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1.
The effect of vitamin E on pig meat quality was investigated using British Landrace (NN and nn), Landrace × Large White (NN and Nn) and Pietrain (nn) pigs. Daily dietary supplementation of 500 mg vitamin E/kg diet for 46 days could reduce drip loss in unfrozen longissimus thoracis (LT) by 45% and 54% in Nn and NN pigs, respectively. In PSE-prone Landrace × Large White Nn pigs, daily supplementation of 1000 mg vitamin E/kg diet for the same period could significantly (P < 0.001) reduce excess release of Ca(2+) and prevent the formation of PSE carcasses, evaluated from both biopsy and post- mortem LT samples. Experimental evidence from erythrocyte fragility and water-holding capacity of biopsy LT samples suggested that vitamin E improved pig meat quality by its ability to stabilize membranes. Stabilization of membrane integrity in isolated mitochondria of LT by vitamin E was associated with inhibition of phospholipase A(2) activity.  相似文献   

2.
A new in-vivo procedure for predicting the potential meat quality in live pigs was devised using stress-susceptible (halothane positive) and stress-resistant (halothone negative) pigs. The potential meat quality in live pigs was determined using small biopsy samples of M. longissimus dorsi (LD). Meat quality was assessed by the combined measurements of pH and water-holding capacity (WHC) on the 12 000 g supernatant after incubation of 500 mg biopsy LD muscle with an equal volume of 150 mm KCl at 39°C for 45 min. With the LD muscles of halothane positive (n = 37) and halothane negative (n = 55) pigs, high correlations (r = -0·854) were observed between the supernatant (i.e. fluid) pH and WHC of the biopsy samples, between fluid pH of the biopsy samples and 1-h post-mortem (pH(60)) LD muscles (r = 0·951), and between pH(60) and WHC (r = -0·956). The experimental data show that our in-vivo test can differentiate halothane positive from halothane negative pigs and can also predict the potential meat quality in live pigs. The test could be applied to select pigs with differences in WHC to improve meat quality.  相似文献   

3.
Cheah KS  Cheah AM  Just A 《Meat science》1998,48(3-4):249-255
RSE (reddish-pink, soft and exudative) meat was investigated using pigs of three different halothane genotypes. A significantly lower pH1h, value was observed in RSE compared with that of RFN (red, firm and non-exudative) -meat, both of which have values higher than 6.0 at 1 hr post-mortem. Drip loss (%) in RSE-meat was ≥7%, which was twice that of RFN-meat. Normal values for fibre optic probe and Minolta L and a were observed for RSE-meat. RSE-meat could be derived from NN and Nn pigs, and its formation could be induced from RFN-prone pigs by poor post-slaughter management. Pigs expected to produce RSE-meat were identified using small biopsy samples of M. longissimus dorsi (LD). Predicted RSE-meat in live pigs was confirmed by post-mortem assessments of meat quality using LD muscle. With NN Landrace-Yorkshire × Duroc pigs, 15.6% were identified to be RSE-prone in live pigs, and a further 6.7% RSE was induced after slaughter from RFN pigs. The rate of glycolysis determined from biopsy LD samples and at 1 hr post-mortem (pH1h) were significantly (p < 0.001) faster in RSE than in RFN-prone pigs, but significantly slower than those of PSE-prone pigs. Good correlations (p < 0.001) were observed between biopsy fluid (F) values, an indicator of water-holding capacity (WHC), and drip loss (r = 0.652) from post-mortem LD muscle, and between biopsy pH (F), an indicator for the rate of glycolysis, and F (r = −0.828). These results show that the skeletal muscle test using biopsy LD muscle could be employed to reduce the incidence of RSE-meat.  相似文献   

