首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
To clarify the impact of feeding co-extruded flaxseed on carcass quality and pork palatability, 96 pigs (48 barrows and 48 gilts) were fed three different levels of flaxseed (0%, 5% and 10% of dietary intake) for 76 days. Carcass quality and meat quality characteristics of pure loin muscle and ground pork (20% fat) were evaluated. Fat hardness and belly firmness decreased (< 0.001) with increasing co-extruded flaxseed. Pigs fed co-extruded flaxseed levels had higher lean yield (= 0.045) and total lean content (= 0.034). Loin from barrows had higher fat content compared to gilts (< 0.001). Co-extruded flaxseed supplementation increased (< 0.001) omega-3 content in loin and ground pork. Pork flavour intensity and off-flavour intensity scores lowered (< 0.001) with increasing levels of co-extruded flaxseed, being more accentuated (= 0.023) in reheated pork chops from barrows. Diet affected all texture and flavour sensory characteristics (< 0.05) as tissue levels of omega-3 fatty acids increased, likely as a result of increased lipid oxidation.  相似文献   

2.
A microbiological survey was conducted to determine the levels of total and pathogenic Vibrio parahaemolyticus (Vp) and Vibrio vulnificus (Vv) in Pacific oysters (Crassostrea gigas) collected from commercial growing areas in the North Island, New Zealand.The survey was intended to be geographically representative of commercial growing areas of Pacific oysters in New Zealand, while selecting the time frame most likely to coincide with the increased abundance of pathogenic vibrio species. Vp was detected in 94.8% of oyster samples examined (n = 58) with a geometric mean concentration of 99.3 MPN/g, while Vv was detected in 17.2% of oyster samples examined with a geometric mean concentration of 7.4 MPN/g. The frequency of Vp positive samples was 1.7 fold greater than reported in a study conducted three decades ago in New Zealand. Potentially virulent (tdh positive) Vp was detected in two samples (3.4%, n = 58) while no trh (another virulence marker) positive samples were detected. 16 S rRNA genotype could be assigned only to 58.8% of Vv isolates (8:1:1 A:B:AB ratio, n = 10). There was a good agreement [98.2% of Vp (n = 280) and 94.4% of Vv (n = 18) isolates] between molecular tests and cultivation based techniques used to identify Vibrio isolates and there was a significant (R2 = 0.95, P < 0.001, n = 18) linear relationship between the MPN estimates by real-time PCR and cultivation. There was no significant correlation between any of the environmental parameters tested and Vp or Vv concentrations.  相似文献   

3.
Duration of soybean oil (SBO) supplementation needed to enhance carcass conjugated linoleic acid (CLA) and trans-vaccenic (TVA) content was examined using 96 beef steers (293.6 ± 3.9 kg) fed a 78% corn-based diet supplemented with SBO for 0, 77, 137, or 189 days before slaughter. Duration of SBO supplementation had no effect (P ? 0.15) on animal performance or carcass traits, nor (P ? 0.15), total, total saturated, or total polyunsaturated fatty acids of Longissimus dorsi (LD). Concentrations of CLA in LD were not affected (P ? 0.18) by SBO supplementation. Concentrations of monounsaturated fatty acids (MUFA) decreased linearly (P = 0.03) in LD, whereas TVA increased (P = 0.04) in adipose tissue and tended (P = 0.07) to increase in LD with increasing duration of SBO supplementation. Supplementing SBO to a concentrate-based diet may enhance TVA without impacting CLA, while reducing the MUFA content of lean beef.  相似文献   

4.
Production, carcass traits and meat quality of rabbits housed in cages or in different pens were compared. Rabbits (n = 579) were sorted into 5 groups: C = cage (2 rabbits/cage); pen without platform: P11 = 9 rabbits/pen; P16 = 14 rabbits/pen; pen with platform: PW = wire net platform, 14 rabbits/pen; PD = platform with straw-litter, 14 rabbits/pen. Feed intake and average daily gain between 5 and 11 weeks, and body weight at 11 weeks were significantly higher in C rabbits than that of the mean of pen-housed groups, while the PD group had the lowest growth performance. C rabbits had the smallest hind part to reference carcass (P < 0.001) and the largest percentage of perirenal and scapular fat (P < 0.001). The meat/bone ratio was the largest in group C (P < 0.05). Differences were recorded in a* value and lipid content of m. Longissimus dorsi. Rabbits housed in cages generally had the best performance whereas those housed in pens with platform exhibited the worst.  相似文献   

