in only 39.6% (38/96) of the fecal specimens. Based on these findings, we suggest that, among the four assays that were used in this study, the zinc sulphate flotation technique (Faust et al., 1939) is the best diagnostic assay in terms of sensitivity and specificity to detect G. duodenalis on serially collected samples from dogs, cats and humans.

A Comparative Study of Concentration Techniques for Detection of Intestinal Parasitic Infections – to Evaluate the Prevalence And to Identify A Better Method of Concentration Technique At A Tribal Tertiary Care Hospital

Parasitic infection caused by helminths and protozoa are the major cause of human disease in most countries of tropical region. It is estimated that about 3.5 billion people are infected with intestinal parasites of whom 450 million are ill. The prevalence of intestinal parasitic infection varies not only geographically but also in different region in the same country. The present study is undertaken to determine the rate of prevalence of intestinal parasitic infection among all age group of people in this tribal area and to determine the best concentration technique to identify maximum number of intestinal parasites. Material & Methods: A total of 836 stools samples were collected from patients with symptoms of parasitic infestation and the same were subjected to (1) Gross examination (2) Direct microscopic examination by using saline and iodine preparation and (3) modified Ziehl Neelson staining after fixing with methanol (4) different concentration technique viz.. (a) Brine concentration flotation technique (b) Zinc sulphate flotation technique (c) Formal ether concentration sedimentation technique (d) Merthiolate iodine formalin sedimentation technique. Results: Out of total 836 stools samples the detection rate by various methods was 286(34.2%) for ova and cysts of protozoa , coccidian and helminths. Compared to females (29.75%), males (38%) were more affected. The direct smear saline mount could only detect 36% while the maximum detection 66% of intestinal parasite was after Formalin ether concentrated sedimentation technique. Among the intestinal protozoa, Entamoeba histolytica (53.49%) was the most common followed by Giardia cysts (8.04%) . Coccidian parasites like cryptosporidium parvum and isospora beli were detected in the HIV infected patient only. Ascaris lumbricoides (16.43%) followed by ancylostoma duodenele (9.09%) were the common helminthic infections.

Prevalence of Giardia Cysts in Household Dog Faeces within Zaria Metropolis, Kaduna State, Nigeria and its Public Health Significance

Giardiasis is a major cause of diarrhoea in both humans and animals. In developing countries such as Nigeria, the disease has important Veterinary and public health consequences. This study determined the prevalence of Giardia cysts in dog faeces in Zaria, Kaduna State, Nigeria and its Public Health Significance. Four hundred and two (402) dog faecal samples were collected and examined for Giardia cysts using zinc sulphate flotation technique. Of the 402 dog faecal samples examined, 70 (17.4%) were positive for Giardia cysts. Giardia cysts were higher in male dogs (18.9%) than in females (15.6%). Higher prevalence of Giardia cysts were observed in puppies ( 6months) (16.7%). Also higher prevalence of Giardia cysts was observed in cross/exotic breeds (20.9%) as compared to local breeds (16.4%). There was no statistical association between the prevalence of Giardia cysts and dogs with diarrhoea, sex, age and breed (P>0.05). There was a higher prevalence (15.7%) of Giardia cysts in strayed dogs than in confined dogs (14.6%). There was statistical significant association (P=0.01) between Giardia cysts and straying of dogs. Purpose of keeping dogs as Pet (OR: 0.36; 95% C I on OR 0.05) This research provides useful information on the prevalence of Giardia cysts in household dogs, which may help regulatory bodies and Government agencies in making policies in controlling Giardiasis in the study area.

Efficacy of some laboratory methods in detecting giardia lamblia and cryptosporidium parvumin stool samples

Background: Giardia duodenalis and Cryptosporidium parvum are the most prevalent intestinal parasites of human. It also infects a wide range of mammals .Two genotype of G.duodenalis (A and B) were commonly reported among humans with different frequency of distribution in different geographical locations. Methods :total of 434 stool samples were collected from peoples in kikrkuk city during October 2012toAugust 2013. Zinc sulphate flotation technique was applied on 226 positive stool, serological methods involve Giardia ELISA-corpo antigen, Direct fluorescent assay (DFA), and lateral immune-chromatography assay(Triage panel) .Extractions of Giardia genome DNA from stool samples were performed using QIAamp Stool Mini kit with a modified protocol. PCR- one step procedure was used to amplify a fragment of Giardia lamblia genome using k725 gene locus,(Mixture primers of human A and B assemblages) Results:The overall rate of intestinal parasitic infection was 52.07%,Giardia lamblia rate was 24.65%.Common isolated parasites were Cryptosporidium parvum ,Blastocystishominis, other intestinal protozoan parasites and nematode helminthes:7.60 & 5.76 %,7.37 and 6.68 % respectively. Sensitivity and specificity of PCR method and direct microscopy were higher than other four methods used for detecting giardiasis. Triage panel method exert high rate of giardiasis than revealing of Cryptosporidium and Entamoeba histolytica. From the application of five methods for Cryptosporidium diagnosis, DFA and modified Ziehl-Neelsen(MZN) methods show high sensitivity and specificity than other three methods. Application of PCR single step using mixture primers assemblages A and B, show high rate of sensitivity than other methods in detecting giardiasis.Amplified Giardia genome length extended from 220 to 750 bps with mean of 437.56 bps. Conclusions: PCR assay targeting K725 gene locus is a sensitive tool and discriminates mixed genotypes of G.lamblia. DFA and MZN are sensitive tools for detecting Cryptosporidium parvum in stool samples

