The breakdown of soil aggregates under rainfall and their abrasion in overland flow are important processes in water erosion due to the production of more fine and transportable particles and, the subsequent significant effect on the erosion intensity.  Currently, little is known about the effects of sediment load on the soil aggregate abrasion and the relationship of this abrasion with some related hydraulic parameters.  Here, the potential effects of sediment load on soil aggregate abrasion and hydraulic parameters in overland flow were investigated through a series of experiments in a 3.8-m-long hydraulic flume at the slope gradients of 8.7 and 26.8%, unit flow discharges from 2×10^–3 to 6×10^–3 m² s⁻¹, and the sediment concentration from 0 to 110 kg m^–3.  All the aggregates from Ultisols developed Quaternary red clay, Central China.  The results indicated that discharge had the most significant (P<0.01) effect on the aggregates abrasion with the contributions of 58.76 and 60.34%, followed by sediment feed rate, with contributions of 39.66 and 34.12% at the slope gradients of 8.7 and 26.8%, respectively.  The abrasion degree of aggregates was found to increase as a power function of the sediment concentration.  Meanwhile, the flow depth, friction factor, and shear stress increased as a power function along with the increase of sediment concentration at different slope gradients and discharges.  Reynolds number was obviously affected by sediment concentration and it decreased as sediment concentration increased.  The ratio of the residual weight to the initial weight of soil aggregates (Wr/Wi) was found to increase as the linear function with an increasing flow depth (P=0.008) or Reynolds number (P=0.002) in the sediment-laden flow.  The Wr/Wi values followed a power function decrease with increasing friction factor or shear stress in the sediment-laden flow, indicating that friction factor is the best hydraulic parameter for prediction of soil aggregate abrasion under different sediment load conditions.  The information regarding the soil aggregate abrasion under various sediment load conditions can facilitate soil process-based erosion modeling.

Recently, saccharicterpenin extracted from Camellia oleifera seed meal has become a widely used feed supplement in animal husbandry.  In order to assess its safety, this study was designed to investigate the toxicity and histopathological effects of saccharicterpenin on piglets.  One hundred-fifty weaned pigs ((Yorkshire×Landrace)×Duroc), 75 males and 75 females with body weight (BW) of (7.35±0.29) kg, were randomly allotted to groups receiving diets supplemented with 0, 500, 1 000, 2 500 or 5 000 mg kg^–1 saccharicterpenin for 70 d.  The diet with 500 mg kg^–1 saccharicterpenin supplementation improved liver glutathione peroxidase (GSH-Px) activity, and the diet with 1 000 mg kg^–1 saccharicterpenin supplementation improved liver glutathione S-transferase (GSH-S) activity in piglets on d 70 (P<0.05).  At 2 500 mg kg^–1, saccharicterpenin in the diets reduced average daily feed intake (ADFI) and average daily gain (ADG) of piglets from d 1 to 35, damaged the cardiac tissue and liver on d 35, and decreased white blood cell counts (WBC), activities of catalase (CAT) and GSH-Px, and concentrations of glucose (GLU) and urea nitrogen (BUN) in the blood of piglets on d 70 (P<0.05).  In addition, diets with 5 000 mg kg^–1 saccharicterpenin supplementation reduced ADFI, ADG and increased diarrhea rates of piglets from d 36 to 70, and decreased hemoglobin (HGB) concentration and activity of CAT in the blood of piglets on d 70 (P<0.05).  Moreover, at a rate of 5 000 mg kg^–1, saccharicterpenin supplementation increased pancreas index on d 35 and hepatic index on d 70, and damaged cardiac tissue, liver and spleen during the whole experimental period (P<0.05).  These results suggested that dietary 500 mg kg^–1 saccharicterpenin supplementation had beneficial effects on piglets, but excessive supplementation
(2 500 or 5 000 mg kg^–1) of saccharicterpenin in the diets could lead to growth retardation, hematological abnormalities and organ injuries.

The present study was conducted to evaluate the effect of dietary mulberry (Morus alba L.) leaves powder (MLP) supplementation on meat quality of finishing pigs.  A total of 40 Duroc×Landrace×Yorkshire pigs (initial body weight of (40.5±0.63) kg) were randomly allotted into two treatments, fed either with control diet or 15% MLP diet for 85 d.  The results showed that MLP diet decreased (P≤0.05) average daily gain (ADG) and increased (P<0.05) feed/gain ratio (F/G) in the finishing and whole period.  MLP diet also decreased (P<0.05) carcass weight, dressing percentage, last rib and average backfat depth.  However, MLP diet increased (P<0.05) intramuscular fat (IMF) content, decreased (P<0.05) shear force, cooking loss and drip loss.  In addition, MLP diet increased (P<0.05) total antioxidative capacity, glutathione peroxidase and tended (P<0.10) to increase total superoxide dismutase in serum.  In longissimus thoracis, myosin heavy chain (MyHC) I and IIa mRNA levels were increased (P≤0.05) for MLP diet.  In conclusion, 15% MLP supplementation reduced the growth performance and carcass traits, but improved meat quality of finishing pigs possibly through the change of myofiber characteristics, enhancement of antioxidative capacity and increase of IMF.