Dynamics of infestation of cattle and pasture by gastrointestinal nematodes in an Atlantic temperate environment.

The objective of the present study was to determine the dynamics of infestation of cattle and pasture by gastrointestinal nematodes in a mild humid environment in northwestern Spain. For this, infestation of pasture by free-living stages (L3), dynamics of faecal egg output, blood pepsinogen levels and worm burden in slaughtered animals were quantified. The results showed a high degree of annual variability, which was dependent on weather conditions. The seasons were clearly defined in the study area, with mild humid winters and relatively dry summers registered throughout the years of the study. Infestation of pasture by larvae varied from year to year, peaking during August in the first year, between August and December in the second year, and during October in the third year. The annual variation was mainly due to weather conditions, particularly the amount of rain in summer. The patterns of faecal egg output were similar in the first and third grazing seasons, with maximum levels observed in May/June; however, in the second year, the peak was reached in October. Blood pepsinogen levels increased from pasture turnout (March/April) until the end of the grazing season (November/December), reaching maximum values from August/September onwards. The nematode parasite species identified at necropsy were Ostertagia osteragi, O. lyrata, Cooperia oncophora, C. macmasteri, C. punctata and Trichuris ovis, with O. ostertagi and C. oncophora predominating. In faecal cultures, the following genera were also identified: Haemonchus, Trichostrongylus, Nematodirus, Bunostomum, Oesophagostomum and Strongyloides. There was a significant correlation (r=0.97, P<0.01) between worm burden (Ostertagia spp.) and pasture infestation (Ostertagia L3) 3 weeks prior to slaughter of the calves, and also between blood pepsinogen levels and pasture infestation by Ostertagia L3 (r=0.33, P<0.02). Correlations between worm burden and faecal egg output and between blood pepsinogen level and faecal egg output were not significant. The results obtained in the present study confirm that there is annual variability in the time-course of nematodosis in cattle, and demonstrate the importance of weather, particularly summer rainfall, in an Atlantic temperate environment.

On the Roman god Verminus.

An inscription from the II century BC, dedicated to the Roman god Verminus and considered to be due to the rising threat of human worm infections, is studied from linguistic and historical points of view. Having analyzed the historical sources we have reached the conclusion that the erection of the shrine was not related to the human helminthosis but to the epidemic infectuous disease which affected both animal and humans.

[Would not the Taenia be folium?]. / Le Taenia ne serait-il pas folium?

The name of Taenia solium is a problem for the latinists because solium cannot mean solitary. In some incunabula, appears the word folium. Because they studied latin and parasitology and because they know the possibility to confuse the s and the f in the gothic types, the authors are convinced, that the segment of the tapeworm, in the Breviarium attributed to Arnau de Vilanova, from which is originated the name of this worm was compared to a leaf (folium).

Population variability of Cernuella arigonis (Haas, 1929) (Mollusca: Helicidae) experimentally infected with Muellerius capillaris (Mueller, 1889) (Nematoda: Protostrongylidae).

Data on the level of infection and stage of larval development at the 12th and 40th days post-infection in the host-parasite system Cernuella arigonis (Haas, 1929) (Mollusca: Helicidae)/Muellerius capillaris (Mueller, 1889) (Nematoda: Protostronglylidae) were obtained. The results show the presence in an area of northern Spain of two varieties, geographic races or even sibling species of the host snail.

Broncho-pulmonary helminths of chamois (Rupicapra rupicapra parva) captured in North-West Spain: assessment from first stage larvae in faeces and lungs.

The bronchopulmonary helminths of 66 chamois (49 males and 17 females), captured in various parts of the Cantabrian mountain range (N. W. Spain) in the autumn of 1983, and in the summer and the autumn of 1984, were studied. The animals were adult and aged between 2 and 16 years. The lungs, trachea and faeces from the last section of the intestine were taken from each animal individually. The trachea and pulmonary larval nodules were dissected. First stage larvae (L-I) were obtained from finely cut up pulmonary tissue and from faeces by migration. The number of larvae I per gram varied between 0.08 and 2,662 (mean = 151.5 +/- 59.5 s. e.) in the faecal samples, and between 0.03 and 1,733 (mean = 65.2 +/- 32.4 s. e.) in the pulmonary ones. There was a low correlation between the two sets of data. When taking into account age and sex, no statistically significant differences were observed in relation to the number of larvae/gram found either in faeces or in pulmonary tissue, while there were statistically significant differences when considering the periods of sampling and reserve of origin, in relation to the larvae found in faeces and lungs, respectively. Infections by three nematodes (Neostrongylus, Muellerius and Protostrongylus) were more common than those produced by two or one, in the lungs as well as in the faeces. The most common genus was Neostrongylus, followed by Muellerius, and no Cystocaulus or Dictyocaulus larvae were found.

The history of veterinary parasitology in Spain.

A short history of the various contributions to the development of veterinary parasitology in Spain is given by considering five periods: (a) from the earliest times to the establishment of the first Veterinary Examination Board (Protoalbeiterato, A.D. 1500); (b) from 1500 to the creation of the Schools of Veterinary Medicine (1792-1793) and unification of the Veterinary profession (1850); (c) from 1850 to the appearance of parasitology as an autonomous discipline in the curricula; (d) from 1912 to the creation of Departments of Parasitology and Parasitic disease in the Faculties of Veterinary Medicine (1976); (e) from 1976 to the present day. In each period, the main contributions are considered and commented on, both from the parasitological and professional points of view. Finally, the role of veterinarians in modern Spanish parasitology is considered.

The experimental receptivity of Helicella (Helicella) itala and Cepaea nemoralis (Mollusca, Helicidae) to larvae of Muellerius sp. and Neostrongylus linearis (Nematoda, Protostrongylidae) from chamois (Rupicapra rupicapra).

