Scale Effects between Body Size and Limb Design in Quadrupedal Mammals

Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties – limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency – were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass0.40); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass1.0), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry.</p

The efficiency of probiotics administrated via different routes and doses in enhancing production performance, meat quality, gut morphology, and microbial profile of broiler chickens

CITATION: Soumeh, E. A. et al. 2021. The efficiency of probiotics administrated via different routes and doses in enhancing production performance, meat quality, gut morphology, and microbial profile of broiler chickens. Animals, 11:3607, doi:10.3390/ani11123607.The original publication is available at https://www.mdpi.comTo study the efficiency of Bacillus spp. probiotics administered via different routes and doses, a 6-week grow-out trial was conducted using a total of 378 day-old mixed-sex ROSS308 broiler chickens in a completely randomized block design. Six experimental diets included probiotics added at two different inclusion rates into the feed (250 g/ton; PRO250, or 500 g/ton; PRO500), or in the drinking water (25 g/L; PRO-WS), or as a feed synbiotic (250 g probiotic + 250 g/ton prebiotic; SYN), compared to a negative (NC; without additives) and positive control (PC; with antibiotics) diets. The PRO-WS enhanced feed intake (p < 0.05) and tended to improve average daily gain and final body weight (p = 0.14). Broiler gut morphology in the duodenum including the villus height (p = 0.04), villus width (p = 0.05) and crypt depth (p = 0.02) were improved by PRO500. Firmicutes was the most abundant phylum, followed by Bacteroidetes. Streptococcaceae, Lachnoospiraceae, Peptostreptococcaceae, Ruminococcaceae, and Erysipe-lotrichaceae were the top five most abundant families. Antibiotic inclusion in PC reduced microbial beta-diversity and increased similarity compared to probiotic inclusion (p = 0.05). Probiotic inclusion reduced the relative abundance of Bacteroides fragilis, which is a commonly isolated pathogen and is considered as a marker for antimicrobial resistance. Overall, probiotic supplementation via feed or water may potentially improve the production performance of the broiler chickens, and water-soluble probiotics are potentially more effective. Probiotics, especially when added to water, suggest a promising feed additive to support gut microbial maturation and diversity, and may reduce resistant bacteria in broiler chickens. However, it is suggested that the best route for the administration of probiotics be further examined under commercial conditions to find the most effective and practical application method that yields the most consistent results.https://www.mdpi.com/2076-2615/11/12/3607Publisher's versio

Profile of Back Bacon Produced From the Common Warthog

The common warthog (Phacochoerus africanus) has historically been hunted and consumed by rural communities throughout its distribution range in Africa. This study aims to develop a processed product from warthog meat in the form of back bacon (Longissimus thoracis et lumborum) as a healthy alternative meat product and to determine its chemical and sensory characteristics derived from adult and juvenile boars and sows. The highest scored attributes included typical bacon and smoky aroma and flavor, and salty flavor, as well as tenderness and juiciness. Neither sex nor age influenced the bacon&rsquo;s chemical composition; the bacon was high in protein (~29%) and low in total fat (&lt;2%). Palmitic (C16:0), stearic (C18:0), linoleic (C18:2&omega;6), oleic (C18:1&omega;9c), and arachidonic (C20:4&omega;6) were the dominant fatty acids. There was an interaction between sex and age for the PUFA:SFA ratio (p = 0.01). The differences between sex and age class are considered negligible regarding the overall profile and healthiness of the bacon

Exotic protein sources to meet all needs

Venison from farmed deer has by now become common on the market. This follows the application of animal husbandry techniques to ensure a controlled supply of quality meat. Numerous studies discussed in this presentation have elucidated some of the factors that influence the meat composition and quality derived from various deer species. On the other hand, meat from wild, free-roaming animals has not yet reached a similar position in the industry and in the mind of the consumer. Yet these species show great potential, especially as pertaining to their meat production when discussed under the global warming scenario. In particular, the rodent species that are currently utilized in the bushmeat trade show potential for meat production. This presentation will endeavor to discuss the positive and negative aspects of these species as potential meat sources

Genetic and nutritional influence on the total lipid fatty acid profile of Clarias gariepinus muscle

