Objective This study investigated the effects of 1,3-1,6 beta-glucan added to the diet of Haidong chicks reared under hypoxic conditions, to ascertain the growth performances, immunity and intestinal morphology changes. Methods A total of 750 chicks were divided into five groups and fed diets containing 0.5 g/kg, 1.0 g/kg, and 2.0 g/kg 1,3-1,6 beta-glucan from yeast (G1, G2, G3, respectively), 0.2 g/kg Taylor rhizomorph and a control feed. Results The body weight and body weight gain were higher in chicks fed 1,3-1,6 beta-glucan and Taylor rhizomorph than in control group. Feed conversion ratio significantly differed for G2 and G3 groups in comparison to control group. The relative weight of bursa was higher in G1, G2, and G3 groups. The white blood cells and lymphocytes were significantly increased in groups fed 1,3-1,6 beta-glucan. The immunoglobulin G of serum peak appeared in the G3 group. The villous height of the duodenum was higher in 1,3-1,6 beta-glucan feed groups. In the jejunum, the villous height was higher in G2 and G3 groups and crypt depth for all the groups fed β-glucan. At ileum level the villous height and crypt depth was higher for groups G1, G2, and G3. Conclusion The growth performance of Haidong chicks is improved when 10 and 20 g/kg 1,3-1,6 beta-glucan is included in the diet; hence, it is suggested that 1,3-1,6 beta-glucan be included in poultry diet to reduce and replace the use of antibiotics.

The plasma β-carotene status of non lactating Holstein-Friesian cows in a commercial dairy was found to be deficient (mean 1.2 μg /ml). Subsequently three experiments were conducted to evaluate the influence of 300 and 500 mg β-carotene supplementation per cow per day commencing 21 days prior to expected calving date and continuing for 70 days after calving on reproductive performance and periparturient health. There were considerable fluctuations in plasma β-carotene concentrations in cows around the time of calving in both supplemented and unsupplemented animals. However plasma concentrations tended to decrease as calving approached and where at their lowest 10 days after calving. β-carotene supplements significantly decreased the incidence of retained placenta, mastitis and reduced the days from calving to fi rst heat.

An experiment was conducted to study the influence of isoamylase supplementation to maize-soybean diets on productive performance and amylase activities of broilers from 1 to 42 d of age.The results showed that different dose of isoamylase（300g/T,600 g/T,900 g/T, containing 3000IU of isoamylase/g）in the maize - soybean meal diet significantly affected the performance of broilers within 1-42 days. Within 1-21 days , the average daily gain(ADG) of experimental groups( experiment I (E I) experiment II (E II) experiment III (E III) ) improved by 3.2% -10.32%(P>0.05) compared with the control groups(negative control(NC) and positive control(PC)), average daily feed intake(ADFI) improved by 0.63%-7.43%(P>0.05), while feed conversion ratio decreased by 0.55%-4.43%(P>0.05); Within 21-42 days , the ADG of experimental groups decreased by 1.38%-4.84% and ADFI by 11.89%-15.58% (P<0.05), feed conversion ratio by 5.41%-7.54% compared with that in the NC group; Within 1-42 days , the ADG of experimental groups improved by 0.54%-4.06%(P>0.05), while ADFI decreased by 0.75%-11.83% (P<0.05), and feed conversion ratio by 3.97%-7.52% (P>0.05) compared with those in the negative control. Isoamylase supplementation influenced amylase activity of various parts of the chyme in digestive tract and the tissues of small intestine and pancreas. 21 d, the amylase activity in experimental groups improved by 4.67%-79.29%(P<0.05) compared with PC, α-amylase activity in the majority experimental groups were lower than PC group, but the difference was not significant(P>0.05).