Castor cake as organic fertilizer to control gastrointestinal nematodes in pasture-raised sheep / Torta de mamona como adubo orgânico para o controle de nematoides gastrintestinais em ovinos criados a pasto

Abstract Gastrointestinal parasitism is one of the factors that discourages farmers from raising small ruminants in cultivated pastures. To validate a soil treatment strategy to control the free-living stages of gastrointestinal nematodes (GIN), castor cake (CC) was used as a fertilizer on a pasture where sheep grazed on guinea grass under continuous stocking. On day zero, the pasture was divided into three paddocks, contaminated by GIN and treated, respectively, with CC divided into two applications (2CC1/2), CC in a single application (CC1) and organic compost in a single application (control). On day 21, eight GIN-free sheep were placed in each paddock. On day 58, significant differences (P<0.05) were observed: reduction of up to 66.10% in larvae.g-1 of dry mass in pastures fertilized with CC, decrease of up to 60.72% in infection rates among the animals in the groups treated with CC, higher average daily weight gain (over 185 g.day-1) and packed cell volume (over 26%) in the groups treated with CC, when compared to the control (128 g.day-1; 20.9%). In view of the results, the use of CC, mainly CC1, as a fertilizer for guinea grass pastures, under continuous stocking, proved to be promising, with 63.41% effectiveness in controlling worm infestations.

Resumo O parasitismo gastrintestinal é um dos fatores que fragiliza a exploração de pequenos ruminantes em pastagens cultivadas. Objetivando validar a estratégia de tratamento do solo para o controle dos estágios de vida livre de nematoides gastrintestinais (NGI), a torta de mamona (TM) foi utilizada como adubo, com ovinos pastejando em capim-tanzânia sob lotação contínua. No dia zero, o pasto foi dividido em três piquetes, contaminados por NGI e tratados, respectivamente, com TM parcelada em duas aplicações (2TM1/2), TM em uma única aplicação (TM1) e composto orgânico em única aplicação (testemunha). No dia 21, cada piquete recebeu oito ovinos livres de NGI. No dia 58, observaram-se diferenças significativas (P<0,05): redução de até 66,10% de larvas.g-1 de massa seca nas pastagens adubadas com TM; redução de até 60,72% da infecção dos animais nos grupos tratados com TM; ganho de peso médio diário (acima de 185 g.dia-1) e volume globular (acima de 26%) superior nos grupos tratados com TM, quando comparados com a testemunha (128 g.dia-1; 20,9%). Diante dos resultados, o uso da TM, principalmente TM1, como adubo em pasto de capim-tanzânia, sob lotação contínua, mostrou-se promissor, com eficácia de 63,41% para controlar a verminose.

Lagochilascaris minor: antibody production in experimentally infected mice / Lagochilascaris minor: produção de anticorpos em camundongos experimentalmente infectados

Lagochilascaris minor is the causative agent of lagochilascariosis, a disease that affects the neck region and causes festering abscesses, with eggs, adult parasites and L3/L4 larvae within the purulent exudates. Today, mice are considered to be intermediate hosts for the parasite. C57BL/6 mice produce immunoglobulin IgM, IgA and IgG against the crude extract of the parasite; on the other hand, antibodies produced against the secreted/excreted antigens of Lagochilascaris minor present lower levels of IgM, IgA and IgG. This is the first description of antibody detection against different antigens of Lagochilascaris minor.

Lagochilascaris minor é o agente etiológico da lagochilascariose, uma doença que afeta a região do pescoço causando abscessos exudativos com presença de ovos, parasitos adultos e larvas nos de exudatos purulentos. Hoje em dia, camundongos são considerados os hospedeiros intermediários para o parasita. Camundongos C57BL/6 produziram imunoglobulinas IgM, IgA e IgG contra o extrato bruto do parasita; por outro lado, anticorpos produzidos contra os antígenos secretados/excretados de Lagochilascaris minor apresentaram níveis mais baixos de IgM, IgA e IgG. Esta é a primeira descrição da detecção de anticorpos contra diferentes antígenos de Lagochilascaris minor.

