859 research outputs found
In vitro effects of three woody plant and sainfoin extracts on two parasitic stage of 3 parasitic nematode species
Most studies on the effects of tanniferous plants on nematodes have examined forages but have neglected the woody plants. Therefore, in vitro effects of extracts from 3 woody plants (Rubus fructicosus, Quercus robur, Corylus avellana) have been tested on trichostrongyles and compared to sainfoin, a legume forage. Because some in vivo results indicated that the effects of tannins differed depending on the parasitic species and/or stages, the effects were measured on third-stage larvae (L3) and adult worms of Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus colubriformis. The effects of plant extracts varied according to the plant sources, the parasite species and stages. For the woody plants, significant inhibitory effects were obtained on both stages of abomasal species. Results for T. colubriformis were more variable. Effects of sainfoin extracts were significant on T. colubriformis and H.contortus L3, and on abomasal adult worms. In order to assess the implications of tannins, polyethylene glycol (PEG), an inhibitor of tannins, was added to hazel tree, oak and sainfoin extracts. Without PEG, significant inhibitory effects on L3 and adult worms were confirmed. After addition of PEG, the larval migration and motility of adult worms were restored in most cases. These results confirm variations in effects depending on factors related to plants or parasites and suggest that tannins are partly responsible for the effects
Effects of sainfoin hay on gastrointestinal infection with nematodes in goats
EFFECTS OF SAINFOIN HAY ON GASTROINTESTINAL INFECTION WITH NEMATODES IN GOATS
Effects of the repeated distribution of sainfoin hay on the resistance and the resilience of goats naturally infected with gastrointestinal nematodes
Due to the high prevalence of anthelmintic resistance in goats, the need to explore novel approaches to control nematodes and
to reduce the exclusive reliance on chemotherapy is strongly demanded in this host species. In sheep, several studies have shown
that the consumption of tannin-rich legume forages was associated with positive effects on host resilience and resistance to
parasite infection. In goats, studies on such interactions between tanniferous plants and nematode infections remain few. The
objectives of the current study were to examine under natural conditions the effects of consumption of sainfoin hay by goats on
the parasite populations and on host resilience.
Eighteen adult cull goats naturally infected with Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus
colubriformis were used in the study. At the start of the assay, the goats were allocated into two groups, balanced according to
weight and the levels of egg excretion. The two groups grazed separate pastures for 3 months with similar stocking rates. Goats
from group S received each month indoors, for 7 days, sainfoin hay and control goats (group C) received hay of ryegrass. The
diets in both groups were made isoenergetic and isoproteic and the refusals measured. Individual parasitological and
pathophysiological measurements were performed fortnightly in order to compare host resistance and resilience. At the
end of the study, five goats per group were necropsied. The distribution of sainfoin was associated with: (1) a higher consumption
of hay; (2) significant, lower levels of nematode egg excretion which was associated with a decrease in worm fertility but no
change in worm population; however, the number of intestinal worms was reduced by 50% in group S; (3) a better host
resilience. In particular, after 2 months of grazing, two control goats died and half of the remaining animals needed to be treated
whereas this was not the case in group S. These differences were related to significant changes in pepsinogen and phosphate
values (PCV) but not in pepsinogen and phosphate concentrations. These results demonstrate that a repeated distribution of
sainfoin hay to grazing goats might be beneficial in regard of pasture contamination and host resilience. They suggest that
administration of sainfoin hay might represent a valuable alternative and adjunct to reduce nematode infections in dairy goat flock.
# 2004 Elsevier B.V. All rights reserved
Effects of condensed tannins on goats experimentally infected with Haemonchus contortus.
