Traceability of lamb production systems: carotenoids in plasma and adipose tissue

Twenty Gascon young bulls that had been reared either in intensive conditions (INT) (n = 10) with early weaning at 3 to 4 months, or in a traditional extensive (EXT) system (n = 10) with weaning at 7 months, were subjected to the same conditions during the 145-day finishing period. Production system before the finishing period did not affect conformation, dressing percentage or morphology of the carcass; nevertheless, tissue composition differed somewhat between the two groups. Display had a stronger effect on meat colour than did production system. Percentage of myoglobin was highest in INT (P ⩽ 0.001), although meat texture and sensory quality did not differ between rearing conditions. EXT animals had darker, more yellow fat, a higher percentage of n-3 fatty acids (P ⩽ 0.001), a lower percentage of saturated fatty acids (P ⩽ 0.05) and a lower n-6/n-3 index (P ⩽ 0.001) than did the INT-reared animals. Production system before the fattening period might modify some of the characteristics of commercial beef, especially those associated with fat.Keywords: Gascon breed, beef cattle, colour, panel test, fatty acids ImplicationsThe effect of background before the entrance in a feedlot on meat quality in beef has been hardly studied for the literature available on this topic is very scarce, especially when the productive life of the animals is considered as a whole and animals are fed a common finishing diet. Our results show new information and complement the existent helping to understand the possible influence of the previous fattening production system, as grazing at an early stage provokes certain distinctive characteristics that are kept even after several months of concentrate feeding.

Section: Animalsmentioning

confidence: 99%

Effect of production system before the finishing period on carcass, meat and fat qualities of beef

Guerrero

Albertı́

Ripoll

et al. 2013

“…Fat colour values were recorded from three locations randomly selected avoiding blood dots, air bubbles and less covered areas. The proportion of reflected light each 10 nm between 450 and 510 nm in subcutaneous fat was collected and the absolute value of the integral of the translated reflectance spectrum (SUM) was calculated according to Prache and Theriez (1999), who proposed the use of SUM as an estimator of fat carotenoid pigment content. The reflectance spectrum was translated to make reflectance value at 510 nm equal zero (TR).…”

Section: Measurementsmentioning

confidence: 99%

Grazing lucerne as fattening management for young bulls: technical and economic performance and diet authentication

Alibés

Joy

Ripoll

et al. 2011

Three fattening systems were evaluated from weaning to slaughter in order to find alternatives to grain feeding in young bulls, and to test the reliability of carcass subcutaneous fat colour to discriminate among them. After weaning (224 kg), one group of animals was fed concentrates and straw until they reached the target slaughter weight (450 kg; Feedlot), another group grazed rotationally on lucerne supplemented with 1.8 kg DM/day barley until slaughter (LUC), and the third group had the same management as LUC animals for 3 months (period 1) and thereafter was finished on concentrates and straw until slaughter (period 2; LUC + Feedlot). Animals were weighed weekly and sampled monthly for serum IGF-I and leptin, and plasma non-esterified fatty acids and carotenoid pigment concentration analyses. Carcass characteristics and subcutaneous fat colour were recorded after slaughter. In period 1, Feedlot animals had slightly greater weight gains than their grazing counterparts (P< 0.10), and at the end of period 1 they had 66% greater IGF-I and 35% greater leptin concentration (P< 0.01). Plasma carotenoid pigments were undetectable in Feedlot animals, but increased during grazing in LUC and LUC + Feedlot treatments. In period 2, weight gains were lowest for LUC, intermediate for Feedlot and greatest for LUC + Feedlot animals (P< 0.001), conditioning the time taken to reach slaughter weight (73, 58 and 47 days, respectively;P< 0.05). Leptin and IGF-I concentrations increased in all management systems during period 2. Plasma carotenoid pigment concentration reached its maximum at the end of period 2 in LUC animals, but it decreased sharply in LUC + Feedlot animals in this period. Management did not affect carcass traits except for subcutaneous fat colour. Yellowness, Chroma (C*) and the value of the integral of the translated reflectance spectrum (SUM), estimator of carotenoid pigment content in fat, were higher in LUC than in LUC + Feedlot and Feedlot animals (P< 0.001). Two logistic regressions were obtained to discriminate carcasses from LUC treatment: P (LUC) = (1 + e18.8–5.6 × lightness–36.9 × redness + 0.3 × SUM + 29.8 × C*)−1and LUC + Feedlot treatment: P (LUC + Feedlot)=(1 + e833.7–11.8 × lightness + 4.7 × redness + 0.2 × SUM−2.5 × C*)−1. The economic margin, calculated as income achieved minus costs, was greatest for LUC, intermediate for LUC + Feedlot and lowest for Feedlot treatment. Therefore, grazing lucerne supplemented with barley was an interesting alternative for fattening young bulls in these conditions, producing carcasses of similar quality, which could be accurately traced by measuring subcutaneous fat colour.

“…Furthermore, consumers are demanding clear information on the food supplied to animals and increasingly focusing on the 'green image' of animal products (Prache and Thé riez, 1999). It is therefore important to be able to discriminate between products obtained through different production systems, in particular, pasture feeding v. stall feeding.…”

Section: Introductionmentioning

confidence: 99%

Methodological developments in the use of visible reflectance spectroscopy for discriminating pasture-fed from concentrate-fed lamb carcasses

Dian

Andueza

Barbosa

et al. 2007

Self Cite

The ability to authenticate the feed given to animals from the animal products has become a major challenge for scientists, monitoring bodies and commercial entities alike. This study compared two methods based on the use of the visible reflectance spectrum of the fat to discriminate pasture-fed (P) from stall concentrate-fed (S) lamb carcasses. A total of 307 (143 P and 164 S) Limousine lambs were used over 2 years. Pasture-fed lambs grazed a permanent pasture that was maintained at a leafy, green vegetative stage, and offered ad libitum; they received no supplementation at pasture. Body weight of P lambs when turning out to pasture and at slaughter averaged 9.2 (standard deviation (s.d.) 2.21) kg and 33.2 (s.d. 2.89) kg, respectively. S lambs were fed indoors on an ad libitum diet of commercial concentrate and hay until slaughter at a mean body weight of 33.7 (s.d. 3.62) kg. The reflectance spectrum of perirenal and subcutaneous caudal fat was measured at slaughter and at 24 h post mortem. Plasma carotenoid concentration was measured at slaughter. In method 1, the fat reflectance spectrum data were used at wavelengths between 450 and 510 nm to calculate an index quantifying light absorption by carotenoid pigments. In method 2, a multivariate analysis was performed over the full set of fat reflectance data at wavelengths between 400 and 700 nm. Method 2 yielded a higher proportion of correctly classified lambs compared with method 1 (P , 0.05 to 0.001), except for measurements made at 24 h post mortem on perirenal fat for S lambs. The proportion of lambs correctly classified using method 2 was 87.4% and 92.9% for measurements made on perirenal and caudal fat at slaughter, and 93.9% and 91.0% for measurements made on perirenal and caudal fat 24 h post mortem. Plasma carotenoid concentrations were higher in P lambs than in S lambs (P , 0.001), which led to correct classification of 90.7% of the lambs.