Intramuscular Collagen Properties Research Articles

Performance and meat quality traits of slow-growing chickens stimulated in ovo with galactooligosaccharides and exposed to heat stress

In vivo performance, carcass and meat quality traits of slow-growing chickens stimulated in ovo with trans galactooligosaccharides (GOS) and exposed to heat stress were evaluated. On d 12 of egg incubation, 3,000 fertilized eggs (Hubbard JA57) were divided into prebiotic group (GOS) injected with 3.5 mg GOS/egg, saline group (S) injected with physiological saline (only to assess the hatchability rate) and an uninjected control group (C). After hatching, 600 male chicks (300 from GOS and 300 from C) were housed on floor pens (6 pens/treatment, 25 birds/pen) and reared under neutral (TN) or heat stress conditions (HS, 30°C from 36 to 50 d). BW, daily feed intake (DFI), daily weight gain (DWG), feed conversion rate (FCR), and mortality were measured. At 50 d of age, 15 randomly selected birds/treatment/environmental conditions were slaughtered and the pectoral muscle (PM) was collected for analyses. Hatchability was similar among groups. BW of the newly hatched chicks was lower (P < 0.01) in GOS compared to C. Final BW, DWG, DFI, and FCR were not affected (P > 0.05) by GOS. HS reduced final BW (−12.93%, P < 0.001). During finisher phase, DFI and DWG were lower (P < 0.001) and FCR was higher (P < 0.01) in HS compared to TN. Mortality was not affected (P > 0.05) by GOS and HS. Meat from GOS chickens had a higher (P < 0.01) pH and was darker (P < 0.05) compared to C. Proximate composition, cholesterol content, fatty acid profile, and intramuscular collagen properties of PM were not affected by GOS. The HS group showed a lower (P < 0.05) content of both collagen and monounsaturated fatty acids than TN group. Significant interactions between GOS and temperature were found for FA composition. In conclusion, the differences in performance have had an impact on the responses to HS in Hubbard chickens, but not on mortality rate. GOS did not relieve the negative effect of HS on chickens’ performance.

Effect of galactooligosaccharides delivered in ovo on meat quality traits of broiler chickens exposed to heat stress

A study was carried out to evaluate meat quality traits in fast-growing chickens stimulated in ovo with trans-galactoolighosaccarides (GOS) and exposed to heat stress. On day 12 of egg incubation, 3,000 fertilized eggs (Ross 308) were divided into prebiotic group (GOS) injected with 3.5 mg GOS/egg, saline group (S) injected with physiological saline, and control group (C) uninjected. After hatching, 900 male chicks (300 chicks/treatment) were reared in floor pens in either thermoneutral (TN; 6 pens/group, 25 birds/pen) or heat stress conditions (HS, 30°C from 32 to 42 D; 6 pens/group, 25 birds/pen). At 42 D of age, 15 randomly chosen birds/treatment/temperature were slaughtered and the pectoral muscle (PM) was removed for analyses. Data were analyzed by GLM in a 3 × 2 factorial design. In ovo treatment had no effect on PM weight, pH, water-holding capacity, and shear force. GOS and S birds had lighter (L*, P < 0.01) PM than C group, whereas the latter showed a higher (P < 0.05) yellowness index (b*) compared to S group. Proximate composition, cholesterol, and intramuscular collagen properties were not affected by treatment. As for fatty acid composition, only total polyunsaturated fatty acids (PUFA) content and n-6 PUFA were slightly lower in GOS group compared to S. Heat stress had a detrimental effect on PM weight (P < 0.01) and increased meat pH (P < 0.01). PM from HS chickens was darker with a higher b* index (P < 0.05) and had a higher (P < 0.01) lipid content and a lower (P < 0.05) total collagen amount. Total saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and PUFA were similar among groups. Significant interactions between factors were found for fatty acid composition: GOS decreased (P < 0.01) SFA and increased (P < 0.05) MUFA contents in HS birds. In conclusion, in ovo injection of GOS could mitigate the detrimental effect of heat stress on some meat quality traits.

Comparison of 2 commercial turkey hybrids: productivity, occurrence of breast myopathies, and meat quality properties

