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1.
Zoolog Sci ; 37(1): 31-41, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32068372

RESUMO

Immune defense is costly to maintain and deploy, and the optimal investment into immune defense depends on risk of infection. Altitude is a natural environmental factor that is predicted to affect parasite abundance, with lower parasite abundance predicted at higher altitudes due to stronger environmental stressors, which reduce parasite transmission. Using high and low altitude populations of the Turkish blind mole-rat (TBMR) Nannospalax xanthodon, we tested for effects of altitude on constitutive innate immune defense. Field studies were performed with 32 wild animals in 2017 and 2018 from two low- and one high-altitude localities in the Central Taurus Mountains, at respective altitudes of 1010 m, 1115 m, and 2900 m above sea level. We first compared innate standing immune defense as measured by the bacteria-killing ability of blood serum. We then measured corticosterone stress hormone levels, as stressful conditions may affect immune response. Finally, we compared prevalence and intensity of gastrointestinal parasites of field-captured TBMR. We found that the bacteria-killing ability of serum is greater in the mole-rat samples from high altitude. There was no significant difference in stress (corticosterone) levels between altitude categories. Coccidian prevalence and abundance were significantly higher in 2017 than 2018 samples, but there was no significant difference in prevalence, abundance, or intensity between altitudes, or between sexes. Small sample sizes may have reduced power to detect true differences; nevertheless, this study provides support that greater standing innate immunity in high altitude animals may reflect greater investment into constitutive defense.


Assuntos
Altitude , Imunidade Inata , Ratos-Toupeira/imunologia , Animais , Coccídios/isolamento & purificação , Corticosterona/sangue , Feminino , Trato Gastrointestinal/parasitologia , Masculino , Nematoides/isolamento & purificação , Contagem de Ovos de Parasitas/métodos , Contagem de Ovos de Parasitas/veterinária , Teste Bactericida do Soro/métodos , Teste Bactericida do Soro/veterinária
2.
Vet Parasitol ; 276: 108973, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31785456

RESUMO

The objective of this study was to measure the effect of the nutritional status of Creole goat kids on the host responses and the nematode population established after an experimental H. contortus infection. Fifty six kids were fed with 4 diets corresponding to 2 nutritional statuses: the low nutritional status (HAY, hay ad libitum and HB, Hay ad libitum + banana) and the high nutritional status (HS, hay ad libitum + soya meal and HSB, hay ad libitum + banana + soya meal). For each diet, 8 kids were experimentally infected with 10,000 H. contortus infective larvae (L3) and 6 kids were kept as non-infected controls. From the day of infection until 6 weeks post-infection, samples were collected to measure individual intake, total tract digestibility, parasitological and hematological parameters. The dry matter intake (DMI), the average daily gain (ADG), the crude protein (CP) and the digestible CP intake were higher in goats fed the HS and HSB diets, but no statistically significant interaction between the nutritional status and the infection was observed. The packed cell volume (PCV), the red blood cell counts (RBC) and the mean corpuscular volume (MCV) were higher with the HS and the HSB diets. In kids with the high nutritional status the nematode burden and pathophysiological impact of the infection were significantly lower but not the FEC. In conclusion, this reduced establishment rate was associated with an increased production of eggs by the female parasites and suggested a phenomenon of density-dependent prolificacy of H. contortus probably inherent to the fitness of the parasite population.


Assuntos
Doenças das Cabras/parasitologia , Hemoncose/veterinária , Haemonchus/crescimento & desenvolvimento , Estado Nutricional/fisiologia , Anemia/prevenção & controle , Anemia/veterinária , Ração Animal/análise , Ração Animal/normas , Animais , Dieta/veterinária , Digestão , Ingestão de Alimentos , Eosinófilos/citologia , Fezes/química , Fezes/parasitologia , Feminino , Doenças das Cabras/fisiopatologia , Doenças das Cabras/prevenção & controle , Cabras , Hemoncose/parasitologia , Hemoncose/fisiopatologia , Contagem de Leucócitos/veterinária , Masculino , Contagem de Ovos de Parasitas/veterinária , Pepsinogênio A/sangue
3.
Exp Parasitol ; 207: 107777, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31626795

RESUMO

Gastrointestinal nematodes are a main problem for ruminant production, reducing animal performance and increasing environmental impact per unit of animal product generated. Tannin supplementation may lead to positive results regarding aspects such as parasitic infections and methane (CH4) emissions. Therefore, the objective of this experiment was to evaluate the effects of the condensed tannins (CT) extract made of powdered Acacia mearnsii bark (PAB) on nutrition, parasitic status and CH4 emissions in sheep artificially infected with Trichostrongylus colubriformis and Haemonchus contortus. Twenty 10-month old Santa Inês lambs (24.7 ± 3.14 kg of initial body weight) were used in a 50-day trial. Animals were divided in four treatment groups according to parasitic infection and PAB supplementation: two control groups without infections, one without PAB (C-) (n = 4) and one with PAB (C+) (n = 4); two infected groups, one without PAB (I-) (n = 6) and another receiving PAB (I+) (n = 6). Initially, animals were kept in individual pens where they were fed ad libitum chopped tifton 85 hay (Cynodon spp.) and 210 g/animal/day of concentrate. On the first day of experiment, animals of I- and I+ groups were artificially infected with infective larvae (L3) of T. colubriformis and H. contortus. Lambs were weighed fortnightly to calculate average daily body weight gain (ADG). Blood and faeces samples were also collected in the same moment of weighing for the evaluation of blood parameters and faecal egg count (FEC) respectively. After 40 days of experiment, measurements of CH4 emissions in small chamber system started and following that, apparent total tract digestibility (ATTD) assay was carried out in metabolic cages. In the end of experimental period (50 days), lambs were slaughtered and samples of abomasum and small intestine content were collected for worm count, identification, and eggs/female count. No significant (p > 0.05) treatment effects were verified for ADG, ATTD and worm count. Blood parameters were affected in both infected groups (p < 0.05) from the 28th experimental day onwards, when these animals started to show reduced red blood cells, haemoglobin and packed cell volume when compared to C- and C+. Decreased FEC was verified in I+ when compared to I- and also, H. contortus eggs/female worm for I+ was lower than for I- (p < 0.05). Both infected groups showed higher CH4 emissions than the control groups (p < 0.05). Results highlighted the anthelmintic potential of PAB and indicated methanogenic effect of parasitic nematode infections.


