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1.
Nat Prod Res ; 36(23): 6091-6095, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35245980

RESUMO

Mushrooms have health benefits, including anti-tumoral properties. We evaluated the cytotoxic and cell death induction effects of water-soluble extracts of Pleurotus ostreatus and Pleurotus eryngii mycelium in the cervical cancer cell lines HeLa (HVP18+) and SiHa (HVP16+) as well as the non-tumoral cell line HaCaT. Both Pleurotus extracts presented similar protein patterns from 190 to 10 kDa and displayed protease activity on a gelatine substrate. The mycelium extracts of both Pleurotus strains induced a dose-dependent cytotoxic effect on HPV+ cells IC50 65 µg), whereas HaCaT cells were less susceptible (IC50 90 µg). The cytotoxic effect at the IC50 concentration was not associated with apoptosis, the activation of Caspases-3/7 was not significantive; only P. eryngii induced a moderate (1.2-fold) increase in SiHa cells. Pleurotus extracts induced autophagy, mainly in SiHa cells (4.3-fold). Neither extracts induced changes in p53 protein expression, suggesting that the cytotoxic effect could be due to p53-independent pathways.


Assuntos
Antineoplásicos , Pleurotus , Neoplasias do Colo do Útero , Feminino , Humanos , Pleurotus/química , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Micélio/química , Células HeLa , Antineoplásicos/farmacologia , Antineoplásicos/análise , Apoptose
2.
Trop Anim Health Prod ; 54(2): 95, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35138496

RESUMO

The objective of this study was to evaluate an n-hexane extract of Artemisia cina (Acn-h) as a natural anthelmintic treatment for periparturient goats naturally infected with the nematodes Haemonchus contortus and Teladorsagia circumcincta. A total of 200 periparturient Alpine and Nubian goats were used. Deworming criteria were based on the following parameters: fecal egg account (epg), ocular mucosa color (OMC), and body condition (BC). A previous analysis using coprocultures of the flock revealed the presence of H. contortus (80%) and T. circumcincta (20%). The Acn-h contained two new compounds identified by mass spectrometry data as isoguaiacin and norisoguaiacin at 284.14 and 315 m/z. The lethal effects of Acn-h at 0.5, 1, 2, and 4 mg/mL on H. contortus adult stages were 31.6, 66.5, 81.3, and 86.9%, respectively (p < 0.05), showing similar efficacy at 2 and 4 mg/mL with albendazole (positive control group). Then, two experimental groups, with 100 goats in peripartum in each, were distributed randomly and treated at day 0 as follows: group 1 = 4 mg/kg of Acn-h as single oral dose, and group 2 = control group, treated with water (as a placebo). The epg, OMC, and BC parameters were recorded at 0 (periparturient period), 7 (birth period), and 23 (postpartum) days and analyzed using a completely randomized design with Duncan's test for comparison of means and analysis of variance. The following epg reductions were recorded in the Acn-h-treated group as follows: 20.1 ± 34.4 and 31.7 ± 38.2% at days 7 and 23 compared to the control group. During the whole experiment, no significant differences in OMC or BC were observed in relation to the control group, excepting at day 23 (p < 0.05) for BC in the group treated with A. cina. Thus, Acn-h can be a useful natural alternative tool for the control of the nematodes H. contortus and T. circumcincta in periparturient goat flocks.


Assuntos
Anti-Helmínticos , Artemisia , Doenças das Cabras , Hemoncose , Haemonchus , Animais , Anti-Helmínticos/uso terapêutico , Fezes , Feminino , Doenças das Cabras/tratamento farmacológico , Cabras , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Hexanos , Contagem de Ovos de Parasitas/veterinária
3.
Vet Parasitol ; 298: 109512, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34271321