4.
Seventy-six Landrace and four Large White × Landrace pigs (n=80) of 90-134 kg liveweight were randomly allocated to a 2×2×2 factorial experiment to determine the effect of halothane genotype [heterozygous for the halothane gene (Nn) and homozygous dominant (NN)], pre-slaughter handling (minimal and negative) and stunning method (CO(2) stunning and electrical) on pork quality. The rate of muscle pH decline post-slaughter of the m. longissimus thoracis et lumborum (LTL) muscle was faster in Nn pigs compared with NN pigs (0.86 and 0.30 pH units/h, respectively). Pork from Nn pigs was also paler in colour, had higher percentage drip loss and purge and lower sarcoplasmic and myofibrillar protein solubility compared with NN pigs. Pork from CO(2) stunned pigs had a lower drip loss compared to pork from electrically stunned pigs (5.80 and 7.28%, respectively?- means of both genotypes combined). Tenderness of pork assessed at 24 h post-slaughter was not influenced by genotype, pre-slaughter handling or stunning method. However, pork from Nn pigs aged for 5 days post-slaughter was less tender than NN pigs (5.84 and 4.84 kg, respectively). Pale, soft and exudative pork was produced in all negatively handled Nn pigs, regardless of stunning method. The average amount of ecchymosis-affected muscle trimmed from carcasses of electrically stunned pigs was higher compared to pigs stunned with CO(2) (65 and 0.7 g, respectively). These data indicate that although halothane status was the most important factor influencing pork quality, pre-slaughter handling and stunning method also influenced meat and carcass quality.  相似文献   

5.
The objective of this work was to compare the quality of carcass and meat in the selected crossbred pigs used in the Czech Republic. A total of 200 pigs that arose from four crossbreeding was studied; the dam line was in all combination of hybrids represented by Czech Large White × Landrace. Sire line included Large White × Belgian Landrace (I), Hampshire × Pietrain (II), Duroc × Pietrain (III) and Czech meat pig (IV). Influence of crossbreeding on lean meat percentage and muscle depth was statistically highly significant (P<0.001), influence on fat depth was evident (P<0.05). Differences in pH(1) value among the individual final hybrids were not statistically significant but variance of pH(24) value was highly notable (P<0.001). All colour parameters (L(?), a(?), b(?) values), drip loss and exudate also were influenced by hybrid combination (P<0.001). Influence of crossbreeding on intramuscular fat content was not statistically significant (P=0.067). Higher content of intramuscular fat was determined in the hybrids with Duroc breed in sire line. In the whole group, 8.5% pig with PSE defect was found. By comparison of all the various hybridisation, positive influence of Hampshire breed on the carcass quality and negative influence on meat quality was confirmed. On the other hand, meat quality is positively influenced Duroc and Czech meat pig breeds.  相似文献   

6.
This study considers the effect of crossbreeding and gender (barrows; gilts) on meat quality and intramuscular and subcutaneous fatty acid composition in pork. The sire lines included Large White (LW), Duroc (D) and Pietrain (P) and the dam line was Landrace (LR)×LW, producing LW×(LR×LW), D×(LR×LW) and P×(LR×LW). Pork samples were removed from Longissimus dorsi (LD) and Semimembranosus (SM) muscles and subcutaneous fat (SCF). There were no important differences in meat quality parameters but D×(LR×LW) had the highest percentage of intramuscular fat. Castrated males had more intramuscular fat and more intense meat colour than female pigs. The Large White and Duroc sire line had saturated fatty acids (SFA) in SM, whereas the Pietrain sire line was significantly higher than Duroc sire line in the concentration of polyunsaturated fatty acids (PUFA), PUFA/SFA (P/S) and the n-6/n-3 ratio. The concentrations of SFA and monounsaturated fatty acids (MUFA) in SCF were significantly higher in LW×(LR×LW) and P×(LR×LW), respectively. No differences were found in the percentage of PUFA, P/S and n-6/n-3 ratio between D×(LR×LW) and P×(LR×LW). Female pigs had the most polyunsaturated intramuscular and subcutaneous fat. The results demonstrate small differences in fatty acid compositions among sires.  相似文献   

7.
The effect of the halothane gene on cured meat products was investigated using the meat from 60 Landrace×Large White pigs of known halothane genotype (NN=25, Nn=19, nn=16). The backs and hams were used to prepare cured, smoked bacon and canned hams. Initial bacon gain in pumped weight was significantly higher (P<0.001) for the NN (15.2%) and Nn (14.9%) compared to the nn pigs (8.9%). Similarly, the total gain in bacon yield was the highest for the Nn (11.5%) and NN pigs (10.0%), and significantly higher (P<0.05) than the bacon from nn pigs (3.4%). Differences between sexes were not significant. Canned hams (no phosphate) from the NN genotype had a significantly (P<0.001) lower percentage cooking loss (27.9%) compared to the Nn (30.1%) and nn pigs (31.1%), which did not differ statistically. Although addition of phosphates (0.3% on final product) led to a decrease in percentage cooking loss, the genotypes gave a similar response, with the NN genotype having 13.8% cooking loss, significantly lower (P<0.001) than the Nn (16.9%) and nn genotypes (17.7%). The results indicate reduced product quality with the inclusion of the halothane gene.  相似文献   