Assuntos
Acacia , Hemoncose/veterinária , Extratos Vegetais/administração & dosagem , Doenças dos Ovinos/dietoterapia , Taninos/administração & dosagem , Tricostrongilose/veterinária , Animais , Suplementos Nutricionais , Contagem de Eritrócitos/veterinária , Fezes/parasitologia , Feminino , Hemoncose/dietoterapia , Hemoncose/parasitologia , Haemonchus/classificação , Hematócrito/veterinária , Hemoglobinas/análise , Masculino , Metano/metabolismo , Contagem de Ovos de Parasitas/veterinária , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/parasitologia , Tricostrongilose/dietoterapia , Tricostrongilose/parasitologia , Trichostrongylus/classificação , Ganho de Peso
4.
BMC Vet Res ; 15(1): 333, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533718

RESUMO

BACKGROUND: Haemonchosis is one of the most economically important parasitic diseases affecting small ruminants all over the world. Chemotherapeutic control has several shortcomings (limited anthelmintic arsenal, frequent resistance) and is hardly affordable by many farm economies. A recombinant antigen (rHc23) was shown to induce significant protection in vaccination trials with single dose challenges and different adjuvants. RESULTS: Lambs were vaccinated with 100 µg rHc23/dose + bacterial immunostimulant (BI) (LPS from Escherichia coli + Propionibacterium acnes extract) (days - 2, 0, 7 and 14) and subjected to a trickle infection with two dosages [6x, 1000 infective larvae (L3) or 6x, 2000 L3]. Vaccinated lambs showed a significant antibody response against rHc23 and Haemonchus contortus soluble extract as assessed by ELISA and Western blot (WB). Fecal egg counts (epg) along the experiment of vaccinated and BI treated lambs were significantly reduced. All vaccinated animals showed total egg output and abomasal helminth burdens (median, average) lower than those from unvaccinated or BI-treated animals lambs although differences were not statistically significant. CONCLUSIONS: Vaccination with 100 µg rHc23/dose + BI against H.contortus trickle infections apparently induced lower epg values and helminth burdens at the end of the experiment. Intragroup individual variations did not allow to obtain conclusive results and more research is needed including adjuvants and larger groups of animals to validate the potential value of rHc23 as candidate to develop a recombinant vaccine for lambs haemonchosis.


Assuntos
Antígenos de Helmintos/imunologia , Hemoncose/veterinária , Doenças dos Ovinos/parasitologia , Abomaso/parasitologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Feminino , Hemoncose/imunologia , Hemoncose/prevenção & controle , Haemonchus/imunologia , Contagem de Ovos de Parasitas/veterinária , Proteínas Recombinantes/imunologia , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/prevenção & controle , Carneiro Doméstico , Vacinação/veterinária
5.
Vet Parasitol ; 274: 108922, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31539665

RESUMO

Fasciolosis among domestic ruminants has resulted in a decrease in the production of milk products and has occasionally led to the deaths of young ruminants due to of acute infections. This study aimed to discriminate between the eggs of Fasciola gigantica and other trematode eggs in samples collected from ruminant feces specimens using PCR-based methods with the new candidate gene Cytochrome B (CYTB). A species-specific primer was developed with a high degree of sensitivity (3.285 pg). The primer was able to amplify the F. gigantica genomic DNA and there were no positive results with the other related trematodes (Paramphistomum sp., Orthocoelium sp., Fischoederius sp., Calicophoron sp., Echinostoma revolutum, E. cinetorchis, E. ilocanum and Isthmiophora hortensis), freshwater snails (Lymnaea auricularia, Bithynia siamensis, Indoplanorbis exustus, Melanoides tuberculata, Tarebia granifera) or definitive hosts (Bos primigenius and Bubalus bubalis). The minimum concentration of DNA from eggs that could be give a positive result was 3.285 pg. Moreover, the results of the study confirmed the existence of F. gigantica in Nakhon Pathom Province with a high prevalence (28.57%) and revealed the area of infection through epidemiological mapping. Thus, the species-specific primer and epidemiological data in this study may be helpful for use in epidemiological studies, phylogenetic studies and veterinary studies in the future.