Freqüência de Giardia spp. por duas técnicas de diagnóstico em fezes de cães

One hundred fecal samples from male and female dogs of several ages and breeds were collected in kennels of Uberlândia in Minas Gerais, Brazil. These samples were analyzed to determine the frequency of Giardia spp. using two different diagnostic methods: zinc sulfate flotation technique and merthiolate-iodine-formaldehyde concentration (MIFC). The frequency of giardiasis was 41%. Dogs, which were less than 12 months of age, were the most parasitized (68.4%). No difference between male and female frequency of giardiasis (31.4% and 46.1%, respectively) was observed. MIFC detected 38% of positive samples and zinc sulfate flotation technique 29%. Giardia spp. is present in dogs of Uberlândia's kennels in a high frequency.

Parasitologic analyses of the sifaka (Propithecus verreauxi verreauxi) at Beza Mahafaly, Madagascar.

A cross-sectional parasitologic survey of a population of wild sifaka (Propithecus verreauxi verreauxi) was conducted at the Beza Mahafaly Special Reserve in southwest Madagascar. Ninety fecal samples were collected from thirty 1- to 30-yr-old male and female sifakas, and the formalin-preserved and polyvinyl alcohol-preserved specimens were examined using the zinc sulfate flotation and formalin-ethyl acetate sedimentation techniques. No intestinal parasites were recovered, possibly because the sifakas are arboreal in a dry, riverine habitat and lack human contact. Low rates of parasitic infection may have contributed to the evolution of later age at first reproduction and longer reproductive lifespan, for body mass, in Propithecus compared with other placental mammals.

Efficacy of a combination febantel-praziquantel-pyrantel product, with or without vaccination with a commercial Giardia vaccine, for treatment of dogs with naturally occurring giardiasis.

To determine efficacy of treatment with a combination febantel-praziquantel-pyrantel product, with or without vaccination with a commercial Giardia vaccine, in dogs with naturally occurring giardiasis. Prospective trial. 16 Beagles naturally infected with Giardia duodenalis. During phase 1, 6 dogs were treated with the parasiticide for 3 days (4 were also vaccinated). Four weeks later, all 6 dogs were treated with the parasiticide again for 5 days and were bathed and moved to clean cages after the last treatment (phase 2). Nine dogs were treated with the parasiticide for 3 (n = 4) or 5 (5) days and bathed and moved to clean cages after the last treatment (phase 3). Fecal samples were collected twice weekly for 24 days after treatment and tested for cysts with a quantitative zinc sulfate flotation technique and for Giardia antigen with an immunoassay. Dogs in phase 1 were all shedding cysts again by day 24. In phase 2, only 1 dog shed cysts after treatment, and shedding was transient (day 17). In phase 3, neither cysts nor antigen was detected in fecal samples from 2 of 4 dogs treated for 3 days and 4 of 5 dogs treated for 5 days. In 18 of 57 (31.6%) fecal samples, cysts were seen, but results of the immunoassay were negative. Results suggest that when a combination febantel-praziquantel-pyrantel product is used to treat dogs with giardiasis, bathing and changing the environment after treatment may be more important in preventing recurrence than duration of treatment.