5.
The aim of the present work was to study the effect of dietary supplementation of Euphorbia heterophylla on the quality of the Guinea pig meat. Forty guinea pigs were divided into two groups fed ad libitum during 46 days a Panicum maximum diet (Panicum diet) or a mixed diet (75% Panicum maximum + 25% Euphorbia heterophylla) (Paneuphorbia diet) to compare their effects on performances and on the composition of guinea pig tissues and carcass. Daily weight gain, liver weight, carcass yield, and the lipid content of both the carcass and the perirenal fat were significantly increased by the Paneuphorbia diet. Feeding Paneuphorbia diet increased (P < 0.05) the n-3 PUFA content in perirenal fat, muscle, liver and in the carcass and decreased (P < 0.05) the n-6/n-3 ratios in all these tissues and the carcass. In conclusion, this study shows that Euphorbia heterophylla is a source of n-3 fatty acids which can improve significantly the n-3 PUFA content of Guinea pig meat and carcass.  相似文献   

6.
Warner–Bratzler shear force values from 560 mixed breed heifers and steers were used to determine estimates of genetic selection. Cattle were marketed from 2008 to 2011, and included five feedlot based research projects at the North Dakota State University-Carrington Research Extension Center. Samples were collected for IGENITY® analysis providing information that included selection indices and estimated breeding values for carcass traits. DNA-based test results were compared with actual carcass measurements. Marbling accounted for over 10% of the variation in WBSF while hot carcass weight was the second most influential carcass trait accounting for 4% (P < 0.01). Regression coefficients of IGENITY® molecular breeding value on phenotype for WBSF, marbling, ribeye area, yield grade, and fat thickness were low (R2 = 0.14, 0.02, 0.03, 0.03, and 0.02, respectively). Therefore selecting cattle for a higher degree of marbling and feeding a diet that meets or exceeds recommended nutrients for growth are the most important factors influencing beef tenderness and acceptability.  相似文献   

7.
Very long chain n-3 fatty acids such as eicosapentaenoic acid (EPA; 20:5n-3) are important in human cardiac health and the prevention of chronic diseases, but food sources are limited. Stearidonic acid (SDA; 18:4n-3) is an n-3 fatty acid that humans are able to convert to EPA. In utilizing SDA-enhanced soybean oil (SBO) derived from genetically modified soybeans, our objectives were to examine the potential to increase the n-3 fatty acid content of milk fat and to determine the efficiency of SDA uptake from the digestive tract and transfer to milk fat. Three multiparous, rumen-fistulated Holstein cows were assigned randomly in a 3 × 3 Latin square design to the following treatments: 1) control (no oil infusion); 2) abomasal infusion of SDA-enhanced SBO (SDA-abo); and 3) ruminal infusion of SDA-enhanced SBO (SDA-rum). The SDA-enhanced SBO contained 27.1% SDA, 10.4% α-linolenic acid, and 7.2% γ-linolenic acid. Oil infusions provided 57 g/d of SDA with equal amounts of oil infused into either the rumen or abomasum at 6-h intervals over a 7-d infusion period. Cow numbers were limited and no treatment differences were detected for DMI or milk production (22.9 ± 0.5 kg/d and 32.3 ± 0.9 kg/d, respectively; least squares means ± SE), milk protein percentage and yield (3.24 ± 0.04% and 1.03 ± 0.02 kg/d), or lactose percentage and yield (4.88 ± 0.05% and 1.55 ± 0.05 kg/d). Treatment also had no effect on milk fat yield (1.36 ± 0.03 kg/d), but milk fat percentage was lower for the SDA-rum treatment (4.04 ± 0.04% vs. 4.30 ± 0.04% for control and 4.41 ± 0.05% for SDA-abo). The SDA-abo treatment increased n-3 fatty acids to 3.9% of total milk fatty acids, a value more than 5-fold greater than that for the control. Expressed as a percentage of total milk fatty acids, values (least squares means ± SE) for the SDA-abo treatment were 1.55 ± 0.03% for α-linolenic acid (18:3n-3), 1.86 ± 0.02 for SDA, 0.23 ± <0.01 for eicosatetraenoic acid (20:4n-3), and 0.18 ± 0.01 for EPA. Transfer efficiency of SDA to milk fat represented 39.3% (range = 36.8 to 41.9%) of the abomasally infused SDA and 47.3% (range = 45.0 to 49.6%) when the n-3 fatty acids downstream from SDA were included. In contrast, transfer of ruminally infused SDA to milk fat averaged only 1.7% (range = 1.3 to 2.1%), indicating extensive rumen biohydrogenation. Overall, results demonstrate the potential to use SDA-enhanced SBO from genetically modified soybeans combined with proper ruminal protection to achieve impressive increases in the milk fat content of SDA and other n-3 fatty acids that are beneficial for human health.  相似文献   

