Administration to rats of tetramisole loaded into zeolite was more successful in killing adults of Nippostrongylus brasiliensis than the administration of tetramisole alone. The most successful treatment occurred in SPF (Specific Pathogen Free) rats dosed with tetramisole loaded into zeolite and no worms were present in this group at autopsy eight days post-infection. It is concluded that the slow release of drug from the zeolite matrix improved its efficacy, especially in removing worms from low-grade infections.

Two cases of intestinal obstruction due to Ascaris lumbricoides infection are reported from Ishaka Adventist Hospital, in south western Uganda. One was a male aged two and a half years and another was a female aged twenty. They were both treated surgically with good results. A review of the literature also revealed that intestinal obstruction due to A. lumbricoides is a common complication, though other surgical and nutritional complications also seem to be common, they are less reported.

During the latter half of 1930 and the beginning of the present year some miscellaneous experiments on Ascaris in pigs were carried out at the Institute of Agricultural Parasitology by Professor Leiper and myself. Although these experiments were of a preliminary nature it was thought that some of the observations made during their course might be of interest to other workers in this field and they are, therefore, placed on record.

Cooperia is the most prevalent helminth parasitizing calves in Brazil. Three species of this genus occur most often: C. punctata, C. pectinata and C. oncophora. Six calves from dairy farms in the south of the State of Minas Gerais aged six to 15 months were killed and necropsied each month over a period of two years. The Cooperia species were identified, counted, and the numbers related to the calves' age. The worm burdens due to the three species of Cooperia were statistically different. C. punctata was the most prevalent species and had a positive correlation with the age of the calves; C. pectinata appeared with lower intensity but was always present, and C. oncophora was not found in calves older than 11 months. These results show the existence of different degrees of resistance to Cooperia species among calves as the three species did not behave similarly. It seems to be an acquired resistance. C. punctata appears to be less immunogenic than C. pectinata and C. oncophora. As C. punctata and C. pectinata are more pathogenic than C. oncophora, it seems that this pathogenicity can be related to immunogenic aspects associated with the species.

In the course of an examination of unidentified Zoological material in the London School of Hygiene and Tropical Medicine, I recently came across a species of filarial worm from the portal vein of a North American Snake, Coluber melanoleucus, which I name Macdonaldius seetai n.g., n.sp.

Mel W is a second generation anionic organic arsenical which is filaricidal but has sporadic and unacceptable lethal side effects. Eight new cationic derivatives have now been synthesized in an attempt to avoid the side effects and have been examined for their effects upon adult Brugia pahangi in Meriones unguiculatus. They were all shown to be potent filaricides and the two best compounds, Mel Ga and Mel Cy, were at least 95% effective in killing adult B. pahangi at 5x3–13 mg/kg when injected subcutaneously.

Recent collection of lung fluke material from hydrophiid sea snakes permits a reevaluation of the suitability of criteria separating the monotypic genera Pulmovermis Coil and Kuntz, 1960 and Hydrophitrema Sandars, 1960. Consideration is also given of the new subfamily Pulmoverminae, erected by Sandars (1961) to include these genera within the digenetic family Hemiuridae. Typographical errors in the original description of H. gigantica Sandars, 1960 have been corrected, reducing the gross or external measurements of that species by ten times. Validity of characters such as flexure of the body, location of testes and ovary with respect to body length, length of seminal vesicle compared to body length, and anterior extension of the seminal vesicle with respect to acetabulum have been rejected. Retained are general body shape, relative position of acetabulum and development of peduncle, degree of coiling of seminal vesicle, and tandem or oblique arrangement of testes. Characters newly employed include body length-to-width ratio and presence of a cuticular fold in Hydrophitrema enclosing both suckers. Retention of the present genera based on these revised characterizations is recommended. Subfamily criteria (form, structure, and size of seminal vesicle, shape of vitellaria) are similar to those employed among the other nineteen subfamilies of this large and possibly heterogeneous group. In addition, these flukes are unique within the family on ecological and physiological grounds, in that they parasitize the lungs of sea snakes rather than the stomach of marine fishes, the usual site and host for members of this family.

