Modelos de control quimioterapéutico contra Fasciola hepatica en ganado bovino en pastoreo en clima cálido húmedo

2 páginas.-- Trabajo presentado al XIII Congreso Latinoamericano de Parasitología ( La Habana, Cuba, 11 al 23 de Noviembre, 1997).La fasciolosis en bovinos en el estado de Veracruz, México, tiene una alta prevalencia, por lo que se considera una necesidad generar información sobre modelos de control. Con el objetivo de evaluar 3 modelos de tratamientos fasciolicidas aplicados de manera estratégica en base a las condiciones climatológicas locales, se emplearon 3 grupos de 23 vacunos cada uno, hembras cruces de cebú con suizo pardo, homogéneos en las cantidades de huevos de 5 g de heces. Se utilizó el triclabendazol a dosis de 12 mg/kg. El grupo 1 fue tratado en enero, el 2 en enero y junio, y el 3 en enero, junio y octubre. Cada 45 días se les practicaron exámenes coprológicos cuantitativos (hpg) por la técnica de sedimentación durante un año. Los bovinos se encontraban localizados en una finca situada en el municipio de Nautla, Estado de Veracruz. Se encontró en el grupo 1 la prevalencia al inicio de 100%, en los siguientes 5 muestreos fue de 21.7 a 91.3 % y en el resto de 100%, mientras que el x de hpg al inicio fue de 13.23.14 se redujo en 5 muestreos de 0.560.26 a 12.12.02 mientras que en 4 se incrementó de 14.63.87 a 21.1 3.06 con diferencia (P0.01) entre el primer muestreo y los siguientes. En el grupo 2 la prevalencia al inicio fue de 100%, posteriormente se redujo en 8 muestreos de 8.6% a 95.6%, mientras que el último muestreo fue de 100%, el x de hpg al inicio fue de 15.043.62 se redujo en 8 muestreos de 0.170.13 a 14.102.13 mientras que el penúltimo muestreo fue de 15.733.07 con diferencia entre el primer muestreo hasta el 8, pero sin diferencia con el 9 y el 10 (P0.01). En el grupo 3 la prevalencia al inicio fue de 100% en los siguientes muestreos se redujo de 15.07% a 94.4%, mientras el x de hpg al inicio fue de 13.132.24 disminuyó en los subsecuentes muestreos 0.270.13 a 11.554.56 se encontró que hubo diferencia entre el primer muestreo con todos los subsecuentes (P0.01). Al comparar entre grupos mediante la prueba de Kruskall-Wallis se encontró que hay diferencia (P0.01) del muestreo 8 al 10.Peer reviewe

Transmission of Calicophoron daubneyi and Fasciola hepatica in Galicia (Spain): Temporal follow-up in the intermediate and definitive hosts

Background Paramphistomosis caused by Calicophoron daubneyi and fasciolosis caused by Fasciola hepatica are common parasitic diseases of livestock animals. Transmission of the diseases depends on the presence of intermediate hosts, i.e. freshwater gastropods such as lymnaeids. We carried out a 2-year-long study of the dynamics of the snail population acting as the intermediate host for these parasites, considering the population structure in terms of size/age and infection status. In addition, we determined the kinetics of trematode egg excretion in grazing cows. Generalized Additive Models (GAMs) were used to analyze the associations between different response variables and snail size, sampling month and weather-related variables. Results Of the molluscan species examined, Galba truncatula, Radix peregra, Anisus (Anisus) leucostoma and Pisidium casertanum (n = 2802), only G. truncatula was infected with C. daubneyi or F. hepatica, at prevalence rates of 8.2% and 4.4% respectively. The probability of infection with C. daubneyi or F. hepatica was linearly related to snail size, although in different ways (negative for C. daubneyi and positive for F. hepatica). The total snail population increased in winter, when specimens of all size classes were found. Infected snails were more abundant during spring-autumn. Mature cercariae of both parasites were found in most seasons. In the statistical models, the sampling month accounted for a high percentage (71.9–78.2%) of the observed variability in snail abundance. The inclusion of climatic variables in the models moderately increased the percentage of deviance explained (77.7–91.9%). Excretion of C. daubneyi eggs in cow faeces was always higher than that of F. hepatica eggs. Conclusions Particular care should be taken to prevent pastures and the surrounding environment being contaminated with parasite eggs during winter-spring, when the number of snails susceptible to miracidial infections is maximal. This is therefore the optimal time for treating grazing animals. Nevertheless, control of trematodosis based only on chemotherapy is difficult in an area such as the study area, where environmental factors favour the regular appearance of snail populations harbouring mature cercariaeThe present study was financially supported by the Ministerio de Economía y Competitividad (AGL2011-30563-C03-03). The funders did not have any role in the study design, data collection and analyses, decision to publish or preparation of the manuscriptS