8.
Bos indicus bulls 20 months of age grazed on pasture in Minas Gerais, Brazil either received 2 doses of the GnRF vaccine Bopriva at d0 and d91 (group IC, n = 144) or were surgically castrated on d91 (group SC, n = 144). Slaughter on d280, was 27 weeks after castration. Adverse safety issues in 8% of group SC bulls following surgery contrasted with 0% in group IC bulls. At d105 testosterone levels were suppressed to similar levels in both groups. Importantly, group IC bulls had higher live weight, hot carcass weight, ADG (P < 0.005) and dressing percentage (P < 0.0001) compared to group SC animals. There were no negative effects on carcass or meat quality traits, thus immunocastration was concluded to offer a safe and effective method that provides production gains, and improves animal welfare in Bos indicus beef bulls without impacting meat and carcass quality.  相似文献   

9.
It is necessary to identify traits that are simple to measure and correlated with milk yield to select ewes for dairying from existing populations of sheep in Australia. We studied 217 primiparous and 113 multiparous (second parity, n = 51; third parity, n = 40; and fourth parity, n = 22) East Friesian crossbred ewes, for 2 consecutive lactations, that were milked by machine following a period of suckling (24 to 28 d). We measured lamb growth, milk production, milk yield, and residual milk during early lactation (<d 60 of lactation) to test whether milk production during the suckling period or the growth rate of the lamb predicts milk yield. Milk production at weaning, or the amount of residual milk, or both, predict milk yield within lactations. These measures also predict milk yield between lactations. Lambs were weighed at birth and weaning and milk production in ewes was measured using a 4-h milk production test at d 5 of lactation and at weaning. Following weaning, ewes were milked twice daily and milk yield was recorded weekly for 8 wk and once a month thereafter. Milk production (using a 16-h milk production test) and residual milk were measured at weaning, and again 1 wk and 4 wk later. Milk yield to 120 d was correlated (r2 = 0.39) between lactations, and 120-d milk yield (primiparous 82.7 ± 2.0 L; multiparous 107.1 ± 4.2 L; second lactation 146 ± 3.7 L) can be predicted after 4 wk of machine milking using a single measurement of either daily milk yield (primiparous 770 ± 25 mL/d; multiparous 940 ± 44 mL/d; second lactation 1,372 ± 46 mL/d, r2 = 0.60 to 0.65) or daily milk production (primiparous 1,197 ± 27 mL/d; multiparous 1,396 ± 62 mL/d; second lactation 1,707 ± 45 mL/d, r2 = 0.50 to 0.53). Residual milk in primiparous ewes (38%) and multiparous ewes (34%) was high (292 ± 11 and 321 ± 20 mL, respectively) in the first lactation, but lower (17%) in the second lactation (238 ± 17 mL). Residual milk and 120-d milk yield were not correlated in either lactation and we suggest that the transfer of milk from the alveoli to the cistern between each milking may be an important mechanism that maintains milk yield in these ewes.  相似文献   

