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The 1981 annotated checklist of Tenquist and Charleston is completely revised Forty five new records have been added, and recent taxonomic changes are included for both hosts and parasites

To investigate the effect of feeding forage legumes containing condensed tannins (CT) on internal parasitism, red deer calves were fed either lucerne (Medicago sativa; 0.1 per cent CT), birdsfoot trefoil (Lotus corniculatus; 1.9 per cent CT) or sulla (Hedysarum coronarium; 3.5 per cent CT) and trickle-infected with deer-origin gastrointestinal nematode and lungworm (Dictyocaulus sp.) larvae for 5 weeks, then slaughtered at 7 weeks. There was a significant negative linear relationship between dietary CT concentration and abomasal nematode burdens. No significant differences in faecal egg counts, lungworm burdens or voluntary feed intake were found. Deer fed sulla had higher liveweight gain, carcass weight and carcass dressing-out percentage, higher serum total protein and albumin concentration and lower serum gastrin concentration and faecal lungworm larval count, compared with lucerne-fed deer. Inclusion of sulla in diets for young red deer may reduce the impact of internal parasites and/or reduce the dependence on anthelmintic treatment.

A rotational grazing experiment using weaner deer was conducted at Palmerston North, New Zealand, during the autumn, winter and spring, to compare the voluntary feed intake (VFI), liveweight gain (LWG) and carcass production of deer grazing chicory with those grazing perennial ryegrass/white clover pasture. Deer were either treated with anthelmintic at 3-weekly intervals (T) or anthelmintic was withheld until trigger-treatment (TT) criteria were attained. Pure red and 0·75 red: 0·25 elk hybrid stags and hinds were given forage allowances of 5 kg DM/deer/day in autumn and early-mid winter, 6 kg DM/deer/day in late winter and 7 kg DM/deer/day in spring. Deer grazed chicory or pasture in autumn and spring, with all deer combined on pasture during winter when chicory was dormant. Organic matter digestibility of diet selected was greater for chicory than for pasture in both autumn and spring. Anthelmintic-treated deer grazing pasture in autumn had significantly higher VFI and LWG, contributing to higher carcass weights, than TT deer. Anthelmintic treatment had no effect on these measures for deer grazing chicory in autumn. Clinical signs of lungworm infection were evident in pasture TT deer during autumn and winter, and in chicory TT deer grazing pasture during winter. Faecal egg counts (FEC) were significantly greater for pasture TT deer during autumn and early winter than all other groups. Faecal lungworm larval counts (FLC) were significantly greater for chicory TT deer following transfer to pasture, than for all other groups in early winter, although both FEC and FLC were low. Faecal larval counts were poorly related to clinical signs of lungworm infection during autumn, but were a better guide in winter. Plasma pepsinogen concentrations appeared unrelated to gastrointestinal parasite infection. Trigger-treated deer grazing pasture required five anthelmintic treatments during autumn and winter. The chicory TT group required no anthelmintic treatment when grazing chicory during autumn, but required two treatments after transfer from chicory to pasture during winter. There was no effect of anthelmintic regime on VFI and LWG in spring, and LWG was greater for deer grazing chicory than those grazing pasture. Hybrid deer had greater spring LWG and carcass weights than red deer when grazing chicory, but similar LWG and carcass weights when grazing pasture. It was concluded that grazing chicory offers the potential for reducing anthelmintic use in farmed weaner deer, particularly during autumn.

The methodology and results of a parasite survey of 209 possums from Wanganui, western North Island, in the spring of 1994 are described. No somatic protozoan parasites were detected, but 23% of possums had coccidia, Eimeria sp. Oocysts in their faeces. Prevalences of intestinal nematodes were: Parastrongyloides trichosuri (55%), Trichos‐trongylus spp. (59%), and Paraustrostrongylus trichosuri (2.4%). Only one animal was found infected with the cestode Bertiella trichosuri. It was demonstrated that prevalence of Parastrongyloides trichosuri was affected by age and habitat and Trichostrongylus spp. by habitat. Four species of external parasites were found: the mites Tricho‐surolaelaps crassipes (49%), Petrogalochirus dycei (65%), Atellana papilio (81%), and Murichirus anabiotus (32%). The parasite fauna of possums in New Zealand appears to be less diverse than that in their native Australia.