The fatty acid profile of four different genetic strains of Clarias gariepinus: gold (G), Netherlands (N), RAU (K) and Wild (W) were evaluated. Fertilised eggs and larvae of the four strains were maintained under identical environmental conditions. After nine weeks, the two faster growing strains (G and W) had less total body lipid than the others (N and R). The total saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids of the four strains were: G – 32.1; 26.8 and 37.9%; N – 33.5; 27.8 and 35.5%; R – 32.7; 29.0 and 35.4%; W – 32.9; 27.7 and 36.8%, respectively. The major fatty acids that showed statistically significant differences between strains were: C16:0, C18:1ω9, C22:5ω3 and C22:6ω3. The G strain had a significantly higher ω3/ω6 ratio (2.2) compared to that of the other strains (N – 1.9; K – 1.9 and W – 1.9). In a second trial, juveniles of strain G were fed an artificial diet for 60 days containing no lipid (A, control), or the following lipids at 10% of the diet, sunflower oil (B. a high level of C18:lω9 and C18:2ω6), cod liver oil (C, a high level of 20 and 22 Cω3 fatty acids) and tallow (D, predominantly SFA and MUFA). Muscle total lipid composition was strongly influenced by diet and contained the following SFA, MUFA and PUFA percentages, and a ω3/ω6 ratio of: A – 35.9; 45.3; 15.0% and 0.5; B – 30.6; 33.4; 33.6% and 0.1; C – 33.2; 37.2; 23.6% and 1.8; D – 38.7; 45.3; 12.1% and 0.4, respectively

Data from: Energetic benefits and adaptations in mammalian limbs: scale effects and selective pressures

Differences in limb size and shape are fundamental to mammalian morphological diversity; however, their relevance to locomotor costs has long been subject to debate. In particular, it remains unknown if scale effects in whole limb morphology could partially underlie decreasing mass-specific locomotor costs with increasing limb length. Whole fore- and hindlimb inertial properties reflecting limb size and shape – moment of inertia (MOI), mass, mass distribution, and natural frequency – were regressed against limb length for 44 species of quadrupedal mammals. Limb mass, MOI, and center of mass position are negatively allometric, having strong potential for lowering mass-specific locomotor costs in large terrestrial mammals. Negative allometry of limb MOI results in a 40% reduction in MOI relative to isometry for our largest sampled taxa. However, fitting regression residuals to adaptive diversification models reveals that co-diversification of limb mass, limb length, and body mass likely results from selection for differing locomotor modes of running, climbing, digging, and swimming. The observed allometric scaling does not result from selection for energetically beneficial whole limb morphology with increasing size. Instead, our data suggest that it is a consequence of differing morphological adaptations and body size distributions among quadrupedal mammals, highlighting the role of differing limb functions in mammalian evolution

Deceit with decapods?: evaluating labelling accuracy of crustacean products in South Africa

Despite the high value of decapod crustaceans, relatively little research has focused on assessing the transparency in the marketing of these species. This study represents the first comprehensive evaluation of the quality of labelling, and the extent of mislabelling, of decapod crustacean products on the South African market. Data collected through surveys of supermarkets and seafood shops in three provinces (KwaZulu-Natal [KZN], Western Cape [WC] and Gauteng [GP]), indicated that the large majority of domestically available crustacean products were imported, but that 18% of these failed to comply with locally applicable country of origin labelling regulations. Voluntary information relating to the scientific name, production method (wild caught or farmed), and capture method of the species was supplied more frequently in supermarkets than in seafood shops, more frequently in the WC and GP than in KZN, and more frequently on shrimp products than on crab and lobster products. DNA sequencing of 77 products collected from the surveyed outlets revealed that 24 (31%) were misrepresented in some way. Species misrepresentations were most pronounced for shrimps, with Litopenaeus vannamei and Pleoticus muelleri being confirmed as the most common substitute species. One shrimp product was found to contain at least three different species, none of which matched the declared species, whereas a product labelled as crab turned out to be a member of the phylum Mollusca rather than the subphylum Crustacea. Overall, these findings demonstrate that the misrepresentation of crustaceans is commonplace on the South African market, signalling the need for a revision of the current seafood labelling and traceability legislation, as well as monitoring and enforcement efforts

Proximate and fatty acid composition of cooked South African Cape snoek (Thyrsites atun)

CITATION: Henning, S. S. & Hoffman, L. C. 2017. Proximate and fatty acid composition of cooked South African Cape snoek (Thyrsites atun). South African Journal of Science, 113((5/6), Art. #2016-0161, doi:10.17159/sajs.2017/20160161.The original publication is available at http://sajs.co.zaCape snoek (Thyrsites atun) is an important source of protein for people in South Africa; however, nutritional information thereof is limited. The proximate and fatty acid compositions of raw and cooked (80 °C) snoek muscles were determined according to official AOAC methods. The mean moisture, ash, total lipids and protein for raw snoek were 72.8±1.86%, 1.3±0.09%, 4.0±1.16 and 21.5±1.35%, respectively. Cape snoek is very high in palmitic acid (24.65±1.43%), oleic acid (18.21±2.64%), eicosapentaenoic acid (EPA, 9.11±2.06%) and docosahexaenoic acid (DHA, 19.70±3.25%). With the exception of total lipids, cooking significantly reduced moisture (69.40±2.03%) and ash (1.12±0.12%), and increased protein (24.47±1.39%) content. It is concluded that Cape snoek is very high in protein and can be classified as a low-fat fish which is rich in EPA and DHA.https://www.sajs.co.za/article/view/3811Publisher's versio