8.
Carcass composition and meat quality were compared in Chinese purebred native pigs (Meishan and Ming) and the same breeds crossed with Landrace. Duroc × Landrace were controls. The study was part of a programme to improve pig production in Japan by introducing Chinese native pigs. The loin meat from Chinese purebred pigs received higher sensory scores than that from crosses between Landrace and Duroc (abbreviated as LD). Separable fat percentage of the carcass from Chinese purebred pigs was about 2·5 times higher than that from LD pig. This separable fat was decreased by crossbreeding with Landrace. Water-holding capacity (WHC) of the meat from Chinese purebred and crossbred pigs was slightly higher than that from LD. Significant difference in the contents of amino acids and peptides was not observed among the species examined. Contents of inosinic acid (IMP), one of the flavour components, in the meat from Chinese purebred and crossbred pigs were higher than that from LD. From histochemical observation, an unusual distribution of fat in the muscle fibre was observed in the muscle from Chinese purebred pigs, especially Ming, as compared with other species.  相似文献   

9.
The effect of the halothane gene on cured meat products was investigated using the meat from 60 Landrace×Large White pigs of known halothane genotype (NN=25, Nn=19, nn=16). Results for the two types of fresh sausage manufactured (with and without rusk) indicated that the NN pigs (15.7%) had lower total moisture losses (P<0.05) compared to the nn pigs (18.9%), with Nn being intermediate (17.4%) for the sausage without rusk. Where rusk was added, there were no significant differences between genotypes for moisture losses (NN=12.6%, Nn=13. 0%, nn=14.2%). Taste panel evaluations of the fresh sausages made without rusk indicated no genotypic influence for juiciness, however the sausage made with the rusk was judged the juiciest for the nn genotype, with Nn being intermediate and NN the least juiciest. The smoking and cooking losses during manufacturing of the emulsion product (vienna) indicated that the nn genotype (12.5%) had significantly (P<0.05) higher total losses than the Nn genotype (11. 3%), with NN being intermediate (12.4%).  相似文献   

10.
Phosphorus nuclear magnetic resonance ((31)P NMR) measurements were made to determine muscle energetic metabolism on muscle biopsy samples of heterozygote malignant hyperthermia (Nn) and normal (NN) pigs DNA tested on occurrence of mutation in RYR 1 gene. Biopsy samples (approx. 1 g) were obtained by spring-loaded biopsy instrument (Biotech, Slovakia) from Longissimus dorsi (LD) muscle at 80 kg live weight. The spectra were recorded at 121 MHz on a VXR 300 (Varian) spectrometer in 10 mm diameter tube (maintained at 39?°C) for 50 min. pH of bioptates after NMR measurements were also measured at 60 min. The changes in inorganic phosphate (Pi), phosophocreatine (PCr) and adenosine triphosphate (ATP) were faster in heterozygote malignant hyperthermia (MH; 29 crossbred White Meaty×Pietrain) than in normal (13 Duroc, Yorkshire and White Meaty). The values of PCr at 20 min and pH at 60 min after taking biopsy allowed discrimination between NN and Nn pigs and significant (P<0.05) differences were also found between two subgroups in heterozygote MH pigs with different rate of post mortem muscle metabolism. The values of PCr and pH as measured at definite time on the biopsies, were significantly (P<0.05) correlated with the rate of post mortem metabolism (pH) and with meat quality traits (r approx. 0.4-0.6). The (31)P NMR measurements pointed to impaired muscle energetic metabolism connected with the occurrence of mutation on the RYR 1 gene in heterozygote MH pigs.  相似文献   

