Chinese herbs have been used as feed additives in animal production. This study investigated the effects of a Chinese herbal feed-additive (TCM, which contained Elsholtzia ciliate, Atractylodes macrocephala, Punica granatum pericarpium, and Cyperus rotundus) on the production performance, egg quality, antioxidant capacity, immunity, and intestinal health of Roman laying hens. A total of 720 28-week-old hens were randomly allotted to three groups with six replicates of forty hens each. The groups were fed a basal diet (CON group), a basal diet with 50 mg/kg zinc bacitracin (ABX group), or a basal diet with 400 mg/kg TCM (TCM group) for 56 days. The results showed that the TCM group increased egg production, egg mass, albumen height, and Haugh unit compared with the CON group (p < 0.05). There were no significant differences in egg weight, feed intake, feed conversion rate, and eggshell strength among all three groups (p > 0.05). Compared with the CON group, the TCM group enhanced the activities of glutathione peroxidase, total antioxidant capacity, and superoxide dismutase in serum and liver, and reduced malondialdehyde content (p < 0.05). The TCM also increased the levels of interleukin-2, interferon-γ, immunoglobulin A, immunoglobulin M, and immunoglobulin G, and decreased the levels of interleukin-6 and interleukin-8 compared with the CON group (p < 0.05). Furthermore, the TCM group increased jejunal goblet cell density and decreased ileal crypt depth and lymphocyte density compared with the CON group (p < 0.05). The results of 16S rRNA demonstrated that the TCM can change the diversity and composition of intestinal microbiota. At the phylum level, the abundance of Bacteroides increased while that of Firmicutes decreased in the TCM group (p > 0.05). At the genus level, the abundance of Lactobacillus, Rikenellaceae_RC9_gut_group, and Phascolarctobacterium increased while that of Bacteroides and unclassified_o__Bacteroidales decreased in the TCM group (p > 0.05). The effects of ABX were weaker than those of the TCM. In conclusion, the TCM has positive effects on production performance and the intestinal health of hens.

Coccidiosis is a prevalent problem in chicken production. Dietary addition of coccidiostats and vaccination are two approaches used to suppress coccidia in the practical production. Methionine (Met) is usually the first limiting amino acid that plays important roles in protein metabolism and immune functions in chickens. The present study is aimed to investigate whether increasing dietary Met levels will improve the anticoccidial effects in broilers medicated or vaccinated against coccidia under Eimeria (E.) tenella-challenged condition. Two thousand male Partridge Shank broiler chicks were obtained from a hatchery. After hatch, birds were weighed, color-marked and allocated equally into two anticoccidial treatments, namely medicated and vaccinated groups. Chicks were either fed, from 1 d of age, diets containing coccidiostat (narasin) or diets without the coccidiostat but were inoculated with an anticoccidial vaccine at 3 d of age. At 22 d of age, 1080 chicks among them were randomly allocated evenly into 6 groups under a 2 × 3 treatment with 2 anticoccidial programs and 3 dietary methionine (Met) levels. Chicks medicated or vaccinated against coccidia were fed diets containing 0.45%, 0.56% or 0.68% of Met from 22 to 42 d of age. All chicks were orally introduced with an amount of 5 × 104 sporulated oocysts of E. tenella at 24 d of age. The growth performance, serum anti-oxidative indexes, intestinal morphology, cecal lesion scores, fecal oocyst counts and immune parameters were measured. The results showed increasing dietary Met level from 0.45% to 0.56% and 0.68% improved weight gain and feed conversion of broilers medicated against coccidia. In contrast, higher dietary levels of Met did not improve growth performance of the vaccinated chickens. Higher Met levels helped the medicated chickens resist E. tenella infection, as indicated by improved intestinal morphology and immune functions as well as decreased cecal lesion and fecal oocyst counts. Anticoccidial vaccination is a better strategy for controlling coccidiosis than feeding narasin, due to not only greater growth performance, but also the lower Met supplementation. Furthermore, higher dietary Met levels improved growth performance of chickens medicated rather than vaccinated against coccidia under E. tenella-challenged condition.

SUMMARY. This study was conducted to investigate the effects of grape seed extract (GSE) and yeast culture (YC) on average daily feed intake (ADFI), feed/egg r

This study was conducted to evaluate the influence of supplementing tea polyphenols (TP) in diet of laying hens on yolk cholesterol content and production performance. A total of 1800 Lohmann laying hens aged 48 weeks were randomly allocated to 6 groups. Each group consisted of 6 replicates with 50 layers. The feeding experiment was 4 weeks including one-week acclimatization. Layers fed basal diet supplemented with 0, 150, 200, 250, 300 and 350 mg TP/kg diet, respectively. The results showed that average daily feed intake (ADFI), feed conversion ratio (FCR), average egg weight (AEW), laying rate and the indicators of egg quality were not significantly affected by the diet supplemented with 300 mg/kg TP (p>0.05). However, yolk cholesterol content decreased by increasing TP concentration (p<0.01), with 18.06% reduction in layers fed diet supplemented with 300 mg TP/kg. Also, the diet supplemented with 300 mg/kg TP significantly decreased plasma triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) level (p<0.05). The activity of serum glutathione peroxidase (GSH-Px) was enhanced by increasing TP concentration, while the content of serum methane dicarboxylic aldehyde (MDA) was decreased by increasing TP concentration. The highest activity of GSH-Px and the lowest serum MDA content were both determined in 300 mg/kg TP group (p<0.01). In conclusion, this study suggests that the addition of 300 mg TP/kg basal diet had no negative effect on the production performance laying hens, yet decreased the egg yolk cholesterol content and enhanced the antioxidant capacity of laying hens at the same time.