Identification of Plant Soot as Novel Safe Feed Additive: Evaluation of 90-Day Oral Toxicity and Prenatal Developmental Toxicity in Rats.

Plant soot, as a novel feed additive, could not only improve digestive function but also adsorb mycotoxins and inhibit bacterial infections. The subchronic toxicity and prenatal developmental effects of plant soot were studied for the first time. Our results indicated that there was no subchronic toxicity in the range of 2,000-50,000 mg/kg plant soot added in the feed, and there was no significant difference in reproductive function, embryo development, and teratogenicity between the pregnant rats exposed to 312.5, 1,250, and 5,000 mg/kg plant soot and the control group. The maximum no-observed effect level (NOEL) of supplemental dosage in feed could be set to 50,000 mg/kg, and the maximum intragastric NOEL could be set to 5,000 mg/kg, which preliminarily provided guidance on daily additive amount or clinical protocols for plant soot, as well as promoting the development and application of this harmless antibiotic substitutes.

Effects of Activated Charcoal-Herb Extractum Complex on Antioxidant Status, Lipid Metabolites and Safety of Excess Supplementation in Weaned Piglets.

This study was aimed at evaluating the effects of activated charcoal-herb extractum complex (CHC) on antioxidant status, serum lipid metabolites and its safety supplement in weaning piglets. In experiment 1, a total of 216 piglets (Duroc × Landrace × Large White) weaned at 28 days of age with initial body weight of 8.55 ± 1.18 kg were assigned randomly to six treatment groups. each treatment group had six pens, with six pigs per pen. Pigs were fed a corn-soybean meal-based diet supplemented with 500, 1000, 1500 or 2000 mg kg-1 of CHC over two 14-d periods. Diets supplemented with 0 and 1000 mg kg-1 of montmorillonite (MMT) were set as the negative and positive controls, respectively. In experiment 2, pigs (n = 108) weaned at 28 days of age with initial body weight of 8.58 ± 0.04 kg were randomly assigned to three treatment groups. Each treatment group had six pens, with six pigs per pen. Pigs were fed a corn-soybean meal-based diet supplemented with 0, 1000 or 10,000 mg kg-1 of CHC over two 14-d periods. In experiment 1, on day 14, supplementation with CHC significantly decreased very low-density lipoprotein (VLDL) concentration while they decreased low-density lipoprotein (LDL) concentration on d 28, CHC at 500, 1000 or 1500 mg kg-1 significantly increase high-density lipoprotein (HDL) concentration. Supplementation with 500 or 1000 mg kg-1 CHC reduced serum malondialdehyde (MDA) concentration during the entire experimental period and increased the concentration of serum total superoxide dismutase (T-SOD) on d 14. CHC at 500 or 1000 mg kg-1 significantly reduced the liver MDA concentration and increased liver T-SOD concentration. In experiment 2, increased ADG was obvious during the first 14 days and the whole period in 1000 mg kg-1 supplemented pigs, similarly F: G was lowest in the first 14 days. There was no difference in growth performance, visceral index, haematological and serum biochemical parameters and visceral organs morphology between pigs fed 10,000 mg kg-1 of CHC and control. Together, 500 to 1000 mg kg-1 CHC was confirmed to improve antioxidant status, and serum lipid metabolites in this study and excess supplementation of CHC is safe in weaning piglets.

Effects of activated charcoal-herb extractum complex on the growth performance, immunological indices, intestinal morphology and microflora in weaning piglets.

This study was conducted to evaluate the effects of activated charcoal-herb extractum complex (CHC) on the growth performance, immunological indices, intestinal morphology and microflora in weaning piglets to determine the optimal supplemental dose. A total of 216 weaned piglets (Duroc × Landrace × Large White) with an initial body weight of 8.55 ± 1.18 kg were randomly assigned to six treatment groups; each treatment group had six pens, with six pigs per pen. The study period was 28 d. Pigs were fed a corn-soybean meal-based diet supplemented with 500, 1000, 1500 or 2000 mg kg-1 of CHC over two 14-d periods. Two additional diets containing 0 and 1000 mg kg-1 of montmorillonite were set as the negative and positive controls, respectively. Supplementation with 500 mg kg-1 of CHC significantly increased average daily gain compared with the positive and negative controls during phase I and the entire experimental period (P < 0.05). During phase I, 500 and 1000 mg kg-1 of CHC significantly decreased diarrhea incidence compared with the negative control, and increased serum IGF-1 and serum IgM levels compared with the controls (P < 0.05). CHC at 500 mg kg-1 significantly decreased the diarrhea score during the entire experimental period compared with the negative control (P < 0.05). On day 28, supplementation with 500 and 1000 mg kg-1 of CHC increased serum IgG, IL-1ß, and duodenum and jejunum secretory IgA compared with the negative control and decreased duodenum and jejunum MDA levels compared with the controls (P < 0.05). Increased duodenum and jejunum villus height and an increased ratio of villus height to crypt depth were observed compared with the negative control and decreased viable counts of E. coli in the cecum were detected compared with the controls (P < 0.05). Collectively, the optimal dose of CHC was found to be 500 to 1000 mg kg-1 in this study.