Search

Global warming is one of the biggest challenge of our times, and significant efforts are being undertaken by academics, industries and other actors to tackle the problem. In the agricultural field precision farming is part of the solution to environmental sustainability and has been researched increasingly in recent years. Indeed, it has the potential to effectively increase livestock yield and decrease production carbon footprint while maintaining welfare. The thesis begins with a review of developments in automated animal monitoring and then moves on to a case study of a health monitoring system for small-ruminant in South Africa. As a demonstration and validation of the potential use case of the system, the method we propose is then applied to another study which aims to study feline health. Lower and Middle Income countries will be strongly affected by the changing climate and its impacts. We devise our method based on two South African small scale sheep and goat farms where assessment of the health status of individual animals is a key step in the timely and targeted treatment of infections, which is critical in the fight against anthelmintic and antimicrobial resistance. The FAMACHA scoring system has been used successfully to detect anaemia caused by infection with the parasitic nematode Haemonchus contortus in small ruminants and is an effective way to identify individuals in need of treatment. However, assessing FAMACHA is labour-intensive and costly as individuals must be manually examined at frequent intervals. Here, we used accelerometers to measure the individual activity of extensively grazed small ruminants exposed to natural Haemonchus contortus worm infection in southern Africa over long time scales (13+ months). When combined with machine learning for missing data imputation and classification, we find that this activity data can predict poorer health as well as those individuals that respond to treatment, with precision up to 80%. We dem

In the midst of anthelmintic resistance, genetic resistance to gastrointestinal nematodes (GIN) in lambs could reduce anthelmintic requirements; therefore, the fecal egg count (FEC) estimated breeding value (EBV) was developed as a measure of genetic merit for parasite burden. One of the first breeds to effectively implement the FEC EBV was Katahdin. To better understand the relationship between the FEC EBV and Haemonchus contortus (Hc) challenge infection, a divergent mating scheme was established with extremely high (High FEC, n = 5) or extremely low (Low FEC, n = 5) FEC EBV Katahdin rams over 2 years. Purebred lambs sired by these rams were born beginning in mid-March and managed on pasture until approximately 120 days of age. A primary infection was established based on FEC during this period. At this point, lambs (n = 109 in Year 1, n = 114 in Year 2) were removed from pasture, treated with an anthelmintic to reduce FEC and transported to the Animal Sciences Farm at West Virginia University. After a rest period, lambs were given 10,000 (Year 1) or 5000 (Year 2) Hc L3. Body weights, FEC, and packed cell volume were collected weekly. Lambs were harvested (n = 60/year) at 5 weeks post-infection. Abomasum worm counts were determined, and worm length was measured using Image J. Sta-tistical analysis was performed by year using the Mixed Model procedure of SAS (SAS Institute, Cary, NC) with fixed effects of sire EBV type. Change in FEC after the prepatent period was greater in Year 1 High FEC-sired lambs compared to Low FEC-sired lambs (210 vs. 34 eggs/g, respectively; P < 0.05). At harvest in Year 2, a greater proportion of Low FEC-than High FEC-sired lambs had worm counts of zero (P < 0.05). Worm fecundity was lower in lambs sired by Low FEC rams (P < 0.05). Taken together, sire selection for low FEC EBV will lower FEC and worm count and improve GIN resistance in progeny.

Haemonchus contortus (HC) is a gastrointestinal nematode of worldwide importance due to the economic losses it causes directly and indirectly in sheep production. Plant extracts rich in secondary metabolites have been proposed as an alternative method of gastrointestinal nematode control in sheep and goats, as they fulfill their biological function and a sustainable environmental accompaniment. The objective of the present experiment was to determine the effect of the hydroalcoholic extract of Leucaena leucocephala leaves (EHLL) on the hatching of Haemonchus contortus in vitro. The extract was obtained by the maceration technique and was subjected to qualitative phytochemical characterization, in which instaurations, phenolic oxydryls, lactones, flavonols, floratanins, coumarins, saponins and aromatic compounds were identified. Concentrations of 100, 90, 80, 70, 60 and 50 mg/mL of the extract were evaluated on the inhibition of egg hatching (IEH) of HC. The hydroalcoholic extract of L. leucocephala showed 71% IEH at 100 mg/mL, an EC50 and EC90 of 52.22 and 302 mg/mL, respectively. The hydroalcoholic extract of L. leucocephala leaves contains bioactive compounds (phenolics, terpenes and flavonoids) that inhibit HC egg hatching with dose-dependent effect. Therefore, EHLL could be considered as an alternative control on this nematode, however, it is necessary to determine the specific metabolite that confers the activity, determine its toxicity and perform in vivo assays., Haemonchus contortus (HC) es un nematodo gastrointestinal de importancia mundial debido a las pérdidas económicas que causa de forma directa e indirecta en la producción ovina. Los extractos de plantas ricos en metabolitos secundarios se han propuesto como un método alternativo de control de nematodos gastrointestinales en ovinos y caprinos, ya que cumplen con su función biológica y un acompañamiento ambiental sustentable. El objetivo del presente experimento fue determinar el efecto del extracto hidroalcohólico de hojas de Leucaena leucocephala (EHLL) sobre la eclosión de Haemonchus contortus in vitro. El extracto se obtuvo mediante la técnica de maceración y fue sometido a una caracterización fitoquímica cualitativa, en la cual se identificaron instauraciones, oxidrilos fenólicos, lactonas, flavonoles, florataninos, cumarinas, saponinas y compuestos aromáticos. Se evaluaron concentraciones de 100, 90, 80, 70, 60 y 50 mg/mL del extracto sobre la inhibición de la eclosión de huevo (IEH) de Haemonchus contortus. El extracto hidroalcohólico de L. leucocephala mostró 71% de IEH a 100 mg/mL, una CE50 y CE90 de 52.22 y 302 mg/mL respectivamente. El extracto hidroalcohólico de hojas de Leucaena leucocephala contiene compuestos bioactivos (fenólicos, terpenos y flavonoides) que inhiben la eclosión de huevos de HC con efecto dosis dependiente. Por lo tanto, el EHLL podría ser considerado como una alternativa de control sobre este nematodo, sin embargo, es necesario determinar el metabolito especifico que confiere la actividad, determinar su toxicidad y realizar ensayos in vivo.

Haemonchus contortus (HC) is a gastrointestinal nematode of worldwide importance due to the economic losses it causes directly and indirectly in sheep production. Plant extracts rich in secondary metabolites have been proposed as an alternative method of gastrointestinal nematode control in sheep and goats, as they fulfill their biological function and a sustainable environmental accompaniment. The objective of the present experiment was to determine the effect of the hydroalcoholic extract of Leucaena leucocephala leaves (EHLL) on the hatching of Haemonchus contortus in vitro. The extract was obtained by the maceration technique and was subjected to qualitative phytochemical characterization, in which instaurations, phenolic oxydryls, lactones, flavonols, floratanins, coumarins, saponins and aromatic compounds were identified. Concentrations of 100, 90, 80, 70, 60 and 50 mg/mL of the extract were evaluated on the inhibition of egg hatching (IEH) of HC. The hydroalcoholic extract of L. leucocephala showed 71% IEH at 100 mg/mL, an EC50 and EC90 of 52.22 and 302 mg/mL, respectively. The hydroalcoholic extract of L. leucocephala leaves contains bioactive compounds (phenolics, terpenes and flavonoids) that inhibit HC egg hatching with dose-dependent effect. Therefore, EHLL could be considered as an alternative control on this nematode, however, it is necessary to determine the specific metabolite that confers the activity, determine its toxicity and perform in vivo assays., Haemonchus contortus (HC) es un nematodo gastrointestinal de importancia mundial debido a las pérdidas económicas que causa de forma directa e indirecta en la producción ovina. Los extractos de plantas ricos en metabolitos secundarios se han propuesto como un método alternativo de control de nematodos gastrointestinales en ovinos y caprinos, ya que cumplen con su función biológica y un acompañamiento ambiental sustentable. El objetivo del presente experimento fue determinar el efecto del extracto hidroalcohólico de hojas de Leucaena leucocephala (EHLL) sobre la eclosión de Haemonchus contortus in vitro. El extracto se obtuvo mediante la técnica de maceración y fue sometido a una caracterización fitoquímica cualitativa, en la cual se identificaron instauraciones, oxidrilos fenólicos, lactonas, flavonoles, florataninos, cumarinas, saponinas y compuestos aromáticos. Se evaluaron concentraciones de 100, 90, 80, 70, 60 y 50 mg/mL del extracto sobre la inhibición de la eclosión de huevo (IEH) de Haemonchus contortus. El extracto hidroalcohólico de L. leucocephala mostró 71% de IEH a 100 mg/mL, una CE50 y CE90 de 52.22 y 302 mg/mL respectivamente. El extracto hidroalcohólico de hojas de Leucaena leucocephala contiene compuestos bioactivos (fenólicos, terpenos y flavonoides) que inhiben la eclosión de huevos de HC con efecto dosis dependiente. Por lo tanto, el EHLL podría ser considerado como una alternativa de control sobre este nematodo, sin embargo, es necesario determinar el metabolito especifico que confiere la actividad, determinar su toxicidad y realizar ensayos in vivo.

Medicinal plants continue to be used alone or in combination with veterinary drugs to treat animal ailments, especially in developing countries where livestock farmers often lack access to modern veterinary services and drugs. In addition, digestive parasitosis remain a major constraint for small ruminant livestock. The objective of this study was to screen the anthelmintic activity of the main plants used in the treatment of the digestive parasitosis of small ruminants in Benin. A total of 40 extracts were prepared using the successive maceration of 10 plants in four solvents of increasing polarity. The phytochemical screening of the plants was performed, and the anthelmintic activity of the extracts was evaluated on L3 larvae of . The cytotoxicity of the 40 extracts was determined on WI38 noncancerous fibroblast cells using the MTT assay, and the total phenol content (TPC), total flavonoid content (TFC), and condensed tannin content (CTC) were quantified in the most effective extracts using colorimetric methods. The results show that the plants contained tannins, flavonoids, and triterpenoids which may, in part, justify their anthelmintic activities. All plants gave active extracts at the highest concentration tested (1200 µg/mL). Methanol (MeOH) extracts were, in general, more effective than the hexane (HEX), dichloromethane (DCM), and aqueous (HO) ones in inhibiting larval migration, with the MeOH extracts of , , and being the most effective. Nevertheless, the MeOH extract of was highly cytotoxic at the concentration of 100 µg/mL. The anthelmintic activity of , , and was studied on for the first time. These results provide scientific information that can be used for better valorization of the anthelmintic potential of the studied plants and to initiate the process of the identification of new anthelmintic molecules.