This study was undertaken to compare productive performance, occurrence of breast myopathies, chemical composition, and technological properties of the meat in 2 dominant commercial turkey hybrids. A total of 972 1-day-old male turkey poults (equally divided in hybrid A and B) were randomly distributed in 18 floor pens. Overall, productive performance resulted similar between the genotypes, although they showed different growth profile (turkeys from group B grew up faster up to 84 d). Regarding the occurrence of myopathies, the percentage of breasts affected by white striping was markedly higher in both genotypes (46 vs. 60% of severe lesions, respectively for A and B; P < 0.05), while the occurrence of spaghetti meat-like condition was negligible. The histological features of the different categories of meat abnormalities resulted similar to those previously described for chicken hybrids. The technological traits such as ultimate pH, lightness, redness, marinade uptake, cooking losses, and shear force were not significantly affected by the genotype. However, turkeys from group B exhibited lower yellowness (b*, 0.50 vs. 1.04; P < 0.05) and higher drip losses (1.34 vs. 1.26%; P < 0.05). The shelf-life test on thigh meat showed no significant changes in meat color over the storage time in both hybrids, whereas thigh meat from group A showed absolute lower values of lightness (L*) and yellowness (b*) (P < 0.05). Lipid oxidation of thigh meat significantly increased during storage, although no significant difference was found between the hybrids. Proximate composition and intramuscular collagen properties resulted similar between genetic lines with the exception of total fat content (1.55 vs. 1.21%, respectively for A and B; P < 0.05). The genotype had a moderate effect on fatty acid families of breast meat as only monounsaturated fatty acid content was significantly affected (31.7 vs. 29.8%, respectively for A and B). In conclusion, the overall productive traits of commercial turkeys, including the occurrence of muscle myopathies, as well as quality attributes of fresh and refrigerated meat were only slightly affected by the genotype.

Effect of in ovo administration of different synbiotics on carcass and meat quality traits in broiler chickens

The aim of this study was to examine the effect of in ovo synbiotic administration on slaughter performance and meat quality traits of broiler chickens. On day 12 of incubation, 5,850 eggs (Cobb 500 FF) were randomly divided into 3 experimental groups and automatically injected in ovo with physiological saline (control, C) and 2 different synbiotic formulations (SYN1: Lactobacillus salivarius + galactooligosaccharides; SYN2: Lactobacillus plantarum + raffinose family oligosaccharides). After hatching, 240 males were randomly chosen (80 chicks per group) and split into 8 replicate pens (10 birds per pen). At 42 d of age, 15 birds per treatment were weighed and slaughtered. In ovo synbiotic administration had a low effect on investigated traits, but depends on the kind of synbiotic administered. Both synbiotic formulations did not affect final BW, weight, and yield of carcass and pectoral muscle (PM); likewise, physicochemical properties (pH, color, water holding capacity), intramuscular collagen properties, and cholesterol content of PM were not affected by treatment. Synbiotic administration reduced (P = 0.061) the lipid content compared with C group, markedly (P < 0.05) with synbiotic SYN2. Meat from SYN1 birds displayed a higher (P < 0.01) content of saturated fatty acids (SFA), lower monounsaturated fatty acids (P < 0.05 compared only to SYN2), and lower (P < 0.01 and P < 0.05) polyunsaturated fatty acids (PUFA), n-6 PUFA and n-3 PUFA compared to C and SYN2 groups. The ratio of n-6 to n-3 PUFA was affected by the synbiotic administration (P = 0.039). Meat from C and SYN2 groups displayed a higher (P < 0.01) ratio of PUFA to SFA and lower (P < 0.01) atherogenic and thrombogenic indices compared to SYN1. In conclusion, this study has shown that in ovo administration of synbiotics did not negatively affect slaughter performance and physicochemical properties of meat. However, meat from C and SYN2 birds showed a preferable fatty acid profile, with a positive effect on nutritional properties of chicken meat.

Effects of age and season of slaughter on meat production of light lambs: Carcass characteristics and meat quality of Leccese breed

The effects of the slaughter season (winter and spring) and the age at slaughter (45 and 60 days) on the carcass characteristics and physico-chemical quality of meat were investigated on 40 Leccese lambs. In each season, 20 lambs were subdivided into two groups corresponding to the experimental ages. All lambs received maternal milk and a supplementation of hay and commercial concentrate from 30 days to slaughter. The ewes were fed a basal mixed diet (unifeed) and commercial concentrate and were allowed to graze for 5h a day on polyphytic cultivated grassland. The increase of the lambs’ slaughter age from 45 to 60 days resulted in an improvement in live weight, some commercial cuts (shoulder and loin), the majority of the carcass measurements, adiposity and conformation of shoulder and leg and the muscle/fat ratio. Intramuscular collagen properties were also affected by slaughter age. Considering the slaughter seasons, the best results have been obtained in spring and have been maximised in lambs slaughtered at 60 days that showed the greatest live weight (16kg), good percentages of commercial cuts and carcass measurements, the greater levels of adiposity and better conformations of shoulder and leg and the lowest Warner–Bratzler (WB) shear force, without substantial difference in relation to colorimetric indices of meat. In conclusion, age and season of slaughter should be considered for the traditional production of light lambs. Lambs slaughtered in spring at 60 days of age showed the better characteristics of the carcasses and quality of meat.