SUMMARY The role of antibody in the resistance of sheep to infection with Taenia hydatigena metacestodes was examined using passive transfer of immunoglobulin. The immunoglobulin either was experimentally transferred in serum, or was transferred from immune ewes to their new-born lambs in colostrum. Pooled serum from donor lambs which had received one, light, oral infection did not protect recipients although the donors themselves were immune. However, transfer of pooled serum from donors which had either received three oral infections, or three immunizations with solubilized T. hydatigena oncospheres in a water-in-oil adjuvant, resulted in 70–80% fewer cysts in the recipients. Colostrum from ewes infected with three high or low doses of T. hydatigena eggs was transferred to their lambs. A short acting protection (one to three weeks) was observed in the lambs. Comparisons by ELISA and Western blot, of the anti-T. hydatigena oncosphere antibody content of the donor sera, the sera of the recipients collected 24 h and seven days after transfer, the sera of the lambs and ewes, and the colostrum of the ewes, indicated that resistance to the challenge infection depends upon a critical level of antibody.

Of the protozoans infecting domesticated animals and humans in New Zealand, it is undoubtedly the apicomplexans that are most important. These include Toxoplasma, Sarcocystis, Eimeria, Cryptosporidium, and Neospora species. All have the potential to cause both clinical disease in animals and subclinical losses of production and, in some industries, they necessitate the use of costly preventive measures. Some are also potentially important to human health and others to the acceptability of meat products. There have been very few attempts to estimate the economic significance of infections with these parasites in this country and it is difficult to do so. In this paper, I review the biology and prevalence of these infections in New Zealand, attempt to estimate the significance of at least some of them, and discuss the problems associated with doing so.

Differences in helminth faunal composition, distribution and abundance were studied in three habitats on an island on which the Polynesian rat, Rattus exulans (Peale), is the only rodent present. The effects of season and of host age and sex were also included in the analysis. Habitat had a statistically significant effect on the prevalence and/or abundance of all seven parasites included in this study. Season influenced four species (Brachylaima apoplania, Capillaria sp., Heterakis spumosa and Mastophorus muris) but had little or no detectable effect on the remaining three (Capillaria hepatica, Hymenolepis diminuta and Syphacia muris). Of the two intrinsic variables, age but not sex was found to have an effect. A comparison of the effects of each variable on parasite prevalence confirmed that habitat was the most important of the four variables. In a prior study on the influence of habitat on host population dynamics on this island, between-habitat differences were shown to include adult longevity, total population density and the seasonal availability and abundance of various food types. These factors, together with physical differences in the microhabitat and the parasite's life cycle, help to provide explanations for the observed results.

The potential for spread by feral cats of parasites infecting sheep and cattle was investigated on 5 km2 of New Zealand farmland. Faeces were collected to study diet and the prevalence of Sarcocystis and other parasites. The diet consisted primarily of rodents (50% by weight) with scavenged sheep (7%) relatively unimportant. Sarcocystis sporocysts were found in 4.8% of the faeces samples; given the predominance of rodents in the diet, it is more likely that these derived from species infecting rodents rather than farm animals. Toxoplasma gondii oocysts were not found. Eggs of the nematodes Toxocara cati and Capillaria spp. occurred in 67 and 52% of the samples, respectively. The home range and movements of feral cats were estimated using radiotelemetry. Female cats using barns and pasture had larger home ranges (1.88-2.79 km2) than those living in willows (0.37-1.09 km2). Adult males and a dispersing subadult male had larger home ranges (2.76-3.00 km2) than females. The density of resident feral ...

A study of 28 infections in 22 individually housed cats fed excised cysts of Sarcocystis gigantea from naturally infected sheep, revealed a consistent pattern of sporocyst shedding. In all cats, sporocyst excretion commenced 10 or 11 days postinfection (PI). Peak production occurred between 13 and 22 days PI, in most instances on Days 17and 18. Peaknumbers (rounded) rangedfrom 550 to 260 000 (mean = 53 000) sporocysts per gram of faeces or from 38 000 to 6.6 million (mean = 1.7 million) sporocysts per day. The number of days sporocysts were shed ranged from 26 to at least 60 days PI but in 26 of the 28 infections examined, > 80% of the total sporocyst yield was produced within 30 days of infection. The total numbers of sporocysts produced by individual cats over the patent period ranged from 164 000 to 56.6 million (mean = 12.7 million). These numbers tended to increase with increasing infective dose and tobe greater in those cats receiving multiple rather than equivalent single doses. Neither th...

