Structural study of the salivary glands of Anocentor nitens (Acari: Ixodidae) during the feeding cycle.

The salivary glands of Anocentor nitens (Neumann,1897) occur in pairs and are located in the anterolateral region of the general cavity, with milky white color and approximately equal sizes. They consist of a secretory portion and an excretion duct. In some glandular acini, all the cells had a basophilic appearance they were stained by hematoxylin, whereas others presented cells with different staining affinities. In this work, we describe the variations observed in these glands during the feeding cycle of ticks [after feeding (0 h) and successively at 24, 48, 72, 96, 120, and 144 h]. The cells stained by hematoxylin were shown to be more reactive to Alcian blue, thus demonstrating the presence of acid glycosaminoglycans, whereas those stained using eosin presented weak or no reaction. A strong reaction was found by the use of the periodic acid-Schiff (PAS) technique, thereby suggesting the presence of glycogen and/or glycoconjugates containing hexose, confirmed by using salivary amylase before PAS, with partial destaining of the slides. Continuing presence of residual staining in these cells suggests the presence of glycoconjugates containing hexose. Cells with nuclei of circular outline and few granules (of different sizes) were found in type II acini, 72 h after collection. Type I acini presented wide lumina and walls composed of larger numbers of cells of cubic to cylindrical shape. The pronounced degranulation shown in this study over the course of the feeding cycle was associated with the release of substances for oviposition.

Raillietia caprae (Acari: Raillietidae) and Psoroptes ovis (Acari: Psoroptidae) in the ears of goats in the state of Rio de Janeiro, Southeast Brazil.

Ear canals of 145 domestic goats including the breeds Saanen, Toggenburg, Anglobian, Alpine, Moxoto (native) and crossbred goats from 10 smallholder farms were examined by flushing for the presence of ear mites. Prevalence of Raillietia caprae Quintero, Bassols and Acevedo, 1980 was much more higher than Psoroptes ovis (Hering, 1838) in the studied area, respectively 62% (90/145) and 4% (6/145). The youngest animal parasitized was eight months old and the oldest was 10 years old. Subclinical otitis is a common feature of infestation by both species but increase of wax and the presence of pus were detected in the flushed material in approximately 10% of the goats examined.

Histology and ultrastructure of Aedes albopictus larval midgut infected with Bacillus thuringiensis var. israelensis.

Histological and ultrastrucutural alterations in the midgut of Aedes albopictus larvae infected with Bacillus thuringiensis var. israelensis (Bti) were observed by light and transmission electron microscopy (TEM). Two formulations of Bti were used: granulated and powder, with 0.2% active ingredient in 90 larvae of Ae. albopictus distributed in three containers containing 30 larvae each (one control group and two test groups). The midgut epithelium of the control group presented flattened and elongated cells with mace-shape with a narrow base. Midgut epithelium cells' surface was convex and had a large circular nucleus located in the median-apical portion of the cell. These cells also presented a basal lamina with a small accumulation of extracellular fibrous matrix, thus characterizing a basal membrane, with a muscle layer and a peritoneal membrane more externally. After Bti ingestion, the larvae stopped/slowed their natural movements down in 5 min. After 30 min approximately, the swimming movements stopped completely. Internally, the intestinal cells showed a disorganization of the basal processes, dilatation and fragmentation of the rough endoplasmic reticulum, with intense cytoplasmic vacuolization. There were concentric dense laminas accumulated in the cytoplasm, and these residual membranous bodies were seen greatly increased in size after 60 min. Mitochondria, fragments of rough endoplasmic reticulum and other remainder organelles were surrounded and segregated from the cytoplasm by exocytosis. This article reports the histopathological alterations in the midgut of Ae. albopictus after infection with Bti and contributes to a better understanding of the mode of action of this bacterial strain used as bioinsecticide against mosquito larvae.

Raillietia caprae (Acari: Raillietidae) and Psoroptes ovis (Acari: Psoroptidae) in the ears of goats in the state of Rio de Janeiro, Southeast Brazil / Raillietia caprae (Acari: Raillietidae) e Psoroptes ovis (Acari: Psoroptidae) nos condutos auditivos de caprinos no Estado do Rio de Janeiro, Brasil

Ear cannals of 145 domestic goats including the breeds Saanen, Toggenburg, Anglobian, Alpine, Moxoto (native) and crossbred goats from 10 smallholder farms were examined by flushing for the presence of ear mites. Prevalence of Raillietia caprae Quintero, Bassols and Acevedo, 1980 was much more higher than Psoroptes ovis (Hering, 1838) in the studied area, respectively 62 percent ( 90/145) and 4 percent ( 6/145). The youngest animal parasitized was eight months old and the oldest was 10 years old. Subclinical otitis is a common feature of infestation by both species but increase of wax and the presence of pus were detected in the flushed material in approximately 10 percent of the goats examined.

Os condutos auditivos de 145 caprinos das raças Saanen, Toggenburg, Anglobian, Alpine, Moxoto (native) e mestiços provenientes de 10 pequenos criadores foram examinados pela técnica de lavagem para diagnosticar a infestação por ácaros. A prevalência de Raillietia caprae Quintero, Bassols and Acevedo, 1980 foi muito mais alta do que Psoroptes ovis (Hering, 1838) - 62 por cento (90/145) e 4 por cento (6/145), respectivamente. O animal parasitado mais jovem tinha oito meses de idade e o mais velho 10 anos. Otite subclínica é comum nas infestações por ambas espécies mas aumento de cerume e presença de pus foram diagnosticados no material da lavagem em aproximadamente 10 por cento dos caprinos examinados.