11.
Phosphorus nuclear magnetic resonance (31P NMR) measurements were made on biopsy samples from pig muscles. Two experiments were performed, one in France and one in Czechoslovakia. In experiment 1, the muscle samples were obtained by surgery from the Biceps femoris muscle of 10 pigs with various genetic types (5 Large White, 1 Large White × Landrace, 4 Pietrains). In experiment 2, the muscle samples were obtained by shot biopsy from the Longissimus dorsi muscle of 11 Belgian Landrace × Duroc pigs, of which 6 were halothane-negative and 5 halothane-positive. The pigs were slaughtered by electrostunning and exsanguination respectively 3 weeks and 1 week after the biopsy, and meat quality traits (pH1, reflectance and water holding capacity) were determined. The changes in adenosine triphosphate (ATP), creatine phosphate (CP), inorganic phosphate (Pi) and pH, as deduced from NMR, were faster in Pietrains than in Large Whites, and in halothane-positive than in halothane-negative pigs. The value of the CP/Pi ratio at 40 min after taking biopsy allowed discrimination between halothane-positive and halothane-negative pigs. The values of pH, creatine phosphate and adenosine triphosphate, as measured at definite times on the biopsies, were correlated with the rate of post-mortem metabolism (r approx 0·8) and with meat quality traits. 31P NMR measurements combined with a rapid and efficient biopsy technique appear as an alternative tool for assessment of both halothane sensitivity and prediction of meat quality in pigs.  相似文献   

12.
The carcass and meat quality characteristics of three halothane genotypes in pigs were evaluated. Sixty crossbred Landrace×Large White pigs (NN=25, Nn=19, nn=16) of ±86 kg live weight were slaughtered, the carcasses chilled for 24 h at 2°C, certain carcass and meat quality traits determined and the shoulder and leg cuts deboned and cut into primal cuts. Dressing percentage of the Nn pigs was higher (P<0.05) than that of the NN and nn pigs. Carcass length was the longest (P<0.05) for the nn pigs. Midline fat measurements as well as measurements at the 2nd-3rd last rib (45 mm from the midline) indicated that the nn pigs had less fat (P<0.05) and a larger eye muscle width (P<0.05), depth (P<0.001) and area (P<0.001) than the NN or Nn pigs. This resulted in the nn pigs having the highest (P<0.05) percentage predicted carcass lean content. Fat, bone and lean yield of the shoulder identified the nn pigs with the least bone (P<0.05) and fat (P<0.001) and the highest lean yield (P<0.05), expressed as a percentage of total shoulder weight. Yield from the legs identified the nn pigs as having the lowest fat (P<0.001) and highest lean (P<0.05), expressed as a percentage of total leg weight. The primal lean cuts (topside, silverside, thickflank and rump) from the legs showed that the nn pigs had the highest values (P<0.05) for lean as a fraction of cold carcass weight. This resulted from the higher weight of these cuts (P<0.05) in the nn pigs. Calculation of bone yield in the legs showed that the femur weights were highest (P<0.05) for the Nn pigs, also when expressed as percentage of leg weight (P<0.05) and as a fraction of cold carcass weight (P<0.05). Comparison of meat quality traits show that the nn pigs had poor quality with regard to pH(45) (P<0.001), pH(24) (P<0.05), drip loss (P<0.001) and reflectance values (P<0.05).  相似文献   

13.
This study aimed to investigate the genes PPARGC1A (peroxisome proliferator-activated receptor gamma-coactivator 1A) and CAPNS1 (calpain small subunit 1) as candidate genes affecting meat quality traits in pigs. Four polymorphisms were identified in PPARCG1A and three in CAPNS1. The PPARGC1A polymorphism c.1288T>A was associated with pH and cooking loss in a F2 Duroc×Pietrain experimental cross (DuPi, n=313) and with pH values in Italian Large White (ILW, n=380) and Italian Landrace (ILA, n=158) populations (P<0.05). The CAPNS1 polymorphism c.429A>C was associated with pH and conductivity in DuPi and with meat color in ILA (P<0.05). PPARGC1A mRNA expression associated with drip loss (P<0.01) and the same tendency was found for CAPNS1 (P=0.06). The promoter methylation profiling suggested that methylation is not involved in CAPNS1 expression regulation. In conclusion, porcine PPARGC1A and CAPNS1 genes may affect meat quality traits, with breed-specific differences, and they could be used as markers for the improvement of meat quality in pigs.  相似文献   

