Rabbit hepatitis E virus (HEV) has been reported for years and is thought to have the potential for zoonotic transmission from rabbits to humans.  As reported, HEV genotype 3 (gt3) is the most prevalent form of HEV in rabbits.  To determine the prevalence of HEV in commercial rabbit livers, 176 liver samples were collected from an abattoir in Hebei Province, China.  Three (1.7%) samples tested positive for RNA of HEV-ORF2 (open reading frames-2).  Sequence analysis showed that the three isolates shared high identities with each other (94.08–98.85%).  Further analysis showed that all the rabbit strains clustered together in the branch of HEV gt3.  Further study by immunohistochemistry (IHC) assays showed that 131 (74.4%) liver samples were positive for HEV ORF2 protein.  Pathological changes including cell degeneration, inflammatory cell infiltration and bile duct epithelial cell hyperplasia were observed under microscopy.  These findings indicated the presence of HEV in commercial livers of rabbits.  Additional studies should be conducted to investigate the infectivity of rabbit HEV (rHEV) and the potential risks of zoonotic transmission of rHEV from rabbits to human beings.

The assessment of the biomass of energy crops has garnered widespread interest since renewable bioenergy may become a substantial proportion of the future energy supply, and modeling has been widely used for the simulation of energy crops yields.  A literature survey revealed that 23 models have been developed or adapted for simulating the biomass of energy crops, including Miscanthus, switchgrass, maize, poplar, willow, sugarcane, and Eucalyptus camaldulensis.  Three categories (radiation model, water-controlled crop model, and integrated model with biochemical and photosynthesis and respiration approaches) were addressed for the selected models according to different principles or approaches used to simulate biomass production processes.  EPIC, ALMANAC, APSIM, ISAM, MISCANMOD, MISCANFOR, SILVA, DAYCENT, APEX and SWAT are radiation models based on a radiation use efficiency approach (RUE) with few empirical and statistical parameters.  The AquaCrop model is a typical water-crop model that emphasizes crop water use, the expression of canopy cover, and the separation of evapotranspiration to soil evaporation and plant transpiration to drive crop growth.  CANEGRO, 3PG, CropSyst and DSSAT are integrated models that use photosynthesis and respiration approaches.  SECRETS, LPJmL, Agro-BGC, Agro-IBIS, and WIMOVAC/BioCro, DNDC, DRAINMOD-GRASS, and AgTEM are integrated models that use biochemical approaches.  Integrated models are mainly mechanistic models or combined with functional models, which are dynamic with spatial and temporal patterns but with complex parameters and large amounts of input data.  Energy crop models combined with process-based models, such as EPIC in SWAT and CANEGRO in DSSAT, provide good examples that consider the biophysical, socioeconomic, and environmental responses and address the sustainability and socioeconomic goals for energy crops.  The use of models for energy crop productivity is increasing rapidly and encouraging; however, relevant databases, such as climate, land use/land cover, soil, topography, and management databases, are scarce.  Model structure and design assumptions, as well as input parameters and observed data, remain a challenge for model development and validation.  Thus, a comprehensive framework, which includes a high-quality field database and an uncertainty evaluation system, needs to be established for modeling the biomass of energy crops.

Infection by hepatitis B virus (HBV) results in acute and chronic liver damages in humans. Liver products of broilers as a primary food consumed in our daily life have a close connection with public health. The prevalence of the virus in livers and serum of broilers is of great significance, owning to the potential transmission between chickens and humans. Liver tissues and serum samples were tested to investigate the prevalence of hepatitis B virus infection in slaughtered broilers, for expression of HBV antigens and antibodies. The distribution and positive rate of hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg) and hepatitis B e antigen (HBeAg) in liver samples were examined using immunohistochemistry. HBsAg was mainly located in the cytoplasm of hepatocytes with a positivity of 81.61% whereas HBeAg and HBcAg were primarily located in the nucleus of hepatocytes with a positivity of 40.13 and 49.10%, respectively. Enzyme-linked immunosorbent assay (ELISA) analysis of serum for HBV serological markers demonstrated a high prevalence of hepatiits B surface antibody (HBsAb, 54.91%) and hepatitis B core antibody (HBcAb, 27.68%), whereas HBeAb, HBsAg and HBeAg were rarely detectable. Classic hepatitis pathological changes, including swollen hepatocytes, focal parenchymal necrosis, lymphocytic infiltration and hyperplasia of fibrous connective tissues were observed using histopathological analysis. Some of the liver samples were found positive for HBV DNA using nested PCR. Sequence comparison confirmed that all sequences shared 97.5–99.3% identity with human HBV strains. These results demonstrated the existence of HBV in livers and serums of broilers. Animals or animal products contaminated with HBV could raise an important public health concern over food safety and zoonotic risk.