A total of 764 adult dogs were examined for microfilariae and adult worms of D immitis and 197 (25-8 per cent) were found to be infected. Direct blood examinations revealed only 47-2 per cent of the infected dogs whereas the blood serum examination detected 57-8 per cent of them. These results showed that the absence of circulating microfilariae could not be relied upon to be an accurate indication of the absence of patent heartworm infection. The average number of heartworms per dog was 5-5 with a range of one to 50.
Matched MeSH terms: Blood/parasitology; Dirofilariasis/parasitology; Dog Diseases/parasitology
Recurrent outbreaks of muscular sarcocystosis among tourists visiting islands in Malaysia have focused international attention on sarcocystosis, a disease once considered rare in humans. Sarcocystis species require two hosts, definitive and intermediate, to complete their life cycle. Humans can serve as definitive hosts, with intestinal sarcocystosis for two species acquired from eating undercooked meat: Sarcocystis hominis, from beef, and Sarcocystis suihominis, from pork. Symptoms such as nausea, stomachache, and diarrhea vary widely depending on the number of cysts ingested but appear more severe with pork than with beef. Humans serve as intermediate hosts for Sarcocystis nesbitti, a species with a reptilian definitive host, and possibly other unidentified species, acquired by ingesting sporocysts from feces-contaminated food or water and the environment; infections have an early phase of development in vascular endothelium, with illness that is difficult to diagnose; clinical signs include fever, headache, and myalgia. Subsequent development of intramuscular cysts is characterized by myositis. Presumptive diagnosis based on travel history to tropical regions, elevated serum enzyme levels, and eosinophilia is confirmed by finding sarcocysts in muscle biopsy specimens. There is no vaccine or confirmed effective antiparasitic drug for muscular sarcocystosis, but anti-inflammatory drugs may reduce symptoms. Prevention strategies are also discussed.
Both sexes of Brachiella malayensis n. sp. are described on the basis of specimens found in the nostrils of narrow-barred Spanish mackerel Scomberomorus commerson (Lacepède) collected off Besut, Malaysia. The female of this species closely resembles those of B. magna Kabata, 1968 and B. cybii Pillai, Prabha et Balaraman, 1982 but is distinguishable mainly by the body size and the proportions of the cephalosome, posterior processes and caudal rami. While examining the male, we noticed a systematic inconsistency in some lernaeopodid genera. The genus Brachiella Cuvier, 1830, represented by its type-species Brachiella thynni Cuvier, 1830, and two monotypic genera Charopinopsis Yamaguti, 1963 and Eobrachiella Ho et Do, 1984, represented by Charopinopsis quaternia (Wilson, 1935) and Eobrachiella elegans (Richiardi, 1880), respectively, share distinct synapomorphies in the embracing (vs. pinching) elongate male maxilliped and the female trunk with a pair of long, cylindrical ventroposterior processes (in addition to a pair of modified caudal rami), both of which are involved in their unique reproductive strategy. The latter two genera are herewith relegated to junior synonyms of Brachiella.
Matched MeSH terms: Fish Diseases/parasitology; Nasal Cavity/parasitology; Perciformes/parasitology*
Amorphophallus bufo is a rarely studied plant in Malaysian tropical rainforests. We measured the spectral reflectance of different developmental stages of A. bufo (seedlings, juveniles and adults), background soil/ debris and leaves from other neighboring plant species. Results show that the leaves of A. bufo seedling have a similar reflectance curve as the background soil and debris. Adults and juveniles of A. bufo are similar to other neighboring plants' leaf colors. We hypothesize that the cryptic coloration of A. bufo seedlings plays an important role in camouflage and that the numerous black spots on the surface of the petioles and rachises, may serve as a defensive mimicry against herbivores.
The development of Breinlia booliati is described in its natural host, Rattus sabanus and in an inbred strain of laboratory albino rat. The growth of the parasite is similar in both the rat hosts. The third moult occurs between six-eight days and the final moult between 24-28 days. Larvae were recovered initially from the skin and carcass. After five weeks, developing stages were seen only in the thoracic and abdominal cavities, the site of development of the adult worms. Worms became sexually mature by 11-12 weeks and there was considerable growth in length of the female worms after this stage.
