Effects of corn particle size on growth performance, gastrointestinal development, carcass indices and intestinal microbiota of broilers.

This experiment was conducted to investigate the effects of different corn particle sizes on growth performance, gastrointestinal development, carcass processing yields and intestinal microbiota of caged broilers. One-day-old Ross 308 broilers were randomly divided into 8 treatments with 10 replicates per treatment and 30 birds per replicate pen. The experiment lasted 37 d. Feed and water were provided ad libitum. The results showed as follows: birds fed diets with the FG corn between d 1 and 13 and CG corn between d14 to 37 had increased body weight, daily gain, and feed intake (P < 0.05). Birds fed diets with CG corn between d 24 to 37 had a heavier relative weight of gizzard at d 38 (P < 0.05). Birds fed diets with FG corn from d 1 to 13 and the CG corn from d 14 to 37 had a higher carcass yield and a relative thigh weight at d 38 (P < 0.05). The intestinal microbiota was significantly affected by different corn particle sizes. The relative abundance of Lactobacillaceae was significantly decreased, whereas that of Peptostreptococcaceae was increased (P < 0.05) in birds fed with the CG corn between d1 to 37. The relative abundance of Acinetobacter was significantly increased in birds fed the FG corn between d1 to 37 (P < 0.05). In conclusion, the use of FG corn in the starter phase and CG corn in the grower and finisher phases was beneficial to growth performance, gastrointestinal development and intestinal microbial structure of broilers reared in cages.

Effects of rearing system and narasin on growth performance, gastrointestinal development, and gut microbiota of broilers.

This study was conducted to evaluate the effects of 3 rearing systems (FL: flooring litter rearing, MC: multilayer cage rearing, PN: plastic net rearing) with or without supplemental narasin on growth performance, gastrointestine development and health of broilers. A total of 2,400 one-day-old Ross 308 mixed-sex broilers (1:1 ratio of males and females) were used in a completely randomized design utilizing a 3 × 2 factorial arrangement of treatments, with 12 replicates per treatment. Each replicate for FL, MC, and PN consisted of 34 birds per floor pen, 30 birds per cage, and 36 birds per net pen, respectively, ensuring the same stocking density (12 birds/m2) across the 3 systems. Results showed that lower ADG (average daily gain), ADFI (average daily feed intake), and FCR (feed conversation ratio) observed in the MC group than those of the other 2 systems from 1 to 36 d of age (P < 0.05). Narasin inclusion in the diets decreased ADFI and FCR significantly (P < 0.05). Multilayer cage and PN rearing systems reduced the relative weight of the gizzard significantly (P < 0.05). Compared with FL, MC reduced the relative weight of the duodenum, jejunum, and ileum (P < 0.05). The mRNA expression levels of the ileal IL-1ß and IFN-γ in FL were higher than those in PN and MC (P < 0.05). Narasin decreased the ileal mRNA expression of TNF-α (P < 0.05). Different rearing systems changed the ileal microflora structure of broilers. The FL system increased the ileal microbial diversity of broilers and the relative abundance of Actinobacteria. Narasin combined with MC increased the relative abundance of Proteobacteria. In conclusion, birds reared in PN had a higher body weight. The MC birds had poorer intestinal development and health condition, higher abundance of Proteobacteria, but better FCR. The FL rearing appeared to be propitious for gastrointestinal development and health. Narasin inclusion in the diets improved FCR and changed the relative abundance Proteobacteria of broilers.

Research on the correlation between the polymorphism of the back-2 gene and osteoarthritis.

OBJECTIVE: The objective of the present study was to investigate the correlation between polymorphisms of the back-2 gene and osteoarthritis. PATIENTS AND METHODS: We enrolled 76 patients with osteoarthritis who were admitted to our hospital between February 2014 and February 2015 for treatment as the observation group, and 46 healthy subjects as the control group. The analysis of back-2 gene polymorphisms (rs28502) was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). mRNA expression of the different genotypes was measured with reverse transcriptase-polymerase chain reaction (RT-PCR), and the protein expression of back-2 of different genotypes was measured with enzyme-linked immunosorbent assay (ELISA) and Western blotting. RESULTS: At locus 173 of the back-2 gene, there were a total of three genotypes, i.e. CC, CT, and TT. The frequencies of these genotypes in healthy subjects and osteoarthritis patients were 9.5%, 82.2%, 8.3% and 47.4%, 7.5%, 45.1%, respectively. There was a significant difference (p<0.05). However, the frequency of C/T in healthy older subjects and osteoarthritis patients was 50.6%, 49.4%, 51.15%, 48.85%, respectively, and there was no significant difference (p>0.05). RT-PCR showed no significant difference in mRNA expressions of the back-2 gene between the control group and observation group (p>0.05), although ELISA indicated that the protein expression of back-2 (12.3±0.36 µg/L) in osteoarthritis patients was significantly higher than in healthy subjects (1.52±0.18 µg/L) (p<0.05). Moreover, Western blotting analysis indicated that the protein expression of back-2 in osteoarthritis patients was significantly higher than in healthy subjects. CONCLUSIONS: Genetic polymorphisms of back-2 are associated with the metabolic syndrome in older people, i.e. older people with the CC or TT genotypes may be at high risk for metabolic syndrome.