14.
This study was performed in order to investigate a relationship between polymorphism's of calapastatin gene (CAST) identified with HinfI, MspI and RsaI restriction endonucleases in pigs and meat quality characteristics and also interactions between CAST and RYR1 genes. Investigations were carried out on group of 89 fatteners being crosses of (Polish Large White×Polish Landrace)×(Hampshire×Pietrain). Some meat quality characteristics, glycolytic potential of LL muscle, yield of curing meat in cooking, the yield of loin in curing and smoking processes were determined. Statistically significant influence of RYR1 genotype (CC and CT) on investigated traits wasn't affirmed. A significant effect of CAST genotype on the value of several meat quality traits was noticed. Interactions between RYR1 and CAST genes were statistically significant for pH(45) value (CAST/RsaI×RYR1) and for drip loss (CAST/HinfI×RYR1). Obtained results showed that glycogen level in LL muscle in 45 min post mortem depends on CAST/MspI and CAST/RsaI genotypes while glycolytic potential depends on CAST/RsaI genotype. Genotyp AA at CAST/RsaI locus and AA genotype at CAST/HinfI locus stopped disclose of effect of RYR1 gene mutation for pH(45) in LD muscle and for drip loss respectively. Animals heterozygous in RYR1 locus (CT) being BB homozygotes at CAST/RsaI locus produced meat with highest pH(45) value (6,4) and dark meat colour. For technological properties of meat most interesting are double heterozygotes at the loci RYR1 and CAST/HinfI with significantly lowest (P?0.01) drip loss (4,04%).  相似文献   

15.
The influence of terminal sire (Duroc (D1 and D2), Large White/Pietrain (LW/P) and Large White (LW)) on several meat production and meat quality traits was investigated in 452 male and female offspring of Landrace/Large White dams. Age at slaughter, carcass length, carcass weight and dressing yield were similar for all lines, as was the production of shoulders, chops, and ribs with bacon. D2‐sired pigs produced more noble pieces as a percentage of their carcass weight than the other three lines. LW/P‐ and LW‐sired pigs were generally leaner than Duroc‐sired pigs. LW/P and LW pigs had the highest percentage of cuts (longissimus dorsi and semimembranosus muscle) classified as pale, soft and exudative (PSE) meat. There were no large differences between the lines in the occurrence of dark, firm and dry (DFD) cuts. Copyright © 2003 Society of Chemical Industry  相似文献   

16.
Pigs from crosses of a Piétrain (Pi) and a Large White×Piétrain (LwPi) heterozygous (Nn) boar lines with Landrace×Large White homozygous negative (NN) sows, were used to study the effect of halothane gene and pre-slaughter treatment on animal welfare and meat quality. A total of 83 gilts (47 NN and 36 Nn) were assigned to a long treatment (3 h 15 min transport and 12 h lairage) and 73 (39 NN and 34 Nn) to a short treatment (30 min transport and 2 h lairage). Heart rate was recorded throughout loading and transport. Blood samples were collected before loading, after transport, and at exsanguination to measure cortisol, creatine phospho-kinase (CPK) and lactate dehydrogenase (LDH). Carcasses were classified and commercial cutting was carried out. Meat quality was assessed on the Longissimus thoracis muscle by measuring electrical conductivity (PQM), colour (Minolta CR 200 and Japanese scale) and ultimate pH. Loin drip losses were assessed at 24 h. Halothane carriers showed a higher increase in cortisol levels after transport and exsanguination in the long treatment (P<0.05) as well as in LDH and CPK after exsanguination in the short treatment (P<0.05). In this treatment, halothane-free pigs recovered during lairage when comparing LDH and CPK increases after exsanguination to their increases after transport. No effect of the halothane gene on heart rate was observed. Pi sired pigs were leaner and had higher yields of leg and loin compared with LwPi sired pigs (P<0.001), but no differences in meat quality were observed between crosses. Halothane carriers had a higher estimated lean content (P<0.01) and shoulder and leg yields (P<0.01), but poorer meat quality than non-carriers (i.e. higher incidence of PSE meat, P<0.001). Although pre-slaughter treatment and halothane genotype did not significantly affect pHu, significantly higher L*, a* and b* values found in the short treatment and Nn individuals indicated paler meat. These results suggest that for improving meat quality and welfare the halothane gene should be removed from breeding schemes.  相似文献   

17.
The three halothane genotypes (NN, Nn, and nm) were identified by measuring the capacity for Ca2+ accumulation by sarcoplasmic reticulum in whole muscle homogenate preparations of M. longissimus dorsi with a Ca2+ specific electrode at 35°C. Significant differences (P < 0·001) in deterioration (%) of Ca2+ accumulation, 12% for NN, 35% for Nn, and 81% for nn pigs, were observed after ageing the whole muscle homogenate preparations for 24 h in ice.