Intestinal helminthes and/or Toxocara infection are unrelated to anti-HBs titers in seven-year-old children vaccinated at birth with recombinant hepatitis B vaccine

The aim of this investigation was to evaluate the possible effect of nematode infection on anti-HBs antibody levels in the serum of seven-year-old schoolchildren vaccinated at birth with the recombinant hepatitis B vaccine. Anti-HBs and anti HBc antibodies were evaluated in the sera of 100 schoolchildren with at least one intestinal nematode and/or a positive serological reaction for anti-Toxocara antibodies and in 95 schoolchildren without intestinal helminthiasis or serum anti-Toxocara antibodies. Both groups were from public elementary schools located on the urban periphery of Vitória, ES, Brazil. Among these 195 children, the median anti-HBs antibody titer was 31.3IU/ml and the frequency of titers less than 10IU/ml was 33.8 percent (95 percent CI: 27.1-40.4 percent). There were no significant differences between the medians of anti-HBs titers or the frequency of titers less than 10IU/ml between the groups with or without helminthes (29.5 and 32.9IU/ml and 33 and 34.7 percent, respectively; p>0.05). Even when the children with intestinal nematodes and/or anti-Toxocara antibodies and with blood eosinophil counts over 600/mm³ were compared with children without infection from intestinal nematodes and without anti-Toxocara antibodies, with blood eosinophil counts less than 400 eosinophils/mm³, these differences were not significant. None of the children presented anti-HBc antibodies. In conclusion, infections with intestinal nematodes and/or the presence of anti-Toxocara antibodies did not interfere with the anti-HBs antibody titers in seven-year-old children vaccinated at birth with the recombinant hepatitis B vaccine.

O objetivo dessa investigação foi avaliar um possível efeito de infecções por nematóides sobre os níveis de anticorpos anti-HBs no soro de escolares de sete anos de idade, vacinados ao nascer com a vacina recombinante para hepatite B. Anticorpos anti-HBs e anti-HBc foram avaliados no soro de 100 escolares portadores de pelo menos um nematóide intestinal e/ou uma reação sorológica positiva para anticorpos anti-Toxocara e em 95 escolares sem helmintíases intestinais e sem anticorpos séricos anti-Toxocara, todos matriculados em escolas primárias públicas situadas na periferia urbana de Vitória, ES, Brasil. Nas 195 crianças, a mediana dos títulos dos anticorpos anti-HBs foi 31,3UI/ml, e a freqüência de títulos inferiores a 10UI/ml foi de 33,8 por cento (IC a 95 por cento:27,1- 40,4 por cento). Não houve diferença significativa entre as medianas dos títulos de anti-HBs ou da freqüência de títulos inferiores a 10 UI/ml entre as crianças com ou sem helmintos (29,5 e 32,9 UI/ml e 33 e 34,7 por cento, respectivamente; p >0.05). Mesmo quando comparadas crianças com nematóides intestinais e/ou anticorpos anti-Toxocara com eosinófilos circulantes acima de 600/mm³, com crianças sem infecção com nematóides intestinais e sem anticorpos anti-Toxocara, com menos de 400 eosinófilos/mm³, aquelas diferenças não foram significativas. Nenhuma das crianças apresentou anticorpos anti-HBc. Em conclusão, infecções com nematóides intestinais e/ou presença de anticorpos anti-Toxocara não interferem nos títulos de anticorpos anti-HBs em crianças de sete anos de idade, vacinadas ao nascer com a vacina recombinante para hepatite B.

Intestinal nematodes and pulmonary tuberculosis

We report a significantly higher prevalence of intestinal nematodes in patients with pulmonary tuberculosis (TB) compared to a matched control group: 33/57 (57.8 percent) in patients with TB and 18/86 (20.9 percent) in the control group; OR=5.19; 95 percent CI= 2.33-11.69; p=0.000). When TB patients eosinophilia was also significantly higher among those with intestinal parasites (69.8 percent) compared to those without this condition (45.6 percent). We hypothesized that the immune modulation induced by nematodes is a factor that enhances TB infection/progression and that eosinophilia seen in TB patients is a consequence of helminth infection

Hiperinfección por Strongyloides stercolaris en portadores del virus linfotrófico humano tipo I (HTLV-I)