Larvicidal Activity of Albendazole against Necator americanus in Human Volunteers

This study evaluated the efficacy and tolerance of a single oral 400-mg dose of albendazole on Necator americanus larvae, and compared its efficacy when administered between meals or with a meal. Twenty-nine healthy and hookworm-free male volunteers were exposed on the forearm to approximately 45 8-day-old N. americanus larvae. All subjects developed discrete maculopapular eruptions at the site of larval application. Following a random double-blind study design, each subject received at the end of the 6th post-infection day either the investigational drug or a placebo as follows: Group I (n = 8)-placebo; Group II (n = 11)-400 mg albendazole with a meal; Group III (n = 10)-400 mg albendazole 3 or more hours after or before a meal. On day 56 post-infection, the stools of all subjects who received placebo were positive for N. americanus eggs (by zinc sulfate flotation technique), compared with 48% positivity (10/21) in those who received albendazole (P = 0.01). By day 63 post-infection, an additional three subjects in the treatment group became positive, for an overall 62% rate of positivity (13/21), i.e., albendazole prevented patent infection in 38%. Administration of albendazole with a meal did not alter drug efficacy. In those subjects in whom patent infections were not prevented, egg output was one-fourth that of the placebo group. There was no difference in viability of eggs appearing in feces of treated and untreated subjects as judged by larval development in Harada-Mori cultures. Our data indicate that albendazole is active against pre-intestinal stages of N. americanus in human infections.

Prevalence Of Intestinal Parasites In Korea

A survey of intestinal parasites infection among Korean people has been carried out during July 1969 to December 1970. A total of 2,250 stool specimens (male 1,101, female 1,146) was collected from all the provinces and Seoul city in Korea. The specimens were examined routinely by direct fecal smear, zinc sulfate flotation and formalin-ether sedimentation techniques. The results are summarized as follows: 1. Of 2,250 specimens examined, l,803(80.l %) were positive for intestinal parasites. 2. The positive rates of intestinal helminths were 1,644(73.1 %) among 2,250; Ascaris lumbricoides 46.0 %, Trichocephalus trichiurus 46.8 percent, hookworm 6.8 %, Trichostrongylus orientalis 7.0 percent, Clonorchis sinensis 12.1 percent, Enterobius vermicularis 1.6 %, Hymenolepis nana 0.7 percent, Taenia species 0.3 %, Metagonimus yokogawai 0.04 percent, Fasciolidae 0.04 % and one case of lung fluke Paragonimu westermani. 3. The positive rstes of intestinal protozoa were 786(34.9 %); Entamoeba histolytica 6.4 %, Entamoeba coli 20.5 percent, Endolimax nana 10.0 %, Giardia lamblia 5.1 %, Trichomonas hominis 1.1 percent, Chilomastix mesnili 0.5 percent, Iodamoeba butschlii 0.6 percent, Enteromonas hominis 0.7 percent, Dientamoeba fragilis 0.1 % and one case of Isospora hominis. 4. Sexual distribution of helminths and protozoan infections showed higher rate in female than that of male, except C. sinensis, H. nana, Taenia species or G. lamblia. 5. Infections of T. trichiurus, hookworm, T. orientalis, C. sinensis, Taenia species, E. histolytica, E. coli and E. nana increased with age. Conversely, H. nana and G. lamblia infections were more predominent in younger ages.

