This study was conducted to determine the effects of probiotics supplementation on growth performance, nutrient digestibility, occurrence of diarrhea and immune response in weaning pigs. Treatments were 1) NC (basal diet), 2) PC (basal diet + 0.12% avilamycin) and 3) A (basal diet + 0.2% Aspergillus oryzae), 4) B (basal diet + 0.2% Lactobacillus casei), 5) C (basal diet + 0.2% Bacillus subtilis), 6) D (basal diet + 0.2% Lactobacillus crispatus). A total of 120 pigs (7.16 ± 0.01 kg average body weight, weaned at 23 ± 3 days of age) were assigned to 6 treatments, 5 replicates and 4 pigs per pen in a randomized complete block (RCB) design. During the whole experimental period, body weight (P<0.01), average daily gain (ADG; P<0.01), and average daily feed intake (ADFI; P<0.05) of treatment PC were higher than other treatments. However, the probiotics treatments tended to increase ADG and G:F ratio compared to treatment NC. The G:F ratio in treatment A (Aspergillus oryzae) was similar to treatment PC during the whole experimental period (P<0.05). The supplementation of probiotics in the diet of weaning pig did not change nutrient digestibility (dry matter, crude protein, crude fat and ash) and nitrogen retention of weaning pigs. In blood urea nitrogen (BUN) concentration, treatment B had lower value than other treatments at 2 and 4 weeks (P<0.05). Treatments PC and C tended to decrease diarrhea score than other treatments (P=0.18). At 3h after lipopolysaccharide (LPS) injection, treatments NC and PC had higher count of CD4 + T-cells than probiotics treatments, and treatment C showed the lowest value (P<0.01). There were no differences on count of CD8 + T-cells and CD4 + :CD8 + ratio among all treatments (P>0.10). These results suggest that the dietary probiotics are likely able to improve the growth performance, occurrence of diarrhea and immune response although they do not have similar effects like antibiotics in weaning pigs.

A β-galactosidase-producing bacterium, strain KNOUC114 isolated from a hot spring was identified, and its gene of β-galactosidase and properties of the enzyme were studied. The strain KNOUC114 showed typical properties of genus Thermus with phenotypic characteristics of rod-shape (0.2x3.5μm), Gram negative, non-motile, endospore not observed, forming yellow-pigmented colonies, growing aerobically and optimally at 68-70℃. The strain could grow at the temperature above 80℃, which is a typical characteristic of Thermus thermophilus. The main cellular fatty acids of KNOUC114 were isobranched-C 17:00 and C 15:00 fatty acids that are the predomonant acyl chains of the strains of genus Thermus. In pylogenetic analysis based on 16S rDNA sequence, the strain KNOUC114 was finally identified as Thermus thermophilus species, and named as Thermus thermophilus KNOUC114. The β-galactosidase gene of KNOUC114 (KNOUC114β-gal) was cloned and expressed in Eschericia coli. 72,784 dalton. The purified recombinant β-galactosidase of KNOUC114 (KNOUC114β-gal) reacted optimally at pH 5.7 and 85℃, possessed good activity at the pH of raw milk and the temperature of HTST for raw milk, and was stable at the temperature of HTST and at the pH of raw milk, meaning that KNOUC114β-gal is suitable to be used for hydrolyzation of lactose in raw milk during HTST pasteurization of raw milk.

Objective: This experiment evaluated the effect of dietary supplementation levels of rapeseed meal (RSM) in gestation diets on reproductive performance, blood profiles, milk composition of sows, and growth of their progeny. Methods: A total of 55 mixed-parity sows (Yorkshire×Landrace; average parity = 3.82) with an initial body weight (BW) of 193.0 kg were used in this experiment. Sows were allotted to one of 5 treatments at breeding based on BW and backfat thickness in a completely randomized design. Treatments consisted of dietary RSM supplementation levels (0%, 3%, 6%, 9%, and 12%) in gestation diets. During lactation all sows were fed a common lactation diet with no RSM supple mentation. Results: Body weight, backfat thickness, litter size, lactation feed intake, and milk composition of sows, and growth of their progeny were not different among dietary treatments. In blood profiles, a quadratic increase (Quadratic, p<0.05) in serum triiodothyronine (T3) concentration and a linear increase (Linear, p<0.01) in serum thyroxine (T4) concentration were observed at d 110 of gestation as dietary RSM supplementation levels increased. However, serum T3 and T4 concentrations in lactating sows and their piglets were not affected by RSM supplementation of gestation diets. Concentrations of serum total cholesterol and low density lipoprotein cholesterol in sows were not influenced by dietary treatments, whereas serum glucose level in sows decreased linearly at d 110 of gestation (Linear, p<0.05) by increasing dietary RSM supplementation in gestation diets. Conclusion: The RSM could be supplemented to gestation diets up to 12% with no detrimental effects on reproductive performance and growth of their progeny. However, increasing supple mentation levels of RSM in gestation diets may increase serum T3 and T4 concentrations and decrease serum glucose concentration of sows in late gestation.