Assuntos
Doenças dos Bovinos/parasitologia , Citocromos b/isolamento & purificação , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Fezes/parasitologia , Sequência de Aminoácidos , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Fasciola/enzimologia , Fasciola/genética , Fasciolíase/diagnóstico , Fasciolíase/parasitologia , Óvulo , Contagem de Ovos de Parasitas/veterinária , Filogenia , Prevalência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie , Tailândia/epidemiologia
6.
J Anim Sci ; 97(11): 4428-4444, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31541548

RESUMO

The aim of this study was to identify for the first time single nucleotide polymorphisms (SNPs) associated with Haemonchus contortus resistance in Florida Native sheep, using a targeted sequencing approach. One hundred and fifty-three lambs were evaluated in this study. At the start of the trial, phenotypic records for fecal egg count (FEC), FAMACHA score, body condition score (BCS), and weight were recorded and deworming of sheep with levamisole (18 mg/kg of body weight) was performed. Ten days post-deworming (baseline) and 28 d post-baseline, a full hematogram of each sheep was obtained and FEC, FAMACHA score, BCS, and weight were assessed. Average daily gain was calculated at the end of the trial. Out of 153 animals, 100 sheep were selected for genotyping using a targeted sequencing approach. Targeted sequencing panel included 100 candidate genes for immune response against H. contortus. SNPs were discarded if call rate <95% and minor allele frequency ≤0.05. A mixed model was used to analyze the response variables and included the identity by state matrix to control for population structure. A contemporary group (age, group, and sex) was included as fixed effect. Bonferroni correction was used to control for multiple testing. Eighteen SNPs on chromosomes 1, 2, 3, 4, 6, 7, 11, 15, 18, 20, 24, and 26 were significant for different traits. Our results suggest that loci related to Th17, Treg, and Th2 responses play an important role in the expression of resistant phenotypes. Several genes including ITGA4, MUC15, TLR3, PCDH7, CFI, CXCL10, TNF, CCL26, STAT3, GPX2, IL2RB, and STAT6 were identified as potential markers for resistance to natural H. contortus exposure. This is the first study that evaluates potential genetic markers for H. contortus resistance in Florida Native sheep.


Assuntos
Resistência à Doença/genética , Estudo de Associação Genômica Ampla/veterinária , Hemoncose/veterinária , Haemonchus/imunologia , Doenças dos Ovinos/imunologia , Animais , Peso Corporal , Fezes/parasitologia , Feminino , Florida , Técnicas de Genotipagem/veterinária , Hemoncose/imunologia , Hemoncose/parasitologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Fenótipo , Ovinos , Doenças dos Ovinos/parasitologia , Linfócitos T Reguladores/imunologia
7.
Vet Parasitol ; 272: 40-43, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31395203

RESUMO

In this study we evaluated the efficacy of trichlorfon against Haemonchus contortus, monitoring its influence on blood parameters and plasma enzymes of lambs with haemonchosis. A lamb group was orally treated with trichlorfon at 100 mg kg-1 while the other group was untreated. Split-plot design analysis was performed with the lamb groups defined as plots while the subplots were the four periods (weeks) of collection. The trichlorfon treatment promoted a significant and effective reduction of fecal egg counts after one week, with efficacies > 99%. After 21 days of treatment, detected blood parameters and serum levels of plasma enzymes were normal. Additionally, serum albumin and urea concentrations increased to normal values, which were not observed in untreated lambs. The treatment with this organophosphate, using a correct oral administration, may represent an effective therapeutic alternative for sheep infected with multi resistant strain of H. contortus.


Assuntos
Hemoncose/veterinária , Doenças dos Ovinos/tratamento farmacológico , Triclorfon/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Proteínas Sanguíneas/análise , Enzimas/sangue , Hemoncose/sangue , Haemonchus , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/sangue
8.
Vet Parasitol ; 272: 53-57, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31395205

RESUMO

The detection and quantification of nematode eggs using fecal egg count techniques have an irreplaceable role in equine parasitic control. The reliability, particularly precision and accuracy, of individual techniques have been described only for strongylid infections. The aim of this study was to compare three fecal egg count techniques used for the detection of the two most common equine nematode infections: strongylid and ascarid. The Simple McMaster, Concentration McMaster and Mini-FLOTAC techniques were tested on spiked fecal samples with various levels of egg concentration (50, 100, 200, 500, 1000 and 3000 eggs per gram) and naturally infected mixed strongylid-ascarid samples with 30 replicates. The Simple McMaster, Concentration McMaster and Mini-FLOTAC techniques had precision coefficients of variation of 44.33, 35.64 and 18.25% for the strongylid infection and 62.95, 35.71 and 18.95% for the ascarid infection, and percent accuracies (mean count/number of eggs spiked) of 97.53, 88.39 and 74.18% for the strongylid infection and 65.53, 83.18 and 90.28% for the ascarid infection, respectively. Accuracy depended greatly on the type of nematode, but precision did not. The Mini-FLOTAC technique was more precise than the Simple and Concentration McMaster techniques regardless of nematode type. Simple McMaster was the most accurate technique for detecting strongylid eggs, and Mini-FLOTAC was the most accurate technique for detecting ascarid eggs. Our results indicated that none of the current techniques were universally and sufficiently reliable for the simultaneous quantification of both of these common equine nematodes.