RESUMO

The excretory/secretory (E/S) products released by infective transitory larvae (xL3) of Haemonchus placei have an important biological function in stimulating immune mechanisms during the invasive process. Our objective was to analyse the modulatory activity of 15 and 70 kDa E/S products from H. placei xL3. Both E/S products were collected from xL3in vitro cultures at 24 and 72 h. Proteins were confirmed by SDS-PAGE, and the corresponding spots were elicited by gel isoelectrofocusing (IEF) and characterised by mass spectrometry. Additionally, flow cytometry of CD4+/γδ+ T cells and immune gene expression were performed by proliferation assays using each E/S product to stimulate lymphocyte and peripheral blood mononuclear cells (PBMCs) from non-infected calves. The IEF results displayed two spots of 7.0 and 5.7 pI for the 15 and 70 kDa products, respectively. Additionally, 29 and 17 peptides from the 15 and 70 kDa E/S products, respectively, were identified with the hypothetical neurotransmitter and enzymatic functions necessary for larval development. The relative expression displayed upregulation of IL4, 5, 6, 8, 10, 13, IFNγ, and FCεR1A genes (from 2.0- to 17.6-fold, p < 0.05) stimulated by the 15 and 70 kDa proteins, indicating specific genes against haemonchosis. Although the percentage of median florescence intensity (MFI%) of CD4+/γδ+ T cells did not change for both E/S products compared to the negative control and concanavalin-A stimulated cells as the positive control (p > 0.05), the 15-kDa protein reduced the levels of both T cells, and the 70-kDa proteins increased the γδ+ cells slightly. Additionally, there was increased PBMCs proliferation by the 70 kDa proteins (p < 0.05), denoting the biological role of other immune cells. The 15 and 70 kDa protein E/S products from H. placei xL3 showed modulation of the immune response, and although more studies are required, they indicate important functions in the host/parasite interaction.


Assuntos
Antígenos de Helmintos , Haemonchus , Larva , Leucócitos Mononucleares , Linfócitos , Animais , Antígenos de Helmintos/farmacologia , Bovinos , Haemonchus/química , Interações Hospedeiro-Parasita/imunologia , Fatores Imunológicos/farmacologia , Larva/química , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia
4.
Acta Parasitol ; 66(3): 938-946, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33721186

RESUMO

PURPOSE: (1) To assess the in vitro activity of Artemisia cina against Haemonchus contortus L3 (HcL3) and in transitional (L3-L4) larvae (HcTrL3-L4); (2) to quantify the relative expression of the Hc29 gene in HcTrL3-L4 exposed to the A. cina n-hexane extract; and (3) to assess the anthelmintic activity (AA) of the A. cina organic extracts in gerbils artificially infected with H. contortus (HcArt/inf/gerbs). METHODS: The in vitro assay was carried out in 96-well microtitration plates. The following A. cina extracts: ethyl acetate (Ac-EtOAcEx), n-hexane (Ac-n-HexEx), and methanol (Ac-MethEx) were assessed at 1 and 2 mg/mL against HcL3 and HcTrL3-L4 at 24 h exposure. Relative expression of the Hc29 gene in HcTrL3-L4 was obtained by RT-PCR. For assessing the AA, six groups of five HcArt/inf/gerbs were used. Groups were treated orally with 4 mg/kg BW of A. cina extracts. Five days after treatment, the gerbils were necropsied and nematodes counted. RESULTS: The highest in vitro activities (75 and 82.6%) were shown by Ac-n-HexEx at 1 and 2 mg/mL, respectively. For HcTrL3-L4 the highest in vitro activities (69 and 23%) were shown by Ac-n-HexEx and isoguaiacine at 0.625 mg/mL, respectively. Also, upregulation of H. contortus Hc29 gene by 13- and 80-fold (p < 0.01) was observed on the HcTrL3-L4 stage after exposure to Ac-n-HexEx extract and isoguaiacine at 0.078 mg/mL, respectively. Reduction percentage was 100% in HcArt/inf/gerbs treated with Ac-n-HexEx. CONCLUSIONS: We conclude that the Ac-n-HexEx and isoguaiacine compound had anthelmintic efficacy against H. contortus and L3 and HcTrL3-L4.


