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BACKGROUND: The aim of this study was to evaluate the effect of dietary lycopene powder on meat quality and the oxidative stability of lipid and protein of longissimus thoracis (LT) in lamb. A total of 30 male lambs were randomly sampled from three feeding groups (control without lycopene supplement, 200 and 400 mg kg−1 lycopene powder respectively) after 3 months of feeding. The muscle samples were taken after slaughter and stored at 4 °C for 7 days. RESULTS: Compared with the control, the results showed that supplementation with lycopene powder gave a higher a* value (redness), and increased the levels of vitamin A and vitamin E. Increasing dietary lycopene powder resulted in a lower degree of lipid and protein oxidation, as evidenced by lower contents of thiobarbituric acid‐reactive substance and carbonyl compounds, and higher levels of sulfhydryl groups. CONCLUSION: Dietary lycopene powder is an effective antioxidant that blocks the oxidation of meat proteins and lipids, and has a positive effect on increasing lamb meat quality during storage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This review aims to summarize the relevant published information about the effects of extensive feeding systems on the carcass and meat quality characteristics of lambs. Lambs finished in a feedlot or with supplementation under extensive systems exhibit faster growth rates, achieve target weights quicker, and produce heavier carcass weights when compared to grazing lambs. However, the literature also shows that finishing lambs on high-quality pasture can produce satisfactory growth rates without compromising carcass and meat quality traits. Lately, the consumer demand for products perceived as 'healthy' and that are produced where animal welfare is optimal under systems which do not impact negatively on the environment, has heightened the interest in lamb production under extensive systems. Lambs raised on pasture can meet many of these specifications. Also, lambs fed higher quality green pasture can produce meat with greater amounts of health-claimable omega-3 fatty acids such as eicosapentaenoic acid plus docosahexaenoic acid than feeding systems based on feedlot pellets, grain, or dry pasture/straw. It is apparent that in some previous published research, the number of animals allocated for each treatment, and the lack of replicates, makes it difficult to formulate a correct understanding of the effect of forages on lamb carcass and meat quality. Future research should concentrate on the effect of legume, improved pasture, and specialized forage finishing systems on growth rate, carcass traits, and nutritional value of meat using well-designed experiments with an adequate number of lambs and appropriate paddock replicates per treatment. [ABSTRACT FROM AUTHOR]

• Including alfalfa forage with cereal forage diets increases dietary Ca, Mg and Na • In all treatments, plasma Mg, Na, K and P decreased throughout the study, but Ca increased • Supplementation with Na and Mg is required, including when alfalfa is provided. The development of perennial wheat is proposed to increase resource-use efficiency and sustainability of crop production. Annual dual-purpose winter wheat and perennial wheat offer grazing potential, however they both have mineral imbalances due to excess forage K and deficient Na, which may lead to metabolic diseases such as hypocalcaemia and hypomagnesaemia. Notwithstanding a low forage Na concentration, it was hypothesised that the addition of forage lucerne (alfalfa), high in forage Ca and Mg, may overcome calcium and magnesium deficiencies of the wheat varieties. A pen feeding study was conducted using 10-month-old Poll Dorset × Merino ewe lambs (46.4 ± 1.8 kg) to test the effect on plasma and urine mineral status with the addition of lucerne to perennial wheat or annual wheat forage. The lambs (n = 48) were individually fed one of four diets, including perennial wheat (PW), annual wheat (W), perennial wheat + lucerne (alfalfa) (PW + L) or annual wheat + lucerne (W + L) and feed intake was calculated daily. Individual blood and urine sampling commenced on entry to the pens and were repeated at 7-day intervals for 3 further weeks. The addition of lucerne increased the dietary supply of Ca, Mg and Na and decreased K and P. When compared to W, PW offered more Ca, Mg, K, and less Na and P. There were mineral intake differences over time (P < 0.001) for all minerals. All diets offered high dietary cation anion difference (45.0 – 94.9), K: (Na + Mg) (7.3 – 12.8), K: Na (305 – 1137) ratios, while the addition of lucerne increased the Ca: P ratio and improved the K: (Mg + Ca) (Tetany index). Plasma Mg, Na, K and P declined significantly throughout the study, under all diets, to varying degrees. In Week 1, plasma Mg was significantly lower in PW lambs when compared to all other diets, but no further diet effects were observed thereafter. By contrast, plasma Ca increased throughout the study, but without dietary effects. The urinary excretion of Mg was higher with the addition of lucerne in the PW + L and W + L diets after 1-week, although this effect declined in subsequent weeks. The excretion of Ca, Na and P was very low in urine and decreased, while K excretion increased during the study. Taken together the results indicate that the greater dietary intake of Ca, Mg and Na due to the addition of lucerne was insufficient to overcome the primary mineral imbalance of high dietary K and low Na in the cereal forages. Furthermore, the addition of lucerne to the diet further decreased P intake and greatly increased the Ca: P ratio. Our calculations suggest lambs grazing any of the diets in the present study still required supplementation with Na and Mg, but the addition of lucerne alleviated the need for Ca supplementation. The need for supplementation with a source of dietary P requires further investigation. [ABSTRACT FROM AUTHOR]

Medium voltage electrical stimulation and wet ageing periods effects on the carcasses and meat quality of Australian rangeland goats were investigated. 64 rangeland goats were slaughtered as 2 equal consignments, wherein half were exposed to post-dressing electrical stimulation (300 V, 500 ms pulse width, 45 s) and half were not (control). Carcass and pH decline parameters and glycogen concentration were recorded. At 24 h post-mortem , fresh colour was measured and longissimus lumborum muscles (LL) removed. Within carcass, paired LL were halved and allocated to each of 4 ageing periods (1, 2, 4, or 21 d). There were no significant effects from electric stimulation on LL pH at 18 °C, LL temperature at pH 6, LL pH at 24 h post-mortem , semitendinosus pH at 24 h post-mortem , and LL glycogen concentration. There were no significant interactions between stimulation and ageing period on cooking loss, particle size, purge loss, sarcomere length, shear force, and ultimate pH. Independent to stimulation, shear force, particle size, and cooking values declined as ageing period increased. Purge loss was highest after 21 d of ageing. Colour stability was unaffected by ageing, although all CIE colour coordinates varied across the 74 h total retail display period. There were negative linear relationships found between LL glycogen concentrations and LL temperature at pH 6, ultimate pH, and sarcomere length. These findings suggest there to be little benefit to post-dressing electrical stimulation of rangeland goat carcasses, when applied independent to or in combination with ageing. [ABSTRACT FROM AUTHOR]