A general review of the epidemiology, significance and control of nematode parasitism of sheep, goats, cattle and deer in New Zealand, the emergence of anthelmintic resistance and its effects, and the search for parasite control strategies that reduce reliance on anthelmintic use, is provided. The research that has formed the basis for present levels of understanding of this complex and important topic is summarised and sources of further information are indicated. Aspects of nematode infections of horses, pigs, dogs and cats, and the history of the liver fluke, Fasciola hepatica, in New Zealand are also reviewed briefly.

Twelve male and 12 female adult possums, Trichosurus vulpecula (Kerr), held in captivity, were fed a commercial pelleted diet for 8 weeks. Their ages ranged from 2 to 9 years and their body weights from 2.0 to 3.7 kg. Food, faeces, and urine were chemically analysed. On average the possums ate approximately 80 g dry weight of food daily (40 g/kg body weight-0.75), and they maintained body weicht. Their mean maintenance requirement of nitrogen was just over 2 g daily (1.0 g.d-su1.kg BW0.75). The possums were killed at the end of the experiment, and weights of various oreans, body composition analyses, blood chemical data, gut microbiology examinations, and skeletal radiographs revealed few significant differences between males and females. The anatomical and physiological data obtained can be taken as representative of healthy possums on an adequate, balanced artificial diet.

At a constant temperature and humidity there was a linear relationship between the log of survival time and the log of shell length in Lymnaea tomentosa and L. columella. Reasons are suggested for this relationship. There was no significant species difference in ability to resist desiccation, provided specimens of either species were of similar shell-length.

One hundred and forty-seven species of parasites (59 Acari, 11 Amblycera, 30 Diptera, 1 Hemiptera, 1 Perttastomida, 28 Phthiraptera, 17 Siphonaptera), together with their synonyms and common names, are listed from 30 species of wild, feral or domestic animals and man from New Zealand and offshore islands. Where known, geographical distribution and range are included; indexes for cross referencing are provided.

Data obtained from faecal samples from 508 domestic cats and 481 dogs, previously found to have a high frequency of Sarcocystis spp. infections, were further examined to provide information on levels of sporocyst shedding and to ascertain the influence of host, environmental and seasonal factors on the prevalence of naturally acquired infections. Statistical analysis of prevalence data revealed that, of the factors examined, only host age in cats exerted any apparent influence. Infections were significantly more common in cats up to, rather than over, 6 months of age. Although they tended to be greater in dogs than cats, faecal sporocyst counts in both hosts were generally low, with the majority of infected samples containing 200 sporocysts per gram or less. In infected dogs the highest count recorded was 144,600/g with a mean of 2270/g, and in infected cats it was 11,100/g with a mean of 597/g.

The effect of Oesophagostomum dentatum on the performance of growing pigs over the live-weight range 20 to 80 kg was investigated. Fourteen individually-penned pigs in Experiment 1 and 16 group-penned but individually fed pigs in Experiment 2 were orally dosed once with 80 000 or 20 000 larvae respectively at about 18 kg live weight. Worm-free but otherwise similar pigs served as controls. Three energy and nitrogen balance studies were undertaken in two open-circuit calorimeters on four infected gilts and their paired worm-free counterparts on two levels of feeding at 7, 21 and 49 days after infection. Worm burdens averaging 4 255 and 4 722 in Experiments 1 and 2 respectively were recorded post mortem but performance and carcass measurements were not affected, neither were there any clinical symptoms. No significant differences between infected and worm-free pigs were recorded for either apparent digestibility of nitrogen and gross energy or for nitrogen retention. Possible reasons for the lack of measurable effects on pig performance are discussed.