Anatrichosomiasis in African Monkeys

Approximately 29% of 298 African monkeys belonging to 5 species (Erythrocebus patas, Cercopithecus talapoin, C. aethiops, Cercocebus galeritus, and Papio sp.) obtained from various parts of Africa were found to be infected with species of Anatrichosoma. The adult worms were found in the nasal epithelium. The embryonated eggs which accumulate on the epithelial surface were easily removed with a cotton-tipped applicator stick, nasopharyngeal swab, or similar implement. Eggs were rarely found in the feces by routine diagnostic methods. Swabbing of the nasal mucosa was found to be the most reliable and accurate procedure for diagnosis of infections in living animals. Although specific determinations were not made, it appeared that the parasites from the African monkeys were different from A. cutaneum and A. cynamolgi described previously from Asian monkeys. The anatrichosomes are relatively rare and poorly known trichuroids which, to date, have been found in the skin and nasal mucosa of Asian monkeys (Swift et al., 1922; Smith and Chitwood, 1954; Chitwood and Smith, 1958; Allen, 1960) and on two occasions in man (Morishita and Tani, 1960; Le-Van-Hoa et al., 1963). Infections have been recognized more frequently as a result of recovery of adult worms at necropsy than from finding the eggs of the parasite. The latter have been found in scrapings of the nasal mucosa and occasionally in feces (Allen, 1960; Reardon and Rininger, 1968). Reports concerned with this parasite are so few that our knowledge of the species, their host range, and geographical distribution is very limited. Recently, in the course of histological examination of nasal tissues from an African patas monkey (Erythrocebus patas), Dr. Herman Seibold of the Pathology Laboratories, Delta Regional Primate Research Center, observed sections of a nematode in the mucosa and referred the slides to the author for identification. Examination of the sections of worms revealed that they were trichuroids. Their location and the morphology of the fully embryonated eggs found in the tissues indicated that they were a species of Anatrichosoma. Examination of intact worms subsequently recovered from animals at necropsy confirmed the tentative diagReceived for publication 14 January 1970. * Presented at the Forty-fourth Annual Meeting of the American Society of Parasitologists in Washington, D. C. 3-7 November 1969. This investigation was supported by U. S. Public Health Service grants FR 00164, DRFR and Al 06828, NIAID, NIH. nosis. Because there are no existing reports of anatrichosomes in African primates and because routine stool examinations in the past have failed to demonstrate the presence of the parasite in colony animals except rarely, studies were undertaken to ascertain the prevalence of this parasite in African primates and to determine the most suitable method for its diagnosis. MATERIALS AND METHODS The monkeys utilized in the study were maintained in the Delta Primate Center's animal colony or, in some cases, at other institutions. The nasal passages of each animal were swabbed with a dampened, cotton-tipped applicator stick or commercially prepared, sterile, nasopharyngeal swab (Calgiswab?), or rectal swab (SWUBE?), depending on the size of the nostrils. The swabs were examined under a binocular dissecting microscope with incident light to determine whether or not eggs were present. Stool examinations were made by direct-smear, formalin-ether, and zinc sulfate flotation techniques. At necropsy, portions of the nose and upper lip were removed from infected monkeys and fixed in Bouin's solution or 10% formalin. These tissues were processed by routine methods, sectioned at 7 ,i, and stained with hematoxylin and eosin. Worms removed from the tissues in toto were fixed in glacial acetic acid, transferred to 70% alcohol to which glycerin was added gradually, and were brought to pure glycerin by evaporation for microscopic study. RESULTS AND DISCUSSION Histological examination of tissues from infected animals revealed that adult worms usually are located in that portion of the nasal cavity lined with stratified squamous epithelium (Fig. 1). The female worms make extensive burrows in the epithelium as they wander through the tissues, depositing eggs in their wake. The eggs remain in these burrows or

Helminth Survey of Dogs and Cats in New Jersey

Single fecal examinations, using the zinc sulfate flotation technique, were performed on 4,217 animals (2,737 dogs and 1,480 cats) and 3,730 helminth infections were revealed. Of these animals, 685 dogs and 318 cats were treated and necropsied, thus uncovering 584 additional infections not found by flotation. About 55% of the additional infections were tapeworms, and the remaining 45% were nematodes, of which 22% were light infections, 17% were immature, and 6% consisted of male worms only. In recent years there have been a number of surveys of helminths of dogs and cats, including one from this laboratory (Burrows and Lillis, 1960). Since many surveys are based on single fecal examinations and since additional species are often found in those animals that are necropsied, it appeared that many surveys probably fail to reveal a fair percentage of infections harbored. To determine this, a detailed study was made of records of stool examinations, treatment results, and necropsies of dogs and cats used in this laboratory from 1 April 1960, the end period of the previous report (Burrows and Lillis, 1960), through 31 October 1966. MATERIALS AND METHODS The animals were strays, supplied by a regular dealer who obtained them from central New Jersey, the same general area as in earlier reports of other infections (Lillis and Burrows, 1964; Lillis, 1964; Burrows and Lillis, 1965, 1967). The animals were housed in individual cages and remained at the laboratory only a few days to a few weeks, so there was no opportunity to acquire an infection while at the laboratory. Stool examinations were performed shortly after receipt of the animals, using the zinc sulfate flotation technique (sp. gr. 1.2). The strong solution was used because it will float heavier eggs, such as Taenia (Burrows, 1965). All helminth eggs and larvae found by flotation were identified and recorded. Data from the necropsy of dogs and cats were obtained during routine anthelmintic screening trials. These animals were known to be infected with certain parasites, as found on flotation, and were used in chemotherapeutic trials of experimental compounds. A stainless steel pan was placed in the bottom of each cage and all feces passed were collected and examined for worms Received for publication 10 April 1967. * Present address: CIBA Research Farm, Three Bridges, New Jersey 08887. present. The specimens were washed in a 40-mesh sieve and the sieve contents examined, a little at a time, in a black-bottomed pan for worms passed. At necropsy, the small intestine was examined carefully for worms remaining. The worm burden of an animal was the sum of the worms passed plus those remaining at necropsy. Since numerous animals were given compounds that did have anthelmintic activity, many worms passed out in a disintegrated condition, and sex, species, and degree of maturity could not always be determined. For some animals, no worms could be recovered at all, as a result of disintegration and in this case, the intensity of the infection was considered light, and in the range of from one to 10 worms. Infections of hookworm and whipworm in dogs and hookworm and ascarids in cats, that fell in various ranges, were counted to demonstrate the intensity of the worm burdens in the necropsied animals.