The objective of this work was to evaluate in vitro efficacy of the quebracho extract (Bioquina®), rich in condensed tannins, against H. contortus in sheep, since there is evidence that condensed tannins from quebracho extract (Schinopsis spp.) can reduce egg excretion, fecundity of parasitic females and the burden of adult gastrointestinal nematode parasites in ruminants. A larval migration inhibition (IML) test was used to evaluate the in vitro anthelmintic effect of the quebracho extract. Infective H. contortus larvae from a susceptible strain to all chemical groups were utilized with 3 extract concentration (5 mg/ml, 15 mg/ml, and 30 mg/ml). The effect of the treatments was submitted to a variance analysis and the estimation of the differences between groups (a posteriori) was evaluated using LSD Fisher test. Results from the in vitro test, revealed significant migration average inhibition percentages that varies from 74% to 80% between 5 mg/ml to 30 mg/ml dilutions. From the analysis of variance, significant differences appear between treatments (p = 0,0494). When performing the mean comparison test, significant differences (p < 0,05) were found between the migration averages at dilutions of 5 mg/ml and 15 mg/ml, and between 5 mg/ml and 30 mg/ml, while no significant differences were detected between the dilution of 15 mg/ml and 30 mg/ml. These results indicated that quebracho extract at the dilutions evaluated showed anthelmintic activity on L3 susceptible to H. contortus., El objetivo fue evaluar in vitro la eficacia del extracto de quebracho (Bioquina®), rico en taninos condensados, en el control de H. contortus de ovinos, dadas las evidencias de que los taninos condensados provenientes del extracto de quebracho (Schinopsis spp.) pueden reducir la excreción de huevos, la fecundidad de las hembras parásitas y la carga de parásitos nematodos gastrointestinales adultos en rumiantes. Se utilizó el test de inhibición de migración larval (IML) a 3 concentraciones diferentes (5 mg/ml, 15 mg/ml y 30 mg/ml) sobre larvas infectantes de H. contortus susceptibles a todos los grupos químicos. El efecto se analizó mediante un análisis de varianza y para la estimación de las diferencias entre grupos (a posteriori) se usó la prueba LSD Fisher. El test in vitro demostró que el extracto de quebracho evaluado redujo aproximadamente entre un 74% y un 80% la migración larval a las concentraciones de entre 5 mg/ml y 30 mg/ml. Del análisis de varianza surgen diferencias significativas entre tratamientos (p = 0,0494). Al realizar la prueba de comparación de medias se evidenciaron diferencias significativas (p < 0,05) entre los promedios de migración a las diluciones de 5 mg/ml y 15 mg/ml y de 5 mg/ml y 30 mg/ml, mientras que no se detectaron diferencias significativas entre la dilución de 15 mg/ml y 30 mg/ml. Estos resultados señalaron que el extracto de quebracho, a las diluciones evaluadas, presentó actividad antihelmíntica sobre larvas L3 susceptibles de H. contortus; sin embargo, se requiere ampliar los estudios in vivo en ovinos.

The objective of this work was to evaluate in vitro efficacy of the quebracho extract (Bioquina®), rich in condensed tannins, against H. contortus in sheep, since there is evidence that condensed tannins from quebracho extract (Schinopsis spp.) can reduce egg excretion, fecundity of parasitic females and the burden of adult gastrointestinal nematode parasites in ruminants. A larval migration inhibition (IML) test was used to evaluate the in vitro anthelmintic effect of the quebracho extract. Infective H. contortus larvae from a susceptible strain to all chemical groups were utilized with 3 extract concentration (5 mg/ml, 15 mg/ml, and 30 mg/ml). The effect of the treatments was submitted to a variance analysis and the estimation of the differences between groups (a posteriori) was evaluated using LSD Fisher test. Results from the in vitro test, revealed significant migration average inhibition percentages that varies from 74% to 80% between 5 mg/ml to 30 mg/ml dilutions. From the analysis of variance, significant differences appear between treatments (p = 0,0494). When performing the mean comparison test, significant differences (p < 0,05) were found between the migration averages at dilutions of 5 mg/ml and 15 mg/ml, and between 5 mg/ml and 30 mg/ml, while no significant differences were detected between the dilution of 15 mg/ml and 30 mg/ml. These results indicated that quebracho extract at the dilutions evaluated showed anthelmintic activity on L3 susceptible to H. contortus., El objetivo fue evaluar in vitro la eficacia del extracto de quebracho (Bioquina®), rico en taninos condensados, en el control de H. contortus de ovinos, dadas las evidencias de que los taninos condensados provenientes del extracto de quebracho (Schinopsis spp.) pueden reducir la excreción de huevos, la fecundidad de las hembras parásitas y la carga de parásitos nematodos gastrointestinales adultos en rumiantes. Se utilizó el test de inhibición de migración larval (IML) a 3 concentraciones diferentes (5 mg/ml, 15 mg/ml y 30 mg/ml) sobre larvas infectantes de H. contortus susceptibles a todos los grupos químicos. El efecto se analizó mediante un análisis de varianza y para la estimación de las diferencias entre grupos (a posteriori) se usó la prueba LSD Fisher. El test in vitro demostró que el extracto de quebracho evaluado redujo aproximadamente entre un 74% y un 80% la migración larval a las concentraciones de entre 5 mg/ml y 30 mg/ml. Del análisis de varianza surgen diferencias significativas entre tratamientos (p = 0,0494). Al realizar la prueba de comparación de medias se evidenciaron diferencias significativas (p < 0,05) entre los promedios de migración a las diluciones de 5 mg/ml y 15 mg/ml y de 5 mg/ml y 30 mg/ml, mientras que no se detectaron diferencias significativas entre la dilución de 15 mg/ml y 30 mg/ml. Estos resultados señalaron que el extracto de quebracho, a las diluciones evaluadas, presentó actividad antihelmíntica sobre larvas L3 susceptibles de H. contortus; sin embargo, se requiere ampliar los estudios in vivo en ovinos.

The ACC-1 family of cys-loop receptors are ligand-gated chloride channels sensitive to acetylcholine (ACh), and are only present in invertebrates. Studies of this family of inhibitory receptors has provided insight into how they bind and respond to ACh in a manner vastly different from nicotinic acetylcholine receptors and appear to be present in tissues that are relevant to anthelmintic action. Here, we have identified two members of the ACC-1 family from the parasitic nematode Haemonchus contortus, Hco-LGC-46 and Hco-ACC-4. Hco-LGC-46 is an ACC subunit that has never been previously expressed and pharmacologically characterized. We found that Hco-LGC-46 when expressed in Xenopus laevis oocytes forms a functional homomeric channel that is responsive to the cholinergic agonists ACh and methylcholine. hco-lgc-46 expressed in a C. elegans lgc-46 null strain (ok2900) suppressed hypersensitivity to aldicarb in a manner similar to cel-lgc-46. It was also found that Hco-LGC-46 assembles with Hco-ACC-1 and produces a receptor that is over 5-fold more sensitive to ACh and responds to the cholinergic agonists methycholine and carbachol. In contrast, the co-expression of Hco-LGC-46 with Hco-ACC-4 resulted in non-functional channels in oocytes. Hco-ACC-4 also appears to form heteromeric channels with a previously characterized subunit, Hco-ACC-2. Co-expression of Hco-ACC-4 with Hco-ACC-2 resulted in a functional heteromeric channel with an EC50 value similar to that of the Hco-ACC-2 homomeric channel. However, the maximum currents generated in the ACC-4/ACC-2 channel were significantly (p < 0.005) lower than those from the ACC-2 homomeric channel. Overall, this is the first report confirming that lgc-46 encodes an acetylcholine-gated chloride channel which when co-expressed with acc-4 results in reduced receptor function or trafficking in oocytes.

Widespread anthelmintic resistance in trichostrongyle nematodes of ruminants has created an urgent need for alternatives to commercial anthelmintics. The bacterium Bacillus thuringiensis (Bt) can produce crystal proteins during sporulation, which can be lethal to insects in multiple orders when ingested. One protein, Cry5B, has demonstrated effectiveness against multiple parasitic nematodes. We hypothesized that Cry5B would be effective against Haemonchus contortus, a highly pathogenic parasite, in sheep. Two experiments tested efficacy of Cry5B in sheep experimentally infected with H. contortus. In the first, a live genetically modified, asporogenous strain of B. thuringiensis expressing cytosolic Cry5B protein (BaCC) was administered orally daily for four days (~40mg/kg Cry5B/day). The mean fecal egg count (FEC) of treated animals was reduced by 94% three days after treatment, and at necropsy the female worm burden was significantly reduced by 98%. In the second experiment inactivated, asporogenous Bt expressing cytosolic Cry5B (IBaCC) was used. Treated animals received 60mg/kg Cry5B, administered daily for three days. By 72 hours after the first treatment FEC was reduced by 91%. Mean total worm burden of treated sheep at necropsy was significantly reduced, with female worms reduced by 95%. A third study tested the effect of BaCC and IBaCC on development of eggs to infective larvae in feces under laboratory and outdoor environmental conditions. Cry5B (15mg) added to feces (10g) reduced numbers of infective larvae by 99% in both environments within 12 days. Cry5B appears to have potential for controlling H. contortus in sheep. All protocols approved by VT IACUC and IBC.

Haemonchus contortus is a critical parasite of goats and sheep. Infection by this blood-feeding gastrointestinal nematode (GIN) parasite has significant health consequences, especially in lambs and kids. The parasite has developed resistance to virtually all known classes of small molecule anthelmintics used to treat it, giving rise in some areas to multidrug resistant parasites that are very difficult to control. Thus, new anthelmintics are urgently needed. Bacillus thuringiensis (Bt) crystal protein 5B (Cry5B), a naturally occurring protein made by a bacterium widely and safely used around the world as a bioinsecticide, represents a new non-small molecule modality for treating GINs. Cry5B has demonstrated anthelmintic activities against parasites of monogastric animals, including some related to those that infect humans, but has not yet been studied in a ruminant. Here we show that H. contortus adults are susceptible to Cry5B protein in vitro. Cry5B produced in its natural form as a sporecrystal lysate against H. contortus infections in goats had no significant efficacy. However, a new Active Pharmaceutical Ingredient (API) paraprobiotic form of Cry5B called IBaCC (Inactivated Bacterium with Cytosolic Crystals), in which Cry5B crystals are encapsulated in dead Bt cell wall ghosts, showed excellent efficacy in vitro against larval stages of H. contortus and relative protein stability in bovine rumen fluid. When given to sheep experimentally infected with H. contortus as three 60 mg/kg doses, Cry5B IBaCC resulted in significant reductions in fecal egg counts (90%) and parasite burdens (72%), with a very high impact on female parasites (96% reduction). These data indicate that Cry5B IBaCC is a potent new treatment tool for small ruminants in the battle against H. contortus.

BackgroundExisting diagnostic methods for the parasitic gastrointestinal nematode, Haemonchus contortus, are time consuming and require specialised expertise, limiting their utility in the field. A practical, on-farm diagnostic tool could facilitate timely treatment decisions, thereby preventing losses in production and flock welfare. We previously demonstrated the ability of visible-near-infrared (Vis-NIR) spectroscopy to detect and quantify blood in sheep faeces with high accuracy. Here we report our investigation of whether variation in sheep type and environment affect the prediction accuracy of Vis-NIR spectroscopy in quantifying blood in faeces.MethodsVisible-NIR spectra were obtained from worm-free sheep faeces collected from different environments and sheep types in South Australia (SA) and New South Wales, Australia and spiked with various sheep blood concentrations. Spectra were analysed using principal component analysis (PCA), and calibration models were built around the haemoglobin (Hb) wavelength region (387-609 nm) using partial least squares regression. Models were used to predict Hb concentrations in spiked faeces from SA and naturally infected sheep faeces from Queensland (QLD). Samples from QLD were quantified using Hemastix® test strip and FAMACHA© diagnostic test scores.ResultsPrincipal component analysis showed that location, class of sheep and pooled versus individual samples were factors affecting the Hb predictions. The models successfully differentiated 'healthy' SA samples from those requiring anthelmintic treatment with moderate to good prediction accuracy (sensitivity 57-94%, specificity 44-79%). The models were not predictive for blood in the naturally infected QLD samples, which may be due in part to variability of faecal background and blood chemistry between samples, or the difference in validation methods used for blood quantification. PCA of the QLD samples, however, identified a difference between samples containing high and