Although the use of tanniferous plants or condensed tannins as an alternative to anthelmintics to
control gastrointestinal nematodes has been largely documented in sheep, studies remain scarce in
goats. The objective of this study was therefore to assess the possible impact of condensed tannins
in goats infected with adult Haemonchus contortus. Two groups of cull goats were experimentally
infected with 10.000 L3 of H. contortus. After 4 weeks, quebracho extracts, representing 5%
of the diet DM, were administered for 8 days to one of the two groups. Goats of the second
group remained as controls. One week after the end of quebracho administration, the goats were
euthanised. Individual egg excretion and pathophysiological parameters were measured weekly
during the study. At the end of the study, worm counts were assessed and histological samples
from the abomasa were taken to count the numbers of mucosal mast cells, globule leukocytes
and eosinophils. The administration of tannins was associated with a significant decrease in egg
excretion, which persisted until the end of experiment. This reduction was not associated with
any difference in worm number but with a significant decrease in female fecundity. No significant
changes in the mucosal density of the three inflammatory cell types were detected between the
two groups. These results indicate that the major consequence of tannin consumption in goats is a
reduction in worm fecundity and egg output, which does not seem related to significant changes in
the local mucosal response
Effets des tanins condensés et des plantes à tanins sur les strongyloses gastro intestinales chez le mouton et la chèvre
Les strongyloses gastro-intestinales sont une des pathologies majeures chez les petits ruminants élevés à l’herbe. Elles peuvent entraîner des pertes de production importantes. Le moyen usuel de lutte contre ces parasitoses est l’utilisation des anthelminthiques. Cependant, plusieurs problèmes se posent quant à leur utilisation. Premièrement, les résistances aux anthelminthiques au sein des populations de vers sont de plus en plus fréquentes, et particulièrement chez les caprins. Deuxièment, en lactation, seules certaines molécules sont autorisées. De plus, les consommateurs se montrent de plus en plus réticents à l’emploi de molécules chimiques en élevage. Il y a donc un réel besoin de trouver des méthodes alternatives ou complémentaires aux anthelminthiques afin de maîtriser ce parasitisme digestif.
L’utilisation de champignons nématophages, une gestion raisonnée du pâturage ou encore un apport de protéines au sein de l’alimentation sont des méthodes pouvant aider à mieux gérer les infestations parasitaires. Une autre solution alternative envisageable est l’emploi des tanins condensés. Différentes études menées chez les ovins et les caprins montrent que l’apport de tanins condensés pourrait constituer un moyen de lutte efficace contre les strongles gastro-intestinaux
Effects of distribution of quebracho extracts on experimental Haemonchus contortus infections in goats
The effects of tannins on adult populations of Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta
in goats are characterised mainly by a decrease in egg excretion without any significant changes in worm number. In contrast,
the impact of tannins on T. colubriformis or T. circumcincta third-stage larvae (L3) is associated with a significant reduction in worm
establishment. The objective of the present study was to examine the effects of quebracho extract tannins on H. contortus L3. The
consequences of consumption of sainfoin hay were also examined.
Twenty-one naı¨ve kids were divided into three experimental groups. Group Q received quebracho extract and group S received
sainfoin hay from days D3 to D5. Group C remained as an infected control group. All kids received 1500 L3 H. contortus on D0, D1
and D2. On D18, post-infection, the kids were slaughtered and the worm populations compared in the different groups. Compared
to the control values, the worm counts decreased, respectively, by 33% and 38% in groups Q and S but the differences were not significant.
No differences were found in pathophysiological measurements between the three groups. The results confirm differences in
tannin effect according to nematode species but not parasitic stage
Interactions between nutrition and gastrointestinal infections with parasitic nematodes in goats
Parasitic nematodes of the digestive tract remain one of the main constraints to goat production both in temperate and tropical
countries. The usual mode of control of these gastrointestinal nematodes (GIN) based on the repeated use of anthelmintics
is now strongly questioned because of the increasing development of resistance to these molecules. Among the alternative
methods to anthelmintics currently available, the manipulation of host nutrition in order to improve the host resistance and/or
resilience to parasitic infections seems to represent one of the most promising options to reduce the dependence on conventional
chemotherapy and to favour the sustainable control of gastro intestinal nematode infections. This paper will review the available
information on the interactions between nutrition and nematode parasitism in dairy or meat goats both in temperate and tropical
conditions. It will refer to quantitative aspects of the diet (influence of the protein and/or energy parts) as well as to qualitative
components (effects of plant secondary metabolites on worm biology) and will discuss the specificities of goats in regard of
theses interactions
Gestion non chimique du parasitisme par les nématodes chez les petits ruminants.