10.
The growth and breed-related changes of rib and rump characteristics in lean beef cattle and the ability of ultrasound to predict carcass traits were investigated. Three hundred bulls from three breeds were scanned monthly (6–7 times) using real-time ultrasound with final scans taken < 7 days prior to harvest. The rib and rump ultrasound measurements, except intramuscular fat content, increased (P < 0.05) with live weight. Breed affected most of traits. The 12th rib ultrasound measurements showed a weak to high positive correlation (0.131 to 0.976, P > 0.05 to P < 0.001) with 12th rib measurements in the carcass. Regression equations developed with the ultrasound measurements, explained 97% of the variation in longissimus muscle area, 88% of the variation in fat thickness and 57% of the variation in intramuscular fat content. When last ultrasound scan measurements were excluded from prediction equations, the R2 significantly decreased. Ultrasound measures “in vivo” are viable options for assessing carcass attributes of lean cattle.  相似文献   

11.
Trans fatty acids (FA) arise in ruminant-derived foods as a consequence of rumen biohydrogenation and are of interest because of their biological effects and potential role in chronic human diseases. Our objective was to compare 2 trans FA, elaidic acid (EA; trans-9 18:1) and vaccenic acid (VA; trans-11 18:1), with oleic acid (OA; cis-9 18:1) relative to plasma lipid transport and mammary utilization for milk fat synthesis. Three ruminally cannulated, Holstein dairy cows, 259 ± 6 DIM (mean ± SEM), were randomly assigned in a 3 × 3 Latin square design. Treatments were a 4-d abomasal infusion of 1) OA (45.5 g/d), 2) EA (41.7 g/d), and 3) VA (41.4 g/d). Milk samples were collected at each milking and blood samples were collected at the start and end of each treatment period. The proportions of total plasma FA associated with each plasma lipid fraction at baseline (pretreatment) were 62.6 ± 0.6% phospholipids, 26.1 ± 0.6% cholesterol esters, 9.8 ± 0.4% triglycerides, and 1.5 ± 0.1% nonesterified fatty acids; these values were unaffected by treatment. There were striking differences in the FA composition of the individual plasma lipid fractions and in the distribution of specific 18-carbon FA among the lipid fractions. Infusion of treatment isomers caused their specific increase in the various plasma lipid fractions but had no effect on milk production variables, including milk fat yield and content. Transfer efficiency of infused OA, EA, and VA to milk fat averaged 65.5 ± 3.0%, 59.7 ± 1.5%, and 54.3 ± 0.6%, respectively. For the VA infusion, 24.6 ± 1.1% of the transfer was accounted for by the increased yield of cis-9, trans-11 conjugated linoleic acid in milk fat, consistent with its endogenous synthesis from VA via the mammary enzyme Δ9-desaturase. Notably, linoleic acid (18:2n-6) and linolenic acid (18:3n-3) accounted for 47.7% of total plasma FA, but only 2.6% of FA in milk. Overall, results demonstrate clear differences in plasma transport and mammary uptake and utilization of 18-carbon FA, and these relate to the location, orientation, and number of double bonds.  相似文献   

12.
Additive genetic Angus-Brahman differences, heterosis effects, and least squares means for six carcass and six meat palatability traits were estimated using data from 1367 steers from the Angus-Brahman multibreed herd of the University of Florida collected from 1989 to 2009. Brahman carcasses had higher dressing percent (P < 0.0001), lower marbling (P < 0.0001), smaller ribeye area (P < 0.0001), and less fat over the ribeye (P < 0.0001) than Angus carcasses. Brahman beef was less tender (P < 0.0001), had more connective tissue (P < 0.0001), and it was less juicy (P < 0.001) than Angus beef. Heterosis increased hot carcass weight (P < 0.0001), dressing percent (P < 0.017), ribeye area (P < 0.0001), fat over the ribeye (P < 0.0001), and kidney, pelvic, and heart fat (P < 0.01) in Angus-Brahman crossbred steers. Results indicated that crossbred animals with up to 50% Brahman showed limited negative impact on meat quality while maximizing meat yield due to heterosis.  相似文献   

13.
The aim of this study was to investigate the association and expression of HNF1A gene as a candidate gene for meat and carcass quality traits in pigs. Statistical analysis revealed that the g.8260 A>G polymorphism significantly associated with pH 24H, meat percentage and muscle area in the F2 Duroc × Pietrain (DuPi, n = 313) and with pH 24L, fat area and backfat thickness in the Pietrain (Pi, n = 110) population. HNF1A mRNA and protein expressions were higher (p < 0.05) in animals with the low post-mortem muscle pH 24L. The promoter methylation profiling suggested that methylation was not involved on HNF1A expression regulation (p > 0.05) in animal with divergent muscle pH. In conclusion, polymorphism in porcine HNF1A gene could be used as a candidate marker to improve the meat and carcass quality traits, with the consideration of breed-specific effect.  相似文献   