Assuntos
Anti-Helmínticos , Artemisia , Hemoncose , Haemonchus , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Antinematódeos/farmacologia , Antinematódeos/uso terapêutico , Gerbillinae , Hemoncose/tratamento farmacológico , Hemoncose/veterinária , Haemonchus/genética , Larva , Extratos Vegetais/farmacologia
5.
Vet Immunol Immunopathol ; 234: 110218, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33667946

RESUMO

The immune response and phenotypic characteristics of Pelibuey lambs were analysed after the induction of a Haemonchus contortus trickle infection. Male lambs (n = 29; 20 kg live weight) were infected with 100 H. contortus infective larvae per kg of live weight on day 3, 5 and 7 of the experiment. The number of eggs per gram (epg), seven haematological parameters and the immunoglobulin A (IgA) level were analysed for 56 experimental days. In addition, histopathological samples from the fundic abomasal region and the relative expression of 10 immune-related genes from 15 infected and three non-infected lambs were analysed at day 0 and 49 of the experiment. The epg count and some haematological parameters (leucocytes, red blood cells, haemoglobin and total protein) with statistically significant differences (P < 0.01) were used to identify nine resistant and 20 susceptible lambs (1166 ±â€¯1071 and 3171 ±â€¯1463 epg, respectively). Moreover, acute infiltration of immune cells and parasitic granuloma formation were observed in susceptible lambs; the resistant group had moderate inflammatory cell infiltration. With respect to relative gene expression, resistant lambs showed upregulation (P < 0.001) of 10 genes, from 2.2 to 15.99 fold. Moreover, there was a strong indirect correlation (P < 0.05) between the epg count and interleukin 5 (IL5) gene expression. By contrast, there was an average 0.34 fold downregulation in nine of the immune-related genes (P ≤ 0.05) in susceptible lambs (the only exception was Fc fragment of IgE receptor Ia [FCER1A] upregulation). In addition, there was a direct correlation (P ≤ 0.05) between the epg count and the expression of IL8, which encodes an inflammatory chemokine. In conclusion, this study showed differential IL5 and IL8 gene expression during haemonchosis in resistant and susceptible Pelibuey lambs, respectively, together with a variable immune response based on histopathological and haematological parameters.


Assuntos
Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/veterinária , Hemoncose/imunologia , Hemoncose/veterinária , Haemonchus/imunologia , Imunidade , Animais , Suscetibilidade a Doenças/parasitologia , Fezes/parasitologia , Expressão Gênica , Hemoncose/parasitologia , Masculino , Contagem de Ovos de Parasitas , Ovinos/genética , Ovinos/imunologia , Ovinos/parasitologia , Doenças dos Ovinos/imunologia , Carneiro Doméstico
6.
J Med Food ; 24(3): 310-318, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32730102

RESUMO

Sheep haemonchosis is a disease that causes anemia, diarrhea, weight loss, low production, and even death of young animals. This represents a negative economic impact on the livestock sector. For decades, chemicals have been used to control this parasitic disease; however, cases of anthelmintic resistance have increased around the world. For this reason, the search for control alternatives is necessary. Several studies have shown that edible mushrooms of Pleurotus genus have different medicinal properties, including nematicidal activity. In this study, the chromatographic fractionation of the hydroalcoholic extract of fruiting bodies Pleurotus djamor was carried out to identify and isolate the metabolites responsible for nematicidal activity. From the fractionation of the extract, the fraction PdR2 and the subfraction PdB were obtained, which were evaluated against Haemonchus contortus under in vitro conditions. The nematicidal effect of the fraction PdB in gerbils infected artificially with H. contortus was evaluated. Finally, the analysis of the PdB fraction by gas chromatography-mass spectrometry and nuclear magnetic resonance was carried out. The results showed that the PdB had 100% of egg hatching inhibition from 5 mg/mL. Regarding larvicidal activity, it presented >97.2% from 24 h to 20 mg/mL. The in vivo evaluation of the PdB fraction showed a reduction of H. contortus larvae of 92.56%. The compounds present in this fraction were the mixture of allitol and an unidentified terpene in a ratio of 9:1. The PdB fraction is a potential alternative for the control of H. contortus, where allitol and a terpene could be responsible for nematicidal activity.


