Em 10c transmission electron microscope

A sudden onset of illness was observed in four newborn Limousin calves, which were housed in the same pen as their mothers on a farm in northern Germany. The animals ranged from one to sixteen days of age. The calves showed apathy, dehydration, and polydipsia and the three youngest animals died within twelve hours of onset of symptoms. The oldest calf had a protracted disease course with overt diarrhea but survived and recovered completely following symptomatic therapy. One of the younger calves (eight days old) died during transport to a veterinary clinic and was submitted for necropsy. Samples derived from various organs were collected, formalin fixed, stained with hematoxylin–eosin, and sectioned as previously described [21 (link)]. Samples for transmissible electron microscopy (TEM) were also processed by the pop off technique [22 (link)] and visualization was performed using an EM 10C transmission electron microscope (Carl Zeiss). Tissues were routinely tested for notifiable bacterial and viral pathogens (Additional file 1).

Infected cultures were rinsed in PBS five times to remove nonadhered S. pneumoniae and immediately fixed in 2.5% (v/v) glutaraldehyde in 0.1 M sodium cacodylate buffer pH 7.2 at 4 °C for 1 h. Cells were scraped out of the dishes on ice, centrifuged at 900 × g for 10 min, and post-fixed in 1% osmium tetroxide (Sigma) in 0.1 M sodium cacodylate buffer containing 3.5% sucrose at 4 °C for 30 min. Cells were then washed in the same buffer, dehydrated in acetone, and embedded in PolyBed 812 (Polyscience, Philadelphia, PA, USA). Thin sections were obtained in an OmU3 Reichert ultramicrotome, stained with aqueous 2% uranyl acetate, and examined in a Zeiss EM 10C transmission electron microscope.