The ciliated protozoa divide the labor of germline and somatic genetic functions between two distinct nuclei. The development of the somatic (macro-) nucleus from the germinal (micro-) nucleus occurs during sexual reproduction and involves large-scale, genetic reorganization including site-specific chromosome breakage and DNA deletion. This intriguing process has been extensively studied in Tet...

Numerous papers have been published which deal with the occurrence of heavy metals in the various components of freshwater ecosystems (Radwan et al. 1990; Scanferlato and Cairns 1990; Hintelmann et al. 1993) and sewage treatment systems (Yetis and Gokcay 1989; Cimino and Caristi 1990; Dilek and Yetis 1992; Melcer et al. 1992; Moriyama et al. 1992). However, only a few papers refer to the presen...

Sixteen zebu-cross steers, kept under grazing conditions, were supplemented with increasing levels of concentrate (0.4, 0.7 and 1.0% of body weight) over three periods of 41, 41 and 42 days, respectively. The animals were divided into four groups, a control plus groups supplemented with either monensin, yeast culture or a combination of monensin and yeast culture. Samples of rumen contents were...

Despite stringent biosecurity measures, infections by bacterial food pathogens such as Campylobacter are a recurrent problem in industrial poultry houses. As the main transmission route remains unclear, persistence of these infections has been linked to bacterial survival and possibly multiplication within protozoan vectors. To date, however, virtually no information is available on the diversi...

Ruminants have a unique ability to derive energy from the degradation of plant polysaccharides through the activity of the rumen microbiota. Although this process is well studied in vitro, knowledge gaps remain regarding the relative contribution of the microbiota members and enzymes in vivo. The present study used RNA-sequencing to reveal both the expression of genes encoding carbohydrate-acti...