Background: Pregnancy in all animal species requires special care and attention. During this period there is great variation in hematological and biochemical parameters. Many times these parameters are misinterpreted as being obtained from nonpregnant animals with unknown parasite status. Objective: To characterize the hematological, biochemical, and parasitological values within the peripartum period of Santa Ines sheep naturally infected. Methods: For this purpose, 45 ewes were used, with an average body weight of 50 kg. Data were collected during pregnancy, birth and, lactation. Measurements included body weight, body condition score (BCS), evaluation of conjunctive staining, and collection of blood and feces. Results: All variables changed throughout physiological stages. Weight and BCS were different between periods (p<0.05). Fecal egg counts (FEC) were higher in the peripartum period, with a predominance of Haemonchus ssp, 92.85%. Mean hematological and biochemical values varied throughout the study, (p>0.05). Conclusion: The influence of peripartum on the parameters studied should be considered and its use as a reference value. Regarding the physiological variations observed during peripartum, proper animal management could help minimizing the negative effects of parasitic infections on productivity., Antecedentes: A prenhez em todas as espécies requer atenção e cuidados especiais. Neste período há grande variação dos parâmetros hematológicos e bioquímicos dos animais. Muitas vezes estes parâmetros são mal interpretados na realização de diagnósticos por serem baseados em parâmetros de animais saudáveis não gestantes, desconsiderando também a infecção parasitária. Objetivo: Caracterizar os valores hematológicos, bioquímicos e parasitológicos durante o periparto de ovelhas da raça Santa Inês naturalmente infectadas. Métodos: Foram utilizadas quarenta e cinco ovelhas, com peso corporal médio de 50 kg, os animais foram acompanhados durante a prenhez, parto e lactação. As análises compreendiam: pesagem, condição corporal, Famacha©, sangue e fezes. Resultados: Todas as variáveis apresentaram variações concomitantemente ao avanço da gestação, parto e lactação. O peso (PS) e o escore da condição corporal (ECC) apresentaram diferença estatística entre os períodos (p>0,05). As contagens de ovos por grama de fezes (FEC) apresentaram médias mais elevadas no periparto. Os valores hematológicos e bioquímicos também variaram (p>0,05). Conclusão: Devido ao resultado, sugere-se considerar a influência de periparto sobre os parâmetros estudados e a sua utilização como um valor de referência. Tendo em vista as variações fisiológicas devido o período do periparto e as infecções parasitárias o manejo dos animais deve ter como objetivo minimizar os impactos negativos na produção animal., Antecedentes: La preñez en todas las especies animales requiere atención y cuidados especiales. En ese período existe gran variación en los parámetros hematológicos y bioquímicos. Muchas veces estos parámetros son interpretados erróneamente por ser obtenidos de animales no gestantes y con estatus parasitario desconocido. Objetivo: Caracterizar los valores hematológicos, bioquímicos y parasitológicos durante el periparto en ovejas Santa Inés infectadas naturalmente. Métodos: Se utilizaron 45 ovejas, con un peso corporal promedio de 50 kg. la recolección de muestras se realizó durante la gestación, el parto y la lactancia. Se evaluó el peso, la condición corporal, la tinción conjuntiva, y se recolectaron muestras de sangre y heces. Resultados: Todas las variables mostraron variaciones a lo largo de las etapas fisiológicas. La puntuación de peso y condición corporal (BCS) mostró diferencia entre períodos (p<0,05). Los recuentos de huevos fecales (FEC) tuvieron mayores promedios en el periparto, con predominio de Haemonchus ssp, 92,85%. Los valores medios hematológicos y bioquímicos variaron a lo largo del estudio (p<0,05). Conclusiones: Se recomienda considerar la influencia del periparto en los parámetros estudiados y su uso como valor de referencia. Con respecto a las variaciones fisiológicas observadas durante el periparto, el manejo adecuado de los animales podría ayudar a minimizar los efectos negativos de las infecciones parasitarias sobre la productividad.

Background: Pregnancy in all animal species requires special care and attention. During this period there is great variation in hematological and biochemical parameters. Many times these parameters are misinterpreted as being obtained from nonpregnant animals with unknown parasite status. Objective: To characterize the hematological, biochemical, and parasitological values within the peripartum period of Santa Ines sheep naturally infected. Methods: For this purpose, 45 ewes were used, with an average body weight of 50 kg. Data were collected during pregnancy, birth and, lactation. Measurements included body weight, body condition score (BCS), evaluation of conjunctive staining, and collection of blood and feces. Results: All variables changed throughout physiological stages. Weight and BCS were different between periods (p<0.05). Fecal egg counts (FEC) were higher in the peripartum period, with a predominance of Haemonchus ssp, 92.85%. Mean hematological and biochemical values varied throughout the study, (p>0.05). Conclusion: The influence of peripartum on the parameters studied should be considered and its use as a reference value. Regarding the physiological variations observed during peripartum, proper animal management could help minimizing the negative effects of parasitic infections on productivity., Antecedentes: A prenhez em todas as espécies requer atenção e cuidados especiais. Neste período há grande variação dos parâmetros hematológicos e bioquímicos dos animais. Muitas vezes estes parâmetros são mal interpretados na realização de diagnósticos por serem baseados em parâmetros de animais saudáveis não gestantes, desconsiderando também a infecção parasitária. Objetivo: Caracterizar os valores hematológicos, bioquímicos e parasitológicos durante o periparto de ovelhas da raça Santa Inês naturalmente infectadas. Métodos: Foram utilizadas quarenta e cinco ovelhas, com peso corporal médio de 50 kg, os animais foram acompanhados durante a prenhez, parto e lactação. As análises compreendiam: pesagem, condição corporal, Famacha©, sangue e fezes. Resultados: Todas as variáveis apresentaram variações concomitantemente ao avanço da gestação, parto e lactação. O peso (PS) e o escore da condição corporal (ECC) apresentaram diferença estatística entre os períodos (p>0,05). As contagens de ovos por grama de fezes (FEC) apresentaram médias mais elevadas no periparto. Os valores hematológicos e bioquímicos também variaram (p>0,05). Conclusão: Devido ao resultado, sugere-se considerar a influência de periparto sobre os parâmetros estudados e a sua utilização como um valor de referência. Tendo em vista as variações fisiológicas devido o período do periparto e as infecções parasitárias o manejo dos animais deve ter como objetivo minimizar os impactos negativos na produção animal., Antecedentes: La preñez en todas las especies animales requiere atención y cuidados especiales. En ese período existe gran variación en los parámetros hematológicos y bioquímicos. Muchas veces estos parámetros son interpretados erróneamente por ser obtenidos de animales no gestantes y con estatus parasitario desconocido. Objetivo: Caracterizar los valores hematológicos, bioquímicos y parasitológicos durante el periparto en ovejas Santa Inés infectadas naturalmente. Métodos: Se utilizaron 45 ovejas, con un peso corporal promedio de 50 kg. la recolección de muestras se realizó durante la gestación, el parto y la lactancia. Se evaluó el peso, la condición corporal, la tinción conjuntiva, y se recolectaron muestras de sangre y heces. Resultados: Todas las variables mostraron variaciones a lo largo de las etapas fisiológicas. La puntuación de peso y condición corporal (BCS) mostró diferencia entre períodos (p<0,05). Los recuentos de huevos fecales (FEC) tuvieron mayores promedios en el periparto, con predominio de Haemonchus ssp, 92,85%. Los valores medios hematológicos y bioquímicos variaron a lo largo del estudio (p<0,05). Conclusiones: Se recomienda considerar la influencia del periparto en los parámetros estudiados y su uso como valor de referencia. Con respecto a las variaciones fisiológicas observadas durante el periparto, el manejo adecuado de los animales podría ayudar a minimizar los efectos negativos de las infecciones parasitarias sobre la productividad.

The present study explored the anthelmintic effects of condensed tannins (CT) in carob (Ceratonia siliqua) pods fed to sheep against gastrointestinal nematodes. Three independent in vivo trials tested whether i) carob pod (CaBP)-containing feed had an anthelmintic effect and if yes, which was the optimal concentration in the diet; ii) whether this effect could be attributed to tannins through the polyethylene glycol (PEG) test and iii) whether there were any synergistic effects when combined with another tannin-containing feed (e.g. sainfoin). In all trials 6-month old nematode-naive lambs, experimentally infected with both Haemonchus contortus and Trichostrongylus colubriformis, were used. Faecal egg counts (FEC) were performed regularly and at the end of each trial adult worm counts (AWC) and female worm fecundity were recorded. In trial 1, 35 lambs (five groups of seven lambs) were fed different CaBP concentrations ranging from 0% to 12 % w/w. FEC declined up to 39.2 % only in the group fed with 12 %CaBP, while a declining trend (P < 0.06) was demonstrated for the AWC of T. colubriformis, which was associated with the increasing concentration of CaBP in feed. Female worm fecundity was reduced in groups fed CaBP for both parasites, however this was only significant for H. contortus (P < 0.001), in a dose dependent manner. In trial 2, four groups of six infected lambs each were used, which received the carob diets CaBP or CaBP + PEG, and the tannin-free diets with or without PEG (C or C + PEG). Results showed that FEC of Groups C, C + PEG, and CaBP + PEG were comparable throughout the trial, while the group receiving only CaBP showed lower FEC from DAY 25 onwards. AWC showed a reduction (67.7 %) only for H. contortus (P < 0.03). Reversal of the anthelmintic effect of CaBP after PEG administration suggested that CT contributed to the anthelmintic action. However, no effect of CaBP was observed on T. colubriformis AWC and on female worm fecundity for both

The present study explored the anthelmintic effects of condensed tannins (CT) in carob (Ceratonia siliqua) pods fed to sheep against gastrointestinal nematodes. Three independent in vivo trials tested whether i) carob pod (CaBP)-containing feed had an anthelmintic effect and if yes, which was the optimal concentration in the diet; ii) whether this effect could be attributed to tannins through the polyethylene glycol (PEG) test and iii) whether there were any synergistic effects when combined with another tannin-containing feed (e.g. sainfoin). In all trials 6-month old nematode-naive lambs, experimentally infected with both Haemonchus contortus and Trichostrongylus colubriformis, were used. Faecal egg counts (FEC) were performed regularly and at the end of each trial adult worm counts (AWC) and female worm fecundity were recorded. In trial 1, 35 lambs (five groups of seven lambs) were fed different CaBP concentrations ranging from 0% to 12 % w/w. FEC declined up to 39.2 % only in the group fed with 12 %CaBP, while a declining trend (P < 0.06) was demonstrated for the AWC of T. colubriformis, which was associated with the increasing concentration of CaBP in feed. Female worm fecundity was reduced in groups fed CaBP for both parasites, however this was only significant for H. contortus (P < 0.001), in a dose dependent manner. In trial 2, four groups of six infected lambs each were used, which received the carob diets CaBP or CaBP + PEG, and the tannin-free diets with or without PEG (C or C + PEG). Results showed that FEC of Groups C, C + PEG, and CaBP + PEG were comparable throughout the trial, while the group receiving only CaBP showed lower FEC from DAY 25 onwards. AWC showed a reduction (67.7 %) only for H. contortus (P < 0.03). Reversal of the anthelmintic effect of CaBP after PEG administration suggested that CT contributed to the anthelmintic action. However, no effect of CaBP was observed on T. colubriformis AWC and on female worm fecundity for both

Haemonchus contortus is a critical parasite of goats and sheep. Infection by this blood-feeding gastrointestinal nematode (GIN) parasite has significant health consequences, especially in lambs and kids. The parasite has developed resistance to virtually all known classes of small molecule anthelmintics used to treat it, giving rise in some areas to multidrug resistant parasites that are very difficult to control. Thus, new anthelmintics are urgently needed. Bacillus thuringiensis (Bt) crystal protein 5B (Cry5B), a naturally occurring protein made by a bacterium widely and safely used around the world as a bioinsecticide, represents a new non-small molecule modality for treating GINs. Cry5B has demonstrated anthelmintic activities against parasites of monogastric animals, including some related to those that infect humans, but has not yet been studied in a ruminant. Here we show that H. contortus adults are susceptible to Cry5B protein in vitro. Cry5B produced in its natural form as a sporecrystal lysate against H. contortus infections in goats had no significant efficacy. However, a new Active Pharmaceutical Ingredient (API) paraprobiotic form of Cry5B called IBaCC (Inactivated Bacterium with Cytosolic Crystals), in which Cry5B crystals are encapsulated in dead Bt cell wall ghosts, showed excellent efficacy in vitro against larval stages of H. contortus and relative protein stability in bovine rumen fluid. When given to sheep experimentally infected with H. contortus as three 60 mg/kg doses, Cry5B IBaCC resulted in significant reductions in fecal egg counts (90%) and parasite burdens (72%), with a very high impact on female parasites (96% reduction). These data indicate that Cry5B IBaCC is a potent new treatment tool for small ruminants in the battle against H. contortus.