Assuntos
Anti-Helmínticos , Haemonchus , Pleurotus , Animais , Anti-Helmínticos/farmacologia , Larva , Extratos Vegetais/farmacologia , Ovinos
7.
Vet Parasitol ; 289: 109325, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33296807

RESUMO

The analysis of the immune gene expression was performed in Zebu × Holstein calves with resistant and susceptible phenotypes naturally infected with Cooperia punctata. Fourteen calves of 4 months old were grazed for 11 weeks under a tropical climate. The parasitic infection showed an average epg value of 1055 ± 1155 and an IgG optical density of 0.814 ± 0.0.037 with statistic differences among the different weeks (p < 0.05), and a pcv value of 24 ± 2.0 % (p > 0.05). High variation in epg value was observed, between 7 ± 7.14 and 4657 ± 1886, and, based on these differences; the infected hosts were classified as five resistant calves with epg ≤ 200 and nine susceptible calves with epg ≥ 300. Moreover, IgG levels displayed statistical differences between resistance and susceptible calves to C. punctata infection. The immune gene expression was analysed in three resistant and susceptible calves, respectively. Nine cytokine genes and the FCεR1A receptor were analysed at the 3rd and 11th weeks post-infection. In the first period upregulation was found, from 2.19- to 9.45-fold, (p < 0.05) for IL-2, -5, - 6, -10, TGF-ß and FCεR1A in the resistant group; the expression was decreased at the 11th week with low level of IgG. In contrast, downregulation for susceptible calves was found for nine immune genes and upregulation for INF-γ in both periods together with increased IgG levels. In conclusion, immune gene expression was regulated at the begging infection of C. punctata in resistant grazing calves. In contrast, suppression of important genes was involved in calves susceptible to C. punctata.


Assuntos
Doenças dos Bovinos/parasitologia , Regulação da Expressão Gênica/imunologia , Predisposição Genética para Doença , Infecções por Rhabditida/veterinária , Animais , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/imunologia , Citocinas/genética , Citocinas/metabolismo , Fezes/parasitologia , Contagem de Ovos de Parasitas , Rabditídios , Infecções por Rhabditida/tratamento farmacológico , Infecções por Rhabditida/imunologia
8.
Vet Parasitol Reg Stud Reports ; 21: 100422, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862901

RESUMO

We analysed the immune response involved in sheep naturally infected with gastrointestinal (GI) nematodes. Fifteen Pelibuey lambs were grazed in paddocks contaminated with GI nematodes for 13 weeks. To assess the infection, the number of eggs per gram (epg) and the percentage of packed cell volume (pcv) were evaluated. Blood and abomasal tissue samples were collected at week 8 post-infection to analyse the expression levels of IL-4, IL-5, IL-6, IL-8, IL-13, TGF-ß and FCεR1A genes. The nematode Haemonchus contortus was the main species identified. In addition, two groups of lambs were classified based on the x ± SE of epg and pcv values: G-1, with 151 ± 28 and 29 ± 0.33%, respectively, and G-2, with 475 ± 59.5 and 26 ± 0.38%, respectively. For G-1, upregulation of IL-4, IL-8, IL-13, TGF-ß and FCεR1A genes from 2.42- to 14.99-fold was observed in blood and abomasal tissue samples (p > .05), and IL-5, IL-8 and TGF-ß genes had significant gene expression levels in blood (p < .05). For G-2, moderate gene expression levels, ranging from 1.22- to 3.45-fold, were observed in abomasal tissue (p > .05), and the IL-5 gene presented significant gene expression in blood (p < .05). Strong positively correlated values (r) between pcv and IL-4, IL-8 and TGF-ß genes were observed in G-1. In contrast, significant negative correlations between epg and IL-4, IL-5 and FCεR1A genes indicate acute infection for G-2. Our results suggest that IL-4, IL-5, IL-13, TGF-ß and FCεR1A genes are important modulators of GI nematode infections of Pelibuey lambs.


Assuntos
Gastroenteropatias/veterinária , Hemoncose/veterinária , Imunidade , Infecções por Nematoides/veterinária , Doenças dos Ovinos/imunologia , Animais , Gastroenteropatias/imunologia , Gastroenteropatias/parasitologia , Hemoncose/imunologia , Hemoncose/parasitologia , Haemonchus , México , Infecções por Nematoides/imunologia , Infecções por Nematoides/parasitologia , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico , Clima Tropical
9.
Mol Biochem Parasitol ; 238: 111281, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32434064

