Comparative Analysis on the Duodenal Microbiota Community in Geese Fed with the All-grass or Basal Diet

Geese (Anser cygnoides) possess stronger ability of roughage digestion and utilization than other poultries, hence, it has become the focus of attention of scientists. Duodenal, jejunum and ileum were mainly participated in food digestion and nutrient absorption, while the cecum was responsible for biological fermentation. Effects on the geese's cecal microbiota community by feeding with the all-grass diet have been investigated, however, whether it had an influence on the geese's duodenal microbiota community remains unexplored. To address this problem, geese feeding with the basal diet for 28 days (G1), the basal diet for 28 days and the all-grass diet for the following 14 days (G2), the basal diet for 42 days (G3) were selected, respectively. The duodenal segments of geese were collected and the hypervariable V3-V4 region of the bacterial 16S rRNA gene was sequencing. A total of 4 main phyla and 16 main genera were identified. Moreover, we also successfully identified that two taxa including the Helcococcus and Clostridium could be used as distinguishing biomarkers specific to G2. The functional profiles of the duodenum microbiota were mainly involved in the membrane transport (e.g. ABC transporters), amino acid metabolism, energy metabolism, metabolism of cofactors and vitamins, and cellular processes and signaling pathways in geese feeding with the all-grass diet. In conclusion, the all-grass diet could impact the composition of duodenal microbiota. However, to resolve the underlying mechanism of the fiber digesting and utilization in geese's gut microbiota, the whole intestinal system needs to be assessed by further studies.(AU)

The effects of threonine on performance parameters, carcass traits, visceral organ indices and serum biochemical parameters of Linwu ducks, aged 4 to 8 weeks

This study was conducted to establish dietary threonine (Thr) levels for Linwu ducks, aged 4 to 8 wk. Experimental diets formulated to contain 0.56, 0.61, 0.66, 0.71, 0.76, and 0.81% Thr fed to Linwu ducks. A total of 360 healthy Linwu female ducks with similar body weight (1183.89±3.83 g) were randomly divided into six groups, with five replicates in each group, and 12 ducks in each replicate. Samples were collected at 8 wk for the determination of growth performance, carcass traits, visceral organ indices, and serum biochemical parameters. As a result of this study, Thr level had no significant influence on the final weight, the daily gain, feed/gain ratio, and average daily intake (p>0.05). Similarly, there were no significant effects of dietary Thr on carcass traits and visceral organ indices (p>0.05). The pancreatic index was highest among all the treatments when the dietary Thr level was 0.66%. The different dietary Thr levels had no significant effect (p>0.05) on the concentration of total protein (TP), triglyceride (TG), total cholesterol (TC), glucose (GLU), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and glutathione (GSH). However, the serum MDA concentration in the 0.66% treatment was lower (P=0.068) than in the other treatments. In conclusion, Thr at 0.66% concentration may have an antioxidant activity and exert positive effect on Linwu ducks.(AU)

The effects of threonine on performance parameters, carcass traits, visceral organ indices and serum biochemical parameters of Linwu ducks, aged 4 to 8 weeks

This study was conducted to establish dietary threonine (Thr) levels for Linwu ducks, aged 4 to 8 wk. Experimental diets formulated to contain 0.56, 0.61, 0.66, 0.71, 0.76, and 0.81% Thr fed to Linwu ducks. A total of 360 healthy Linwu female ducks with similar body weight (1183.89±3.83 g) were randomly divided into six groups, with five replicates in each group, and 12 ducks in each replicate. Samples were collected at 8 wk for the determination of growth performance, carcass traits, visceral organ indices, and serum biochemical parameters. As a result of this study, Thr level had no significant influence on the final weight, the daily gain, feed/gain ratio, and average daily intake (p>0.05). Similarly, there were no significant effects of dietary Thr on carcass traits and visceral organ indices (p>0.05). The pancreatic index was highest among all the treatments when the dietary Thr level was 0.66%. The different dietary Thr levels had no significant effect (p>0.05) on the concentration of total protein (TP), triglyceride (TG), total cholesterol (TC), glucose (GLU), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and glutathione (GSH). However, the serum MDA concentration in the 0.66% treatment was lower (P=0.068) than in the other treatments. In conclusion, Thr at 0.66% concentration may have an antioxidant activity and exert positive effect on Linwu ducks.

Bioavailability comparison of free and esterified lutein for layer hens

Lutein supplements are often used to pigment and enrich layer chicken eggs. This experiment was conduced to compare the bioavailability of free and esterified lutein, by depletion method. Forty chickens were randomly divided into two groups. After 2 weeks of washout period, when all birds were fed the same low lutein basal diet, the two groups were fed for another 2 weeks with diets supplemented with free lutein or esterified lutein. Two experimental diets were supplemented with the same amount of 15 mg lutein/kg. On day 0 (baseline) and days 3, 7, and 14, birds fasting morning plasma samples were collected and stored for lutein analysis by high performance liquid chromatography method (HPLC). Results showed that: 1) Plasma lutein concentration increased dramatically after feeding free or esterified lutein; 2) Plasma lutein level in birds fed the diet supplemented with free lutein significantly differed from those fed esterified lutein on day 3. 3) There were no significant differences in plasma lutein levels between free lutein and esterified lutein on days 7 and 14. In conclusion, the lutein bioavailability from free lutein or esterified lutein supplements was comparable.

Bioavailability comparison of free and esterified lutein for layer hens

Lutein supplements are often used to pigment and enrich layer chicken eggs. This experiment was conduced to compare the bioavailability of free and esterified lutein, by depletion method. Forty chickens were randomly divided into two groups. After 2 weeks of washout period, when all birds were fed the same low lutein basal diet, the two groups were fed for another 2 weeks with diets supplemented with free lutein or esterified lutein. Two experimental diets were supplemented with the same amount of 15 mg lutein/kg. On day 0 (baseline) and days 3, 7, and 14, birds fasting morning plasma samples were collected and stored for lutein analysis by high performance liquid chromatography method (HPLC). Results showed that: 1) Plasma lutein concentration increased dramatically after feeding free or esterified lutein; 2) Plasma lutein level in birds fed the diet supplemented with free lutein significantly differed from those fed esterified lutein on day 3. 3) There were no significant differences in plasma lutein levels between free lutein and esterified lutein on days 7 and 14. In conclusion, the lutein bioavailability from free lutein or esterified lutein supplements was comparable.