Widespread anthelmintic resistance in trichostrongyle nematodes of ruminants has created an urgent need for alternatives to commercial anthelmintics. The bacterium Bacillus thuringiensis (Bt) can produce crystal proteins during sporulation, which can be lethal to insects in multiple orders when ingested. One protein, Cry5B, has demonstrated effectiveness against multiple parasitic nematodes. We hypothesized that Cry5B would be effective against Haemonchus contortus, a highly pathogenic parasite, in sheep. Two experiments tested efficacy of Cry5B in sheep experimentally infected with H. contortus. In the first, a live genetically modified, asporogenous strain of B. thuringiensis expressing cytosolic Cry5B protein (BaCC) was administered orally daily for four days (~40mg/kg Cry5B/day). The mean fecal egg count (FEC) of treated animals was reduced by 94% three days after treatment, and at necropsy the female worm burden was significantly reduced by 98%. In the second experiment inactivated, asporogenous Bt expressing cytosolic Cry5B (IBaCC) was used. Treated animals received 60mg/kg Cry5B, administered daily for three days. By 72 hours after the first treatment FEC was reduced by 91%. Mean total worm burden of treated sheep at necropsy was significantly reduced, with female worms reduced by 95%. A third study tested the effect of BaCC and IBaCC on development of eggs to infective larvae in feces under laboratory and outdoor environmental conditions. Cry5B (15mg) added to feces (10g) reduced numbers of infective larvae by 99% in both environments within 12 days. Cry5B appears to have potential for controlling H. contortus in sheep. All protocols approved by VT IACUC and IBC.

El presente trabajo tiene como objetivo determinar la Prevalencia de Haemonchus contortus en los ovinos criollos en la Comunidad de Coporaque, Distrito de Coporaque, Provincia Caylloma, Región Arequipa. Con un universo de 232 ovinos criollos. Este universo de ovinos fue determinado en el Distrito de Coporaque en el mes de marzo del 2019. Donde 18 propietarios se inscribieron. El muestreo realizado fue aleatoriamente estratificado por conveniencia. Que fue de una población de 150 muestras de ovinos criollos en donde se subdividió por categorías o clase animal: 63 borregas, 12 carneros, 28 borreguillas, 13 carnerillos y 34 corderos. Para dicho trabajo se identificó los ovinos a estudiar, seguidamente con la ayuda de un guante látex, previa sujeción, las muestras fueron extraídas directamente de la ampolla rectal de los ovinos, luego fueron colocados en las bolsas de polipropileno a la vez se rotulo, seguidamente fueron enviados al laboratorio con el protocolo de envió correspondiente. Las 150 muestras fecales fueron enviadas y analizadas por el laboratorio LABVETSUR, donde se utilizó el método de flotación para el recuento de huevos. Los resultados de las muestras enviadas para determinar la prevalencia de Haemonchus contortus fueron: 5% de prevalencia y 95% salió negativo, donde las categorías de ovinos con mayor incidencia fueron de borregas, carneros y carnerillo los cuales tienen una prevalencia de 8% de 63 borregas, 12 carneros y 13 carnerillos muestreados respectivamente. La categoría corderos resulto negativo con 0% de prevalencia de Haemonchus contortus. Palabras claves: Haemonchus contortus, ovinos criollos.

El presente trabajo tiene como objetivo determinar la Prevalencia de Haemonchus contortus en los ovinos criollos en la Comunidad de Coporaque, Distrito de Coporaque, Provincia Caylloma, Región Arequipa. Con un universo de 232 ovinos criollos. Este universo de ovinos fue determinado en el Distrito de Coporaque en el mes de marzo del 2019. Donde 18 propietarios se inscribieron. El muestreo realizado fue aleatoriamente estratificado por conveniencia. Que fue de una población de 150 muestras de ovinos criollos en donde se subdividió por categorías o clase animal: 63 borregas, 12 carneros, 28 borreguillas, 13 carnerillos y 34 corderos. Para dicho trabajo se identificó los ovinos a estudiar, seguidamente con la ayuda de un guante látex, previa sujeción, las muestras fueron extraídas directamente de la ampolla rectal de los ovinos, luego fueron colocados en las bolsas de polipropileno a la vez se rotulo, seguidamente fueron enviados al laboratorio con el protocolo de envió correspondiente. Las 150 muestras fecales fueron enviadas y analizadas por el laboratorio LABVETSUR, donde se utilizó el método de flotación para el recuento de huevos. Los resultados de las muestras enviadas para determinar la prevalencia de Haemonchus contortus fueron: 5% de prevalencia y 95% salió negativo, donde las categorías de ovinos con mayor incidencia fueron de borregas, carneros y carnerillo los cuales tienen una prevalencia de 8% de 63 borregas, 12 carneros y 13 carnerillos muestreados respectivamente. La categoría corderos resulto negativo con 0% de prevalencia de Haemonchus contortus. Palabras claves: Haemonchus contortus, ovinos criollos.

El presente trabajo tiene como objetivo determinar la Prevalencia de Haemonchus contortus en los ovinos criollos en la Comunidad de Coporaque, Distrito de Coporaque, Provincia Caylloma, Región Arequipa. Con un universo de 232 ovinos criollos. Este universo de ovinos fue determinado en el Distrito de Coporaque en el mes de marzo del 2019. Donde 18 propietarios se inscribieron. El muestreo realizado fue aleatoriamente estratificado por conveniencia. Que fue de una población de 150 muestras de ovinos criollos en donde se subdividió por categorías o clase animal: 63 borregas, 12 carneros, 28 borreguillas, 13 carnerillos y 34 corderos. Para dicho trabajo se identificó los ovinos a estudiar, seguidamente con la ayuda de un guante látex, previa sujeción, las muestras fueron extraídas directamente de la ampolla rectal de los ovinos, luego fueron colocados en las bolsas de polipropileno a la vez se rotulo, seguidamente fueron enviados al laboratorio con el protocolo de envió correspondiente. Las 150 muestras fecales fueron enviadas y analizadas por el laboratorio LABVETSUR, donde se utilizó el método de flotación para el recuento de huevos. Los resultados de las muestras enviadas para determinar la prevalencia de Haemonchus contortus fueron: 5% de prevalencia y 95% salió negativo, donde las categorías de ovinos con mayor incidencia fueron de borregas, carneros y carnerillo los cuales tienen una prevalencia de 8% de 63 borregas, 12 carneros y 13 carnerillos muestreados respectivamente. La categoría corderos resulto negativo con 0% de prevalencia de Haemonchus contortus. Palabras claves: Haemonchus contortus, ovinos criollos.

BackgroundExisting diagnostic methods for the parasitic gastrointestinal nematode, Haemonchus contortus, are time consuming and require specialised expertise, limiting their utility in the field. A practical, on-farm diagnostic tool could facilitate timely treatment decisions, thereby preventing losses in production and flock welfare. We previously demonstrated the ability of visible-near-infrared (Vis-NIR) spectroscopy to detect and quantify blood in sheep faeces with high accuracy. Here we report our investigation of whether variation in sheep type and environment affect the prediction accuracy of Vis-NIR spectroscopy in quantifying blood in faeces.MethodsVisible-NIR spectra were obtained from worm-free sheep faeces collected from different environments and sheep types in South Australia (SA) and New South Wales, Australia and spiked with various sheep blood concentrations. Spectra were analysed using principal component analysis (PCA), and calibration models were built around the haemoglobin (Hb) wavelength region (387-609 nm) using partial least squares regression. Models were used to predict Hb concentrations in spiked faeces from SA and naturally infected sheep faeces from Queensland (QLD). Samples from QLD were quantified using Hemastix® test strip and FAMACHA© diagnostic test scores.ResultsPrincipal component analysis showed that location, class of sheep and pooled versus individual samples were factors affecting the Hb predictions. The models successfully differentiated 'healthy' SA samples from those requiring anthelmintic treatment with moderate to good prediction accuracy (sensitivity 57-94%, specificity 44-79%). The models were not predictive for blood in the naturally infected QLD samples, which may be due in part to variability of faecal background and blood chemistry between samples, or the difference in validation methods used for blood quantification. PCA of the QLD samples, however, identified a difference between samples containing high and

The study investigated anthelmintic activity of Plectranthus barbatus (leaves) used by traditional medicine practitioners of Migori County using adult Haemonchus contortus worm as a model. 50 gm of ground powder of Plectranthus barbatus (leaves) was extracted separately with 300 ml each of methanol, acetone and water. The yields of the extracts were 3.32 gm, 3.98 gm and 3.36 gm for methanol, acetone and water respectively. The anthelmintic activity of 6.25 mg/ml, 12.5 mg/ml and 25 mg/ml concentrations of aqueous, acetone and methanol crude extracts of Plectranthus barbatus (leaves), were compared with the effect produced by the standard reference drug albendazole with Phosphate Buffered Saline (PBS) used as a negative control. Death of Haemonchus contortus worm was determined within a period of 24 hrs. Plectranthus barbatus (leaves) extract had mean mortality of 0-16.7 % at 6.25 mg/ml; 3.3-26.7 % at 12.5 mg/ml; 6.7-33.3 % at 25 mg/ml. All the extracts contained tannins only.

The study investigated anthelmintic activity of Plectranthus barbatus (leaves) used by traditional medicine practitioners of Migori County using adult Haemonchus contortus worm as a model. 50 gm of ground powder of Plectranthus barbatus (leaves) was extracted separately with 300 ml each of methanol, acetone and water. The yields of the extracts were 3.32 gm, 3.98 gm and 3.36 gm for methanol, acetone and water respectively. The anthelmintic activity of 6.25 mg/ml, 12.5 mg/ml and 25 mg/ml concentrations of aqueous, acetone and methanol crude extracts of Plectranthus barbatus (leaves), were compared with the effect produced by the standard reference drug albendazole with Phosphate Buffered Saline (PBS) used as a negative control. Death of Haemonchus contortus worm was determined within a period of 24 hrs. Plectranthus barbatus (leaves) extract had mean mortality of 0-16.7 % at 6.25 mg/ml; 3.3-26.7 % at 12.5 mg/ml; 6.7-33.3 % at 25 mg/ml. All the extracts contained tannins only.