Influence of in ovo prebiotic and synbiotic administration on meat quality of broiler chickens

A trial was conducted to evaluate the effect of in ovo injection of prebiotic and synbiotics on growth performance, meat quality traits (cholesterol content, intramuscular collagen properties, fiber measurements), and the presence of histopathological changes in the pectoral muscle (PS) of broiler chickens. On d 12 of incubation, 480 eggs were randomly divided into 5 experimental groups treated with different bioactives, in ovo injected: C, control with physiological saline; T1 with 1.9 mg of raffinose family oligosaccharides; T2 and T3 with 1.9 mg of raffinose family oligosaccharides enriched with different probiotic bacteria, specifically 1,000 cfu of Lactococcus lactis ssp. lactis SL1 and Lactococcus lactis ssp. cremoris IBB SC1, respectively; T4 with commercially available synbiotic Duolac, containing 500 cfu of both Lactobacillus acidophilus and Streptococcus faecium with the addition of lactose (0.001 mg/embryo). Among the hatched chickens, 60 males were randomly chosen (12 birds for each group) and were grown to 42 d in collective cages (n = 3 birds in each 4 cages: replications for experimental groups). Broilers were fed ad libitum commercial diets according to age. In ovo prebiotic and synbiotic administration had a low effect on investigated traits, but depend on the kind of bioactives administered. Commercial synbiotic treatment (T4) reduced carcass yield percentage, and the feed conversion ratio was higher in T3 and T4 groups compared with other groups. The abdominal fat, the ultimate pH, and cholesterol of the PS were not affected by treatment. Broiler chickens of the treated groups with both slightly greater PS and fiber diameter had a significantly lower amount of collagen. The greater thickness of muscle fibers (not significant) and the lower fiber density (statistically significant), observed in treated birds in comparison with those of the C group, are not associated with histopathological changes in the PS of broilers. The incidence of histopathological changes in broiler chickens from examined groups was low, which did not affect the deterioration of meat quality obtained from these birds.

Cholesterol content and intramuscular collagen properties of pectoralis superficialis muscle of quail from different genetic groups

To study growth performance and meat quality traits (cholesterol content and intramuscular collagen properties) of quail, 3 trials were carried out. Trial 1 used males of generation 19 of the egg type Japanese quail (Coturnix japonica) selected previously (until generation 17) for low (n = 8) or high (n = 7) yolk cholesterol content as well as an unselected control (n = 11). Trial 2 used males of meat Pharaoh quail selected earlier (generations 1 to 6 and 9 to 11) on the basis of BW decrease after periodic deprivation of food (high decrease of weight, n = 10; low decrease of weight, n = 8) and unselected control (n = 10). Trial 3 compared males of English White quail, Manchurian Golden quail, and British Range quail. The birds were raised to 35 d of age. Quail were fed ad libitum commercial diets according to age and had free access to water. At slaughter, all birds were individually weighed (after a fasting period of 12 h), stunned, and decapitated. After the refrigeration period (24 h at 4°C), the left pectoralis superficialis muscle was removed from the carcasses, weighed, vacuum packaged, and stored frozen (-40°C) for analyses of cholesterol and intramuscular collagen (IMC; collagen and crosslink concentration). In trial 1, divergent selection for yolk cholesterol content did not significantly influence pectoralis superficialis muscle weight and IMC crosslinking of Japanese quail, whereas it significantly reduced growth and IMC amount. In addition, it had greater effect on the amount of cholesterol in meat; in fact, the meat of quail with low yolk cholesterol content contained lower cholesterol (-36.6%) than that of birds with high yolk cholesterol content. In trial 2, divergent selection on the basis of Pharaoh quail BW decrease altered IMC crosslinking, leading to variability in meat tenderness of Pharaoh quail. In trial 3, English White quail were significantly heavier than the other breeds.

Effects of rearing system and genotype on intramuscular collagen properties of pigs

In the past few years there has been an increasing interest in animal products originating from rearing systems that could be considered ‘natural’ or ‘traditional’, and niche market opportunities are available for pork produced with socially-acceptable assurances. Nevertheless, research comparing the effects of housing systems (outdoors vs indoors) on pork tenderness has yielded conflicting results, perhaps due to geographical location, climate and genotypes evaluated (Beattie et al., 2000; Gentry et al., 2001; Guy and Edwards, 2001)...