Predictions of meat quality in live pigs (n = 34) based on the values for water-holding capacity, assessed as fluid (g/0·5 g wet wt LD), and pH (fluid) by using small biopsy LD samples (Cheah et al. 1993) were performed on all the halothane genotypes. The halothane genotype NN (n = 11) showed a fluid value of 0·37 ± 0·01 and a pH (fluid) value of 6·62 ± 0·03 as compared with 0·61 ± 0·02 and 5·84 ± 0·04, respectively, for the halothane genotype nn (n = 13). The Nn pigs (n = 10) showed fluid (0·49 ± 0·03) and pH (fluid) (6·19 ± 0·11) values between those values observed for the two homozygotes (NN and nn). Predictions of meat quality in live pigs from biopsy LD muscles were confirmed from assessments on post-mortem LD muscles based on pH1 and fibre optic probe (FOP) measurements.

The extent of deterioration (%) in Ca2+ accumulation showed high correlations with fluid (r = −0·861) and pH (fluid) (r = −0·831) in the biopsy LD samples, and with pH1 (r = 0·663), FOP (r = −0·812), and drip (%) loss (r = −0·777) in the post-mortem LD samples.  相似文献   


18.
Warriss PD  Lister D 《Meat science》1982,7(3):183-187
The value of giving pigs the beta-adrenergic blocking drug carazolol preslaughter to improve meat quality was tested in a stress-resistant breed (Large White) and a stress-susceptible breed (Pietrain). Pigs averaging about 70kg liveweight were injected intramuscularly (1 mg per 100 kg liveweight) 0·5h before being transported to the slaughterhouse. The journey lasted 4 h and covered about 150 km and the pigs were slaughtered after 1 h in lairage. Treatment with carazolol reduced the incidence of PSE meat and considerably improved meat quality in the stress-susceptible Pietrain breed but had little effect in the stress-resistant Large Whites which produced good meat quality in both control and treated groups.  相似文献   

19.
Meat from half-Chinese crossbred pigs was compared with meat from purebred European pigs for chemical composition and eating quality. In a first experiment, purebred Pietrain pigs were compared to Pietrain × Chinese (Meishan or Jia Xin ) pigs for sensory qualities as assessed by a taste panel. In a second experiment, purebred Large Whites were compared to Large White × Meishan pigs for chemical composition and eating quality as assessed by both taste panel and consumer testing. The lipid and collagen content in the meat were higher in the Large White × Chinese crossbred pigs than in the purebred Large White pigs. In both experiments, meat from half-Chinese cross bred pigs was judged more tender, more juicy and more tasty than meat from purebred European pigs by the taste panel as well as by consumers. However, the latter judged that the overall acceptability of the meat from half-Chinese pigs was not better, probably due to the excessive amount of visible fat.  相似文献   

20.
Isotachophoretic (ITP) measurements were made on biopsy samples from live muscle M. longissimus lumborum and carcasses of pigs. Two experiments were performed. In Experiment 1, the methodological aspects of ITP measurements from skeletal muscle, were studied. In Experiment 2, ITP measurements on muscle and carcass samples were made. The muscle and carcass samples were obtained by shot or spring-loaded biopsy from the Longissimus lumborum muscle of 30 Belgium Landrace × Duroc pigs, of which 10 were halothane-positive. The pigs were slaughtered by electro-stunning and manguination at approximately 105 kg body l. w.

The potential meat quality in live pigs and after slaughter using small biopsy samples of M. longissimus lumborum was also determined. The experimental results show that ITP (mainly inosinemonophosphate and lactate) and meat quality data (water-holding capacity test, pH and R value) can differentiate halo thane-positive from halothane-negative pigs. Out results confirmed previous results which showed that the water-holding capacity test defined as fluid volume', pH and R value measurements on biopsy samples can also predict the potential meat quality in live pigs.  相似文献   


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