An appraisal of current literature (Chapter 1) revealed that many parasitic worms are pathogens of animals, causing major diseases and socioeconomic losses worldwide. Efforts to control roundworms (nematodes) are often compromised by widespread resistance to currently used treatments. Thus, there is a clear need to work toward new interventions, preferably based on a deep understanding of the molecular biology of nematodes and/or the relationship that they have with their host animals. The predominant focus of the present thesis was on exploring aspects of the developmental biology of parasitic nematodes using advanced molecular (‘omic) and bioinformatic technologies, with an emphasis on the barber’s pole worm (Haemonchus contortus) - one of the most economically important parasites of ruminant livestock. The specific aims were: (1) to establish molecular data sets (resources) for H. contortus; (2) to explore RNA transcription and protein expression profiles in the developmental transition from free-living to parasitic larvae of H. contortus under well-defined conditions in vitro; (3) to construct dauer-like signalling pathways in H. contortus and some other nematodes (ascaridoids); and (4) to elucidate dauer-like signalling and the involvement of bile acid-like dafachronic acids during nematode development. All of these aims were achieved. Addressing aim 1, comprehensive molecular (transcriptomic, proteomic and lipidomic) resources were established for H. contortus using advanced nucleic acid sequencing or mass spectrometry techniques (Chapters 2-4). Addressing aim 2, these resources were utilised for in-depth explorations of molecular changes during the developmental switch from the free-living to the parasitic stage of H. contortus (Chapter 5). This work revealed extensive alterations in transcription and protein expression. There was a discordance between the mRNA transcription and protein expression changes, which appeared to relate to microRNA regulation at th

The present thesis focused on discovering new candidate compounds in natural products against economically important parasitic worms of livestock to circumvent current problems associated with resistance to commercially-available drugs (anthelmintics) (cf. Chapter 1). One of the most pathogenic parasites of small ruminants, Haemonchus contortus (barber’s pole worm), was used as the screening tool. This whole-organism bioassay was used to identify active compounds/extracts that reduced motility and/or development or altered the morphology (phenotype) of H. contortus larvae in vitro. Selected compounds were purified from active extracts using a bioassay-guided fractionation approach. The screening of two compound libraries containing a total of 1,000 natural products, natural product-inspired or synthetic compounds identified 34 compounds with notable activity against H. contortus (Chapters 2 and 3). Most of the ‘hits’ (n=32) identified from the first library were analogues of arylpyrrole (a natural product scaffold), while deguelin and rotenone (two plant rotenoids) were identified from the second library. Encouraged by these findings, a library of 7,500 extracts from different plant species was screened (Chapter 4). This screen identified three active extracts from the leaves and roots of Cryptocarya novoguineensis and the roots of Piper methysticum. Bioassay-guided fractionation of active extracts yielded four known alpha-pyrones, namely goniothalamin from C. novoguineensis, and dihydrokavain, desmethoxyyangonin and yangonin (= kavalactones) from P. methysticum. Three kavalactones induced a lethal ‘evisceration’ phenotype in treated larvae of H. contortus, and had limited toxicity on mammalian epithelial (MCF10A) cells. This is the first report on the activity of such natural compounds on a parasitic nematode of animals. The work was extended to explore compounds from Australian marine species. A library of 2,000 extracts from marine invertebrates was screened (Cha

Among the main health problems for sheep production are gastrointestinal parasites, of which the most important nematode is Haemonchus contortus. Current control strategies focus on the effectiveness, along with the low impact on the ecosystem. The study of the integral control of parasites allows the investigation of alternatives with probable anthelmintic effect, such as the use of papaya (Carica papaya) seeds. This study aimed at evaluating the in vitro effect of hydroalcoholic and ethanolic extracts of papaya seeds on eggs and larvae of H. contortus. The study was carried out with the equipment and facilities of Laboratory 3 of the Multidisciplinary Research Unit at the Facultad de Estudios Superiores Cuautitlán, UNAM. The extracts were prepared through maceration in solvent. A sheep was inoculated with 5000 L3 of H. contortus, a strain isolated and maintained in the facilities. Fecal samples were collected, and eggs were recovered for the hatch inhibition assay. The eggs and L3 were pretreated with hydroalcoholic and ethanolic extract of papaya seed (2.5 mg/ml), distilled water, ethanol 90 %, and levamisole (7.5 mg/ml). The abomasal explants technique was used to evaluate the effect of the extracts on L3 and its association to the abomasal mucosa. An ANOVA was performed for repeated samples using the Statgraphics program. The ethanolic extract of the papaya seed inhibited 92 % of hatching, and the hydroalcoholic extract 50 % (p <0.05). In the case of the explants, the ethanolic extract showed 10 % of the larvae not associated with the abomasal tissue, followed by the hydroalcoholic extract with 60 % of non-associated larvae (p<0.05). In conclusion, the ethanolic extract has an effect on eggs, while the hydroalcoholic extract inhibits the association to the abomasal tissue., Entre los principales problemas sanitarios para la producción ovina están los parásitos gastroentéricos; de ellos, el más importante es Haemonchus contortus. Las estrategias actuales de control enfocan la eficacia, junto con el bajo o nulo impacto al ecosistema; el estudio del control integral de parásitos permite la investigación de alternativas con probable efecto antihelmíntico, entre ellas el uso de semilla de papaya (Carica papaya). El objetivo de este trabajo fue evaluar el efecto in vitro de los extractos hidroalcohólico y etanólico de la semilla de papaya (C. papaya) sobre huevos y larvas de H. contortus. El trabajo se llevó a cabo con el equipo e instalaciones del Laboratorio 3 de la Unidad de Investigación Multidisciplinaria en la Facultad de Estudios Superiores Cuautitlán, UNAM. Se elaboraron los extractos por medio de maceración en solvente. Se inoculó un ovino con 5000 larvas de tercer estadio (L3) de H. contortus, cepa aislada y mantenida en dichas instalaciones. Se tomaron muestras de materia fecal y se recuperaron huevos para el ensayo de inhibición de la eclosión. Los huevos y las L3 fueron pretratados con extracto hidroalcohólico y etanólico de semilla de papaya (2.5 mg/ml), agua destilada, etanol 90 % y levamisol (7.5 mg/ml). Se efectuó la técnica de explantes abomasales, evaluando el efecto de los extractos sobre las L3 y su asociación a la mucosa abomasal. Se realizó un ANOVA para muestras repetidas por medio del programa Statgraphics. El extracto etanólico de semilla de papaya mostró el 92 % de inhibición de la eclosión; el extracto hidroalcohólico mostró 50 % (p<0.05). En el caso de los explantes, el extracto etanólico mostró el 10 % de larvas no asociadas al tejido abomasal, seguido por el extracto hidroalcohólico, con el 60 % de larvas no asociadas (p<0.05). Se concluye que el extracto etanólico tiene efecto sobre huevos, mientras que el extracto hidroalcohólico inhibe la asociación al tejido abomasal.

Among the main health problems for sheep production are gastrointestinal parasites, of which the most important nematode is Haemonchus contortus. Current control strategies focus on the effectiveness, along with the low impact on the ecosystem. The study of the integral control of parasites allows the investigation of alternatives with probable anthelmintic effect, such as the use of papaya (Carica papaya) seeds. This study aimed at evaluating the in vitro effect of hydroalcoholic and ethanolic extracts of papaya seeds on eggs and larvae of H. contortus. The study was carried out with the equipment and facilities of Laboratory 3 of the Multidisciplinary Research Unit at the Facultad de Estudios Superiores Cuautitlán, UNAM. The extracts were prepared through maceration in solvent. A sheep was inoculated with 5000 L3 of H. contortus, a strain isolated and maintained in the facilities. Fecal samples were collected, and eggs were recovered for the hatch inhibition assay. The eggs and L3 were pretreated with hydroalcoholic and ethanolic extract of papaya seed (2.5 mg/ml), distilled water, ethanol 90 %, and levamisole (7.5 mg/ml). The abomasal explants technique was used to evaluate the effect of the extracts on L3 and its association to the abomasal mucosa. An ANOVA was performed for repeated samples using the Statgraphics program. The ethanolic extract of the papaya seed inhibited 92 % of hatching, and the hydroalcoholic extract 50 % (p <0.05). In the case of the explants, the ethanolic extract showed 10 % of the larvae not associated with the abomasal tissue, followed by the hydroalcoholic extract with 60 % of non-associated larvae (p<0.05). In conclusion, the ethanolic extract has an effect on eggs, while the hydroalcoholic extract inhibits the association to the abomasal tissue., Entre los principales problemas sanitarios para la producción ovina están los parásitos gastroentéricos; de ellos, el más importante es Haemonchus contortus. Las estrategias actuales de control enfocan la eficacia, junto con el bajo o nulo impacto al ecosistema; el estudio del control integral de parásitos permite la investigación de alternativas con probable efecto antihelmíntico, entre ellas el uso de semilla de papaya (Carica papaya). El objetivo de este trabajo fue evaluar el efecto in vitro de los extractos hidroalcohólico y etanólico de la semilla de papaya (C. papaya) sobre huevos y larvas de H. contortus. El trabajo se llevó a cabo con el equipo e instalaciones del Laboratorio 3 de la Unidad de Investigación Multidisciplinaria en la Facultad de Estudios Superiores Cuautitlán, UNAM. Se elaboraron los extractos por medio de maceración en solvente. Se inoculó un ovino con 5000 larvas de tercer estadio (L3) de H. contortus, cepa aislada y mantenida en dichas instalaciones. Se tomaron muestras de materia fecal y se recuperaron huevos para el ensayo de inhibición de la eclosión. Los huevos y las L3 fueron pretratados con extracto hidroalcohólico y etanólico de semilla de papaya (2.5 mg/ml), agua destilada, etanol 90 % y levamisol (7.5 mg/ml). Se efectuó la técnica de explantes abomasales, evaluando el efecto de los extractos sobre las L3 y su asociación a la mucosa abomasal. Se realizó un ANOVA para muestras repetidas por medio del programa Statgraphics. El extracto etanólico de semilla de papaya mostró el 92 % de inhibición de la eclosión; el extracto hidroalcohólico mostró 50 % (p<0.05). En el caso de los explantes, el extracto etanólico mostró el 10 % de larvas no asociadas al tejido abomasal, seguido por el extracto hidroalcohólico, con el 60 % de larvas no asociadas (p<0.05). Se concluye que el extracto etanólico tiene efecto sobre huevos, mientras que el extracto hidroalcohólico inhibe la asociación al tejido abomasal.