Two batches of Helicella (H.) itala (adult specimen) and two of Cepaea nemoralis (adult and young specimens) were experimentally infected with larvae I (L-I) of Muellerius sp. and Neostrongylus linearis obtained from the lungs and faeces of Rupicapra rupicapra. In assess larval development, the number and percentage of the total number of larvae (L-I + L-II - L-III) per mollusc were studied, together with the number and percentage of L-III per snail and the days on which the different larval stages were reached. The development of Muellerius sp. and N. linearis was greater in larvae from faeces. For both species of molluscs, the values for the percentages of the total number of larvae and L-III were higher in N. linearis than in Muellerius sp., but there were no notable differences in the days on which the various larval stages were reached. Both nematodes achieved a greater degree of development in young specimens of C. nemoralis than in adults. Whether the larvae came from faeces or the lungs, H. (H.) itala was a better intermediate host than C. nemoralis for Muellerius sp. and N. linearis.

Standardized nomenclature of animal parasitic diseases (SNOAPAD).

An expert committee, appointed by the Executive Committee of the World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.), presents its proposal for uniform and proper terminology to denominate animal parasitic diseases or infections. In principle, the disease name is constructed solely by the suffix -osis, which is added to the stem of the name of the parasite taxon, formed from the nominative of the taxa. Standardized nomenclature of animal parasitic diseases (SNOAPAD) is meant as a guideline for general use, to improve the clarity of scientific communication. It should be especially useful in promoting effective usage of computerized data retrieval services.

Epizootiology of Eimeria ahsata coccidiosis in León (Spain).

The epizootiology of ovine coccidiosis caused by Eimeria ahsata was studied in four flocks in the province of León (Spain), between January 1978 and December 1979. The intensity of infection was found to be 25.5 +/- 1.7% and was similar in winter and spring. Eimeria ahsata was the most common species in 83.1% of the 1620 samples examined. It was also found in 86.2% of the animals examined. Only 0.3% of the positive samples contained oocysts of a single species, and samples containing four species were the most frequent (19%). Twenty-three percent of samples contained five species and 31.3% contained six species.

Quantity of Eimeria spp. oocyst elimination in sheep.

In the present paper, the results obtained are shown after a study by means of multivariant statistical analysis, of the quantity of Eimeria spp. oocyst elimination in sheep, bearing in mind the variations observed in the different areas, in the different age-groups, from month to month, and from year to year. Climatic factors, development of immunity, lambing seasons, and poor hygienic conditions seem to be the factors responsible for the statistically significant differences found when analysing the aforementioned main effects.

On first-stage larval resistance under controlled conditions of three species of nematodes of the family Protostrongylidae Leiper, 1926.

A study was made on the survival of the first larval-stage of three species of the Family Protostrongylidae (Cystocaulus ocreatus, Muellerius capillaris and Neostrongylus linearis). At every temperature (5, 12, 20, 26 and 36 degrees C) and humidity (100, 70 and 30%) combinations, the species which needed the least time to reach the pre-established (50, 75 and 95%) mortality rates was Neostrongylus linearis. In all cases Muellerius capillaris was the species needing the longest time to reach the same mortality percentages (rates). The direct relationship between the survival capacity of each species and their relative abundance in the grazing zone of the sheep used as a source of larvae studied is also discussed. The comparison of our results with those of other authors is made on the basis of an adaptive relationship between the species of parasites studied and their definitive hosts.

Teaching veterinary parasitology throughout the world.

In order to understand how the teaching of parasitology in veterinary schools and faculties in the world is carried out, a questionnaire was sent to all centres listed in the W.H.O. World Directory. A total of 91 replies were received. Additional information was obtained from the report of a symposium held in Hannover, Germany in 1978 and from the Education Committee of the American Association of Veterinary Parasitologists in 1981. The academic level, the place of parasitology in the veterinary curriculum, textbooks and practical instruction, evaluation techniques, teaching staff, institute organization and publications are discussed.

Migration and growth of Neostrongylus linearis (Marotel, 1913) Gebauer, 1932 in sheep.

In order to establish the mammalian parasitic cycle of the nematode Neostrongylus linearis 18 lambs were infected with 5000 third-stage larvae obtained from the snail Cernuella (Xeromagna) cespitum arigonis. In the subsequent days, larvae were found in the walls of the caecum and colon, in the liver and the lungs, suggesting that the bloodstream is the main migratory route. The presence of low numbers of migrating larvae in the mesenteric lymph nodes indicates that this route is probably secondary. The first still sexually undifferentiated, fourth-stage larvae were found in the lungs on the 8th day post-infection (p.i.) and the first sexually differentiated fifth-stage larvae, on the 10th day. Also described are the macroscopic changes of the parasitized organs.

[Dose as the determining factor for the size of the parasite population in the Muellerius capillaris/Cernuella cespitum arigonis system (Nematoda, Protostrongylidae/Mollusca, Stylommatophora]. / Die Dosis als Regelfaktor für die Grösse der Parasitenpopulation im System Muellerius capillaris/Cernuella cespitum arigonis (Nematoda, Protostrongylidae/Mollusca, Stylommatophora).

Ten lots, each one made up of 40 specimens of the snail Cernuella (Xeromagna) cespitum arigonis, were infected with L1 of the nematode Muellerius capillaris, at dosages ranging from 50 up to 1,000 L1/mollusc, in order to determine the influence of the infecting dose on the invasion and further development of the parasite population. Mathematical calculations are based on a basic model of a growing population. During the invasion phase a densith dependence on the number of available larvae was demonstrated, the process being adjusted to a binomial distribution and, secondly, to a Poisson type. The step from L1 to L2 was also density-dependent, and also the development from L2 to L3.