Ultraestructura citohematológica de la trucha arco iris Oncorhynchus mykiss (Salmoniformes: Salmonidae)

• Main Author: Adriana Rodríguez Forero
• Format: Article
• Language: English
• Published: Vicerractoría Investigación 1999-12-01
• Series: Revista de Biología Tropical
• Subjects: Oncorhynchus mykiss; citohematology; ultracitology
• Online Access: http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77441999000400045

Se estudió por ultraestructura la sangre periférica de 5 adultos de una población introducida de trucha arco iris (Oncorhynchus mykiis) cultivados en el Centro de Piscicultura Experimental del Neusa, (73° 38' 28"w; 5° 8'30"N), para describir la morfología de los elementos que la componen. La sangre fue fijada con glutaraldehído, coloreada con tetraóxido de osmio al 1%, deshidratada en gradientes de alcoholes, centrifugada e incluida en resinas. Se observaron eritrocitos, linfocitos, monocitos, leucocitos polimorfonucleares (PMN) y plaquetas. Los eritrocitos mostraron núcleo picnótico y mitocondrias. Se vieron linfocitos de dos tipos: con núcleo redondeado y con núcleo indentado, ambos con ribosomas y acúmulos de 5 a 6 mitocondrias. Los monocitos poseen ribosomas y gránulos agrupados junto con mitocondrias a lo largo del núcleo irregular. Los PMN tienen mitocondrias y numerosos gránulos densos, redondeados y elipsoidales concentrados a lo largo de la ensenada nuclear lobulada. Las plaquetas se vieron ocasionalmente, como células anucleadas, vacuoladas con pequeños gránulos densos, ovalados.<br>Peripheral blood samples from five adult specimens of rainbow trout (Oncorhynchus mykiis) from an introduced population cultured in the Neusa’s Experimental Fish Hatchery (73° 38’28" W; 5° 8’30" N) were studied with the electron microscope. The blood was fixed in 3% buffered glutaraldehyde, followed by 1% buffered osmium tetraoxide, dehydrated in ascending alcohols, and embedded in resines. Cells observed were erythrocytes, lymphocytes, monocytes, polimorphonuclear leucocytes (PMN) and plateletes. Erythrocytes had picnotic nucleus, poliribosomes and mitocondria; lymphocytes were of two types acording to nuclear morphology, one with rounded nucleus and other with indented, notched nucleus. Both had dense cytoplasm without membranes, ribosomes, and mitocondria gathered in clumps of 5 or 6 located in a paranuclear position. Monocytes presented an iregular nucleus and a cytoplasm with ribosomes and granules of variable density, grouped with mitocondria along the concave face of the nucleus. PMN have lobated nucleous, numerous dense granules rounded and elipsoid granules of diferent sizes concentrated towards the notched nucleous, were abundant mitocondria are also present. Platelets were occasionally seen as vacuolated non nucleated cells with small, oval dense granules. The results are similar to those of temperate populations.