Small ruminant farmers have a constant battle with infections of gastrointestinal nematode (GIN) within their grazing sheep and goats. Haemonchus contortus, more commonly called the barber pole worm, is the most pathogenic parasite that feeds on blood, eventually causing anemia and weight loss, and even death. Ruminants have a four-chambered stomach consisting of the reticulum, rumen, omasum, and abomasum. The life cycle of H. contortus begins in the abomasum where the adult worms reside and reproduce, and the resulting eggs are shed out in the feces. The eggs hatch to yield larvae, which grow to the infective third stage (L3). The H. contortus L3 are consumed by grazing sheep and goats. The L3 have a protective sheath covering that must be shed within the rumen in order for the larva to continue development into adults within the abomasum. The shedding of the sheath is called ‘exsheathment’ and is a critical part in the life cycle of H. contortus. Haemonchus contortus have become increasingly resistant to the chemical dewormers (anthelmintics) commonly used to control infections. Increasing anthelmintic resistance in these GIN creates a need for alternative methods of GIN control. Plant secondary compounds have demonstrated anti-parasitic activity and are currently the focus of many studies. Stored larvae are commonly utilized in in vitro and in vivo assays of plant secondary compounds. Although researchers typically do not use L3 that have been stored longer than three months, the effect of season on the viability and exsheathment of stored L3 is unknown. The objective of this study is to determine the effect of season on in vitro and in vivo exsheathment efficacy of stored H. contortus L3. Four donor rams were infected with 10,000 H. contortus L3 on the autumn equinox (fall, n=2) and on the winter solstice (winter, n=2). After the infection reached maturity (~ 4 weeks), fecal matter was collected and cultured for 10 days and the resulting L3 were harvested and st

Makrocykliska laktoner (ML) är ett viktig anthelmintika som används mycket. Den utbredda användningen har lett till att nematoder har utvecklat läkemedelsresistens. För att bekämpa det måste nya metoder tas fram för att hitta genetiska markörer som på ett tidigt stadie kan identifiera resistenta nematoder. Därför pågår mycket forskning om bakomliggande mekanismer för resistens mot ML hos parasiter. Syftet med det här litteraturarbetet är att ta reda på vilka mekanismer för resistens mot ML som nematoderna Caenorhabditis elegans, Cooperia oncophora och Haemonchus contortus har utvecklat. Jag kommer även att jämföra om det finns ett samband för hur dessa tre nematoder utvecklar resistens. C. elegans som är en frilevande nematod och är lätt att odla i laboratoriemiljö, och används därför som en modellorganism. C. oncophora och H. contortus är parasiter som infekterar nötkreatur och får och de kan inte odlas i laboratoriemiljö. Arbetet jämför även olika mekanismer för resistens mot ivermektin (IVM) och moxidektin (MOX) som är två olika substanser inom ML-gruppen. ML verkar genom att binda till glutamatreglerade kloridjonkanaler (GluCl) och leder till paralys hos nematoden genom influx av kloridjoner. GluCl är en jonkanal som finns hos nematoder och den består av fem olika subenheter som kodas av fem olika gener. Forskarna antar att GluCl är en möjlig mekanism för resistens eftersom det är en verkningsmekanism för ML. Flera studier på detta har visat att det är vissa gener som är mer relevanta som mekanism för resistens än andra. De är framför allt genen avr-14 hos de tre nematoderna och även generna avr-15 och glc-1 hos C. elegans och glc-5 hos H. contortus. ATP-binding cassette (ABC) transportörer transporterar olika substrat över membran. Det finns många olika gener som styr ABC transportörer. Det antas att ABC transportörer är en mekanism för resistens då de pumpar ML över membranet och därigenom sänks läkemedelskoncentrationen och nematoderna klarar av behandlingen., Macrocyclic lactones (ML) are an important anthelmintic with high usage. The high usage has led to nematodes developing drug resistance. To combat this new methods are needed to find genetic markers that can identify resistant nematodes at an early stage. Because of this a lot of research is done on the underlying mechanisms of resistance to ML in parasites. The purpose of this review is to ascertain the mechanisms of resistance against ML that Caenorhabditis elegans, Cooperia oncophora and Haemonchus contortus have developed. I also compare these mechanisms to ascertain if there are any connections between how the three nematodes develop resistance. C. elegans is a free living nematode that is easy to grow in a laboratory environment, and is therefore used as a model organism. C. oncophora and H. contortus are parasites that infect cattle and sheep and cannot be grown in a laboratory environment. This review also compares ivermectin (IVM) and moxidectin (MOX) which are substrates in the ML-group. The mode of action of ML is through glutamate-gated chloride channels (GluCl) and leads to paralysis in the nematode through influx of chloride ions. GluCl is an ion channel found in nematodes and it consists of five different subunits encoded by five different genes. The scientists assume that GluCl is a good candidate of resistance because that is the binding site of ML. Studies have shown that there are some genes that are more relevant as a mechanism of resistance than others. These are in particular the gene avr-14 in all three nematodes and also the genes avr-15 and glc-1 in C. elegans and glc-5 in H. contortus. ATP-binding cassette (ABC) transporters transport different substrates over membranes. There exists many different genes that control ABC transporters. It is assumed that ABC transporters are a mechanism of resistance because they pump ML across the membrane and thereby lower the drug concentration in the parasite and the nematodes survive the treatment. It h

Background: It is necessary to identify phenotypic traits related to natural resistance against gastrointestinal nematodes (GIN) in order to know the host immunity status in productive ewes. Objetive: To determine haematological and immunological parameters (IgA and IgG) during pregnancy and lactation in Blackbelly ewes naturally infected with GIN Methods: The number of eggs per gram (EPG), packed cell volume (% PCV), plasmatic protein (PP), and peripheral eosinophils were determined during eight months. In addition, sera and saliva samples were collected to establish IgG and IgA kinetics by indirect enzyme-linked immunosorbent assay (ELISA). Results: The results showed 2,592 ± 2,403 EPG and 22.2 ± 4.0% PCV during lactation and 595 ± 901 EPG and 25.1 ± 2.5% PCV during pregnancy. A higher percentage of Trichostrongylus colubriformis larvae were observed in pregnancy (84 to100%) than in lactation (36 to 44%). The IgA activity in serum samples showed a marked reduction (from 80 to 10%) during lambing for both Haemonchus contortus and T. colubriformis antigens. In saliva samples, IgA activity with regard to the standard decreased from 56% at 60 days to 30% at 45 days before lambing and remained low for 45 days during lactation (23 to 32% activity). The eosinophils numbers were 2.0 x 109 cells L-1 in pregnancy and remained low at 0.7 x 109 cells L-1 in lactation. Conclusion: The studied variables reflect the breakdown of immunity against GIN in Blackbelly ewes before and after lambing., Antecedentes: A identificação de traços fenotípicos relacionados à resistência natural contra nematóides gastrintestinais (GIN) é necessária para saber a imunidade do hospedeiro em ovelhas produtivas. Objetivo: Determinar parâmetros hematológicos e imunológicos (IgA e IgG) em períodos de gestação e lactação em ovelhas Blackbelly naturalmente infectados com GIN. Métodos: O número de ovos por grama (EPG), volume empacotado de células (% PCV), proteína plasmática (PP) e eosinófilos periféricos foram determinados durante oito meses. Além disso, as amostras de soro e saliva foram recolhidas para determinar a cinética de IgG e IgA por ELISA indireto. Resultados: Os resultados mostraram 2.592 ± 2.403 EPG e 22,2 ± 4,0% PCV durante a lactação e 595 ± 901 EPG e 25,1 ± 2,5% PCV durante a gravidez. A percentagem mais elevada de larvas de Trichostrongylus colubriformis foi observada na gravidez (84 a 100%) do que na lactação (36 a 44%). A atividade de IgA em amostras de soro mostrou uma redução acentuada (80 a 10%) durante o parto nos antígenos de Haemonchus contortus e T. colubriformis. Em amostras de saliva, a atividade de IgA diminuiu de 56 a 30% do dia 60 ao 45 antes do parto e permaneceu baixa por 45 dias durante a lactação (atividade de 23 a 32%). O número de eosinófilos foi de 2,0 x 109 células L-1 na gravidez e manteve-se baixo, com 0,7 x 109 células L-1 na lactação. Conclusaõ: As variáveis estudadas refletem a quebra da imunidade contra GIN em ovelhas Blackbelly antes e depois do parto., Antecedentes: La identificación del fenotipo relacionado con la resistencia contra nematodos gastrointestinales (GIN) es necesaria para conocer la inmunidad del huésped en ovejas en producción. Objetivo: Determinar los parámetros hematológicos e inmunológicos (IgA e IgG) en gestación y lactancia en ovejas Blackbelly infectadas naturalmente con GIN. Métodos: Se determinó el número de huevos por gramo de heces (EPG), se identificaron las larvas y se registró el porcentaje del volumen celular aglomerado (% PCV), proteína plasmática (PP) y eosinófilos periféricos durante ocho meses. Además, se colectó suero y saliva para determinar la cinética de IgG e IgA por medio de un ensayo inmuno-enzimático (ELISA) indirecto. Resultados: Los resultados mostraron 2.592 ± 2.403 EPG y 22,2 ± 4,0% PCV durante la lactancia y 595 ± 901 EPG y 25,1 ± 2,5% PCV durante la gestación. Se observó un mayor porcentaje de larvas de Trichostrongylus colubriformis en gestación (84 a 100%) que en lactancia (36 a 44%). La actividad de la IgA en las muestras de suero mostró una marcada reducción después del parto para ambos antígenos de Haemonchus contortus y T. colubriformis (80 a 10%). En saliva, la actividad de la IgA disminuyó de 56 a 30% del día 60 al 45 antes del parto y se mantuvo baja en los primeros 45 días de la lactancia (actividad de 23 a 32%). El número de eosinófilos fue de 2,0 x 109 células L-1 durante la gestación, y se redujo a 0,7 x 109 células L-1 en la lactancia. Conclusión: Las variables estudiadas reflejan la ruptura de la inmunidad contra GIN en ovejas Blackbelly antes y después del parto.

RESUMENDentro de las enfermedades que ocasionan un gran deterioro en la producción caprina, las parasitosis por los nematodes gastrointestinales tienen una importancia preponderante, especialmente las producidas por Haemonchus contortus, especie dominante en el centro de la Argentina y de mayor significación por las pérdidas que ocasiona. Con el objetivo de evaluar el sistema de control FAMACHA© (FAM) en la detección de anemia en cabras de San Luis (Argentina), se muestrearon 42 animales en un establecimiento de producción de cabritos ubicado en Villa Mercedes (SL). Durante los meses estivales se determinó el color de la mucosa ocular según la escala de la carta de colores FAM con cinco grados, el hematocrito (Hem), la condición corporal (CC), el conteo de huevos (hpg) y las especies de nematodos presentes. Las observaciones se realizaron sobre dos grupos de 21 animales: el G1 sin desparasitar al comienzo del ensayo y el G2 desparasitado al comienzo de la estación estival (manejo del establecimiento) con Ricobendazol al 15 % ajustada a dosis caprina. Los animales con los grados FAM 4 y 5 fueron desparasitados con la misma droga y dosis. Se estimó la correlación existente entre los grados de FAM, Hem y CC, como la sensibilidad (S), especificidad (E) y los valores predictivos positivo (VP+) y negativo (VP-) usando el Hem ≤19% para determinar anemia. Los coprocultivos demostraron un predominio de Haemonchus superior al 64% promedio del período. Los grados de FAM 2 y 3 fueron los más numerosos y con hematocritos más alto que los de la bibliografía, mientras que los grados 4 y 5 se encontraron dentro de los parámetros de hematocritos anémicos. Los coeficientes de correlación (p<0,01) fueron: entre Hem-FAM r= - 0,56 y r= - 0,50, entre el hpg-FAM y r= 0,46 y r= 0,29 y entre CC- FAM r= - 0,53 y r= - 0,35 respectivamente para G1y G2. La S en ambos grupos fue mayor (100%) cuando se usaron los criterios FAM 3, 4 y 5 como positivos, sin embargo la E de ambos

The FAMACHA system was introduced to the U.S. just over 10 yr ago to allow selective deworming of lambs with anemia associated with Haemonchus contortus and retard the development of anthelmintic resistance. The FAMACHA system was initially developed as a predictor of packed cell volume (PCV), but correlations between FAMACHA and fecal egg counts (FEC) have also been reported. It is important to understand factors that influence FAMACHA scores among farms to improve management of gastrointestinal nematodes. The objectives of this study were therefore to quantify associations between FAMACHA scores, FEC, BW, and age in Katahdin lambs at 2 different measurement times in 8 flocks in the eastern U.S., and to assess consistency of relationships between FAMACHA and FEC among flocks. Data came from 1,644 Katahdin lambs from 7 flocks sampled at approximately 90 d of age, and 1,295 lambs from 6 flocks sampled at approximately 120 d of age over a 5 yr period. Residual correlations among log-transformed FEC (LFEC), FAMACHA scores, BW, and lamb ages at each measurement time were determined. Repeatability of each variable was also determined as residual correlations among repeated measures. At both 90 and 120 d of age, correlations of FAMACHA scores with LFEC and BW were significant (P < 0.001), but numerically modest (0.25 and -0.16, respectively at 90 d; 0.31 and -0.16, respectively at 120 d), demonstrating that higher FAMACHA scores were associated with higher FEC and more likely to be observed in lighter lambs. A small negative correlation was observed between FAMACHA score and lamb age (r = -0.05, P = 0.05, 90 d; r = -0.11, P < 0.001, 120 d) indicating that younger lambs were more likely to have elevated FAMACHA scores. Thus, younger and lighter lambs will likely be more susceptible to parasitism and may need to be managed more diligently than older or heavier lambs. In addition, FAMACHA scores have potential to improve breeding value estimates in programs designed to genet