Se presenta una serie de siete pacientes portadores del virus linfotrófico humano tipo I (HTLV-I) con hiperinfección por S. stercolaris. Ninguno de elllos presentaba paraparesia espástica tropical/mielopatíaasociada con el HTLV-I (TSP-HAM) o leucemia/linfoma de células T del adulto (ATL). Ninguno había recibido glucocorticoides ni tenía antecedentes de transfusiones sanguíneas. Todos eran HIV (-). El diagnóstico serológico de infección por HTLV-I se realizó por los métodos de ELISA y PA, y fueron confirmados por Western Blot. El diagnóstico de estrongiloidiasis fue hecho por la prueba de Baerman en materia fecal en seis de siete pacientes, y en todos los casos por biopsia gástrica y/o duodenal. Seis pacientes provenían de la costa pacífica y el caso restante de Bucaramanga, Santander. Todos los pacientes presentaban cuadro de dolor abdominal progresivo, anorexia, náusea, vómito y diarrea. Al momento de la consulta presentaron gastritis y duodenitis crónica (por endoscopia y bipsia); cuatro de ellos presentaron infiltración gástrica y seis compromiso severo del estado nutricional. Ninguno presentó eosinofilia. Como complicaciones hubo un caso de meningitis bacteriana, uno de absceso cerebral y una septicemia por E. coli. Como conclusión se sugiere que los portadores del virus HTLV-1 pueden cursar con una pérdida selectiva de la inmunidad contra S. stercolaris. Por otro lado, se debe estudiar la posible coinfección con HTLV-I en pacientes con hiperinfección por S. stercolaris.

The eosinophils in parasitic infections

Local and peripheal eosinophilia is a common feature of many helminth infections that present large, non-phagocytable surfaces to the inmune system. The effect of the eosinophils on these organisms has been studied in the last 18 years using schistosoma mansoni, trichinella spiralis, and other helminths as models. The early infection causes a nonspecific inflammation rich in macrophages, lymphocytes and neutrophils that sets the stage for a subsequent inmune response. The predominant effector elements of the inmune response are anaphylactic antibodies, mast cells, and eosinophils. Mast cell products attract eosinophils and concentrate antibodies and complement-covered parasites by their Fc and/or C3c receptors and release oxygen radicals and/or preformed proteins on the helmith surface. The radicals alter molecules of the parasite and the proteins disrupt its tegument or cuticle. Occasionally, they may harm host cells. Eosinophils also phagocytize and harm extracellular trypanosoma cruzi and may play a role in the damage to the host heart tissue. The eosinophil response is regulated by eosinophilopoietic factors (interleukines [IL] 3 and 5, and granulocyte macrophage colony-stimulating factor) eosinophilotactic factors (C5a from complement, eosinophil chemotactic factor of anaphylaxis [ECF-A], histamine, platelet stimulating factor, and other ECFs from mast cells and basophils, and ECF from parasites), and eosinophiloactivating factors (IL-5 from Th2 lymphocytes, tumor necrosis factor from macrophages, antibodies, and complement components). Other phagocytic cells (macrophages and neutrophils) also exhibit important anti-helminthic activities

La caracterización de los antígenos de superficie del nemátodo parásito Trichinella spiralis: estudio de su participación en los mecanismos de protección y su utilidad en el diagnóstico de la triquinosis / Charaterization of surface antigens of the parasite nematode Trichinella spiralis: mechanisms of protection and use in diagnosis of trichinosis

Entre los aspectos más importantes en el estudio de la triquinosis, se encuentra el desarrollo de los métodos de diagnóstico específicos y confiables que permitan la detección oportuna de la infección, así como la identificación y caracterización de antígenos del parásito que previenen la infección. En este contexto, la caracterización de los antígenos de superficie esticosoma y de excreción secreción de la larva muscular de Trichinella spiralis, ha sido muy relevante, dada su alta inmunogenicidad prácticamente en todos los huéspedes hasta ahora estudiados. Así, durante el desarrollo de este trabajo se ha logrado identificar y caracterizar las moléculas de estos dos compartimentos de la larva muscular de T. spiralis que se han empleado tanto en la detección específica de la infección por T. spiralis (particularmente en cerdos), como en los ensayos para evaluar su potencial en la inducción de protección modelos murinos