Calicophoron daubneyi (Paramphistomidae) in slaughtered cattle in Castilla y León (Spain)

The prevalence and aetiology of natural paramphistomosis was investigated in cattle slaughtered in the Castilla y León region (Spain) over a 3 year-period. The overall prevalence of positive animals was 6.20%. The parasite burden per animal ranged from 8 to 8005 (median = 144) and the ruminal atrium had the highest parasite burden whereas the ruminal dorsal sac the lowest. The prevalence and parasite burden increased with age while these parameters were lower in cattle under intensive management. Calicophoron daubneyi was the only Paramphistomidae species identified using morphoanatomical, histological and molecular methods in the studied animals.This work was supported by grant LE023A10-2 fromJunta de Castilla y León (JCyL). A.M. Martínez-Ibeas was supported by the JCyL andthe European Social Funds (ESF) and J. Benavides by theJAE-Doc programme (CSIC-ESF).Peer Reviewe

Al profesor Dr. Miguel Cordero del Campillo, mi maestro

2 páginas.El Curriculum vitae de Don Miguel Cordero, quien fue Catedrático de Parasitología y Enfermedades Parasitarias de la Facultad de Veterinaria de León, y hoy Profesor Emérito, es tan extenso que necesitaríamos muchas páginas para poder resumirlo. Por eso, en esta corta nota, comentaré únicamente algunas de mis vivencias desde que lo conocí. Mi primer recuerdo consciente del Profesor Miguel Cordero del Campillo se remonta al día en el que se iniciaron las clases de la Carrera de Biológicas en León. Digo que fue mi primer recuerdo consciente, pues creo que en uno de los exámenes de la “Prueba de Madurez,” que realicé al finalizar el curso “Preuniversitario”, fue también el Profesor Cordero quien nos impartió la conferencia reglamentaria, aunque no podría asegurarlo...Peer reviewe

Importancia de los moluscos en la transmisión de enfermedades parasitarias al ganado

2 páginas.-- Trabajo presentado al XIII Congreso Latinoamericano de Parasitología (La Habana, Cuba, 11 al 23 de noviembre de 1997)El phylum Mollusca es el segundo en el reino animal en cuanto al número de especies, las cuales difieren considerablemente en organización y hábitat. Los moluscos implicados en la epidemiología de las principales parasitosis de ciclo indirecto que afectan al ganado, y a veces al hombre, pertenecen primordialmente a la subclase Pulmonata, clase Gastropoda. Dichos moluscos son imprescindibles en la transmisión de las parasitosis producidas por Digenea, puesto que practicamente todas las especies responsables de las mismas los utilizan en su ciclo biológico como primeros hospedadores intermediarios (H.I). En el molusco el parásito se multiplica enormemente por reproducción asexuada, lo que hace que aumenten las posibilidades de éxito en la transmisión parasitaria, pues de un solo miracidio se producirán numerosas cercarias, que desarrolladas en esporocistos o redias, abandonarán el molusco para: penetrar en el hospedador definitivo, enquistarse en el medio externo o buscar un segundo H.I., que a veces es también un molusco. Fasciolidae, Paramphistomidae y Schistosomatidae son algunas de las familias de Digenea importantes para el ganado, cuyas especies utilizan en el ciclo biológico moluscos pulmonados de agua dulce (Basommatophora), pertenecientes a las familias Lymnaeidae y Planorbidae. Las especies de Dicrocoeliidae evolucionan en moluscos pulmonados terrestres (Stylommatophora) de las familias: Achatinidae, Bradybaenidae, Cochlicopidae, Chondrinidae, Enidae y Helicidae. Las larvas de parásitos Nematoda, que utilizan moluscos como H.I., no se reproducen en su interior aunque si evolucionan de larva-1 a larva-3, estado infectante para el ganado. Las especies de Protostrongylidae, responsables de la bronconeumonías verminosas ovinas, utilizan moluscos Stylommatophora (Arionidae, Enidae, Helicidae, Limacidae, Parmacellidae y Zonitidae) y algunos Basommatophora (Lymnaeidae). Los Cestoda de la familia Davaineidae evolucionan de oncosfera hasta cisticercoide en moluscos Stylommatophora (Arionidae, Helicidae, Limacidae, Polygyridae, Zonidae).Peer reviewe