Assuntos
Ascaridíase/veterinária , Fezes/parasitologia , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/parasitologia , Contagem de Ovos de Parasitas/veterinária , Infecções Equinas por Strongyloidea/diagnóstico , Infecções Equinas por Strongyloidea/parasitologia , Animais , Ascaridíase/diagnóstico , Ascaridíase/parasitologia , Cavalos , Contagem de Ovos de Parasitas/normas , Reprodutibilidade dos Testes
9.
Parasitol Res ; 118(10): 2901-2907, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388787

RESUMO

Cooperia sp. and Ostertagia sp. are two cosmopolitan parasitic nematodes often found in mixed gastrointestinal infections in cattle across temperate regions. In light of the recent increase in the emergence of anthelmintic resistance in these and other nematodes derived from cattle around the globe, and their negative impact on animal health and productivity, novel molecular assays need to be put forth in order to facilitate the monitoring of parasite burden in infected herds, using pasture and/or fecal samples. Here, we describe a novel droplet digital PCR platform-based concept for precise identification and quantification of the two most abundant and important parasite genera in grazing western European cattle. By exploiting a single nucleotide difference in the two parasites' ITS2 sequence regions, we have developed two specific hydrolysis probes labeled with FAM™ or HEX™ fluorophores, which can not only distinguish between the DNA sequences of the two, but also quantify them in mixed DNA samples. A third, newly developed universal probe was also tested along the genus-specific probes to provide a robust and accurate reference. It was evident that the universal probe displayed congruent results to those obtained by the genus-specific probes when used with DNA from both parasites in a single sample. All in all, the results of our assay suggest that this novel protocol could be used to distinguish and quantify cattle parasites belonging to the two most important genera (i.e., Cooperia and Ostertagia) in a single mixed DNA sample.


Assuntos
Doenças dos Bovinos/diagnóstico , DNA de Helmintos/genética , Enteropatias Parasitárias/veterinária , Ostertagia/genética , Trichostrongyloidea/genética , Animais , Anti-Helmínticos/uso terapêutico , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Fezes/parasitologia , Gastroenteropatias , Enteropatias Parasitárias/diagnóstico , Enteropatias Parasitárias/tratamento farmacológico , Contagem de Ovos de Parasitas/veterinária , Reação em Cadeia da Polimerase/métodos
10.
Exp Parasitol ; 205: 107735, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31381870

RESUMO

Two experiments were performed to determine whether oral administration of copper oxide capsules controlled helminthic infections in Lacaune sheep without acute collateral effects on animal health. In experiment 1, 48 multiparous lactating sheep (60.1 ±â€¯8.5 kg) were stratified according to initial number of eggs (Haemonchus contortus) per gram of feces (EPG) and were assigned randomly to 1 of two treatments (24 sheep/treatment): no oral administration (control) or oral administration of two copper capsules (treated; approximately 58 mg copper/kg body weight). Blood and fecal samples were collected on days 0, 15 and 45. Animals treated with copper capsules showed lower of EPG, eosinophils, acetylcholinesterase (AChE) in whole blood, and lower butyrylcholinesterase (BChE) activity in serum. Treated sheep had higher erythrocyte numbers, hemoglobin concentrations, hematocrit, and lymphocyte numbers. In experiment 2, 12 male lambs negative for helminths and coccidia were assigned randomly to one of two treatments (six lambs/treatment): control or treated (one copper capsule; approximately 58 mg copper/kg body weight); the experiment was designed to determine whether the results of experiment 1 were due to treatment or parasitism. Blood samples were collected on days 0, 5, 10 and 15 and fecal samples were collected on days 0, 7 and 15. Treated animals showed greater concentrations of lymphocytes; however, treatment had no effect on other hemogram variables, AChE and BChE activities, or levels of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, creatinine, urea, albumin, total protein, and reactive oxygen species. These data suggest that copper capsules in dairy sheep efficiently controlled H. contortus infections. Treatment was not harmful to lambs during the first 15 days, i.e. there were no signs of acute toxicity.


Assuntos
Cobre/administração & dosagem , Hemoncose/veterinária , Helmintíase Animal/tratamento farmacológico , Lactação , Doenças dos Ovinos/tratamento farmacológico , Acetilcolinesterase/sangue , Administração Oral , Animais , Butirilcolinesterase/sangue , Cápsulas , Cobre/uso terapêutico , Indústria de Laticínios , Resíduos de Drogas , Eosinófilos/efeitos dos fármacos , Contagem de Eritrócitos/veterinária , Fezes/parasitologia , Feminino , Hemoncose/tratamento farmacológico , Hemoncose/prevenção & controle , Helmintíase Animal/sangue , Helmintíase Animal/prevenção & controle , Hematócrito/veterinária , Hemoglobinas/análise , Contagem de Linfócitos/veterinária , Masculino , Leite/química , Contagem de Ovos de Parasitas/veterinária , Paridade , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/prevenção & controle
11.
Prev Vet Med ; 170: 104736, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31421502