Identification T-cell reactive antigens in Nippostrongylus brasiliensis using a cell immunoblotting technique

Antigens of the nematode Nippostrongylus brasiliensis were fractionated by SDS-PAGE under reducing conditions, transferred electrophoretically onto nitrocelluose and converted to antigen-bound nitrocellulose particles for use in vitro proliferation assays. Mesenteric lymph node cells from unfected rats were analyzed for reactivity against the fractionated antigens, revealing a range of different molecular weight antigens. Ian addition, when supernatants from these cultures were assyed for IL3, further reactive antigens wee detected. The results demonstrated that these approaches are useful for the identification of T-cell reactive components of a complex mixture of parasite antigens in helminth infections, where the cellular nature of protection is not well defined

Humoral immune response of Balb/c mice to larval and adult worm antigens of Angiostrongylus malaysiensis.

The development of Angiostrongylus malaysiensis in Balb/c mice and the humoral response due to it were studied by using the enzyme-linked immunosorbent assay (ELISA) with adult worm and L3 antigens. The worms recovered from mice were seen in the brain tissue only, they failed to migrate to the lung as in the normal host (rats). The antibody titres of sera from infected mice, showed similar patterns in response to L3 antigen and to adult worm antigen. However, the highest antibody response could be detected by L3 antigen in the early period after infection while the adult worm antigen detected a higher response in the later stages of development.

Demonstration of species-specific antigens of Gnathostoma spinigerum, a preliminary attempt.

An attempt was made to demonstrate the presence of species-specific antigens for Gnathostoma spinigerum advanced third-stage larvae (GsAL3) in a rabbit receiving weekly immunization with GsAL3 for seven weeks. The homologous and heterologous antibodies against GsAL3 and G. doloresi adult worm (Gd) antigens were initially detected by immunoelectrophoresis (IEP) and ELISA after the second immunization, and their levels were gradually increased with the number of immunizations. Though cross-reactivity between GsAL3 and Gd were shown with both tests, species-specific antibodies for the homologous antigens were demonstrated. After cross-absorption of rabbit hyperimmune serum was collected after the seventh immunization, seven 'putative' species-specific precipitin bands of GsAL3 were identified. The ELISA values of the rabbit hyperimmune serum showed 50% inhibition after absorption with 0.7 micrograms/ml of homologous GsAL3 antigens as opposed to 1.0 micrograms/ml of the heterologous Gd antigens.

Influencia de la edad de los veronicélidos en la infección con Angiostrongylus costaricensis / Influence of the age of Veronicellid slugs in Angiostrongylus costaricensis infection

In Costa Rica, Veronicellid slugs are the most important hosts for Angiostrongylus costaricencis. Apparently, these molluscs develop a resistant mechanism after being exposed to the infection. In naturally infected slugs, the higher infection rates were found in larger slugs, but they usually bear few larvae. larger number of larvae were found in medium sized molluscs. Experimental infection in laboratory breed slugs produced an amebocytic reaction around developing larvae; later, the formation of a fobrotic capsule is observed. When there is a second infection, cell reaction is stronger and the larvae show degenerativesigns. This cell-mediated resistant mechanism seems to explain why the biggest moluscs, although more probably exposed to infection, bear fewer larvae.

Antibody responses in human gnathostomiasis.

Sera from 4 patients with parasitologically confirmed gnathostomiasis and from 18 healthy individuals were studied by SDS-PAGE and Western blot analysis using radioiodinated protein A to detect antibody responses against crude aqueous somatic extract of advanced third stage larvae of Gnathostoma spinigerum (L3G). It was found that the L3G extract was highly complex, comprising of more than 40 polypeptides among which more than 20 components were antigenic in human. The relative M.W. of the proteins ranged from 13 kd to 150 kd with the major antigenic bands at 150, 135, 120, 94, 84, 82, 72, 55, 54, 49, 43, 38, 35, 32 and 28 kd. All 4 sera from gnathostomiasis patients gave almost an identical pattern of reactivities against the L3G antigens whereas sera from the normal individuals gave much lower reactivities against the L3G antigen of M.W. 38 kd and, in certain individuals, those of 49 and 43 kd. The present findings suggest that the serum antibody response against the parasite is specific and may be useful in a specific or a confirmed immunodiagnosis of human gnathostomiasis.