Serological tests may yield false-negative results for specific antibodies detection before or at the early seroconversion phase. Tests that detect circulating antigens of Angiostrongylus cantonensis would therefore be of value in diagnosis to distinguish current or past infection. Here, a quick, easy to perform, portable and inexpensive diagnostic device for detection of 31-kDa A. cantonensis specific antigens had been developed. This sandwich dot-immunogold filtration assay (AcDIGFAAg), for detecting active angiostrongyliasis was produced using anti-A. cantonensis polyclonal antibody dotted on the nitrocellulose membrane as a capture agent and colloidal gold-labelled anti-31 kDa A. cantonensis antibody as a detection agent. A well-defined pink dot, indicating positivity, was seen readily by naked eye within 10-15 min. The AcDIGFAAg detected A. cantonensis-specific antigens in cerebrospinal fluid samples from 4 out of 10 serologically confirmed angiostrongyliasis cases and 2 out of 5 suspected cases with negative anti-A. cantonensis antibodies. Among the 19 patient sera with A. cantonensis infection, 2 showed positive reaction by AcDIGFAAg. No positive AcDIGFAAg reaction was observed in all the serum samples with other parasitic diseases, and the healthy controls. The present 'AcDIGFAAg' enables rapid qualitative detection of the specific 31-kDa antigens of A. cantonensis in clinical samples with potential for application even under resource-limited settings.
Freshwater snails, Stenomelania denisoniensis (Brot) from Tinaroo Dam, North Queensland, Australia were found to be infected with a heterophyid cercaria identified as Procerovum sp. The tail of the cercaria has finfolds which are bilateral anteriorly and dorso-ventral posteriorly, features which separate it from other genera in the Haplorchis-group. This group is differentiated from the cercariae of all the other heterophyid genera by the presence of the penetration glands that extend to the posterior end of the body lateral to the excretory bladder. This paper presents a full description of the cercaria, together with comparisons with other known species of Procerovum.
A total of 104 marine fish belonging to 12 species in 6 families were examined for anisakid larvae. All except one fish species were infected with one or more types of anisakid larvae. Three types of anisakid larvae were recovered, the most abundant being Anisakis type 1 (9 out of 11 fish species) followed by Contracaecum type B (6 out of 11) and Terranova type B (1 out of 11). Latianus malabaricus has the highest mean intensity of both Anisakis type 1 and Contracaecum type B. The public health hazard of anisakine nematodes is briefly discussed.
The ultrastructure of Sarcocystis sp. from the Malaysian house rat, Rattus rattus diardii, was studied with the electron microscope. The thin, uniformly-dense primary cyst wall had a row of vesicular invaginations which were also seen along the wall of the villi-like projections or cytophaneres. Within the villi were spherical bodies and hollow, curled structures. The ground substance beneath the primary cyst wall extended into the cyst as thin septa or trabeculae separating the tightly-packed zoites into compartments. Merozoites had a double-layered membrane, a conoid, 2 conoidal rings, 22 subpellicular microtubules, 6 rhoptries, 80-100 micronemes, scattered lipid droplets, and sac-like mitochrondrion, beside which was a Golgi apparatus. A micropore was occasionally seen at the anterior third of the zoite whereas the nucleus occupied the posterior third. Metrocytes were few in number and peripheral in location.
Preliminary studies have shown that Lymnaea rubiginosa, a common fresh-water snail in Peninsular Malaysia, which is easily colonized and reared in the laboratory, is a capable experimental intermediate host for Angiostrongylus malaysiensis. Overall 73% of the snails tested became infected following 6 hours exposure to infective rat faeces. Higher infection rates, up to 100%, and heavier worm loads, occurred among the larger sized snails. Snail attrition was low except when very heavy worm loads were acquired.