Thais Ferreira Feitosa

Biological control of goat gastrointestinal helminthiasis by Duddingtonia flagrans in a semi-arid region of the northeastern Brazil.

The aim of this study was to test a pellet formulation in a sodium alginate matrix of Duddingtonia flagrans in the biological control of goat gastrointestinal helminths kept in a native pasture in a semi-arid region of Paraíba state, northeastern Brazil. An area of 2.4 ha was divided into three paddocks, where groups of seven goats ware formed. Each group received the following treatments during the months of March to August 2011: D. flagrans group, received 3g of pellets containing D. flagrans (AC001) for each 10 kg/l.w., twice a week; Moxidectin 0.2% group, received 0.2mg/kg of Moxidectin 0.2% orally, every 30 days; Control group, received 3g of pellets without fungi per 10 kg/l.w., twice a week. Each month, a tracer goat was placed in each group for 30 days and then sacrificed and necropsied. The D. flagrans group showed a greater reduction in EPG, increased weight gain, higher rates of packed cell volume and lower parasitic load burden in the tracer goats compared to Moxidectin 0.2% and Control groups. D. flagrans was efficient in controlling goat gastrointestinal helminthiasis in a semi-arid region of northeastern Brazil.

FAMACHA(©) method as an auxiliary strategy in the control of gastrointestinal helminthiasis of dairy goats under semiarid conditions of Northeastern Brazil.

This study aimed to evaluate the utilization of FAMACHA(©) method as an auxiliary strategy to use the individual identification for the selective control of gastrointestinal helminthiasis in naturally infected dairy goats. The experiment was conducted on 63 farms in the towns of Passagem, Quixabá and Cacimba de Areia, semiarid region of the Paraíba state, Brazil. Fifty animals were used on each farm, being visited tree farms per month, totaling 1800 animals, between May 2009 and April 2010. The animals received no anthelmintic treatment for at least four months prior to the farm visits. All animals were subjected to parasitological faecal collection, blood sampling for packed cell volume and the visual/selective exam of the eye colour through the FAMACHA(©) method. Larvae culture was performed in every assessment on each farm. Haemonchus sp. was the most prevalent helminth (80.1%) on larval cultures. The use of this method allowed a reduction of 79.2% on anthelmintic application in dairy goats. The FAMACHA(©) method proved to be a viable auxiliary strategy to control gastrointestinal helminthiasis of dairy goats from a resource-poor area in the semiarid region of the Paraíba state, Northeastern Brazil.

Toxoplasma gondii and Neospora caninum in slaughtered pigs from Northeast, Brazil

The aims of this study were to evaluate the presence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies, to identify associated risk factors and to isolate T. gondii from slaughtered pigs in Paraíba State, Brazil. A total of 190 pigs from public slaughterhouses were used in the study. An indirect immunofluorescence test was used to detect antibodies, and the isolation of T. gondii was performed with a bioassay in mice based on tissues from seropositive animals. A total of 50 g of brain, heart and tongue tissue from 37 positive pigs with titres ≥ 1:64 was ground, digested with acidic pepsin and inoculated into mice. The prevalence of anti-T. gondii antibodies was 19.5% (95% CI: 14.1%; 25.8%) (37/190), with titres ranging from 1:64 to 1:2048. Viable T. gondii parasites were isolated from 13 of the 37 (35.1%; 95% CI: 20.2%; 52.5%) seropositive pigs. We found that the virulence of the isolates varied; three of these isolates were able to kill all of the inoculated mice. The risk factors for infection were extensive husbandry and feeding with leftovers. The prevalence of antibodies to N. caninum in pigs was 3.2% (95% CI: 1.2%; 6.7%) (6/190), with titres ranging from 1:100 to 1:3200. None of the variables studied were considered to be risk factors for N. caninum. These results show that the prevalence of anti-T. gondii antibodies in swine is high in Paraíba State, that the percentage of viable T. gondii parasites recovered from these animals is also high and that infection by this parasite is closely related to the management of swine. Despite the low prevalence of N. caninum in pigs, further studies are necessary to determine the importance of this parasite for the species.

Coadministration of nematophagous fungi for biological control over gastrointestinal helminths in sheep in the semiarid region of northeastern Brazil.

