Ante-and post-mortem strategies to improve the meat quality of high-value muscles harvested from farmed male common eland (Taurotragus oryx)

Effects of immunocastration and supplementary feeding level on the performance and blood biochemical markers of farmed yearling fallow deer (Dama dama)

In cervids, blood biochemical markers may reflect changes in various physiological and environmental factors, especially in response to changes in metabolism following nutrient supplementation or the manipulation of hormone production. Decreasing androgen production through immunocastration (IC) to ease the husbandry of male animals is currently a more ethically acceptable method than physical castration, but its commercial use is unexplored in fallow deer. Forty yearlings male fallow deer were grouped into four treatment combinations: IC on high (200 g commercial pellets + 600 g concentrate mixture of 90% oats and 10% wheat grains) or low (100 g commercial pellets + 300 g concentrate mixture of 90% oats and 10% wheat grains) level of feed supplementation, or noncastrated bucks on a high or low level of feed supplementation. Immunocastrated animals were vaccinated at the start of the study (Week 1) and again during Week 3 of the study. Diet affected all body growth parameters (slaughter weight, daily gain, carcass weight, dressing percentage and body condition score). Fallow deer from all treatments showed increasing concentrations of fat and energy blood biochemical markers over the study period, including plasma glucose (GLU) and triglyceride (TRIG), and decreased cholesterol (CHOL) and lipase (LIPA) concentrations. The higher level of supplementary feeding decreased plasma albumin (ALB) and creatinine (CREA), and increased globulin (GLOB) concentrations. On the other hand, IC and lower-level supplementation reduced growth performance. Overall, IC may be an interesting tool for welfare management of yearling stags for slaughter; however, the advantage appears to only be in well-fed animals, as low-level of feeding can further reduce growth performance in immunocastrated animals. Further studies should evaluate the carcass performance of animals under similar treatment conditions to ascertain the effects on muscle and fat yields.

Effects of alternating electric field during freezing and thawing on beef quality

Alternating electric field (AEF) technology was used during freezing-thawing-aging (FA) of beef aged for 0, 1, 3, 5 and 7 days. Color, lipid oxidation, purge loss, cooking loss, tenderness, and T₂ relaxation time were determined for frozen-thawed-aged beef with AEF (AEF + FA) or without AEF (FA) and compared to aged only (OA) controls. FA increased purge loss, cooking loss, shear force values and lipid oxidation (P < 0.05) but decreased a* values compared with AEF + FA treatment. It also exacerbated the spaces between muscle fibers and contributed to the transformation of immobile water to free water. AEF served to maintain meat quality by reducing purge loss, cooking loss and increasing meat tenderness and maintaining color and lipid oxidation only in steak that was frozen before aging. This most likely occurred due to AEF increasing the speed of freezing and thawing and by reducing the space between muscle fibers compared to FA alone.

South African consumerattitudesunderlyingthechoicetoconsumegamemeat

Currently little is known about the South African game meat consumer market or the underlying attributes driving the choice to consume game meat, limiting the game meat industry's market positioning, growth and ultimately its contribution to food security and economic growth. The study explored attitudes of 1081 consumers through an online survey and structural equation modelling, to determine which game meat attributes were the strongest predictors of the choice to consume game meat. Health benefits and production ethics have the strongest direct relationship with the choice to consume game meat. Availability indicated a moderate and price a weak direct relationship whereas safety had no significant relationship with the choice to consume game meat. Future game meat marketing campaigns may need to emphasise health benefits and production ethics of game meat to stimulate the consumer market in South Africa. The findings from this study will benefit the game meat industry and advance SDG 2 to improve food security and address zero hunger in South Africa. Implementing the recommendations from this study may change consumers' approach to game meat which will also bring about economic change in South Africa.

Carcass and Offal Yields of Farmed Common Eland (Taurotragus oryx) Males, as Affected by Age and Immunocastration

This study investigated the effects of immunocastration and slaughter age on the carcass yield performance of intensively farmed common eland males. Eighteen male eland (five immunocastrated juveniles, three intact juveniles, five immunocastrated sub-adults, and five intact sub-adults) were finished for four months, after which their carcass, offal, primal cut, and individual muscle yields were determined. Juveniles were ~6 months of age at the start of the experiment, while sub-adults were ~1.5 years old. Primal cuts were dissected to determine the percentage yields of meat, bones (with tendons), separable fat, and trimmings. Immunocastration had no effect on offal or carcass yields. While sub-adults had increased individual muscle yields, juveniles had greater proportionate yields of primal cuts and a greater total high-value: low-value meat ratio. Whilst slaughtering younger male eland could provide additional economic advantages, this should be considered being against changing marketing trends.

Carcass Yields and Physical-Chemical Meat Quality Characteristics of Namibian Red Hartebeest (Alcelaphus buselaphus) as Influenced by Sex and Muscle

This study determined the carcass yields of red hartebeest from Namibia and compared the physical-chemical meat quality characteristics of six different muscles (biceps femoris, infraspinatus, longissimus thoracis et lumborum, semimembranosus, semitendinosus, and supraspinatus) for both males and females. Red hartebeest males were heavier (133.92 kg) than females (114.20 kg) but the average dressing percentage did not differ between the two sexes. Muscles from females had a lower mean shear force value of 3.59 kg/1.27 cm ø, compared to males (4.23 kg/1.27 cm ø). The most tender muscle was the infraspinatus of the female treatment group, while the semimembranosus of the male treatment group was the least tender muscle. Drip loss, cooking loss and L* (lightness) values were not affected by sex. The largest hue angle was observed in the semitendinosus muscle of the female treatment group (28.94°), and it was thus the lightest red muscle. The highest chroma values (17.3) were observed in the semimembranosus muscle. Muscle protein content averaged 20.5% over all treatment combinations, and the mean intra-muscular fat content for both male and female muscles was low (2.4%). The shoulder muscles, infraspinatus and supraspinatus, of the females had the highest fat content (2.7%). The results indicate that red hartebeest meat should be market according to specific muscles and that sex of the animals need not be considered during marketing.

Physical Changes during Post-Mortem Ageing of High-Value Impala (Aepyceros Melampus) Steaks

Antelope meat production is rapidly growing, not only due to their adaptation to marginal land usage, but also because of its favorable nutritional properties and free-range production. However, limited information is available on the meat quality and processing potential of game meat for commercial consumption. The objective of this study was to determine the ageing period to achieve maximum tenderness of longissimus thoracis et lumborum (LTL) muscles of impala. The LTL muscles of 11 male and 11 female impala were harvested, and divided into eight portions. Each portion was randomly allocated to 1, 2, 4, 6, 8, 10, 12, or 14 days of wet-ageing (4 °C) in vacuum packaging. The meat pH, color, weep loss, cooking loss, and Warner–Bratzler shear force were measured throughout ageing. Initially the ageing profile differed depending on the sex of the animal from which the muscle was harvested; however, after 8 days of ageing, maximum tenderness was reached (13.5 ± 0.91 N) and no further sex differences were seen. Ageing improved the surface color of all meat until day 8, after which discoloration occurred. Therefore, it is recommended that impala LTL steaks should be wet-aged at 4 °C for eight days to achieve maximum tenderness and minimize sex variability.