Background: It is necessary to identify phenotypic traits related to natural resistance against gastrointestinal nematodes (GIN) in order to know the host immunity status in productive ewes. Objetive: To determine haematological and immunological parameters (IgA and IgG) during pregnancy and lactation in Blackbelly ewes naturally infected with GIN Methods: The number of eggs per gram (EPG), packed cell volume (% PCV), plasmatic protein (PP), and peripheral eosinophils were determined during eight months. In addition, sera and saliva samples were collected to establish IgG and IgA kinetics by indirect enzyme-linked immunosorbent assay (ELISA). Results: The results showed 2,592 ± 2,403 EPG and 22.2 ± 4.0% PCV during lactation and 595 ± 901 EPG and 25.1 ± 2.5% PCV during pregnancy. A higher percentage of Trichostrongylus colubriformis larvae were observed in pregnancy (84 to100%) than in lactation (36 to 44%). The IgA activity in serum samples showed a marked reduction (from 80 to 10%) during lambing for both Haemonchus contortus and T. colubriformis antigens. In saliva samples, IgA activity with regard to the standard decreased from 56% at 60 days to 30% at 45 days before lambing and remained low for 45 days during lactation (23 to 32% activity). The eosinophils numbers were 2.0 x 109 cells L-1 in pregnancy and remained low at 0.7 x 109 cells L-1 in lactation. Conclusion: The studied variables reflect the breakdown of immunity against GIN in Blackbelly ewes before and after lambing., Antecedentes: A identificação de traços fenotípicos relacionados à resistência natural contra nematóides gastrintestinais (GIN) é necessária para saber a imunidade do hospedeiro em ovelhas produtivas. Objetivo: Determinar parâmetros hematológicos e imunológicos (IgA e IgG) em períodos de gestação e lactação em ovelhas Blackbelly naturalmente infectados com GIN. Métodos: O número de ovos por grama (EPG), volume empacotado de células (% PCV), proteína plasmática (PP) e eosinófilos periféricos foram determinados durante oito meses. Além disso, as amostras de soro e saliva foram recolhidas para determinar a cinética de IgG e IgA por ELISA indireto. Resultados: Os resultados mostraram 2.592 ± 2.403 EPG e 22,2 ± 4,0% PCV durante a lactação e 595 ± 901 EPG e 25,1 ± 2,5% PCV durante a gravidez. A percentagem mais elevada de larvas de Trichostrongylus colubriformis foi observada na gravidez (84 a 100%) do que na lactação (36 a 44%). A atividade de IgA em amostras de soro mostrou uma redução acentuada (80 a 10%) durante o parto nos antígenos de Haemonchus contortus e T. colubriformis. Em amostras de saliva, a atividade de IgA diminuiu de 56 a 30% do dia 60 ao 45 antes do parto e permaneceu baixa por 45 dias durante a lactação (atividade de 23 a 32%). O número de eosinófilos foi de 2,0 x 109 células L-1 na gravidez e manteve-se baixo, com 0,7 x 109 células L-1 na lactação. Conclusaõ: As variáveis estudadas refletem a quebra da imunidade contra GIN em ovelhas Blackbelly antes e depois do parto., Antecedentes: La identificación del fenotipo relacionado con la resistencia contra nematodos gastrointestinales (GIN) es necesaria para conocer la inmunidad del huésped en ovejas en producción. Objetivo: Determinar los parámetros hematológicos e inmunológicos (IgA e IgG) en gestación y lactancia en ovejas Blackbelly infectadas naturalmente con GIN. Métodos: Se determinó el número de huevos por gramo de heces (EPG), se identificaron las larvas y se registró el porcentaje del volumen celular aglomerado (% PCV), proteína plasmática (PP) y eosinófilos periféricos durante ocho meses. Además, se colectó suero y saliva para determinar la cinética de IgG e IgA por medio de un ensayo inmuno-enzimático (ELISA) indirecto. Resultados: Los resultados mostraron 2.592 ± 2.403 EPG y 22,2 ± 4,0% PCV durante la lactancia y 595 ± 901 EPG y 25,1 ± 2,5% PCV durante la gestación. Se observó un mayor porcentaje de larvas de Trichostrongylus colubriformis en gestación (84 a 100%) que en lactancia (36 a 44%). La actividad de la IgA en las muestras de suero mostró una marcada reducción después del parto para ambos antígenos de Haemonchus contortus y T. colubriformis (80 a 10%). En saliva, la actividad de la IgA disminuyó de 56 a 30% del día 60 al 45 antes del parto y se mantuvo baja en los primeros 45 días de la lactancia (actividad de 23 a 32%). El número de eosinófilos fue de 2,0 x 109 células L-1 durante la gestación, y se redujo a 0,7 x 109 células L-1 en la lactancia. Conclusión: Las variables estudiadas reflejan la ruptura de la inmunidad contra GIN en ovejas Blackbelly antes y después del parto.

RESUMENDentro de las enfermedades que ocasionan un gran deterioro en la producción caprina, las parasitosis por los nematodes gastrointestinales tienen una importancia preponderante, especialmente las producidas por Haemonchus contortus, especie dominante en el centro de la Argentina y de mayor significación por las pérdidas que ocasiona. Con el objetivo de evaluar el sistema de control FAMACHA© (FAM) en la detección de anemia en cabras de San Luis (Argentina), se muestrearon 42 animales en un establecimiento de producción de cabritos ubicado en Villa Mercedes (SL). Durante los meses estivales se determinó el color de la mucosa ocular según la escala de la carta de colores FAM con cinco grados, el hematocrito (Hem), la condición corporal (CC), el conteo de huevos (hpg) y las especies de nematodos presentes. Las observaciones se realizaron sobre dos grupos de 21 animales: el G1 sin desparasitar al comienzo del ensayo y el G2 desparasitado al comienzo de la estación estival (manejo del establecimiento) con Ricobendazol al 15 % ajustada a dosis caprina. Los animales con los grados FAM 4 y 5 fueron desparasitados con la misma droga y dosis. Se estimó la correlación existente entre los grados de FAM, Hem y CC, como la sensibilidad (S), especificidad (E) y los valores predictivos positivo (VP+) y negativo (VP-) usando el Hem ≤19% para determinar anemia. Los coprocultivos demostraron un predominio de Haemonchus superior al 64% promedio del período. Los grados de FAM 2 y 3 fueron los más numerosos y con hematocritos más alto que los de la bibliografía, mientras que los grados 4 y 5 se encontraron dentro de los parámetros de hematocritos anémicos. Los coeficientes de correlación (p<0,01) fueron: entre Hem-FAM r= - 0,56 y r= - 0,50, entre el hpg-FAM y r= 0,46 y r= 0,29 y entre CC- FAM r= - 0,53 y r= - 0,35 respectivamente para G1y G2. La S en ambos grupos fue mayor (100%) cuando se usaron los criterios FAM 3, 4 y 5 como positivos, sin embargo la E de ambos

Gastrointestinal nematodes (GINs), Haemonchus contortus, are a major health problem in goat production. Resistance to H. contortus, the most prevalent GIN in Uganda, was studied among three indigenous goat breeds to assess their differences. Twelve male goats of each breed approximately 7 months old of small East African (SEA), Mubende, and Kigezi goats from smallholder farmers in Arua, Mubende, and Kabale were assembled for the study. At the station, they were dewormed with a combination therapy of the broad-spectrum dewormers closantel and albendazole to free the goats of gastrointestinal parasites. During experimentation, the goats were kept indoors and ad libitum fed on clean banana peels and napier grass. On attainment of zero-worm-egg status, the goats were artificially infected with 18,000 third-stage (L3) larvae of H. contortus prepared according to Baermann’s procedure. Data were collected on fecal egg count (FEC), packed cell volume (PCV), and body weight (BW) on a 2-week basis until 12 weeks post infection and carcass weight and total worm count (WC) in the abomasum at termination of the experiment. The data on FEC, PCV, and BW were subjected to repeated-measure analysis of variance and the others by one-way analysis of variance. FEC between breeds was only significantly different at 12 weeks post infection (p = 0.04). Generally, higher FEC was recorded in Kigezi compared to SEA and Mubende goats. Carcass weight was significantly different among breeds (p < 0.05), with Mubende having the highest carcass weight, followed by Kigezi and SEA. PCV and daily weight gains were significantly different between breeds (p < 0.05). WC was not significantly different between the breeds. FEC and PCV were weakly significant at later stages of the experiment with higher parasite burden suggesting potential variation in resistance to H. contortus. These differences could be exploited in designing breeding programs with disease resistance in indigenous goat breeds.

The FAMACHA system was introduced to the U.S. just over 10 yr ago to allow selective deworming of lambs with anemia associated with Haemonchus contortus and retard the development of anthelmintic resistance. The FAMACHA system was initially developed as a predictor of packed cell volume (PCV), but correlations between FAMACHA and fecal egg counts (FEC) have also been reported. It is important to understand factors that influence FAMACHA scores among farms to improve management of gastrointestinal nematodes. The objectives of this study were therefore to quantify associations between FAMACHA scores, FEC, BW, and age in Katahdin lambs at 2 different measurement times in 8 flocks in the eastern U.S., and to assess consistency of relationships between FAMACHA and FEC among flocks. Data came from 1,644 Katahdin lambs from 7 flocks sampled at approximately 90 d of age, and 1,295 lambs from 6 flocks sampled at approximately 120 d of age over a 5 yr period. Residual correlations among log-transformed FEC (LFEC), FAMACHA scores, BW, and lamb ages at each measurement time were determined. Repeatability of each variable was also determined as residual correlations among repeated measures. At both 90 and 120 d of age, correlations of FAMACHA scores with LFEC and BW were significant (P < 0.001), but numerically modest (0.25 and -0.16, respectively at 90 d; 0.31 and -0.16, respectively at 120 d), demonstrating that higher FAMACHA scores were associated with higher FEC and more likely to be observed in lighter lambs. A small negative correlation was observed between FAMACHA score and lamb age (r = -0.05, P = 0.05, 90 d; r = -0.11, P < 0.001, 120 d) indicating that younger lambs were more likely to have elevated FAMACHA scores. Thus, younger and lighter lambs will likely be more susceptible to parasitism and may need to be managed more diligently than older or heavier lambs. In addition, FAMACHA scores have potential to improve breeding value estimates in programs designed to genet

El nuevo enfoque de control integrado de parásitos obliga a buscar alternativas que consideren el medioambiente, es decir, sostenibles y sustentables. El objetivo de este trabajo fue fraccionar el extracto etanólico de la planta Artemisia cina, obtener artemisininas y conocer el efecto de estas sobre la capacidad de asociación de las L3 de Haemonchus contortus en explantes abomasales. El extracto etanólico se fraccionó por medio de la metodología establecida para Artemisia japónica, y se identificaron las artemisininas por medio de cromatografía en capa fina, teniendo como referencia artemisininas comerciales. Las artemisininas se utilizaron sobre L3 desenvainada, se realizó la técnica de explantes abomasales por triplicado y se compararon así: levamisol (7.5 mg/ml), artemisinina comercial (1 mg/ml), agua y seis diferentes fracciones de A. cina a dosis de 1 mg/ml: Ac3k, Ac3b, Ac3a, Ac3h, Ac3i, Ac4b. No se obtuvieron diferencias significativas entre las fracciones de A. cina y artemisinina comercial (p>0.05). Se concluye que no existió efecto de las artemisininas obtenidas del extracto etanólico de A. cina sobre la capacidad de asociación de las L3 de H. contortus al tejido abomasal. Es importante continuar con más estudios de la artemisinina para determinar sobre qué fase del parásito afecta su viabilidad.

