This study investigated the effects of dietary supplementation with 4 types of oligosaccharides on the growth performance, concentrations of the major odor-causing compounds in excreta and cecal microflora of broilers. Three hundred 21-day-old Archer Abor broilers with an average initial live weight of 702.3 g were randomly divided into 5 dietary treatments: basal diet, basal diet + 5 g/kg of mannan-oligosaccharide (MOS), basal diet + 1.2 g/kg of inulin, basal diet + 1.5 g/kg of fructo-oligosaccharide (FOS), and basal diet +1.25 g/kg of soybean oligosaccharide (SBOS), respectively. Each diet was fed to 6 replicates of 10 birds from d 21 to 42, and body weight and feed intake were recorded. Fresh excreta were sampled from each replicate on d 40, 41, and 42 and stored at -20 °C until further analysis. On d 42, the ceca of killed birds were aseptically removed, and the cecal contents were collected into sterile containers and stored at -80 °C until further analysis. Results showed that feeding inulin, FOS, and SBOS diets resulted in an improvement in daily gain (P < 0.05). Broilers fed the SBOS diet showed lower feed:gain ratio (1.84g:g) than the other groups (P > 0.05). Broilers fed the FOS diet showed the lowest volatile basic nitrogen, pH value, and indole and skatole contents in excreta, and broilers fed the SBOS diet had higher total volatile fatty acids concentrations than control (P < 0.05). The cecal microbial community was measured using the PCR-DGGE, which indicated that the cecal microflora Shannon-wiener index and richness of SBOS-fed broilers were significantly higher than that of the control (P < 0.05). The lowest evenness was recorded in the FOS group, which was significantly lower than the other groups (P < 0.05) except the SBOS group. Based on the sequences of the corresponding 16S rDNA of the DGGE bands, in combination with the contents of the major odor-causing compounds in excreta, it is suggested that uncultured Lachnospiraceae bacterium and Bacteroides sp. were associated with the production of major odor-causing compounds in excreta.

The experiment was conducted to investigate the in vitro effects of inulin and soya bean oligosaccharide (SBO) on the metabolism of L-tryptophan (L-try) to skatole production, and the intestinal microbiota in broilers. Treatments were as follows: caecal microbiota control (Cc), Cc + inulin, Cc + SBO, rectal microbiota control (Rc), Rc + inulin and Rc + SBO. Microbial suspensions were anaerobically incubated at 38°C for 24 hr. The results showed that concentrations of skatole and acetic acid were significantly lower in caecal microbiota fermentation broth (MFB) than those in rectal MFB (p < .05). Addition of inulin or SBO significantly decreased the concentrations of indole and skatole and rate of L-try degradation (p < .05). Inulin groups had lower indole than SBO groups (p < .05). PCR-DGGE analysis revealed that addition of inulin or SBO decreased the microbiota richness (p < .05), but no significant differences in Shannon index (p > .05). Four distinct bands were detected in inulin and SBO groups, which were related to two of Bacteroides, one of Firmicutes and Bifidobacteria. Six bands were detected only in control groups, which represented uncultured Rikenellaceae, Roseburia, Escherichia/Shigella dysenteriae, Bacteroides uniformis (T), Parabacteroides distasonis and Enterobacter aerogenes. Populations of Lactobacilli, Bifidobacteria and total bacteria in inulin groups were higher than those in control groups (p < .05). For SBO groups, only population of total bacteria increased (p < .05). However, there were no significant differences in Escherichia coli population among treatments (p > .05). These results suggest that reduced concentrations of skatole and indole in the presence of inulin and SBO may be caused by decrease in L-try degradation rate, which were caused by change in microbial ecosystem and pH value. Uncultured B. uniformis (T) and E. aerogenes may be responsible for degradation of L-try to skatole.

Tibetan chickens have good adaptation to hypoxic conditions, which can be reflected by higher hatchability than lowland breeds when incubated at high altitude. The objective of this trial was to study changes in egg composition and metabolism with regards the adaptation of Tibetan chickens to high altitude. We measured the dry weight of chicken embryos, egg yolk, and egg albumen, and the activity of lactate dehydrogenase (LDH) and succinic dehydrogenase (SDH) in breast muscle, heart, and liver from embryos of Tibetan chicken and Dwarf chicken (lowland breed) incubated at high (2,900 m) and low (100 m) altitude. We found that growth of chicken embryos was restricted at high altitude, especially for Dwarf chicken embryos. In Tibetan chicken, the egg weight was lighter, but the dry weight of egg yolk was heavier than that of Dwarf chicken. The LDH activities of the three tissues from the high altitude groups were respectively higher than those of the lowland groups from d 15 to hatching, except for breast muscle of Tibetan chicken embryos on d 15. In addition, under the high altitude environment, the heart tissue from Tibetan chicken had lower LDH activity than that from Dwarf chicken at d 15 and 18. The lactic acid content of blood from Tibetan chicken embryos was lower than that of Dwarf chicken at d 12 and 15 of incubation at high altitude. There was no difference in SDH activity in the three tissues between the high altitude groups and the lowland groups except in three tissues of hatchlings and at d 15 of incubation in breast muscle, nor between the two breeds at high altitude except in the heart of hatchlings. Consequently, the adaptation of Tibetan chicken to high altitude may be associated with higher quantities of yolk in the egg and a low metabolic oxygen demand in tissue, which illuminate the reasons that the Tibetan chicken have higher hatchability with lower oxygen transport ability.

The experiment was conducted to investigate the influence of different levels of zinc (Zn) on cashmere growth, plasma testosterone and Zn profile in male Cashmere goats. Twenty-eight male Liaoning Cashmere goats, 3 years old and body weight at 56.2 ± 2.45 kg, were assigned to four groups. The animals were fed a basal diet containing of 45.9 mg Zn/kg dry matter (DM) basis and supplemented with 0, 20, 40 or 80 mg Zn (reagent grade ZnSO₄ ·7H₂ O) per kg DM for 90 days. There was no significant effect on growth and diameter of cashmere fibre for Zn supplemented in diets. However, the length and growth rate of wool were improved (p < 0.05) with dietary Zn. The length and growth rate of wool were higher (p < 0.05) for the groups supplemented with 40 or 80 mg Zn/kg DM compared with that of 20 mg Zn/kg DM treatment group. Plasma testosterone concentration was increased for Zn supplemented in diets, and the testosterone concentration was higher (p < 0.05) in goats fed on the diet supplemented with 40 or 80 mg Zn/kg DM compared with those fed on basal diet. Plasma Zn concentrations increased (p < 0.05) with increasing dietary Zn and supplemented with 40 and 80 mg Zn/kg DM groups improved plasma Zn concentration (p < 0.05) more than 20 mg Zn/kg DM group. Fibre Zn content was higher (p < 0.05) in groups supplemented with 40 or 80 mg Zn/kg DM compared with control group, but no difference between Zn-supplemented groups (p > 0.05). The activity of plasma alkaline phosphatase was increased (p < 0.05) due to dietary Zn supplementation; however, no difference was found between supplemented treatment groups (p > 0.05). In conclusion, Zn content (45.9 mg Zn/kg DM) in control diet was insufficient for optimal wool growth performance, and we recommended the level of dietary Zn for such goats is 86 mg/kg DM during the breeding season and cashmere fibre growing period.