Trichostrongylus and Haemonchus anthelmintic resistance in naturally infected sheep from southern Brazil

ABSTRACT The anthelmintic resistance in small ruminants is a common problem and concern worldwide. The aim of this study was to verify anthelmintic treatment efficacy in naturally infected sheep. This study was conducted on nine herds that used the same anthelmintic management for over a year. In each farm, the animals were divided into two groups: untreated control group (n = 5) and treated (n = 10) according to the number of eggs per gram of feces (EPG). The treatment effect was checked based on EPG results and larval culture performed before treatment and 10 days after treatment. Significant differences were not observed (P > 0.05) on EPG results between untreated and treated groups. The coproculture showed that the animals were infected primarily by Haemonchus spp., Trichostrongylus spp., Teladorsagia spp., Cooperia spp. and Oesophagostomum spp. In all farms, anthelmintic resistance by genera Haemonchus and Trichostrongylus was found, but this resistance varied greatly between farms. Haemonchus spp. showed resistance to closantel, levamisole, and albendazole. Trichostrongylus spp. was shown to be resistant to closantel, levamisole, and albendazole. The drugs tested showed to be efficient against the genera Teladorsagia, Cooperia, and Oesophagostomum. Based on these results, we conclude that the anthelmintic resistance to the tested drugs is a problem present in the farms evaluated

Influencia de la infección subclínica por agentes de la fiebre por garrapatas en vacas lecheras

ABSTRACTObjective. The objective of this study was to evaluate the effect of subclinical infection by agents of tick fever in dairy cattle on milk parameters, such as production, composition, and quality. Materials and methods. The study was conducted in a private farm with 75 free-stall-housed dairy cows, from which 37 were evaluated. Monthly, individual milk samples were collected for compositional (fat, lactose, protein, and total solids) and quality (somatic cell counts (SCC)) analyses. In addition, blood samples were collected in order to identify cows that were tick fever-negative and positive by PCR for one or more of the following etiological agents: Babesia bovis, Babesia bigemina and Anaplasma marginale. Results. The results showed increased SCC in positive animals for at least one of the agents when compared to non-infected cows (p<0.05). Milk production was significantly lower in A. marginale positive animals (p<0.05). An increase of about 40% in milk solids content was found in B. bovis positive cows. Also, an increment of approximately 23% in lactose was found on cows positives for B. bigemina. Conclusions. We may conclude that the presence of at least one of these parasites in dairy cattle affects composition or quality of their milk.RESUMENObjetivo. El objetivo de este estudio fue evaluar el efecto de la infección subclínica por agentes de la fiebre por garrapatas en el ganado lechero en producción de leche, la composición y calidad. Materiales y métodos. El estudio se realizó en una finca privada con 75 vacas lecheras alojadas-libre puesto, y de estas se evaluaron 37. Se recogieron muestras de leche individuales mensuales para determinar la composición (grasa, lactosa, proteína y sólidos totales) y la calidad (recuento de células somáticas (SCC)). Además, se recogieron muestras de sangre para identificar vacas que fueron negativas a fiebre de garrapatas y positivos por PCR para uno o más de los siguientes agentes etiológicos: Babesia bovis, Babesia bigemina y Anaplasma marginale. Resultados. Los resultados mostraron un aumento de SCC en los animales positivos, al menos para uno de los agentes cuando se comparó con vacas no infectadas (p<0.05). La producción de leche fue significativamente menor en A. marginale animales positivos (p<0.05). Un aumento de aproximadamente el 40% en el contenido de sólidos de la leche fue encontrado en vacas positivas a B. bovis. También, un incremento de aproximadamente el 23% de la lactosa se encontró en vacas positivas para B. bigemina. Conclusiones. Se puede concluir que la presencia de al menos uno de estos parásitos en el ganado lechero afecta composición o calidad de su leche

Seroprevalence and Risk Factors for Toxoplasma gondii Infection in Goats in Southern Brazil