El nuevo enfoque de control integrado de parásitos obliga a buscar alternativas que consideren el medioambiente, es decir, sostenibles y sustentables. El objetivo de este trabajo fue fraccionar el extracto etanólico de la planta Artemisia cina, obtener artemisininas y conocer el efecto de estas sobre la capacidad de asociación de las L3 de Haemonchus contortus en explantes abomasales. El extracto etanólico se fraccionó por medio de la metodología establecida para Artemisia japónica, y se identificaron las artemisininas por medio de cromatografía en capa fina, teniendo como referencia artemisininas comerciales. Las artemisininas se utilizaron sobre L3 desenvainada, se realizó la técnica de explantes abomasales por triplicado y se compararon así: levamisol (7.5 mg/ml), artemisinina comercial (1 mg/ml), agua y seis diferentes fracciones de A. cina a dosis de 1 mg/ml: Ac3k, Ac3b, Ac3a, Ac3h, Ac3i, Ac4b. No se obtuvieron diferencias significativas entre las fracciones de A. cina y artemisinina comercial (p>0.05). Se concluye que no existió efecto de las artemisininas obtenidas del extracto etanólico de A. cina sobre la capacidad de asociación de las L3 de H. contortus al tejido abomasal. Es importante continuar con más estudios de la artemisinina para determinar sobre qué fase del parásito afecta su viabilidad.

There is a substantial need to develop new medicines against parasitic diseases via public-private partnerships. Based on high throughput phenotypic screens of largely protozoal pathogens and bacteria, the Medicines for Malaria Venture (MMV) has recently assembled an open-access 'Pathogen Box' containing 400 well-curated chemical compounds. In the present study, we tested these compounds for activity against parasitic stages of the nematode Haemonchus contortus (barber's pole worm). In an optimised, whole-organism screening assay, using exsheathed third-stage (xL3) and fourth-stage (L4) larvae, we measured the inhibition of larval motility, growth and development of H. contortus. We also studied the effect of the 'hit' compound on mitochondrial function by measuring oxygen consumption. Among the 400 Pathogen Box compounds, we identified one chemical, called tolfenpyrad (compound identification code: MMV688934) that reproducibly inhibits xL3 motility as well as L4 motility, growth and development, with IC50 values ranging between 0.02 and 3 μM. An assessment of mitochondrial function showed that xL3s treated with tolfenpyrad consumed significantly less oxygen than untreated xL3s, which was consistent with specific inhibition of complex I of the respiratory electron transport chain in arthropods. Given that tolfenpyrad was developed as a pesticide and has already been tested for absorption, distribution, excretion, biotransformation, toxicity and metabolism, it shows considerable promise for hit-to-lead optimisation and/or repurposing for use against H. contortus and other parasitic nematodes. Future work should assess its activity against hookworms and other pathogens that cause neglected tropical diseases.

Haemonchus contortus, de rode lebmaagworm, is in Nederland de belangrijkste wormsoort bij kleine herkauwers. Afhankelijk van de weersomstandigheden trad haemonchose in het verleden vooral op vanaf eind juni tot begin september, maar geleidelijk is deze periode verlengd van mei tot soms begin oktober. Dit artikel geeft u de achtergrondinformatie om haemonchose te voorkomen.

The aim of this project was to investigate host-parasite interactions, which might lead to alternate strategies to control the sheep abomasal nematode Haemonchus contortus. The project focused on two aspects of host parasite interactions: the initiation of host pathology and suppression of host immune responses associated with the onset of infection. Adult H. contortus ES products increased the permeability of Caco-2 cell monolayers and this increase could be blocked by single chain antibodies against ES products displayed on phage. Recombinant H. contortus enolase may be one of the active components of ES as it mimicked the action of ES products on Caco-2 cells. This is the first study of immunomodulation by adult H. contortus ES products of the phenotypic and functional properties of human monocyte-derived dendritic cells (mdDCs). Incubation with ES products resulted in semi-maturation of mdDCs, with weak up-regulation of the co-stimulatory molecules CD40 and CD80 and increased surface expression of the tolerogenic markers CD32, CD305 and galectin-1. The highly variable responses of mdDCs of individual donors biased the group data, particularly in response to co-stimulation with ES products and LPS. This highlights genetic diversity in the immune system and possible difficulties in developing worm-based therapies. The blastogenic activities of cells from lymph nodes collected from two groups of infected and vaccinated sheep were measured by 3H-thymidine uptake after exposure to ConA or ES products. The Stimulation Index (SI) with ConA was 1 0-fold higher in cells from the older animals. Cells only from younger infected sheep had a reduced response to ConA and vaccinated groups with reduced parasite burdens had the highest Sl. There was little response to ES products in older sheep, but in younger animals there was a trend for lymphocyte Sl to be greater with 10% ES in sheep with the fewest parasites. These experiments show that H. contortus ES products may facilit

The blood feeding nematode Haemonchus contortus infects the abomasum of small ruminants and compartment three (C-3) of camelids. Heavy infections may cause severe anemia and death. Alpacas were first introduced into the U.S. in the 1980s. Although not true ruminants, alpacas may become infected with H. contortus and develop the same clinical signs as sheep and goats. Even though alpacas may become infected with the parasite, prior research by Hill et al. (1993) and Green et al. (1996) indicates alpacas may be more resistant to parasitic infection because they found lower numbers of eggs in the feces of alpacas compared to small ruminants. For our research, we hypothesized that given the same exposure to experimental infection, alpacas would be less susceptible than sheep to H. contortus. Experiment 1 was conducted with adult male alpacas (23) and sheep (12) housed in pens to prevent additional exposure to H. contortus. All animals were dewormed orally with a cocktail of fenbendazole, levamisole, and ivermectin. Haemonchus contortus infective larvae were administered orally to alpacas and rams in the following groups:1) 20,000 larvae as a single dose (bolus, n=6 both alpacas and sheep), 2) 20,000 larvae in daily doses of 4,000 larvae for 5 days (trickle, n=5 for alpacas, n=6 for sheep). Two additional groups of alpacas (n=6 each) received either 50,000 larvae as a bolus infection, or in daily doses of 10,000 larvae for 5 days (trickle). Fecal egg counts (FEC) were determined every 2 days from 14 to 42 days post infection (PI) and then at 5 day intervals until day 62 PI. Packed cell volume (PCV), FAMACHA scores, weight, and body condition scores were evaluated weekly. In general, mean FEC were lower in alpacas than sheep (p<0.01), and mean alpaca PCV was affected less by infection than sheep PCV. Experiment 1 results are consistent with our hypothesis that alpacas are less susceptible to H. contortus infection than sheep; however we were unable to determine whether al

Parasitangrepp är en av de vanligaste och allvarligaste orsakerna till produktionsbortfall hos får och nöt. Akut sjukdom till följd av parasitangrepp uppstår ofta plötsligt och med hög mortalitet. Kroniska parasitangrepp kan vara svåra att upptäcka, då djuren inte alltid uppvisar symptom, men dessa angrepp kan ge följder över en längre tidsperiod med bl.a. nedsatt produktion av mjölk och ull samt sämre tillväxt av lamm och kalvar. Inom modern djurproduktion idag är den primära nematodkontrollen att begränsa antalet infektiösa larver på betet genom strategisk användning av anthelmintikum kombinerat med beteshygien. På grund av att vi länge förlitat oss på enbart anthelmintikum som behandling har detta nu fått konsekvenser i form av resistens hos flera arter. I dagsläget finns inget effektivt alternativ till kemisk kontroll av helminter hos idisslare, och resistens utgör därmed ett stort hot både mot djurvälfärd och produktion. Syftet med denna litteratursammanställning var att undersöka hur stor förekomsten av denna resistens är i Sverige, vilka arter som är resistenta samt vad som selekterar för uppkomsten av resistens och hur vi kan undvika det. Sammanställningen visar att resistensläget i Sverige fortfarande är gott jämfört med andra länder. Resistensen är mer utbredd hos får, då exempelvis benzimidazolresistens hos Haemonchus contortus förekom hos 5% av flockarna jämfört med nöt där det endast kunnat påvisas några få fall av ivermektinresistens hos adulter av arten Cooperia onchophora. Dock bör detta inte ses som en anledning till att ignorera resistensfrågan, då en resistent stam som väl uppkommit är ett allvarligare och långt mer avancerat problem att lösa än att arbeta i före-byggande syfte. Andra arter som det påvisats resistens hos i andra länder är Ostertagia ostertagi, Trichostrongylus spp. och Teladorsagia circumcincta, vilka också finns upptagna i denna sammanställning. Sammanfattningsvis så krävs det att forskningen på alternativa metoder fortsätter, då, Parasites are a common and serious cause of production losses for the farming industry. Acute symptoms due to high parasite burden are emerging fast and the mortality rate is high. Chronic diseases due to parasite infection could be hard to detect because of the lack symptoms or discomfort of the animals. Chronic parasite infections could cause losses over an extended period of time, including lowered milk and wool production as well as slower growth rate of lambs and calves. Today the primarily control of parasites are with the use anthelmintics and/or grazing strategies. The objectives of parasite control are to lower the worm burdens on pasture and thus lower the risk of major infections in the animals. Because of the frequent use of anthelmintics in both past and present, resistance have developed in several parasite species. Currently, no effective alternatives to anthelmintics are available and the resistance in parasites is thus a major threat to both animal welfare and the farming industry. The objective of this literature summary is to investigate how resistance develop (and how we can avoid it), which parasite species that are resistant and to which extent the resistance is present in Sweden. The summary shows that the situation of anthelmintic resistance in sheep and cattle in Sweden is still acceptable and low, in comparison to other countries. Resistance is more widespread among sheep, where Haemonchus contortus is the predominant species, which is resistant in 5% of tested flocks against Benzimidazoles. In cattle, only a few adult of the Cooperia oncho-phora species have been found to be resistant to Ivermectin. Though, it is not an acute problem today, there is no reason to ignore that this might become a problem in the future. An increase of resistant parasites are a serious problem therefore attention must be paid to profylactical work to prevent the resistance to develop. Other species known to be resistant to anthelmintic in other countries are Os

De schapensector gaat de parasitaire resistentie-ontwikkeling terugdringen. Ze wil dat doen door verbetering van de preventie en de bestrijding van maagdarmwormen. Experts hebben in 2013 een literatuurstudie uitgevoerd. Hierin zijn de belangrijkste binnen- en buitenlandse innovatieve ontwikkelingen voor verlaging van de infectiedruk opgenomen en vertaald naar toepasbaarheid onder de Nederlandse omstandigheden. Bekeken zijn de gebieden fokkerij, voeding, vaccinatie, beweiding, inzet van natuurlijke middelen en diagnostiek. In deze brochure zijn de belangrijkste bevindingen samengevat.

Op één of mogelijk twee schapenbedrijven in Nederland is resistentie van de rode lebmaagworm voor monepantel aangetoond. Gezien de korte tijd dat dit ontwormingsmiddel op de Nederlandse markt beschikbaar is, is de snelheid waarmee de resistentie zich heeft kunnen ontwikkelen, opmerkelijk.