Parasitos gastrintestinais em caprinos no município de Quixadá, Ceará / Gastrointestinal parasites in goats from Quixadá, Ceará

O objetivo desse trabalho foi avaliar a ocorrência dos principais parasitos gastrintestinais que acometem caprinos adultos e jovens do município de Quixadá-Ceará durante a época seca e chuvosa, além de identificar e quantificar as espécies de Eimeria presentes no rebanho. Foram utilizados 654 animais, sendo 334 animais no período seco, dos quais eram 149 matrizes e 185 crias e 320 animais no período chuvoso, sendo 106 matrizes e 214 crias, independente de padrão racial e sistema de criação. As coletas foram realizadas nos meses de novembro e dezembro de 2012 e maio de 2013 no município de Quixadá-Ceará e encaminhadas ao Laboratório de Parasitologia da Embrapa Caprinos e Ovinos na cidade de Sobral-Ceará. Foram coletadas fezes para contagem do número de ovos por gramas de fezes (OPG), contagem de Oocistos por gramas de fezes (OOPG), coprocultura e identificação das espécies de Eimeria com base na morfometria. As matrizes apresentaram maiores médias de ovos do tipo Strongyloidea (372,03) e Strongyloides (8,45) no período seco e no período chuvoso apresentaram maiores médias apenas para Strongyloidea (502,85). O inverso aconteceu com o OOPG, onde as crias apresentaram maiores médias no período seco (9387,41) e no chuvoso (9630,37). O gênero de nematódeo mais frequente na coprocultura foi o Trichostrongylus sp. (63,67%) no período seco e o Haemonchus sp. no chuvoso (66,67%). Em 100% dos rebanhos, foram encontrados oocistos de Eimeria, com 81% dos animais infectados. A ocorrência da eimeriose nas categorias jovens e adultas foi de 64,3% e 83,2% no período seco e de 87,4% e 92,4% no período chuvoso. As espécies identificadas foram: Eimeria alijevi, E. apsheronica, E. arloingi, E. caprina, E. caprovina, E. christenseni, E. hirci, E. jolchijevi e E. ninakohlyakimovae. Nas crias a E. alijevi foi a mais freqüente no período seco e a E. ninakohlyakimovae no chuvoso. Já nas matrizes a espécie E. alijevi apresentou a maior frequência em ambos os períodos. Nos rebanhos estudados foi evidenciado a presença de ovos de nematódeos gastrointestinais e oocistos de Eimeria spp. independente da categoria animal.(AU)

The objective of this study was to evaluate the occurrence of main gastrointestinal parasites and to quantify and identify the species of Eimeria present in young goats and adults in the city of Quixadá, Ceará, during the dry and rainy season. Six hundred fifty-four animals were used, with 334 animals during the dry season, which were 149 mothers and 185 offspring and 320 animals during the rainy season, with 106 mothers and 214 offspring, independent of breed standard and creation system. Samples were collected in the months of November and December 2012 and May 2013 in the city of Quixadá, Ceará and sent to the Parasitology Laboratory of Embrapa Goats and Sheep at Sobral, Ceará, feces were collected for counting the number of eggs per gram of feces (EPG), counting oocysts per gram of feces (OOPG), coproculture and identification of Eimeria species based on the morphometry. Matrices showed higher means egg type Strongyloidea (372.03) and Strongyloides (8.45) in the dry season and the rainy season had higher mean only to Strongyloidea (502.85). The inverse happened to OOPG, where the offspring showed higher means in the dry season (9387.41) and rainy (9630.37). The genus most frequent of nematode in coprocultures was Trichostrongylus. (63.67%) in the dry season and Haemonchus sp. the rainy (66.67%). One hundred percent of the herds, oocysts of Eimeria were found, with 81% of infected animals. The occurrence of eimeriosis in young and adult categories was 64.3% and 83.2% in the dry season and 87.4% and 92.4% during the rainy season. The species identified were: Eimeria alijevi, E. apsheronica, E. arloingi, E. caprina, E. caprovina, E. christenseni, E. hirci, E.and E. jolchijevi ninakohlyakimovae. In the offspring E. alijevi was the most frequent in the dry season and the rainy E. ninakohlyakimovae. Already in matrices the species E. Alijevi showed the highest frequency in both periods. In herds studied it evidenced the presence of gastrointestinal nematodes eggs and oocysts of Eimeria spp. independent of animal category.(AU)

Impaired visual sensitivity within the ipsilesional hemifield following parietal lobe damage.