RESUMO

Dicrocoeliasisis caused by the small liver fluke (Dicrocoelium spp.), mainly Dicrocoelium dendriticum in domestic and wild ruminants. The small liver fluke is the probable predisposing cause of economic burden. The impact of geographic and climatic factors on the incidence of dicrocoeliasis has been severely ignored in different geographical areas. Due to the lack of data regarding dicrocoeliasis in Iran, this study was aimed to investigate the prevalence and intensity of ovine and bovine Dicrocoelium infection in the coastal strip south of the Caspian Sea. Fecal samples were obtained from the cattle and sheep in three provinces of Guilan, Mazandaran and Golestan at the littoral of the Caspian Sea. All collected samples were then tested by flotation methods for determining the number of eggs per gram of feces (EPG). Moreover, we applied maximum entropy niche-based modeling (MaxEnt), coupled with remote sensing and the Geographical Information System (GIS) to visualize the spatial distribution and risk factors of Dicrocoelium dendriticum at the littoral of Caspian Sea. A total of 2688 stool samples were collected from cattle (n = 1344) and sheep (n = 1344) in coastal provinces of the Caspian Sea including Guilan (n = 1280), Mazandaran (n = 768) and Golestan (n = 640) provinces. Based on the data presented here, the highest rate of infection was observed in Guilan and Mazandaran provinces. The results revealed the prevalence rates of 36.72% and 6.09% for sheep and cattle in Guilan province, respectively. This rate was 22.4% for sheep and 3.91% for cattle in Mazandaran province. However, the rate of sheep infection was 90% in some point locations. Dicrocoelium infection was found to be significantly different between three provinces in sheep (P < 0.00001, Chi = 111.633). Our findings exhibited a high reliability of the MaxEnt model, and area under the curve (AUC) values of the training and test data sets were determined to be 0.852 and 0.818, respectively. Jackknife analysis showed the relative variable contribution to the model performance, where four variables were found as key influential factors that highly affected the habitat suitability of the presence of the lancet fluke including the precipitation of driest quarter (Bio17), altitude, temperature seasonality (Bio4), and precipitation of driest month (Bio14). The findings of this study demonstrated a high presence rate of Dicrocoelium infection at the littoral of Caspian Sea, Iran. Moreover, climatic variables can be considered as important predictive factors affecting the distribution of infection in the studied areas. Further studies based on the findings of the GIS are also very important in the country for planning control programs.


Assuntos
Distribuição Animal , Doenças dos Bovinos/epidemiologia , Dicrocelíase/veterinária , Dicrocoelium/fisiologia , Ecossistema , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Dicrocelíase/epidemiologia , Dicrocelíase/parasitologia , Fezes/parasitologia , Irã (Geográfico)/epidemiologia , Conceitos Meteorológicos , Modelos Biológicos , Contagem de Ovos de Parasitas/veterinária , Prevalência , Ovinos , Doenças dos Ovinos/parasitologia
12.
J Vet Intern Med ; 33(5): 2336-2342, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31454105

RESUMO

BACKGROUND: Mycoplasma haemolamae (Mhl) and gastrointestinal nematodes can cause anemia in camelids. Control programs aim to suppress parasitism without promoting anthelminthic resistance, but few evidence-based guidelines define acceptable parasite loads in camelids. HYPOTHESIS/OBJECTIVES: In clinically healthy nonanemic camelids, compare erythrocyte variables to Mhl real-time PCR status and to fecal egg count (FEC). Determine the FEC threshold above which erythrocyte variables are consistently below reference interval medians. ANIMALS: One hundred fourteen client-owned adult alpacas and llamas. METHODS: In a cross-sectional study, whole blood in ethylenediaminetetraacetic acid (EDTA) was assessed for packed cell volume (PCV) by centrifugation, erythrocyte count (RBC), and hemoglobin concentration (HGB) using an ADVIA120 analyzer, and Mhl using real-time PCR. Trichostrongyle eggs per gram (epg) were counted by modified McMaster test on freshly collected feces. Significant differences in erythrocyte variables based on Mhl status and FEC thresholds were assessed by independent t test and one-way ANOVA, respectively. RESULTS: Packed cell volume, RBC, and HGB were not significantly different between Mhl-positive and Mhl-negative animals, but were significantly lower in animals with FEC >1000 epg compared to those with <500 epg. All animals with FEC >600 epg had RBC and HGB below the reference interval median. All animals with FEC >750 epg had PCV below the reference interval median. CONCLUSIONS AND CLINICAL IMPORTANCE: In healthy nonanemic camelids, positive Mhl PCR is not associated with lower erythrocyte variables and such animals may not warrant treatment. Fecal egg count >600-750 epg has a negative effect on erythrocyte variables, and may be a guide for deworming protocols.


Assuntos
Camelídeos Americanos/microbiologia , Camelídeos Americanos/parasitologia , Infecções por Mycoplasma/veterinária , Tricostrongiloidíase/veterinária , Animais , Camelídeos Americanos/sangue , Estudos Transversais , Contagem de Eritrócitos/veterinária , Feminino , Hematócrito/veterinária , Hemoglobinas/análise , Masculino , Mycoplasma/isolamento & purificação , Infecções por Mycoplasma/sangue , Infecções por Mycoplasma/epidemiologia , Contagem de Ovos de Parasitas/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Tennessee/epidemiologia , Trichostrongyloidea/isolamento & purificação
13.
Parasitol Res ; 118(10): 2877-2883, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422463

RESUMO

Anthelmintic resistance in equine cyathostomin parasites is widespread. A surveillance-based parasite control program using fecal egg counts (FECs) and fecal egg count reduction tests (FECRTs) to decrease anthelmintic use and monitor treatment efficacy is recommended. The purpose of this study was to examine shifts in equine parasite control program management practices via a short course presented by the Penn State Extension, and to highlight how data collected from these programs is useful for monitoring anthelmintic efficacy on a large scale. Horse owners were enrolled after participating in a short course and filled out questionnaire surveys about their parasite management programs pre and post study, horse information, and farm information. FECs were performed at three time points, and horses above a 300 strongyle eggs per gram cut-off were treated with pyrantel pamoate, fenbendazole, or ivermectin. Two weeks post-treatment, FECRTs were performed to determine treatment efficacy, which included 29 farms with 513 individual treatments. Prior to the study, only 30.6% of farms used FECs, but after the study, 97.3% of farms said they would use FECs in the future. Horses were given an average of 4.1 anthelmintic treatments per year before the study, and post study 89.2% of farms were able to reduce the number of anthelmintic treatments used. Fenbendazole was effective on zero farms, pyrantel pamoate on 7.4% of farms, and ivermectin on 92.9% of farms. This outreach project helped generate information about anthelmintic efficacy levels, causing a shift in practices on participating farms, and collected useful anthelmintic resistance data.