14.
Thirty non-castrated male lambs with 20 ± 2.3 kg average body weight (BW) were randomly assigned to five treatments consisted of different dietary concentrations of crude glycerin (CG; 0, 3, 6, 9 and 12% on DM basis) to evaluate the effects on performance, carcass and meat quality traits. A quadratic effect was observed for performance (P = 0.04), final BW (P < 0.01) and hot carcass weight (P < 0.01). No effects of CG were observed (P > 0.05) on carcass pH neither on shear-force, cooking loss and ether extract content in longissimus. The inclusion of CG tended to reduce the Zn content in meat (P = 0.09). The data suggests that CG (36.2% of glycerol and 46.5% of crude fat) may be used in diets of finishing lambs with concentrations up to 3% without negative effects on performance and main carcass traits. Moreover, inclusion of CG seems to not affect quality and safety of meat for human consumption.  相似文献   

15.
An extracellular lipase derived from Bacillus circulans, isolated from marine macroalga, Turbinaraia conoides, was used to prepare n-3 polyunsaturated fatty acid (PUFA) concentrates from sardine oil triglycerides. The enzyme was purified 132-fold with specific activity of 386 LU/mg. The purified lipase was able to enrich sardine oil with 37.7 ± 1.98% 20:5n-3 and 5.11 ± 0.14% 18:3n-3 in the triglyceride fraction after 3 h of hydrolysis. Lower hydrophobic constants of n-3 fatty acids (18:3n-3logP = 5.65; 20:5n-3logP = 5.85, respectively) than n-6 (20:4n-6logP = 6.16) resulted in higher hydrolytic resistance of the former toward lipase, leading to their enrichment in the triglyceride fraction. Lipase-catalysed hydrolysis of sardine oil for 3 h, followed by urea complexation, provided free fatty acids containing 51.3 ± 4.65% 20:5n-3. The purified methyl ester of 20:5n-3 (68.29 ± 2.15%) from the urea concentrate was attained by chromatography on argentated neutral alumina.  相似文献   

16.
TRIB3 plays an important role in energy metabolism. This work aimed to study the porcine tribbles homolog 3 (TRIB3) gene and to evaluate its association with meat quality and carcass traits in pigs. By sequencing a portion of the porcine TRIB3 gene two single nucleotide polymorphisms (SNPs) in the first coding exon (one synonymous SNP: c.132 T > C; and one missense mutation: c.146C > T, p.P49L) were identified. The two polymorphisms were in complete linkage disequilibrium. In silico analysis of the p.P49L mutation suggested that it could have functional effects. Association studies in four groups of pigs (651 animals in total) indicated that this gene marker was associated with back fat thickness in Italian Large White and Italian Duroc pigs in two different experimental designs (P < 0.1 and P < 0.05). This polymorphism tended to be associated with lactate content of the semimembranosus muscle (P < 0.1). Among several other tissues, TRIB3 is expressed in fat and skeletal muscle.  相似文献   

17.
The aim of this study was to determine the prevalence, antimicrobial resistance and molecular epidemiology of Campylobacter coli isolated from swine in China. A total of 190 C. coli isolates obtained from two slaughter houses and ten conventional pig farms in Shandong (SD, n = 95) and Ningxia (NX, n = 95) provinces were tested for their susceptibility to 14 antimicrobials. A high prevalence (> 95%) of ciprofloxacin and tetracycline-resistant strains was observed in both SD and NX. The erythromycin and clindamycin resistance rates of C. coli from NX (ERY: 54.7% CLI: 43.2%) were higher than those from SD (ERY: 37.9%, CLI: 35.8%). A significant difference (P < 0.05) was observed in erythromycin resistance rate, but not (P > 0.05) in clindamycin resistance rate. while the resistance rates of ampicillin and kanamycin in NX (AMP: 34.7%, KAN: 43.2%) were significantly lower (P < 0.05) than those in SD (AMP: 51.6%, KAN: 71.6%). None of the tested isolates were resistant to phenicols. The majority of the isolates from both provinces (SD: 80% and NX: 73.7%) showed multi-drug resistance profiles. The point mutations of A2075G in the 23S rRNA and C257T in the gyrA gene were detected in 98% (87/89) of macrolide resistant isolates and all ciprofloxacin resistant isolates, respectively. In addition, all tetracycline-resistant isolates harbored the tet(O) gene. The high prevalence of antimicrobial resistance in C. coli strains derived from pigs in China was observed and was likely due to the extensive use of various antimicrobials. Prudent use of antimicrobial agents on farms should be further emphasized to control the dissemination of antimicrobial resistant C. coli.  相似文献   

