The influence of dietary supplementation with blended essential oil on growth performance, nutrient digestibility, blood profiles and fecal characteristics was evaluated in 125 crossed ((Duroc×Yorkshire)×Landrace) pigs (6.21±0.20 kg initial body weight and 21 d average age). The pigs were allotted to the following treatments: i) NC (antibiotic free diet), ii) PC (NC diet+44 ppm tylosin), iii) T1 (NC diet+0.1% essential oil), iv) T2 (NC diet+0.1% essential oil (with 0.3% Benzoic acid)) and v) T3 (NC+22 ppm tylosin and 0.05% essential oil). Average daily gain (ADG) was improved in the T2 group on d 14 (p<0.05). In addition, nutrient digestibility was partially affected (both positively and negatively) by the treatments. Furthermore, the immune system was stimulated and the fecal pH and fecal noxious gases were improved in pigs that received the diets supplemented with essential oil (p<0.05). The appearance and score of diarrhea also tended to be lower in pigs that were subjected to the essential oil treatments. Collectively, the results of this study indicate that supplementation of the diet with blended essential oils could replace treatment with antibiotics to improve growth performance and fecal characteristics.

A total of 96 growing pigs ((Landrace×Yorkshire)×Duroc; BW = 26.58±1.41 kg) were used in a 6-wk feeding trail to evaluate the effects of fermented chlorella (FC) supplementation on growth performance, nutrient digestibility, blood characteristics, fecal microbial and fecal noxious gas content in growing pigs. Pigs were randomly allotted into 1 of 4 dietary treatments with 6 replicate pens (2 barrows and 2 gilts) per treatment. Dietary treatments were: i) negative control (NC), basal diet (without antibiotics); ii) positive control (PC), NC+0.05% tylosin; iii) (fermented chlorella 01) FC01, NC+0.1% FC, and iv) fermented chlorella 02 (FC02), NC+0.2% FC. In this study, feeding pigs PC or FC01 diets led to a higher average daily gain (ADG) and dry matter (DM) digestibility than those fed NC diet (p<0.05), whereas the inclusion of FC02 diet did not affect the ADG and DM compared with the NC group. No difference (p>0.05) was observed on the body weight, average daily feed intake (ADFI), gain:feed (G:F) ratio, the apparent total tract digestibility of N and energy throughout the experiment. The inclusion of PC or FC did not affect the blood characteristics (p>0.05). Moreover, dietary FC treatment led to a higher (p<0.05) lactobacillus concentration and lower E. coli concentration than the NC treatment, whereas the antibiotic supplementation only decreased the E. coli concentration. Pigs fed FC or PC diet had reduced (p<0.05) fecal NH3 and H2S content compared with those fed NC diet. In conclusion, our results indicated that the inclusion of FC01 treatment could improve the growth performance, nutrient digestibility, fecal microbial shedding (lower E. coli and higher lactobacillus), and decrease the fecal noxious gas emission in growing pigs when compared with the group fed the basal diet. In conclusion, dietary FC could be considered as a good source of supplementation in growing pigs because of its growth promoting effect.

A total of 144 pigs ((Landrace×Yorkshire)×Duroc] with an average initial BW of 8.45±0.57 kg were used in a 5-wk growth trial. Pigs were randomly allocated to 4 treatments with 9 replications per pen in a randomized complex block design. Dietary treatments included: i) CON (basal diet), ii) ANT (CON+tylosin 1 g/kg), iii) H1 (CON+H. cordata 1 g/kg) and iv) T1 (CON+T. officinale 1 g/kg). In this study, pigs fed the ANT and T1 treatment had a higher (p<0.05) average daily gain (ADG) and gain:feed (G:F) ratio than those fed CON and H1 treatment. Dietary ANT and T1 treatment led to a higher energy digestibility than the CON group. No difference (p>0.05) was observed on the growth performance and apparent total tract digestibility with H1 supplementation compared with the CON treatment. The inclusion of ANT treatment led to a higher (p<0.05) lymphocyte concentration compared with the CON treatment. Dietary supplementation of herbs did not affect (p>0.05) the blood characteristics (white blood cell (WBC), red blood cell (RBC), IgG, lymphocyte). No difference was observed on (p<0.05) fecal microbial shedding (E. coli and lactobacillus) between ANT and CON groups. Treatments H1 and T1 reduced the fecal E. coli concentration compared with the CON treatment, whereas the fecal lactobacillus concentration was not affected by the herb supplementation (p>0.05). In conclusion, the inclusion of T. officinale (1 g/kg) increased growth performance, feed efficiency, energy digestibility similarly to the antibiotic treatment. Dietary supplementation of T. officinale and H. cordata (1 g/kg) reduced the fecal E. coli concentration in weaning pigs.