L‘agriculture biologique est particulièrement touchée par le parasitisme en raison de son utilisation intensive du pâturage, alors que les traitements anthelminthiques y sont
très encadrés.Cet article propose plusieurs méthodes naturelles de lutte contre les nématodes
Common variable immunodeficiency. Epidemiology and clinical manifestations in 69 patients.
La inmunodeficiencia común variable (IDCV) se caracteriza por una alteración en la producción de anticuerpos y una mayor susceptibilidad a infecciones por bacterias extracelulares capsuladas, principalmente del tracto respiratorio. Analizamos las caracterÃsticas clÃnicas de 69 pacientes, evaluados en un perÃodo de 10 años en tres centros de la ciudad de Buenos Aires. Al inicio del estudio se encontraban en seguimiento 14 pacientes y al finalizar 60; la mayorÃa fueron derivados por infecciones o hipogammaglobulinemia, y casi la mitad con diagnóstico establecido de inmunodeficiencia. Sesenta y cinco (94.2%) pacientes presentaron infecciones por gérmenes capsulados, cuatro (6.1%) sepsis y dos tuberculosis. La edad promedio de comienzo de los sÃntomas infecciosos fue de 18.1 años, la edad promedio al momento del diagnóstico fue de 29.6 años y el retraso diagnóstico de 11.9 años. En 41 (59.4%) pacientes se registró el antecedente de diarreas recurrentes o crónicas. En 22 (31.9%) se diagnosticaron 13 enfermedades autoinmunes, siendo las más frecuentes las hematológicas y el hipotiroidismo. Ocho pacientes tuvieron linfoproliferación policlonal histológica, cuatro (5.8%) como enfermedad granulomatosa de hÃgado, laringe y piel, y cuatro como neumonÃa intersticial linfoidea (NIL). Diecinueve (27.5%) pacientes presentaron esplenomegalia y 23/57 (40.3%) imágenes sugestivas de procesos granulomatosos o linfocÃticos en la TAC de tórax (incluidos los 4 con NIL). Tres (4.3%) pacientes desarrollaron linfoma B, cuatro (5.8%) adenocarcinoma de estómago y uno cáncer de mama. El estudio tuvo una mediana de seguimiento de 54 meses, rango 1-353 y durante el perÃodo del mismo murieron cuatro pacientes (5.8%).Common variable immunodeficiency (CVID) is characterized by an impaired antibody production and an increased susceptibility to recurrent infections of the respiratory tract, mainly by extracellular encapsulated bacteria. We analyzed the clinical characteristics of 69 patients evaluated over a period of 10 years at three centers in the city of Buenos Aires. At the onset of the study 14 patients were on follow up, and at its end the number of patients reached to 60. Most of them consulted for infection or hypogammaglobulinemia and nearly half had an established diagnosis of immunodeficiency. Sixty-five (94.2%) patients had infections by encapsulated bacteria, four (6.1%) sepsis and two tuberculosis. The average age of onset of infectious symptoms was 18.1 years; the average age at diagnosis was 29.6 years and the delay to diagnosis 11.9 years. Forty one (59.4%) patients reported a history of recurrent or chronic diarrhea. In 22 (31.9%) 13 autoimmune diseases were diagnosed, being the most frequent the hematological disorders and hypothyroidism. Eight patients had histological polyclonal lymphoproliferation, four (5.8%) with granulomatous disease affecting the liver, the larynx and/or the skin; and four as lymphoid interstitial pneumonitis (LIP). Nineteen (27.5%) patients had splenomegaly and 23/57 (40.3%) images suggestive of lymphocytic or granulomatous processes (including the 4 with LIP) in the chest CT. Three (4.3%) patients developed B cell lymphoma, four (5.8%) stomach adenocarcinoma and one breast cancer. The study had a median follow-up of 54 months, range 1-353 and four patients (5.8%) died during the follow up.Fil: Fernández Romero, Diego S.. Hospital Britanico. Serv. de Alergia E Inmunologia Clinica; ArgentinaFil: Juri, MarÃa C.. Hospital Britanico. Serv. de Alergia E Inmunologia Clinica; ArgentinaFil: Paolini, MarÃa V.. Hospital Durand; ArgentinaFil: Malbran, Alejandro. Hospital Britanico. Serv. de Alergia E Inmunologia Clinica; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentin
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