The parietal cortex is considered to be part of a network of brain areas that modulates competitive interactions between targets and irrelevant distracters in early visual cortex, however there is currently little causal evidence to support this in human observers. It is also unclear as to whether parietal influences on visual perception in humans are limited to the contralesional hemispace or whether a unilateral lesion affects visual sensitivity bilaterally. Here we examined visual sensitivity in two patients with spatial neglect and extinction arising primarily from left-parietal damage. We used a sensitive psychophysical task based on those previously used to demonstrate loss of stimulus selection after lesions to extrastriate cortex. Observers discriminated the orientation of a lateralized suprathreshold target grating that appeared alone or in the context of nearby salient disc distracters. For parietal patients, target sensitivity within both the contralesional and ipsilesional fields was compromised by the presence of distracters. Conversely, healthy matched controls were unaffected by distracters. These results indicate that parietal cortex damage can influence visual perception within both the ipsi- as well as the contralesional field.

Mitochondrial DNA variation of the dog hookworm Ancylostoma caninum in Brazilian populations.

The mitochondrial cytochrome oxidase I gene was partially sequenced for 164 Ancylostoma caninum individuals, originating from five different localities in Brazil, with the aim of describing the genetic diversity and genetic structure of Brazilian hookworm populations. Allelic and nucleotide diversity were moderate (overall h=0.88 and pi=0.016) and were similar among cities. There was moderate genetic differentiation among the populations sampled (approximately Phi(ST)=0.12) and a weak but nonsignificant correlation between geographical and genetic distance. This genetic structure was similar to that observed among populations of the human hookworm, Necator americanus, but distinct from that typically found in trichostrongylid nematode parasites of livestock. Thus, a pattern of different genetic structures among different groups of nematodes is emerging. We also observed a few individuals that had a highly divergent mtDNA sequence (almost 7% sequence divergence from the other sequences). These results in combination with data from other studies suggest that A. caninum populations worldwide consist of a mix of previously differentiated populations, or perhaps even cryptic species. This study contributes to the knowledge of genetic structure and diversity of hookworms, which in turn will be useful in developing methods for their control.

Differential diagnosis of dog hookworms based on PCR-RFLP from the ITS region of their rDNA.

Species of Ancylostoma infecting dogs and sometimes humans are sympatric in many parts of the world. The establishment of a specific molecular diagnostic tool is important, not only to refine information for epidemiological studies, but also to evaluate the efficacy of vaccine programmes and assist in the development of specific drug treatments. The ITS region from 20 specimens of A. braziliense, collected from three separate geographical areas of Brazil, and from 10 specimens of A. caninum, collected from the same area in Brazil were sequenced and analyzed. Alignment of sequences showed that this gene is highly conserved. The intraspecific polymorphism for both species was less then 1%, whereas the interspecific polymorphism was 6.2, 7.3 and 9.4% between A. ceylanicum and A. braziliense; A. caninum and A. ceylanicum and A. ceylanicum and A. braziliense, respectively. Among the three species it was 12.3%. This revealed the ITS region as highly conserved and consequently a good molecular marker for diagnostic studies. In this work, four restriction enzymes were used in a PCR-RFLP using the ITS region of rDNA, to establish a differential diagnosis which discriminates between three Ancylostoma species, A. braziliense, A. caninum and A. ceylanicum. The best pattern was given by the HinfI enzyme, which produced different fragment sizes for each of the three species. Furthermore, the diagnostic tool differentiates DNA extracted directly from faeces of Ancylostoma-infected dogs.

Identification of an expressed gene in Dipylidium caninum.

Recombinant DNA studies have been focused on developing vaccines to different cestodes. But few studies involving Dipylidium caninum molecular biology and genes have been done. Only partial sequences of mitochondrial DNA and ribosomal RNA gene are available in databases. Any molecular work with this parasite, including epidemiology, study of drug-resistant strains, and vaccine development, is hampered by the lack of knowledge of its genome. Thus, the knowledge of specific genes of different developmental stages of D. caninum is crucial to locate potential targets to be used as candidates to develop a vaccine and/or new drugs against this parasite. Here we report, for the first time, the sequencing of a fragment of a D. caninum expressed gene.

Identification of specific male and female genes in adult Ancylostoma caninum.

The hookworm Ancylostoma canium represents a serious health problem, not only for animals but also for humans. These blood-feeding parasites produce various proteolytic enzymes in order to digest the host hemoglobin. The female worm ingests more blood than does the male. It is not known whether this difference is accompanied by expression of sex-specific proteinases. The identification of new genes related either to the developmental process of maturation of each sex or to the proteinases secreted by these worms could provide researchers with new tools to be used in control programs for this important parasite. The differential-display technique was used to compare the gene expression patterns of adult male and female worms in order to find specific genes that could be used as new targets in the control strategies for this parasite.