Assuntos
Antinematódeos/uso terapêutico , Fenbendazol/uso terapêutico , Doenças dos Cavalos/epidemiologia , Ivermectina/uso terapêutico , Contagem de Ovos de Parasitas/veterinária , Pamoato de Pirantel/uso terapêutico , Animais , Resistência a Medicamentos/efeitos dos fármacos , Fazendas , Fezes/parasitologia , Doenças dos Cavalos/tratamento farmacológico , Doenças dos Cavalos/parasitologia , Cavalos , Inquéritos e Questionários
14.
Exp Parasitol ; 204: 107726, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31299264

RESUMO

The aims of this study were to evaluate if the use of copper oxide wire particles, isolated or in association with closantel, in lambs infected with Haemonchus contortus enhances the anthelmintic efficacy of closantel, as well as to evaluate the effects of treatment in hepatic energy metabolism, inflammatory markers and hematological and biochemical tests. The lambs were randomly divided into five groups (6 animals each), as follows: uninfected animals (Control); animals infected with H. contortus (HC); infected and treated with closantel (HC + CL); infected and treated with copper oxide wire particles (HC + Cu); and infected and treated with closantel plus copper oxide wire particles (HC + CL + Cu). The animals of infected groups were infected orally with H. contortus (5,000 L3 -larvae) and on day 14 post infection (p.i) the treatments were initiated. The egg per gram of feces (EPG), butyrylcholinesterase (BuChE), myeloperoxidase (MPO), adenylate kinase (AK) and pyruvate kinase (PK) activities and hematological and biochemical tests were evaluated. Treatments with copper oxide (isolated and associated) were able to reduce the EPG count on days 28, 35, 42 and 49 p.i when compared to HC group, while closantel was able to reduce EPG only from day 35 p.i. Moreover, treatment with closantel (isolated or associated) was able to prevent the inhibition of hepatic AK and PK activities caused by H. contortus infection, which may contribute to efficient intracellular energetic communication in order to maintain the balance between cellular ATP consumption and production. Butyrylcholinesterase and MPO activities were higher in infected lambs compared to uninfected, while treated groups showed lower enzymatic activity compared to the group HC. The use of all therapeutic protocols was able to reduce the EPG count. Based on these evidences, the use of copper oxide plus closantel may be considered an alternative to treat lambs infected by H. contortus.


Assuntos
Anti-Helmínticos/administração & dosagem , Cobre/administração & dosagem , Hemoncose/veterinária , Inflamação/veterinária , Salicilanilidas/administração & dosagem , Doenças dos Ovinos/tratamento farmacológico , Abomaso/metabolismo , Adenilato Quinase/metabolismo , Administração Oral , Animais , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Análise Química do Sangue/veterinária , Butirilcolinesterase/sangue , Cápsulas , Metabolismo Energético/efeitos dos fármacos , Contagem de Eritrócitos/veterinária , Fezes/parasitologia , Hemoncose/complicações , Hemoncose/tratamento farmacológico , Hemoncose/metabolismo , Hematócrito/veterinária , Hemoglobinas/análise , Inflamação/tratamento farmacológico , Inflamação/prevenção & controle , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Contagem de Ovos de Parasitas/veterinária , Peroxidase/sangue , Piruvato Quinase/metabolismo , Distribuição Aleatória , Salicilanilidas/farmacologia , Salicilanilidas/uso terapêutico , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/prevenção & controle
15.
Parasit Vectors ; 12(1): 330, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266521

RESUMO

BACKGROUND: Endoparasites are considered a major health problem of South American camelids as shown in a recent survey among German and Austrian camelid owners. Although prophylactic and therapeutic measures such as application of anthelmintics are commonly used, treatment efficacy is usually not assessed. Owners have expressed significant concerns regarding the effect of antiparasitic therapy, so this study aimed to evaluate the outcome of anthelmintic treatment in German alpaca herds with different drugs. RESULTS: Overall, 617 samples from 538 clinically healthy alpacas > 1 year-old from 27 farms (n = 11-157 animals/herd) were examined. The most common parasites detected by flotation were Eimeria spp. (75.1%) followed by strongylids (55.0%), Nematodirus spp. (19.3%), cestodes (3.1%) and Trichuris (2.7%). After initial coproscopical examination by flotation and strongylid egg quantification by the McMaster technique, positive animals excreting at least 150 eggs per gram of faeces were included in a faecal egg count reduction test (FECRT) using fenbendazole (n = 71 samples), moxidectin (n = 71) or monepantel (n = 66). Pre-treatment larval cultures (n = 23 positive pooled farm samples) revealed Haemonchus (87% of the farms), Cooperia (43.5%), Trichostrongylus (21.7%), Ostertagia (13.0%), Nematodirus and Oesophagostomum (4.3% each). Fenbendazole treatment reduced egg excretion by 45%, moxidectin by 91% and monepantel by 96%. On the farm level, 13/18 farms that used fenbendazole, 6/6 farms that used moxidectin and 2/5 farms that used monepantel had individual FECR values < 90% (fenbendazole) or < 95% (moxidectin, monepantel). Haemonchus and Cooperia were overrepresented on the farms with reduced treatment efficacy. CONCLUSIONS: Gastrointestinal strongylids are common in German alpacas and fenbendazole in particular was not sufficiently effective to reduce strongylid egg excretion. Although the FECRT could not unambiguously determine anthelmintic resistance in the present study, the finding that small ruminant strongylids, especially Haemonchus, are common in alpacas indicates that determination of effective anthelmintic doses, monitoring of efficacy and adapted (selective) treatment regimens must be implemented as part of sustainable deworming practices in this species in accordance with recommendations for ruminants.