This study aimed to evaluate coadministration of Duddingtonia flagrans and Monacrosporium thaumasium in a sodium alginate matrix for controlling gastrointestinal helminths in young and adult sheep in the semiarid region of northeastern Brazil. An area of 1ha was divided into two paddocks, in which two experimental groups (fungus and control) were formed, each consisting of six adult females and ten young males. In each group, two subgroups were formed in accordance with the animal category (adult or young). In the fungus group, each animal received 3g of pellets containing 0.6g of fungal mycelium, with 0.3g of D. flagrans and 0.3g of M. thaumasium for each 10 kg of body weight, in their feed twice a week, for six months. In the control group, each animal received 3g of pellets without fungus for each 10 kg of body weight, in their feed twice a week, for six months, serving as a witness group. Reductions in numbers of eggs per gram of feces of 76% among the adult sheep in the fungus group and 83% among the young sheep in the fungus group were observed, in comparison with their respective control subgroups. The groups that received these fungi needed less salvage deworming and presented better packed cell volume percentages, better weight gain and lower levels of L3/kg dry matter in their paddock than the control groups. Thus, it was concluded that coadministration of D. flagrans and M. thaumasium was effective in controlling gastrointestinal helminths of adults and young sheep in the semiarid region of northeastern Brazil.

First report of interaction of nematophagous fungi on Libyostrongylus douglassii (Nematoda: Trichostrongylidae)

Libyostrongylus douglassii is a gastrointestinal nematode parasite of ostriches that can cause up to 50% mortality in young birds. The objective of this study was to compare the predatory capacity of two isolates of the predatory fungi Duddingtonia flagrans (AC001 and CG722 isolates) and one of Arthrobotrys cladodes (CG719) on infective larvae (L3) of L. douglassii under laboratory conditions, in 2% water-agar medium. The results showed that the fungi tested were effective in preying upon the L3 of L. douglassii (P < 0.05), compared with the control group. However, there was no difference in predatory capacity between the fungi tested (P > 0.05) during the seven days of experimental testing. In comparison with the control, without fungus, there were significant decreases (P < 0.05) of 85.2% (AC001), 81.2% (CG722) and 89.2% (CG719) in the average numbers of L3 of L. douglassii recovered from treatments with the isolates tested. In the present study, the three isolates of the predatory fungi D. flagrans (AC001 and CG722) and A. cladodes (CG719) were efficient at in vitro destruction of the L3 of L. douglassii.

Parasites of Psittaciformes and Accipitriformes in Paraíba state, northeastern Brazil

In this study, we investigated the presence of gastrointestinal helminths in 97 captive birds (Psittaciformes and Accipitriformes) necropsied between June and December 2011 in the state of Paraiba, Brazil. Forty-three birds were infected. Psittaciformes were infected by nematode Ascaridia hermaphrodita (97.6%) and cestode Raillietina sp. (2.4%). A. hermaphrodita was found in all species of parrots and Raillietina sp. was found only in Amazona aestiva. A. hermaphrodita was the cause of death, by intestinal obstruction, in 14 of the 40 birds investigated. Accipitriformes were infected by nematode Synhimantus (Synhimantus) rectus (100%) and acantocephalan Centrorhynchus tumidulus (50%). In Brazil, Diopsittaca nobilis and A. aestiva are reported for the first time as hosts of A. hermaphrodita and Raillietina sp., respectively. We concluded that Psittaciformes and Accipitriformes in captivity are affected by nematodes, cestodes and acanthocephalans and that implementation of control measures is essential.

Sheep gastrointestinal helminthiasis in the Sertão region of Paraíba State, Northeastern Brazil: prevalence and risk factors.

In this study, we aimed to establish the prevalence and risk factors relating to gastrointestinal helminthiasis, and to characterize the sanitary management practiced among sheep herds in the Sertão region of the state of Paraíba, northeastern Brazil, based on factors that condition the ways of controlling these parasites in these herds. The research was carried out between April and July 2012. We visited 54 farms, where fecal and blood samples were individually collected from 465 animals. On each farm, a questionnaire was applied to gather information on variables relating to potential risk factors. The prevalence of sheep gastrointestinal helminthiasis in the region was 75.9%. At least one animal tested positive for this helminthiasis on 53 (98.1%) of the 54 farms evaluated. The eggs per gram of feces (EPG) analysis showed the following infection burdens: 51.8% with mild infection, 27.1% moderate infection, 9.9% heavy infection and 11.2% fatal infection. Among the sheep farms visited, anthelmintics were used on 81.5% (p <0.05). The most relevant risk factor in this study was the farm area, because it defines the area available for grazing animals. Properties with many animals and little pasture area, which are the most abundant type in the Sertão region of Paraíba, tend to have high prevalence of gastrointestinal helminthiasis, because the animals are more prone to reinfection. The Sertão region of Paraíba presents high prevalence of gastrointestinal helminthiasis among sheep, and the farm area is the most relevant risk factor for the development of these parasites.