RESUMO

The objective of this study was to analyze the mRNA transcription levels of ten functional genes of P-glycoproteins (P-gp) in free life stages, eggs and infective larvae (L3) and in endoparasitic stages, fourth larval stage (L4) and adult males of two native isolates of Haemonchus contortus: resistant and susceptible to IVM. The IVM resistant isolate was obtained from sheep naturally infected with H. contortus, and the susceptible isolate (with no pressure to IVM) conserved since 1990. The lethal effect of IVM was evaluated under in vitro conditions, which showed significant differences between susceptible and resistant H. contortus L3 isolates (P < 0.01). The IVM susceptible isolate revealed a lethal effect of 79.22% at 11.42 mM, whereas that resistant isolate showed no lethal effect at any of the four assessed concentrations (1.43, 2.85, 5.71 and 11.42 mM) of IVM. The expression levels of ten Hco-pgp genes (1, 2, 3, 4, 9, 10, 11, 12, 14, and 16) were evaluated in the resistant isolate of H. contortus and compared to the susceptible isolate (as control), using two constitutive genes (GAPDH and ß-tubulin). Up-regulation at two statistical significant values (P ≤ 0.05, 0.1) was the criterion to associate IVM resistance with the free life and endoparasitic stages of H. contortus. The expression levels in H. contortus adult nematodes showed 5.64 to 127.56-fold increase for Hco-pgp genes 1, 9, 12, 14, and 16, followed by an increase for Hco-pgp-2 (49.75-fold) and Hco-pgp-10 (106.40-fold) in L4, and for Hco-pgp-16 (2.90-fold) in eggs (P ≤ 0.05). In addition, high expression levels with P < 0.1 were detected in H. contortus L3, L4, and adults for Hco-pgp genes 1, 4, 11, 12, and 16, with changes ranging from 2.17 to 29.72-fold. In conclusion, the highest expression was observed in the adult stage of H. contortus, and the most frequent gene with a significant P-value was Hco-pgp-16, revealing it plays an important role in IVM resistance.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Anti-Helmínticos/farmacologia , Resistência a Medicamentos/genética , Haemonchus/efeitos dos fármacos , Proteínas de Helminto/genética , Ivermectina/farmacologia , RNA Mensageiro/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Expressão Gênica , Hemoncose , Haemonchus/genética , Haemonchus/metabolismo , Proteínas de Helminto/metabolismo , Larva/efeitos dos fármacos , Larva/genética , Larva/metabolismo , Masculino , Testes de Sensibilidade Parasitária , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Ovinos , Regulação para Cima , Zigoto/citologia , Zigoto/efeitos dos fármacos , Zigoto/metabolismo
10.
Heliyon ; 6(12): e05870, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33426348

RESUMO

Nutritional aspects modulate the parasitological and immune response in infected sheep. The aim of the present study was to evaluate the parasitological and humoral immune response of Pelibuey sheep experimentally infected with Haemonchus contortus that were fed diets with two different energy (n = 12) and protein (n = 12) levels. Twenty-four Pelibuey lambs infected with H. contortus were evaluated over 12 weeks. An additional six animals were considered as a control group. Fecal egg count (FEC) was determined, in addition to packed cell volume (PCV), total plasma protein (TPP), and immunoglobulin levels (IgA, IgG, and IgM) by indirect enzyme-linked immunosorbent assay (iELISA). Data were analyzed by repeated measures over time. The lambs that received a high-energy (HighE) diet had the lowest FEC (P < 0.01) regardless of whether they received a high (HighP) or low (LowP) level of protein. The effect of energy level was also observed over time: FEC values decreased and PCV and TPP values increased. Higher immunoglobulin levels were obtained for females (P < 0.05) than males yet, overall, the energy and protein levels of the diets did not affect the response of the immunoglobulins. Over time, however, an increase in IgG and IgM was observed, whereas the IgA level remained basal.