Field and experimental studies on Dicrocoelium dendriticum and dicrocoeliasis in northern Spain

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=713380The transmission, control and the relationship between Dicrocoelium dendriticum and its definitive (sheep and cattle) and intermediate (molluscs and ants) hosts under natural and experimental conditions are described. Eleven species of molluscs and four of ants were found infected with larval D. dendriticum in León province, north-west Spain. Infected ants were observed between April and November and in tetania at 7.5-26.9 degrees C. The highest shedding of eggs by sheep and cattle was detected in winter. Two treatments applied in November and January were the most effective. In experimentally infected molluscs, the parasite was not visible under the stereomicroscope, at least until 50 days post-infection (p.i.). The prepatent period in experimentally infected lambs was 49-79 days p.i. The number of eggs per gram increased with the days p.i. and the parasite burden. The aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase, leukocyte and neutrophil values of infected lambs increased, but those of lymphocytes decreased. Using the enzyme-linked immunosorbert assay technique, the IgG antibody response to excretory-secretory and somatic antigens of D. dendriticum was positive from day 30 p.i., although the maximum antibody levels were observed on day 60 p.i. The number of worms per lamb ranged between 30 and 2063. Cholangitis and cholangiectasia of the septal bile and hepatic ducts were observed. The best enzymatic systems for adult and larval D. dendriticum characterization were lactate dehydrogenase, glucose phosphate isomerase and phosphoglucomutase. Genetic variability of adult D. dendriticum was high using the random amplified polymorphic DNA technique.Peer reviewe

Trematodos

Capítulo 8.-- En Parasitología General.- Cordero del Campillo, M., Rojo Vázquez, F. A., Martínez Fernández, A.R., Sánchez Acedo, M. C., Hernández Rodriguez, S., Navarrete López-Cozar, I., Díez Baños, P., Quiroz Romero, H. & Carvalho Varela, M. (Eds.)Peer reviewe