In the spring of 1932, Mr. Otto Schierbeck, Chief Forester for the Province of Nova Scotia, forwarded several Black Ducks (Anas rubripes) which he had collected in a dead or dying condition on the shores of Cole Harbour, Nova Scotia, to the Animal Diseases Research Institute, Hull, Quebec. Mr. Schierbeck stated that the ducks had arrived there on their northward migratory flight six weeks earlier than usual, and after a period of hardship, had commenced to die in large numbers; and although the popular belief was that starvation was the cause of these deaths, he was not convinced that this was the case, owing to the apparently short period between the first signs of sickness and death.

Inorganic analysis of Ascaridia galli has shown the levels of sodium, potassium, copper, magnesium, calcium, zinc, iron, nitrogen, phosphorus, sulphur, chlorine and cobalt (expressed as percentage of dry weight) to be higher in females than in males.

The levels of nematode egg production in goats and the availability of infective larvae (L3) on pasture were investigated on a dairy unit in New South Wales, Australia. The output of eggs by adult goats was always above 300 epg. The profile of the graph of larval availability in herbage paralleled those for temperature and rainfall, suggesting that larval peaks occurred when the temperature and availability of moisture were optimal. The dominant genus was Trichostrongylus, followed by Haemonchus, then Ostertagia. A larger proportion of Haemonchus larvae in the cultures of faeces were collected during the summer months.

The known filaricides, suramin and diethylcarbamazine citrate, were tested against subperiodic Brugia malayi infection in the leaf-monkey, Presbytis cristata. As expected, intravenous suramin at 10 mg/kg daily × 5 days or 17 mg/kg weekly × 5 weeks, did not show any microfilaricidal activity, but substantially reduced the recovery of live adult worms to 50·6% and 13·6% of controls respectively. Oral diethylcarbamazine citrate at 6 mg/kg daily × 6 or 10 days reduced final microfilarial counts to 30% of initial counts four weeks post-treatment and adult worm recovery was reduced to 4·5% and 0% of controls respectively. Although the antifilarial activity of these drugs against the infection in this non-human primate model appears to be similar to that seen in man, these results have to be confirmed using larger groups of animals.

The nematode Trichostrongylus longispicularis was described by Gordon (1933) from a single male recovered from a sheep in New South Wales. Gordon considered that the male of this species could be readily distinguished from the males of other species of the genus recorded from ruminants by an asymmetrical dorsal ray of the bursa and by the length and form of the spicules. The dorsal ray is described as being bifid, one bifurcation being simple and the other possessing secondary branches, one situated internally and the other externally. The slender spicules were 184·6 microns long, and terminated in fine sickle-shaped structures.

Andrews (1934 and 1935) recorded the species from cattle in the United States. In his first description (Andrews, 1934) he noted that his specimens agreed very closely with the description published by Gordon (1933), but he referred to hook-like projections on the spicules. However, he failed to find these projections in the specimen discussed in his record of 1935. As he made no reference to the dorsal ray of the bursa, it is presumed that this agreed with the description and figure published by Gordon (1933). T. longispicularis was subsequently reported by Roberts (1938 and 1939) from cattle in Queensland, but no comments were made on its morphology.

A new member of the genus Trichostrongylus Looss, 1905, was collected by the writer from the gastric stomach (abomasum) and the duodenum of an old eland bull in 1981. The animal was shot at a spot amongst the Nega Nega Hills to the east of the Great North Motor Road in the Mazabuka Provincial District.

Eight males and twelve females were collected from the pyloric end of the abomasum which also harboured a large number of Haemonchus mitchelli LeRoux, 1929, and a few specimens of Ostertagia circumcincta (Stadelmann, 1894). Two more males and four females of the new species were encountered amongst a large number of Cooperia spp. including Cooperia neitzi, Mönnig, 1981.

Haemonchus contortus is a major parasite of small ruminants and its blood-feeding behaviour causes effects ranging from mild anaemia to death. Knowledge of the genetic variation within and among H. contortus populations can provide the foundation for understanding transmission patterns and aid in the control of haemonchosis. Adult male H. contortus were collected from three geographical regions in Egypt. The second internal transcribed spacer (ITS2) of nuclear ribosomal DNA was amplified using the polymerase chain reaction (PCR) and sequenced directly. The population genetic diversity and sequence variations were determined. Nucleotide sequence analyses revealed one genotype (ITS2) in all worms, without genetic differentiation. The similarity in population genetic diversity and genetic patterns observed among the three geographical regions could be attributed to possible movement between the sites. This is the first study of genetic variation in H. contortus in Egypt. The present results could have implications for the rapid characterization of H. contortus and other trichostrongyloid nematodes, and evaluation of the epidemiology of H. contortus in Egypt.