11.
Exp Parasitol ; 206: 107755, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31493393

RESUMO

The aim of the present study was to assess the expression of cytokines and FCεR1A receptor stimulated by Haemonchus placei larval excretory and secretory (ES) products associated with the pathogenesis in calves. Bovine peripheral blood mononuclear cells (PBMC) were stimulated in in vitro assays with H. placei L4 ES product at 8, 12, 16 and 24 h. ES products were collected in in vitro assays at 48 h with molecular weight of 72/60 kDa and isoelectric point of 7.2 pI. Specific IgG for infected and control calves, positive and negative, were employed to recognise H. placei larval ES products by indirect ELISA, showing a mean of 1.8, 0.83 and 0.28 OD, respectively, (p ≤ 0.001). The quantification of relative gene expression was performed using a set of cytokines (IL-2, IFNγ, TGFß, IL-4, IL-5, IL-6, IL-8, IL-10 and IL-13), FCεR1A receptor and housekeeping (GAPDH, ß-actin and ß-2-microglobulin) by RT-qPCR. An early increased expression, 2.2- to 3.4-fold change, of IL-2 (p ≤ 0.001), IL-5 and TGFß (p ≥ 0.05) was determined, followed by TGFß (30.7 and 14.14), IL-8 (102.8 and 1504.4) and IL-10 (60.4 and 1.7) (p ≤ 0.05) after 12 and 16 h, respectively, and reducing the expression level at 24 h. In addition, IL-6, IL-13 and FCεR1A receptor also displayed mild expression level, 2.1 - to 7.60-fold change, at 24 h (p ≥ 0.05). We conclude that ES products of 72/60 kDa collected in vitro from H. placei larvae are recognised by infected hosts and have the ability to induce diverse immune factors to modulate the nematode damage.


Assuntos
Citocinas/metabolismo , Haemonchus/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Receptores de IgE/metabolismo , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Citocinas/genética , Haemonchus/genética , Haemonchus/imunologia , Imunoglobulina G/metabolismo , Larva/genética , Larva/imunologia , Larva/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , RNA Mensageiro/metabolismo , Regulação para Cima
12.
Vet Parasitol Reg Stud Reports ; 17: 100292, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31303239

RESUMO

This is the first report about anthelmintic resistance (AR) in hair sheep farms determined in a sub-humid tropical climate, in an area known as Huasteca Potosina, Mexico. Faecal egg count reduction tests (FECRT) and egg hatch in vitro tests were conducted to identify the level of AR against benzimidazole (BZ) in parasitic gastrointestinal nematode (GIN) populations. An allele-specific polymerase chain reaction (AS-PCR) was performed to obtain a 250 bp band, indicating resistance, and a 550 bp band, indicating susceptibility to BZ. Macrocyclic lactones (ML) and imidazothiazole (IMZ) drugs were also tested with the FECRT. A PROBIT analysis was conducted using SAS to determine the 50% lethal doses (LD50) of the drugs according to the egg hatch in vitro test. Resistance to BZ and ML was found on all farms (0-70% effectiveness), whereas the susceptibility of nematodes to IMZ was detected with the FECRT (93-100% effectiveness). The LD50 was higher than the discriminating dose (0.1 µg ml-1) for BZ and confirmed AR to this anthelmintic; we also confirmed a high AR frequency with AS-PCR. Therefore, we suggest that strategic deworming should be performed to avoid the development of resistance to imidazothiazole.


Assuntos
Anti-Helmínticos/farmacologia , Lactonas/farmacologia , Infecções por Nematoides/veterinária , Nitroimidazóis/farmacologia , Doenças dos Ovinos/parasitologia , Tiazóis/farmacologia , Alelos , Animais , Anti-Helmínticos/uso terapêutico , Resistência a Medicamentos , Fezes/parasitologia , Feminino , Umidade , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/veterinária , Lactonas/uso terapêutico , Dose Letal Mediana , Masculino , México , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Nitroimidazóis/uso terapêutico , Contagem de Ovos de Parasitas , Reação em Cadeia da Polimerase/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Tiazóis/uso terapêutico , Clima Tropical
13.
Vet Parasitol ; 205(1-2): 246-54, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25060225

RESUMO

The aim of this study was to identify the presence of anthelmintic resistance to benzimidazole (BZ) in gastrointestinal nematodes (GIN) from naturally infected calves in the tropical regions of Campeche State of Mexico. The faecal egg count reduction test (FECRT) was conducted at 10 livestock farms localised in the Carmen, Candelaria, Champotón, Escárcega and Palizada municipalities of Campeche. The assessed anthelmintic was albendazole. The trial period was between August and November 2012. Infected calves were allocated into two groups, control and treated, on each farm. The number of eggs excreted per g of faeces was estimated by the McMaster technique at 0 and 14 days pre- and post- treatment, respectively. Recovered infective larvae (L3) (pre- and post-treatment) were identified using taxonomic keys and a genomic DNA (gDNA) template from a pool of L3 species prior to BZ treatment. Additionally, BZ-resistance polymorphisms in Haemonchus were determined by Allele Specific PCR (AS-PCR) at codon 200 and by end-point PCR at codons 200, 198 and 167 from isotype 1 of the ß-tubulin gene. Morphological identification revealed Haemonchus, Cooperia, Trichostrongylus, Ostertagia and Oesophagostumum L3 species before BZ treatment, and Haemonchus and Cooperia L3 species after treatment. Additionally, of the GIN populations, three exhibited BZ resistance, and seven were BZ-susceptible by FECRT. Molecular analysis identified mutations in Haemonchus populations on nine farms at codon 200 (TTC to TAC) by AS-PCR, while no changes were observed at 167 (TTC to TAC) or 198 (GAA to GCA) codons in any population. In conclusion, resistance to BZ was determined in Haemonchus and Cooperia nematodes in infected cattle in five tropical regions of Campeche State.