18.
Milk minerals are important for calf growth, and they have other roles as well, such as immune regulation. This 2-yr study examined content of Ca, P, Mg, Na, K, Fe, and Zn in milk of 54 Iberian red deer hinds through 18 wk of lactation. Mean mineral composition of fresh milk was ash = 1.168 ± 0.007%, Ca = 2,330 ± 20 mg/kg, P = 640 ± 10 mg/kg, K = 1,100 ± 10 mg/kg, Na = 385 ± 3 mg/kg, Mg = 138 ± 1 mg/kg, Zn = 12.5 ± 0.2 mg/kg, and Fe = 0.65 ± 0.03 mg/kg. All minerals except Mg varied by week of lactation, but variation was usually <10% except for Fe (83% variation) and Zn (30% variation); both of those minerals increased as lactation proceeded. Increased concentrations of Fe and Zn in later lactation compensated for the reduction in milk production in mid and late lactation such that daily production was less variable for Fe (55% variation) or Zn (79% variation) than for other minerals (118 to 135% variation). Potassium content of milk decreased across time, but that effect occurred primarily during the last few weeks of lactation. Calving later vs. early in the calving season had variable effects on concentrations of different minerals: P, Mg, and K concentrations were not affected; Ca, Mg, and Na were all lower in milk from later calving hinds; and both Fe and Zn had higher concentrations in milk from hinds that calved later in the season. Lactating hinds seem to maintain a more stable daily yield of the microminerals Fe and Zn in milk compared with more variable concentrations of macrominerals as lactation progresses. Because of the essential role of Fe and Zn in immune function, a more stable supply of those minerals might be important to the health of growing red deer calves.  相似文献   

19.
The effects of dietary supplementation in pigs with plant extract (PE) from Lippia spp., titrated in verbascoside (5 mg/kg feed), from weaning to slaughter (166 days), on carcass characteristics, meat quality, collagen characteristics, oxidative stability and sensory attributes of Longissimus dorsi (LD) muscle were examined. Ten pigs per treatment were slaughter at a live weight of 109.5 ± 1.4 kg. No influence on carcass characteristics, LD meat quality parameters and collagen characteristics were observed. Dietary PE increased (P < 0.001) α-tocopherol levels in LD muscle. Raw LD of pig fed PE showed lower (P < 0.001) lipid oxidation levels than controls. A reduction (P = 0.05) of fat odor and rancid flavor intensity in cooked LD muscle stored at 4 °C for 24 h was observed in the treated group. This study shows that PE is an effective antioxidant in pork meat, enhancing oxidative status and sensory attributes, without affecting other meat quality parameters.  相似文献   

20.
The influence of dietary lecithin at doses of 0, 4, 20 or 80 g/kg fed to finisher gilts for six weeks prior to slaughter on growth performance, carcass quality and pork quality was investigated. M. longissimus lumborum (loin) was removed from 36 pig carcasses at 24 h post-mortem for Warner–Bratzler shear force, compression, collagen content and colour analyses. Dietary lecithin increased dressing percentage (P = 0.009). Pork chewiness and collagen content were decreased by dietary lecithin (P < 0.05, respectively), suggesting that improved chewiness may be due to decreased collagen content. However, dietary lecithin had no effect on shear force, cohesiveness or hardness (P > 0.05, respectively). Dietary lecithin reduced loin muscle L* values and increased a* values (P < 0.05, respectively) but no changes on b* values (P = 0.56). The data showed that dietary lecithin improved dressing percentage and resulted in less chewy and less pale pork.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号