Bimiracidial infections of Lymnaea truncatula with three isolates of Fasciola gigantica, originating from China, Egypt and Madagascar, were carried out to determine the effect of geographic origin of the parasite on the larval productivity of redial generations. The prevalences of experimental infections in snails exposed to strains from Madagascar, China and Egypt were 20.8%, 60.0% and 80.0%, respectively. At day 49 post-exposure (p.e.), the total number of free rediae in snails infected with the Egyptian isolate was significantly higher than that recorded in the Madagascan group. On the other hand, at day 49 p.e., the majority of cercariae in the Chinese and Egyptian groups were produced by R2a rediae (70.6% and 66.6% of cercariae produced by all live rediae), while, in the Madagascan group, the cercariae were produced mainly by the first redial generation. Snails infected with the Egyptian isolate of miracidia developed more live rediae and, consequently, could produce a higher number of cercariae. As a result, L. truncatula snails were highly adapted to infections with the Egyptian and Chinese isolates of F. gigantica.

Through the generous co-operation of the British Antarctic Survey twelve Sheathbills were collected in April, 1967 at Signy Island, preserved in deep freeze, and made available to us for parasitological examination. Five of the Sheathbills were found to be infected with a new species of notocotylid trematode, namely Paramonostomum signiensis n.sp., which is described below and considered in relation to other species of Paramonostomum Lühe, 1909.

In the desert city of Beersheba, Israel, a survey was made of the infection rate of Toxocara canis in dogs. 3.0% of dogs destroyed at the municipal dog pound had intestinal T. canis. 7% of faecal samples gathered from day care centres throughout the city were shown to contain T. canis eggs. This low rate of infection could possibly be explained by the hot, arid climatic conditions which may render eggs non-infective or by the sandy soil in the area that may cover faeces containing T. canis ova and make the eggs unavailable to other dogs.

Three digeneans – Parahemiurus merus (Linton, 1910), Aphanurus stossichii (Monticelli, 1891) and Lecithochirium sp. – and one tetraphyllidean cestode larva were used as biological tags to discriminate the stock of Sardinella aurita (Valenciennes, 1847). In total, 579 fish were examined in five zones off the Tunisian coast, including Bizerte and Kelibia in the north, Mahdia in the east, Gabes and Zarzis in the south. Discriminant analyses used for the separation of S. aurita allowed for the identification of two discrete stocks. Sardinella aurita from Bizerte, Kelibia and Zarzis clumped together as a single stock. Parahemiurus merus and A. stossichii were the most important species in determining the location of sampled fish from these regions. Specimens from Mahdia and Gabes were grouped as one stock characterized by the presence of Lecithochirium sp. and larvae of the Tetraphyllidea. These results were corroborated by comparing the parameters of prevalence and mean abundance of parasites among zones. The separation of S. aurita between localities after pooling specimens from Bizerte, Kelibia and Zarzis and separately pooling those from Mahdia and Gabes also allowed the identification of two discrete stocks, one in offshore waters from Bizerte, Kelibia and Zarzis characterized by the digeneans P. merus and A. stossichii and one in inshore waters from Mahdia and Gabes characterized by Lechithochirium sp. and tetraphyllidean larvae.

The establishment, growth, survival and distribution ol Hymenolepis muris-sylvaticae m different laboratory animals (Wistar rats, golden hamsters, CFLP and NMRI mice) after oral infection and surgical transplantation were determined.

Worms that establish in CFLP and NMRI mice grow exponentially but are rejected at different times p.i. depending on the strain of mice and mode of infection. Only in golden hamsters will H. muris-sylvaticae develop to a mature worm; in rats there is no growth at all. Worms of all sizes are found in the posterior half of the small intestine in rats and both strains of mice; in hamsters the worms are recovered more anteriorly.

In March, 1928, Mr. S. F. Ashby of the Imperial Bureau of Mycology, sent the writer some portions of diseased banana roots for examination and determination of the nematodes occurring therein. The material had come from plants growing in the Palm House at the Royal Botanic Gardens, Kew, where bananas of several species had been growing for some years in the same soil. Information was later sent that the plants had been in failing health for the last two or three years and that this year the symptoms of disease had become acute. These symptoms were said to be quite similar to those described by Nowell (1919) in the case of diseased “bluggoe“ banana in Grenada with which Tylenchus musicola was found to be associated.