Assuntos
Anti-Helmínticos/farmacologia , Benzimidazóis/farmacologia , Doenças dos Bovinos/parasitologia , Haemonchus/genética , Nematoides/efeitos dos fármacos , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Resistência a Medicamentos/genética , Fezes/parasitologia , Feminino , México/epidemiologia , Nematoides/genética , Contagem de Ovos de Parasitas
14.
Vet. Méx ; 39(4): 423-428, oct.-dic. 2008. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-632893

RESUMO

The aim of this work was to determine the presence of ivermectin anthelmintic resistance in gastrointestinal parasitic nematodes in young cattle naturally infected in the state of Campeche, Mexico. This research was performed based on a survey of sanitary management to 35 cattlemen for the selection of suspicious herds with anthelmintic resistance problems. Calves from six to 12 months age were selected because no anthelmintic treatment had been given for at least 60 days and because they showed more than 200 eggs per gram of feces (epg) before treatment. Two groups of calves from seven to 13 each were randomly chosen; control group received no treatment, and treated group received ivermectin at a dose of 0.2 mg per kg of body weight, subcutaneously. Fourteen days after treatment, the epg number was determined and infective larvae genera were taxonomically identified. Data were analyzed using RESO program for anthelmintic resistance. The results indicated a concerning problem of ivermectin anthelmintic resistance in the evaluated cattle of five ranches with levels higher than 60%. The nematode genera identified before treatment were: Cooperia spp, Haemonchus spp and Oesophagostomum sp, and after treatment Cooperia spp still remained in five ranches, followed by Oesophagostomum sp and Haemonchus spp for two of the evaluated ranches. This research shows, for the first time in the state of Campeche, anthelmintic resistance in young cattle, as well as presence of gastrointestinal nematodes resistant to ivermectin.


El objetivo del presente trabajo fue detectar resistencia a ivermectina en nematodos gastrointestinales en bovinos jóvenes infectados naturalmente en Campeche, México. El trabajo se llevó a cabo con base en una encuesta de manejo sanitario realizada a 35 ganaderos para la selección de hatos sospechosos de problemas de resistencia antihelmíntica. Becerros de seis a 12 meses de edad fueron seleccionados debido a que no habían recibido tratamiento antihelmíntico en un periodo mínimo de 60 días y porque presentaron cuentas parasitarias mayores de 200 huevos por gramo de heces (hpg), antes del tratamiento. Se formaron dos grupos de bovinos al azar, de siete a 13 animales cada uno; el grupo testigo no recibió tratamiento, y grupo tratado recibió 0.2 mg por kg de peso de ivermectina, vía subcutánea. Catorce días después del tratamiento, se determinó el número de hpg y se identificaron los géneros de larvas infectantes. Los datos se analizaron en el programa RESO para resistencia antihelmíntica. Los resultados indicaron serios problemas de resistencia a ivermectina en el ganado vacuno evaluado en cinco ranchos con niveles mayores de 60%. Los nematodos identificados antes del tratamiento, Cooperia spp, Haemonchus spp y Oesophagostomum sp, y después del tratamiento fueron Cooperia spp en los cinco ranchos, seguido por Oesophagostomum sp y Haemonchus spp para dos de los ranchos evaluados. Este trabajo muestra evidencia, por primera vez en Campeche, de resistencia a ivermectina en bovinos jóvenes, así como presencia de tres géneros de nematodos gastrointestinales resistentes a ivermectina.

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