In memoriam. Gloria Perera de Puga 1949-2000

4 páginas.Peer reviewe

Dicrocoelium dendriticum and dicrocoeliosis: a review of our research

2 pages.-- Comunicación presentada al IX European Multicolloquium of Parasitology (Valencia, España, 18-23 July, 2004)Dicrocoeliosis, caused by D. dendriticum, is an important parasitic disease from an economic and health viewpoint. This trematode, whose adults live in the liver and bile ducts of numerous mammal species, mainly ruminant, which act as defmitive hosts in several countries in Europe, Asia, America and North Africa, needs land molluscs and ants as first and second intermediate hosts, respectively, to complete it life cycle. D. dendriticum occasionally affects humans. The application of efficacious prophylactic and control measures against dicrocoeliosis -which have not been satisfactory so far-, requires precise early diagnosis, a previous epidemiological study and experimental research to help interpret field observations and extend knowledge of the parasite/host relationships. We therefore decided to carry out studies on: epidemiology; strategic treatments; experimental infection in molluscs, hamsters and lambs; parasite isoenzymatic characterisation and genetic variability; and antigenic molecules as targets for specific diagnosis and protection. Our research on D. dendriticum started 30 years ago, mainly focusing on the specific determination, distribution and natural infection by trematodes of 23 species of Helicidae (Mollusca) collected over 12 years in more than 350 villages throughout the province of León (NW Spain). This parasite was detected in 11 mollusc species collected in 95 of these villages. Likewise, the monthly kinetic of D. dendriticum egg elimination in faeces of sheep and cattle chosen at random in 5 localities in the upper and middle Porma river basin was followed for one year. We found D. dendriticum eggs in 63.6% and 37.6% of the 995 and 1251 sheep and cattle samples examined, respectively. The highest egg-elimination period in both was the end of autumn-winter. Moreover, simultaneous and integrated studies conceming the transmission of D. dendriticum were carried out on 81 labelled sheep and lambs, molluscs and ants, over two consecutive years in one of the mountain localities with the highest infection prevalence detected (73.7%) and epg (x 398.8) in randomly sampled sheep. Two Helicella of the 29 Gastropoda species identified contained D. dendriticum. Daughter sporocysts with well-developed cercariae predominated in spring and autumn. Four Formica of the 21 ant species studied harboured metacercariae in the abdomen. Infected ants were detected from April to November and in tetania from May to October (from 06.00-14.10 and 18-21.5 hours, at 7.5-26.9 °C). The highest values of egg elimination in all the animals were detected in January-February.According to our results, shedding of D. dendriticum eggs with the faeces of the ruminants occurs uninterruptedly throughout the year, but the highest values are recorded at the end of autumn-winter. At these times survival of D. dendriticum eggs is very high (low temperatures do not affect egg survival), so pastare contamination by viable eggs is very great in spring, when the molluscs are very abundant and active. Those infected at the beginning of this period could shed slimeballs with cercariae at the end of summer and during autumn, whilst those infected later can shed slimeballs the following year, beginning in spring, if they survive the harsh winter. Approximately 45 days later the cercariae ingested by ants will have become infected metacercariae for the definitive hosts. This will allow the parasite cycle to be completed when the ants are ingested by ruminants on grazing, during the active period of the ants (March-November). Nevertheless, some infected ants survíve in their nest during the winter, and they are responsible for definitive host infection at the beginning of spring. As the ant activity increases, so does metacercariae ingestion by the definitive hosts and their D. dendriticum worms increases. Thus, egg elimination also increases during this period, reaching the highest values in January-February (Manga-González et al., 2001). Two treatments applied in November and January were the most effective to reduce egg shedding by natural infected sheep. The ovine experimental dicrocoeliosis studies were carried out on 32 lambs: 12 infected with 1000 D. dendriticum metacercariae, 12 with 3000 and 8 controls. Half the lambs in each group were slaughtered on day 60 and 180 p.i., respectively. The percentage of metacercariae established as adult worms in the total of infected lambs was 17%. The worms recovered on necropsy of each animal was 110-2063 worms (dose 3000) and 30-437 worms (dose 1000). Egg elimination was first detected between days 49 and 79 pi. The highest epg values were observed 180 days p.i. (Campo et al., 2000). The increased AST and ALT enzyme values were significant 60 days p.i., when the IgG antibody response against excretory-secretory and somatic antigens was highest and the greatest decrease in the weight of the lambs took place. Severity of the lesions observed in experimental dicrocoeliosis, affecting mainly the biliary system but also hepatocytes, was closely associated with the parasitic burden. The best enzymatic systems for the characterisation of the D. dendriticum adults and larval stages were LDH, GPI and PGM.Work supported by: “Junta de Castilla y León” (Project No.070l/89), British Council-Spanish Ministry of Education and Science (1990 HB 171 A; 1991 HB 199 A) and Spanish CICYT (Projects: AG92-0588, AGF96-04l6, AGL2001-1290).Peer reviewe

Some land mollusc species involved in the life cycle of Dicrocoelium dendriticum (Trematoda) in the wild in the province of León (NW Spain)

2 pages.-- Contributed to: 11th Internacional Malacological Congress, Siena, F. Giusti & G. Manganelli (Eds.) (Siena, Italia, 1992)Dicroceliosis is a common parasitic disease in cattle and sheep in various parts of the world. The liver fluke Dicrocoelium dendriticum (Rudolphi, 1819) Loos 1899 is the species responsible for this in Spain. Its life cycle is extraordinarily complex and involves a wide range of species of land molluscs as the first intermediate hosts (I.H.) and various species of ants as the second I.H. The epidemiological nature of dicroceliosis is extraordinarily influenced by local conditions, and only in areas where the appropriate species of molluscs and ants, as well as ruminants (or other definitive hosts) come together can D. dendriticum complete its life cycle successfully. Although dicroceliosis is widespread in domestic stock and is of economic significance in the Iberian Peninsula, there are great gaps in the knowledge about its transmission. The wide variety of ecological conditions means a high number of mollusc and ant species in Spain and, particulary, in the province of León...This study was supported by the "Junta de Castilla y León (Project number 0701/89) and DGICYT (Project number PB 89 0081).Peer reviewe