Background: Toxoplasma gondii is a coccidium, obligate intracellular protozoan, with complex life cycle, affecting virtually all-animal species homoeothermics. Goats are considered susceptible to infection by T. gondii, alterations being reported as pathological fetal death (with subsequent reabsorption), abortion, mummification, and/or the birth of weak goats. Because of these consequences to the animal, the disease is investigated throughout the Brazilian territory. Therefore, the aim of this study was to estimate the seroprevalence of Toxoplasma gondii antibodies and identify risk factors in goats.Materials, Methods & Results: It were collected 654 blood samples from goats distributed on west and mountainous regions of Santa Catarina, Brazil. The number municipalities with the highest numbers of goats were used, with an expected prevalence of 25%, error of 3.2% and confidence level of 95%. All collected samples were tested by indirect immunofluorescence assay (IFA), and 216 (33.02%; 95% CI 29.43-36.77) had antibodies against T. gondii (IFA ≥ 1: 64). Titration 1:64 was observed more frequently (60.2%; 130/216) among seropositive animals. The region with the highest prevalence was the west, i.e., more prone to infections present, with 1.16 more chances than the mountainous region. Animals Boer were more likely to T. gondii infection, being race is a risk factor for disease. When the presence of cats on the property, and these animals had chances of direct contact with cats, the chance of infection increased significantly, being 1.04 times higher went compared with lack of this feature. Regarding age, the animals aged two to five years had higher seropositivity (77.8%). Statistical analysis of effect-cause studies reported a relationship between soropositive animals and neurological problems (P ≤ 0.05), but no relation was found for T. gondii infection and reproductive problems (P > 0.05).Discussion: In the state of Santa Catarina, approximately 33% of the goats were seropositive for T. gondii, according to results of this study. Several other studies has been performed on T. gondii antibodies detection in Brazil, such as Paraná which was 44.68%, in Rio Grande do Norte was 17.1%, in Rio de Janeiro was 29.12%, in Maranhão was 36.95%, in Bahia was 17.4%, in Minas Gerais was 21.4%, in Alagoas was 39% and in Rio Grande do Sul was 30%. The type of food and water source given to the animals was not considered a risk factor for T. gondii infection, although some authors mention that cat feces contaminated with oocysts of the parasite can be more easily ingested in the diet with concentrated (cats have access) and natural water sources. This study showed that 53% of the animals studied had contact with cats, and this variable was considered a risk factor for disease. Statistically, unverified relationship between reproductive problems and goats seropositive for T. gondii, although of approximately 24% of the animals studied showed some reproductive problems (abortion, mummified or heat repetition). In the effect-cause analysis, neurological issues were related to infection by T. gondii in goats, the that can easily be explained because the parasitic cysts of T. gondii may persist in the central nervous system for a long period. The results suggest that infection by T. gondii occurs in goats in two regions of Santa Catarina, in addition, and the risk factors related to disease was between both studied regions, race and presence and contact with cats, just as there is a relation between disease and neurological disorders in goats

Trichostrongylus and Haemonchus anthelmintic resistance in naturally infected sheep from southern Brazil

The anthelmintic resistance in small ruminants is a common problem and concern worldwide. The aim of this study was to verify anthelmintic treatment efficacy in naturally infected sheep. This study was conducted on nine herds that used the same anthelmintic management for over a year. In each farm, the animals were divided into two groups: untreated control group (n = 5) and treated (n = 10) according to the number of eggs per gram of feces (EPG). The treatment effect was checked based on EPG results and larval culture performed before treatment and 10 days after treatment. Significant differences were not observed (P> 0.05) on EPG results between untreated and treated groups. The coproculture showed that the animals were infected primarily byHaemonchus spp., Trichostrongylus spp.,Teladorsagia spp., Cooperia spp. andOesophagostomum spp. In all farms, anthelmintic resistance by genera Haemonchus and Trichostrongylus was found, but this resistance varied greatly between farms.Haemonchus spp. showed resistance to closantel, levamisole, and albendazole. Trichostrongylus spp. was shown to be resistant to closantel, levamisole, and albendazole. The drugs tested showed to be efficient against the genera Teladorsagia,Cooperia, and Oesophagostomum. Based on these results, we conclude that the anthelmintic resistance to the tested drugs is a problem present in the farms evaluated