Examination of stomach contents from 191 Rattus r. rattus, trapped over 12 months in an area of bush in the Manawatu district, revealed that 123 (64.4%) of the rats were infected with Physaloptera getula (Physalopteridae) and 39 (20.4%) with Mastophorus muris (Spiruridae). The high prevalence of P. getula did not vary significantly during the year, but there were marked seasonal variations in the numbers of worms per rat, the highest mean counts occurring in autumn and the lowest in late winter and spring. The prevalence of M. muris varied significantly through the year, and was highest in autumn. Mean worm counts per rat appeared to be biphasic, with peaks in spring and autumn; however, since only small numbers of animals were infected, this may not represent what actually occurs. The majority of infections with both nematode species comprised less than 10 worms. Possible reasons for the seasonal variation in prevalence and intensity of infections are discussed. Circumstantial evidence suggests ...

Macroscopically visible spherical cysts measuring up to 260/μm in diameter and showing characteristics typical of those of the genus Besnoitia were observed in rats dosed with isosporan oocysts recovered from the faeces of a feral cat. Kittens fed these rats shed similar oocysts measuring 16.9 ± 0.1 × 14.6 ± 0.1 μm in their faeces 11–12days later. The feeding of sporulated oocysts of this coccidian to mice, rats, rabbits and guinea pigs resulted in the formation of Besnoitia cystsin all hosts except the last. Besnoitia is the fourth sporozoan genus, together with Isospora, Toxoplasma, and Sarcocystis to be recovered from New Zealand cats.

Sarcocysts morphologically similar to Sarcocystis muris were observed in the skeletal muscles of mice dosed with free isosporan sporocysts recovered from the faeces of naturally infected cats. Kittens fed these mice shed similar sporocysts measuring 8.7 ±0.1 x 10.8 ±0.1 μm in their faeces five to six days later. Feeding these sporocysts to mice and rats resulted in the formation of identical sarcocysts in mice, but not rats. Attempts to induce similar infections in mice using naturally acquired isolates of I. felis were unsuccessful.

Cellular changes in the spleens of mice infected with Sarcocystis muris have been studied. Immunofluorescent staining for B and T cells and alpha-naphthyl acetate esterase (ANAE) staining for macrophages combined with histological studies revealed marked changes in the populations and distributions of all three cell types. Infection was accompanied by a marked splenomegaly, attributable mainly to widespread hyperplasia of the white pulp. Following infection there was an increase in the relative proportions of B cells (i.e. surface immunoglobulin+) and ANAE+ cells and a decrease in the proportion of T cells (i.e. Thy 1.2+). There was also a progressive accumulation of immunoglobulin-containing cells in the periarteriolar lymphocytic sheaths. Splenomegaly was most pronounced 20 days after infection. At this time there were 9.3 times as many B cells, 3.7 times as many T cells and 16.6 times as many ANAE+ cells as in uninfected mice.

The occurrence in New Zealand of Lymnaea auricularia (L.) is recorded for the first time, and its status world-wide is briefly discussed, with particular reference to its role in economic parasitology. The lymnaeid fauna of New Zealand is briefly reviewed.

Studies on the activation and excystation of I. felis and I. rivolta sporozoites revealed that, although some differences were apparent between the two, both were capable of activation under a wide range of conditions. Activation of both species took place in trypsin and bile between 21 and 43 C (the range tested) occurring rapidly at 39 C. Although the presence of bile appeared to be essential for this process that of trypsin did not. Neither the concentration of bile (above 5%), the type of bile, nor the hydrogen ion concentration had a marked effect on the level of activation. Pretreatment of oocysts in aqueous cysteine hydrochloride under CO2 or with sodium hypochlorite before exposure to trypsin and bile was not an essential prerequisite for the activation of I. felis and I. rivolta. However, higher levels of activation were attained when pretreatment was used. But for I. rivolta, the level of activation appeared to be less dependent on pretreatment for oocysts stored in sulfuric acid than for those stored in potassium dichromate. The process of activation and excystation of both species was essentially similar to that de- scribed for other species of disporocystic coccidia with heteroxenous life cycles. Sporozoites escaped following the collapse of the sporocyst wall and completed excystation through indentations and fractures at one or both ends of the oocyst.