Toxoplasma gondii and Neospora caninum in domestic cats from the Brazilian semi-arid: seroprevalence and risk factors

In the present study we aimed to establish the seroprevalence of T. gondii and N. caninum in stray and domiciled cats from the municipality of Patos, Paraiba state, Brazil. Blood samples were collected from 201 animals: 132 domiciled cats and 69 stray cats. An epidemiological questionnaire was conducted with all cat owners. Indirect immunofluorescent antibody test (IFAT) was performed at cut-offs of 1:16 and 1:50 for T. gondii and N. caninum, respectively. Overall prevalence of seroreagent cats for T. gondii was 43.8%. We found a prevalence of 47.7% in domiciled cats and 36.2% in stray cats. Antibody titers ranged from 1:16 (cut-off) to 1:8192; 1:128 was the most frequent titer. No statistical difference was observed between domiciled cats and stray cats. Correlation was verified between seroreagent for T. gondii and age and hunting habit (P<0.05). No animals tested seroreagent for N. caninum. It was possible to conclude that there is high prevalence of cat seroreagent for T. gondii and that N. caninum is not present in cats from the area studied.

High genetic diversity in Toxoplasma gondii isolates from pigs at slaughterhouses in Paraíba state, northeastern Brazil: Circulation of new genotypes and Brazilian clonal lineages

The consumption of raw or undercooked pig meat containing Toxoplasma gondii cysts is an important transmission route of this protozoon to animals and humans. This study aimed to serologically diagnose, isolate and genotype T. gondii from pigs slaughtered for human consumption in the state of Paraíba, northeastern Brazil. Blood and tissue samples (heart, tongue and brain) were collected from 120 pigs at slaughterhouses in the state of Paraíba. Serological examinations were performed with an indirect immunofluorescent antibody test (IFAT) with a cut-off point of 1:64. Tissues from positive animals were subjected to bioassays in mice to isolate the parasite. A total of 12.5% (15/120) of the animals were positive according to the IFAT, with titres ranging from 64 to 2048. Viable parasites were isolated in 80% (12/15) of the bioassays. The twelve T. gondii isolates obtained in this study and an additional 13 previously described isolates were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using 11 genetic markers. Additionally, microsatellite (MS) analysis was performed using 15 markers. Nineteen of the 25 isolates completely genotyped using PCR-RFLP had 12 different genotypes, six of which were newly identified. One isolate had a mixed infection. The same 18 non-mixed isolates had 16 different genotypes based on the MS analysis. Genotype #13 (Caribbean 1), which is commonly encountered in northeastern Brazil and is probably a clonal lineage circulating in this region, was the most frequent genotype detected through both the PCR-RFLP and MS analyses. These results demonstrate that T. gondii is widespread among pigs slaughtered in the state of Paraíba. The results also confirm that this parasite has high genetic diversity in this region and that non-archetypal genotypes commonly circulate between different hosts and across different regions of Brazil.

Risk factors for Toxoplasma gondii and Neospora caninum seropositivity in buffaloes in Paraiba State, Brazil.

The aims of this survey were to determine the frequency of anti-Toxoplasma gondii and anti-Neospora caninum antibodies and to identify the risk factors associated with seropositivity among buffaloes in the state of Paraíba, Brazil. This survey included 136 buffaloes belonging to 14 herds. To detect anti-T. gondii and anti-N. caninum antibodies, the indirect fluorescent antibody test (IFAT) was used. Among the 136 samples analyzed, 17 (12.5%) were positive for anti-T. gondii antibodies with titers ranging from 64 to 1,024, and 26 (19.1%) for anti-N. caninum with titers from 200 to 1,600. Animals seropositive for both T. gondii and N. caninum were found in 10 of the 14 herds (71.4%). Semi-intensive management systems (odds ratio = 2.99) and presence of pigs (odds ratio = 4.33) were identified as risk factors for T. gondii and N. caninum, respectively. It can be suggested that T. gondii and N. caninum are widespread in buffaloes in Paraíba, and that additional surveys are needed in order to ascertain the importance of these agents for this species and for pigs, and the influence of the farming type on occurrences of seropositive animals.