Influence of subclinical infection by agents of tick fever in milking dairy cows

RESUMEN Objetivo. El objetivo de este estudio fue evaluar el efecto de la infección subclínica por agentes de la fiebre por garrapatas en el ganado lechero en producción de leche, la composición y calidad. Materiales y métodos. El estudio se realizó en una finca privada con 75 vacas lecheras alojadas-libre puesto, y de estas se evaluaron 37. Se recogieron muestras de leche individuales mensuales para determinar la composición (grasa, lactosa, proteína y sólidos totales) y la calidad (recuento de células somáticas (SCC)). Además, se recogieron muestras de sangre para identificar vacas que fueron negativas a fiebre de garrapatas y positivos por PCR para uno o más de los siguientes agentes etiológicos: Babesia bovis, Babesia bigemina y Anaplasma marginale. Resultados. Los resultados mostraron un aumento de SCC en los animales positivos, al menos para uno de los agentes cuando se comparó con vacas no infectadas (p<0.05). La producción de leche fue significativamente menor en A. marginale animales positivos (p<0.05). Un aumento de aproximadamente el 40% en el contenido de sólidos de la leche fue encontrado en vacas positivas a B. bovis. También, un incremento de aproximadamente el 23% de la lactosa se encontró en vacas positivas para B. bigemina. Conclusiones. Se puede concluir que la presencia de al menos uno de estos parásitos en el ganado lechero afecta composición o calidad de su leche.ABSTRACT Objective. The objective of this study was to evaluate the effect of subclinical infection by agents of tick fever in dairy cattle on milk parameters, such as production, composition, and quality. Materials and methods. The study was conducted in a private farm with 75 free-stall-housed dairy cows, from which 37 were evaluated. Monthly, individual milk samples were collected for compositional (fat, lactose, protein, and total solids) and quality (somatic cell counts (SCC)) analyses. In addition, blood samples were collected in order to identify cows that were tick fever-negative and positive by PCR for one or more of the following etiological agents: Babesia bovis, Babesia bigemina and Anaplasma marginale. Results. The results showed increased SCC in positive animals for at least one of the agents when compared to non-infected cows (p<0.05). Milk production was significantly lower in A. marginale positive animals (p<0.05). An increase of about 40% in milk solids content was found in B. bovis positive cows. Also, an increment of approximately 23% in lactose was found on cows positives for B. bigemina. Conclusions. We may conclude that the presence of at least one of these parasites in dairy cattle affects composition or quality of their milk

Occurrence of gastrointestinal parasites in goats from the Western Santa Catarina, Brazil

This study aims to investigate the occurrence of gastrointestinal parasites in goats from the Western Santa Catarina, Brazil. Twenty four farms were analyzed in 17 different municipalities. Animals (n=217) from different production purposes (milk and meat) and age were randomly chosen. Fecal samples were collected from the rectum stored in plastic bottles and transported to the laboratory in portable coolers at 10 °C. The technique of centrifugal flotation with saturated sugar solution was carried out in order to investigate the presence of eggs, cysts, and oocysts of gastrointestinal parasites. In 88.9% of the investigated animals, it was observed that the presence of nematode eggs which belongs to the Strongylida order, after cultivation and larvae identification were identified as Haemonchus spp., Trichostrongylus spp., Teladorsagia spp., Cooperia spp., and Oesophagostomum spp. Eggs of Thysanosoma, Trichuris, Moniezia, and Neoascaris genus were also observed. Additionally, the presence of oocysts of Eimeria spp. and Cryptosporidium spp. as well as cysts of Giardia spp., and Entamoeba spp. were verified. In all the farms evaluated, the animals showed a single or mixed infection, with the highest occurrence of helminths belonging to the Haemonchus and Trichostrongylus genus, as well as the protozoan Eimeria