Assuntos
Anti-Helmínticos/administração & dosagem , Camelídeos Americanos/parasitologia , Helmintíase Animal/prevenção & controle , Enteropatias Parasitárias/veterinária , Infecções por Strongylida/veterinária , Estrongilídios/efeitos dos fármacos , Aminoacetonitrila/administração & dosagem , Aminoacetonitrila/análogos & derivados , Animais , Fezes/parasitologia , Feminino , Fenbendazol/administração & dosagem , Haemonchus/efeitos dos fármacos , Helmintíase Animal/parasitologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/prevenção & controle , Macrolídeos/administração & dosagem , Masculino , Contagem de Ovos de Parasitas/veterinária , Infecções por Strongylida/parasitologia , Infecções por Strongylida/prevenção & controle
16.
J Dairy Sci ; 102(9): 8251-8263, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31326168

RESUMO

Information is scarce regarding the epidemiology of gastrointestinal nematodes in Canadian dairy heifers. The objectives of this study were to estimate the prevalence and fecal egg counts of gastrointestinal nematodes in dairy heifers, and using a novel deep-amplicon sequencing approach, to identify the predominant gastrointestinal nematode species in Canadian dairy replacement heifers. Fresh environmental fecal samples (n = 2,369) were collected from replacement heifers on 306 dairy farms across western Canada, Ontario, Québec, and Atlantic Canada. Eggs per gram of feces (EPG) were determined using a modified Wisconsin double-centrifugation sugar flotation technique. Predominant nematode species at the farm level were identified by deep-amplicon nemabiome sequencing of the internal transcribed spacer-2 rDNA locus of nematode third-stage larvae. Generalized estimating equations were used to estimate predicted parasite prevalence and mean EPG in all heifers and by province, allowing for clustering within herds. Individual heifer egg counts ranged from 0 to 141 EPG (median: 0 EPG; interquartile range: 0 to 71 EPG). Gastrointestinal nematodes were detected in 20.9% (95% confidence interval: 17.2 to 24.6%) of heifers, and the predicted mean strongylid EPG accounting for clustering on farms was 1.1 (95% confidence interval: 0.6 to 1.6). The predominant parasite species were Cooperia oncophora and Ostertagia ostertagi. This is the first study in Canada to use a combination of deep-amplicon nemabiome sequencing and a traditional egg count method to describe the epidemiology of gastrointestinal nematodes in dairy heifers.


Assuntos
Doenças dos Bovinos/epidemiologia , Fezes/parasitologia , Trato Gastrointestinal/parasitologia , Nematoides/classificação , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas/veterinária , Animais , Canadá/epidemiologia , Bovinos , Feminino , Infecções por Nematoides/epidemiologia , Prevalência
17.
PLoS One ; 14(6): e0218719, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31220166

RESUMO

Gastrointestinal nematodes (GIN) are a major constraint for small ruminant production. Due to the rise of anthelmintic resistance throughout the world, alternative control strategies are needed. The development of GIN resistance breeding programs is a promising strategy. However, a better understanding of the mechanisms underlying genetic resistance might lead to more effective breeding programmes. In this study, we compare transcriptome profiling of abomasal mucosa and lymph node tissues from non-infected, resistant and susceptible infected Creole goats using RNA-sequencing. A total of 24 kids, 12 susceptible and 12 GIN resistant based on the estimated breeding value, were infected twice with 10,000 L3 Haemonchus contortus. Physiological and parasitological parameters were monitored during infection. Seven weeks after the second infection, extreme kids (n = 6 resistant and 6 susceptible), chosen on the basis of the fecal egg counts (FEC), and 3 uninfected control animals were slaughtered. Susceptible kids had significantly higher FEC compared with resistant kids during the second infection with no differences in worm burden, male and female worm count or establishment rate. A higher number of differentially expressed genes (DEG) were identified in infected compared with non-infected animals in both abomasal mucosa (792 DEG) and lymph nodes (1726 DEG). There were fewer DEG in resistant versus susceptible groups (342 and 450 DEG, in abomasal mucosa and lymph nodes respectively). 'Cell cycle' and 'cell death and survival' were the main identified networks in mucosal tissue when comparing infected versus non-infected kids. Antigen processing and presentation of peptide antigen via major histocompatibility complex class I were in the top biological functions for the DEG identified in lymph nodes. The TGFß1 gene was one of the top 5 upstream DEG in mucosal tissue. Our results are one of the fist investigating differences in the expression profile induced by GIN infection in goats.


