ABSTRACT
Objective To comparatively investigate the characteristics of bone metabolism in forelimb malformation WHBE rabbits based on the OPG/RANK/RANKL system.Methods Healthy male 2-2.5-month old WHBE rabbit ( HWR) , Healthy Japanese rabbit ( HJR) and forelimb malformation WHBE rabbit ( FMWR) were used in this study and divided into 3 groups, HWR, HJR and FMWR groups, with 10 rabbits in each group.The shape of forelimb and mean gray value observed from X-ray film were examined, and the bone tissue micro-morphology was analyzed using HE staining.Re-al-time fluorescence quantitative PCR was used to determine the expression of osteoprotegerin ( OPG) and receptor activator of NF-KB ligand ( RANKL) mRNA.The expressions of OPG, receptor activator of NF-KB ( RANK) and RANKL protein in serum and bone tissue were assayed by enzyme-linked immunoassay ( ELISA) and immunohistochemistry, respectively. Results Compared with the HWR and HJR groups, rabbits in the FMWR group appeared abnormal in toutuous forelimb and thinner bone cortex.The mean gray values of X-ray in the FMWR group were lower than that in the HWR group ( P<0.05).There were significant differences between the FMWR and healthy rabbits (HWR and HJR) in the following pa-rameters:RANKL mRNA expression and RANKL/OPG mRNA ratio in the liver(P<0.05, P<0.01), serum protein expression of RANK and RANKL and RANKL/OPG ratio (P<0.05, P<0.01), and positive index of expression of RANKL protein and RANKL/OPG ratio in the bone tissue(P<0.05, P<0.01).Furthermore, the gene expression lev-els of OPG and RANKL of HWR were significantly higher than that of HJR(P<0.05, P<0.01).Conclusions The FMWR show some abnormal symptoms in bone metabolism as well as decrease of bone quality and histological changes of bone micro-structure, due to the significant increase of RANKL/OPG ratio of FMWR.The breed differences between WHBE and Japanese rabbits in RANKL mRNA expression level may be one of factors inducing limb malformation in the WHBE rabbits.
ABSTRACT
Objective To investigate the effects of dried whey on the intestinal bacterial community and probiotics in weaned laboratory rabbits .Methods A single factor design was employed to investigate the effects of dried whey supplemented at levels of 0%, 2%, 5%and 10%, respectively, on 48 weaned (40-day-old) laboratory rabbits.At the day 30, eight rabbits in each group were taken and sacrificed after anesthesia .The total bacterial DNA from the ceacal content of each selected rabbit was drew to analyze the bacterial community and intestinal probiotics ( Bifidobacterium and Lactobacillius) population by PCR-DGGE and real-time fluorescence quantitative PCR, respectively.Results 1) The DGGE parameters of ceacal bacterial community were increased with the increasing dried whey supplemental levels .The number of DGGE band in 2%, 5%and 10%dried whey supplement groups (P0.05).Supplying dried whey has no significant effects on the homogeneity index (P>0.05).2) The population of Bifidobacterium and Lactobacillius in ceacal content had a trend of increase with the rising dried whey supplement levels .Compared with the 0% supplement group , the Lactobacillius population in the 2%, 5% and 10%supplement groups ( P <0.05 ) , the Bifidobacterium population in the 10% supplement group ( P <0.05 ) were significantly increased .Conclusions The results of our study indicate that: 1 ) Supplying dried whey in the feed of laboratory rabbit can effectively increase the diversity of ceacal bacterial community .2) Dried whey may effectively improve the intestinal probiotics population .