Spermatogenesis,sperm cell morphology and accompanying secretions from two interstitial marine mites

The sperm cell morphology and spermatogenesis of Halacaroides antoniazziae Pepato Tiago and da Rocha 2011 and Acaromantis vespucioi Pepato and Tiago 2004 was investigated. Halacaroides sperm cells have a complete acrosomal complex, dense tubules crossing the cytoplasm and modified mitochondria. Mature sperm cells are surrounded by two kinds of secretions. Inside the ejaculatory duct, they lie upon a centre composed of a secretion structured as heaps of elongated bodies. Acaromantis spermatozoa are spindle shaped and lack an acrosomal complex. The plasmalemma is deeply folded; the cytoplasm is very reduced and devoid of organelles. A single kind of globular secretion was found. The sperm mass is surrounded by two layers of amorphous secretions. These species share a peripheral pattern of nuclear condensation during spermatogenesis, a possible apomorphy for most halacarids, and no special adaptation to the interstitial environment could be related to their sperm cell morphology.     

Carcinomas of the liver in Osborne-Mendel rats ingesting methoxychlor.

Osborne-Mendel female and male rats ingested 0, 10, 25, 100, 200, 500, or 2000 ppm technical methoxychlor for periods up to two years. Male and female rats developed significant incidences of hepatocellular carcinomas of the liver. The carcinomas varied from well differentiated to undifferentiated. Carcinomas of the ovary were also significantly increased in treated female rats.