Assuntos
Gastroenteropatias/genética , Doenças das Cabras/genética , Cabras , Infecções por Nematoides/genética , Transcriptoma , Animais , Suscetibilidade a Doenças/parasitologia , Feminino , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/parasitologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Predisposição Genética para Doença , Doenças das Cabras/parasitologia , Cabras/genética , Cabras/parasitologia , Masculino , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas/veterinária
18.
Vet Parasitol ; 270: 7-12, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213242

RESUMO

This study investigated the impact of variability in Parascaris spp. and strongyle faecal egg counts (FEC) from foals on treatment decision-making and detection of a patent infection. A single faecal sample was collected once daily for three days from 53 foals and a FEC was performed on three separate portions of each sample (total of nine egg counts per foal). Differences in the decision to administer an anthelmintic using the results of a single count (C1), the mean of three (X¯1-3) or nine counts (X¯1-9) and the upper 5% confidence limit of the gamma confidence interval (CI) of the estimate of the distribution mean (µ) from three (UCL1-3) and nine counts (UCL1-9) were determined for a range of egg count thresholds. The UCL1-9 was used as the best estimate of µ, hypothesis testing for treatment and the comparison of treatment decision-making using C1, X¯1-3, X¯1-9 and UCL1-3. The results of this study demonstrated that a point estimate (C1 or X¯1-3) was of limited value for estimating the distribution mean of egg counts in faeces and there was overall poor agreement in treatment decision-making for individual foals using C1 compared with UCL1-9. Of the foals with C1 of zero eggs per gram, 54% and 47% had Parascaris and strongyle eggs in subsequent counts, respectively. The egg density in faeces is inhomogeneous, resulting in considerable variability in egg count results for an individual foal: between faecal piles, different portions of a faecal pile and days. The use of the negative binomial distribution CI for µ takes this variability into account and is recommended for use when interpreting FEC data from horses.


Assuntos
Anti-Helmínticos/uso terapêutico , Infecções por Ascaridida/veterinária , Tomada de Decisão Clínica/métodos , Doenças dos Cavalos/tratamento farmacológico , Contagem de Ovos de Parasitas/veterinária , Animais , Infecções por Ascaridida/tratamento farmacológico , Ascaridoidea , Cavalos
19.
Genet Sel Evol ; 51(1): 32, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242855

RESUMO

BACKGROUND: This study aimed at (1) comparing the accuracies of genomic prediction for parasite resistance in sheep based on whole-genome sequence (WGS) data to those based on 50k and high-density (HD) single nucleotide polymorphism (SNP) panels; (2) investigating whether the use of variants within quantitative trait loci (QTL) regions that were selected from regional heritability mapping (RHM) in an independent dataset improved the accuracy more than variants selected from genome-wide association studies (GWAS); and (3) comparing the prediction accuracies between variants selected from WGS data to variants selected from the HD SNP panel. RESULTS: The accuracy of genomic prediction improved marginally from 0.16 ± 0.02 and 0.18 ± 0.01 when using all the variants from 50k and HD genotypes, respectively, to 0.19 ± 0.01 when using all the variants from WGS data. Fitting a GRM from the selected variants alongside a GRM from the 50k SNP genotypes improved the prediction accuracy substantially compared to fitting the 50k SNP genotypes alone. The gain in prediction accuracy was slightly more pronounced when variants were selected from WGS data compared to when variants were selected from the HD panel. When sequence variants that passed the GWAS [Formula: see text] threshold of 3 across the entire genome were selected, the prediction accuracy improved by 5% (up to 0.21 ± 0.01), whereas when selection was limited to sequence variants that passed the same GWAS [Formula: see text] threshold of 3 in regions identified by RHM, the accuracy improved by 9% (up to 0.25 ± 0.01). CONCLUSIONS: Our results show that through careful selection of sequence variants from the QTL regions, the accuracy of genomic prediction for parasite resistance in sheep can be improved. These findings have important implications for genomic prediction in sheep.


Assuntos
Doenças dos Ovinos/genética , Doenças dos Ovinos/parasitologia , Sequenciamento Completo do Genoma/veterinária , Animais , Austrália , Resistência à Doença/genética , Feminino , Marcadores Genéticos , Testes Genéticos/veterinária , Variação Genética , Estudo de Associação Genômica Ampla/veterinária , Masculino , Contagem de Ovos de Parasitas/veterinária , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Ovinos
20.
Parasitol Res ; 118(8): 2383-2388, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203449

RESUMO

In this study, we evaluated in two trials a protocol designed to protect hair sheep using Barbervax®, a vaccine containing Haemonchus contortus gut membrane glycoprotein antigens. Results indicated that naturally infected vaccinated sheep had significant egg count reductions (90.2 ± 4.03%) compared with controls, although blood parameters remained relatively unchanged probably because the level of challenge was low. Vaccination prevented the periparturient rise in egg shedding of ewes, as well as egg shedding in lambs (37.1%). In the second trial, sheep which were experimentally exposed to higher artificial challenge also showed an efficient response to the vaccine as confirmed by high antibody levels and reduced egg counts and worm burdens (87 ± 5.4% and 79%) respectively. Thus, we believe that the vaccine should be integrated with other management practices for meat hair sheep as it has the advantages of adequate efficacy, reducing anthelmintic utilization and avoiding milk and environmental contamination with chemical residues.


Assuntos
Hemoncose/veterinária , Haemonchus/imunologia , Doenças dos Ovinos/prevenção & controle , Vacinação/métodos , Vacinas/administração & dosagem , Animais , Anticorpos Anti-Helmínticos/imunologia , Feminino , Hemoncose/imunologia , Hemoncose/parasitologia , Hemoncose/prevenção & controle , Haemonchus/genética , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/parasitologia , Vacinas/imunologia
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