Detection of humoral immune response to Gnathostoma spinigerum in mice.

The humoral immune response to early third stage larvae (EL3) and advanced third stage larvae (AL3) of Gnathostoma spinigerum infection was studied in mice by Ouchterlony gel diffusion technique. The antibodies was detected at week 3 in mice infected with EL3 and remained up to week 10 after infection. Highest positive sample of sera were demonstrated at week 4 to week 7. Similar results were obtained from AL3 infected sera except the antibodies was found and disappeared earlier (week 2 to week 6). G. spinigerum larvae recovery from mice in both groups showed that the number of advanced third stage larvae located in muscle correlated to the peak of positive sera. No cross reaction was observed on positive sera of G. spinigerum and antigens of A. cantonensis, P. siamensis, T. spiralis, O. viverrini and A. ceylanicum. Cross reaction was shown on the G. spinigerum antigen against rat sera with angiostrongyliasis and bandicoot sera with paragonimiasis.

Capillaria hepatica: alguns aspectos imunopatológicos da infecçäo espúria e da infeçäo verdadeira / Capillaria hepatica: some immunopathologic aspects of spurious and true infection

A fim de se observar uma possível proteçäo conferida pela infecçäo espúria contra uma infecçäo verdadeira por Capillaria hepatica, camundongos foram inoculados com ovos näo embrionados (infecçäo espúria) e, posteriormente, com ovos embrionados (infecçäo verdadeira). Anticorpos específicos da classe IgG, detectados por este imunoenzimático (ELISA), mostraram-se elevados a partir da segunda semana do experimento. O teste de hipersensibilidade cutânea tardia resultou negativo. O exame das lesöes do fígado, assim como a contagem de ovos, utilizados como parâmetros para comparaçäo entre os grupos de animais estudados, näo apresentaram variaçäo significativa indicando que a imunidade humoral induzida pela infecçäo espúria näo tem potencial protetor

Induction of protective immunity against infection by Angiostrongylus cantonensis in rats.

Attempts were made to induce acquired immunity against Angiostrongylus cantonensis infection by immunizing rats with somatic (L3S) and metabolic (L3ES) antigens from third-stage larvae and with somatic antigen from adult female worms (FACE) via either a combined intraperitoneal and oral (IP-OR-OR) or subcutaneous (SC-SC-SC) route. The most effective mean in inducing protection was the administration of L3S by the IP-OR-OR route, as judged from reduced mortality, prolonged survival periods and/or reduced worm burdens. Such a protocol reduced mortality to below 20% of the unimmunized controls. The worm burden of the L3S-immunized rats was only about 25% of the control value and the survival period was at least double. However, judging from gross morphology, the absence of stunted growth and unimpaired ficundity of the worms that developed into adult stage, it appears that those worms that survived had normal development. The latter observation is in contrast to that noted with FACE immunization which seemed to affect also the growth and development of worms that survived into adult stage.

The biology of Angiostrongylus cantonensis larvae in immune rats.

Rats acquired protective immunity to Angiostrongylus cantonensis after a single infection with 50 infective larvae. Immunity was stronger after subsequent infections. Fewer worms were recovered which were shorter and produced fewer progeny after secondary and tertiary infections. However, the growth of A. cantonensis during the early developmental stages in the brain and the ability of the young adult parasites to migrate to the lungs was not affected in the immune host.

Effect of immunization with metabolic antigens on experimental infection of rats with Angiostrongylus cantonensis.

Immunization of rats with excretions and secretions from an in vitro culture fluid (ES antigens) of adult female Angiostrongylus cantonensis markedly enhanced their resistance to infection by third-stage larvae. Mortality rate, survival period, worm development and worm recovery, determined after a lethal challenge with infective larvae, were compared in immunized and unimmunized animals. With regard to these criteria, the results obtained with animals that had been immunized with ES antigens from adult males were found to be indistinguishable from those of the unimmunized controls. On the contrary, those immunized with ES antigens from adult females had lower mortality rate, increased survival period, and lower worm burden. Both male and female worms recovered from brain and mature adults recovered from pulmonary arteries of rats that had been immunized with female ES antigens were also found to be stunted.