Trematodes of New Jersey Dogs and Cats

During the period from 1959 to 1964 the following nine species of trematodes were found in New Jersey cats and dogs: Eurytrema procyonis, Parametorchis complexus, Phagicola longus, Cryptocotyle concava, C. lingua, Echinochasmus schwartzi, Paragonimus kellicotti, Alaria canis, and A. marcianae. E. schwartzi, and A. marcianae are redescribed. Trematodes are reported relatively infrequently from dogs and cats in North America, whereas nematode and cestode infections are rather common. During the period from 1959 to 1964 we found 23 fluke infections in animals examined in our laboratory. We probably missed others, because we used only the zinc sulfate flotation technique in stool examinations in our search for nematode infections, and operculated eggs fail to float in many cases. The dogs and cats came from central New Jersey, particularly Monmouth and Burlington counties. We cannot determine the exact locality of any specific animal, for the dealer who supplies us collects strays throughout the area. Living flukes from these animals were relaxed in menthol solution prior to fixation, with the result that relatively few were distorted. Permanent preparations of a number of these flukes were deposited in the USNM Helm. Coll., Beltsville, Maryland, and their accession numbers are given below. The dates after the accession numbers refer to the dates the flukes

The Effect of Bile Flow on Giardia duodenalis Race Simoni in the Intestine of a Laboratory Strain of Rattus norvegicus

The rat was used to determine the effect of bile on the survival of Giardia duodenalis race simoni. Using surgical techniques, the flow of bile into the intestines of laboratory rats known to be infected with Giardia was eliminated. Approximately 24 hr after surgery, several locations in the intestines of the altered rats were examined for trophozoites. From the results obtained, it appears bile in the intestine is necessary for survival of Giardia in the laboratory rat. In the past, certain investigators have implied Giardia was either a parasite of the gall bladder and bile ducts or it caused disease of the liver, gall bladder, and bile ducts (Kantor, 1923; Smithies, 1928; De Muro, 1939; Grott, 1939; Gondard, 1952). Others (Goia et al., 1961; Mandoul, 1939; and Cain and Sikorav, 1938) did not believe Giardia was either a parasite of the hepatic system or it caused any disease related to the liver or its ducts. These references all pertained to human Giardia duodenalis race lamblial infections. Hegner and Eskridge (1939), checking for the parasite in a different host, examined the bile ducts of 123 rats and found no Giardia. More recently Karapetyan (1960) made a point of removing the bile by centrifugation from the material used as the inoculum in his in vitro studies on Giardia, so as not to interfere with his results. The only individuals who actually performed in vivo experiments using bile or bile salts were Hegner and Eskridge (1937). They stated sodium glycocholate favored the growth and multiplication of Giardia in rats, sodium Received for publication 25 February 1963. * Paper No. 5050, Scientific Journal Series, Minnesota Agricultural Experiment Station, St. Paul. This work partially supported by the University of Minnesota Graduate School Fund. 1The species designation used in this paper is of Filice (1952) in which he limits the number of species and assigns nontaxonomic race names to differentiate the various forms. taurocholate had no effect, and oleic acid was detrimental to the parasite. The present study was initiated to determine if bile had an effect on the rat Giardia, in vivo, as suggested by the work of Hegner and Eskridge (1937). Goodchild (1958), in his experiments on the effect of bile on Hymenolepis diminuta in the laboratory rat, concluded that bile contains a factor or factors apparently necessary for normal growth and maturation of adult H. diminuta in the rat host. MATERIALS AND METHODS Eighty-seven Sprague-Dawley rats were used in these experiments. They were fed Giardia duodenalis race simoni cysts ad lib. in the drinking water, the same method used in previous studies (Bemrick, 1962). The rats were used singly or in pairs at varying intervals following infection. In each individual, Giardia cysts were demonstrated by the zinc sulfate flotation technique before surgical procedures were initiated. Observations on Giardia-infected rats by Haiba and Williamson (1952) have indicated starvation induced elimination of Giardia from the intestinal tract. To avoid this, the rats were not starved prior to surgery. Rats positive for Giardia were surgically altered in one of seven ways: 1. The bile duct was ligated in two places with number 6-0 silk suture at the anterior one-third, and the duct was severed between the ligatures. 2. The bile duct was cannulated with Intramedic number 10 polyethylene tubing, exteriorizing the bile flow. The cannulae were inserted in the anterior one-third of the duct. The ligatures and cannulae were always placed in this area to try to prevent interference with the flow of pancreatic juices. The technique used was similar to