Effects of selection for yolk cholesterol on growth and meat quality in Japanese quail (Coturnix coturnix japonica)

Descendants () of S18 generation of Japanese quails (Coturnix coturnix japonica), selected for low (line 11, n=15) or for high (line 12, n=6) yolk cholesterol content were used for this experiment. The high (12) and low (11) lines were developed from a control egg type (line13) wild color plumage stock 07, from Poultry Breeding Station in Ivanka at Danube (Slovakia) that was maintained without conscious selection. The results of selected lines were compared to this one from unselected lines, egg type (line 13, n=15) and meat type (line 8, n=15), to study productive performance (growth and carcass weight) as well as meat quality traits (intramuscular collagen properties, fatty and cholesterol content). The birds were grown up to 35 days of age. Quails were fed ad libitum with commercial diets according to their ages. Animals had free access to water during the experiment. The body weight of the quails was controlled every week (from week 1 to 5). At the slaughter (at avg. weight of 104.0, 107.7, 110.6 g vs 209.3 g for lines 11, 12, 13 vs 8, respectively; P<0.05) the hot carcass weight was recorded and dressing percentage was calculated. Pectoralis superficialis muscles were removed from the carcasses to assess intramuscular collagen (IMC) properties (collagen and crosslink concentrations), intramuscular lipid and cholesterol contents. Growth and slaughter performance, intramuscular fat percentage and IMC properties of Pectoralis superficialis were not different between the birds selected for low (line 11) and high (line 12) yolk cholesterol content and were also found to be similar between the quails of egg type and those selected for yolk cholesterol content (lines 11 and 12). Compared to the birds of egg type line and those selected for yolk cholesterol content, the quails of meat type had higher growth and carcass traits (P<0.05), while meat quality traits were found to be similar. The meat of the quails selected for low cholesterol in the egg yolk (line 11) had lower (P<0.05) cholesterol (-35.9%) than that of the birds characterized by high cholesterol in the egg yolk (line 12). In conclusion, divergent selection for yolk cholesterol content did not significantly influence growth and slaughter traits, intramuscular fat and IMC properties of Japanese quail, while it affected the amount of cholesterol in meat. The quails of meat type showed the highest growth and slaughter traits.

Acceptability and intramuscular collagen properties of Podolian beef as affected by ageing

The present study aimed to assess the effect of different ageing periods (2, 8, 15 and 21 d) on intramuscular collagen (IMC) properties, meat colour and water holding capacity (WHC) and on meat liking in order to define the appropriate maturation length for Podolian meat. Longissimus dorsi lumborum from 6 Podolian young bulls, slaughtered at 14 months of age, was used. A total of 101 consumers participated in the test. Although not significantly, IMC concentration decreased after 15 d of ageing. Fibre collagen stability had a wavering trend, with an increase at 15 d (P<@0.05) and a significant decrease at 21 d (P<0.05). Ageing time influenced colour parameters, with increased L* (P<0.01), a* (P<0.05) and b* (P<0.001). The degradation of myofibrils with muscle maturation decreased the percentage of thawing loss (P<0.01). The application of a prolonged ageing (15-21 d) improved the overall liking (P<0.001) and the liking in terms of odour (P<0.001), taste/flavour (P<0.001) and texture (P<0.001). No significant differences were observed between 15 and 21 d of ageing for these parameters. We conclude that for Podolian meat the most appropriate ageing period may be 15 days.

The effect of dietary energy and vitamin E administration on performance and intramuscular collagen properties of lambs

The effect of different dietary energy levels, with or without injections of vitamin E, on growth, carcass traits and intramuscular collagen (IMC) characteristics of growing lambs was studied. Twenty-four Ile de France ram lambs were evaluated in a 2 × 2 factorial design involving different DL-α-tocopheryl acetate injections (C, control = 0 and V = 150 IU/wk, i.m. for eight wk) and energy level (N, normal = 7.61 and L, low = 6.47 MJ/kg DM). Growth and slaughter performance, and IMC characteristics were not influenced by diet. DL-α-tocopheryl acetate increased ADG during suckling, while it did not affect live weight, carcass weight and dressing percentage. Vitamin E injections reduced carcass shrinkage but also had a negative effect on pelvic limb percentage. The Longissimus muscle pH values were higher in V than in C lambs. DL-α-tocopheryl acetate reduced IMC maturity and muscle hydroxylysylpyridinoline crosslink concentration, more markedly in lambs fed low energy diets.

Characteristics of intramuscular collagen in two sheep breeds

Abstract The Texel breed, new to New Zealand, gives superior meat production, particularly from the more valuable hindquarter. This study examines the intramuscular collagen properties in Texel x Romney and Romney x Romney lambs. Collagen is responsible for the so‐called background toughness in meat. High‐quality meat cuts often contain low concentrations of collagen which is relatively soluble when heated. Therefore, the intramuscular collagen characteristics of the two groups were compared as one aspect of meat tenderness. The Texel‐sired lambs grew more rapidly but the difference was not significant. Texel muscle weights were heavier at each of three slaughter ages (100, 150, and 215 days) for two hindquarter muscles, semimembranosus (P < 0.05) and biceps femoris (P < 0.01). The forequarter muscle (supraspinatus) was statistically unaffected by breed. As expected there was a marked decrease in collagen solubility with age for both muscles (P < 0.001), but little effect on concentration. Collagen concen...