Design of digital games in health sciences education

No Abstrac

Effect of dietary vitamin D3 supplementation on meat quality of naked neck chickens

Consumers’ interest of indigenous chicken meat is increasing. An experiment was conducted to determine the effect of vitamin D3 supplementation on meat quality of indigenous male naked neck chickens. Different supplementation levels of 0, 2000, 4000, 6000 and 8000 IU of vitamin D3 per kg DM of feed were used. 13 weeks old male naked neck chickens with a mean live weight of 1200 ± 3 g were supplemented with vitamin  D3 for a period of seven days before slaughter. A 2 (cooking or not) x 2 (postmortem agings of 0 or 24 hs) x 5 (vitamin D3 levels) factorial arrangement in a complete randomized design was used for shear force analysis of raw or cooked naked neck chicken meat. A 2 (postmortem agings of 0 or 24 hs) x 5 (vitamin D3 levels) factorial arrangement in a complete randomized design was used for sensory evaluation of the meat. A quadratic equation was used to determine vitamin D3 supplementation levels for optimum shear force value and sensory attributes. Vitamin D3 supplementation did not improve (P>0.05) shear force values of unaged or aged raw and cooked naked neck chicken meat. Shear force values of unaged raw or cooked meat were optimized at different levels of 3735 (r2=0.832) and 2512 (r2=0.669) IU of vitamin D3 per kg DM feed, respectively. Shear force values of aged raw or cooked meat were optimized at different levels of 6728 (r2 =0.274) and 4249 (r2=0.873) IU of vitamin D3 per kg DM feed, respectively. Vitamin D3 supplementation had no effect (P>0.05) on unaged meat tenderness, juiciness and flavour. However, vitamin D3 supplementation improved (P<0.05) aged meat tenderness and flavour. Tenderness, juiciness and flavour of aged naked neck chicken meat were optimized at supplementation level of 6830 (r2=0.839), 6894 (r2=0.683) and 9795 (r2=0.657) IU of vitamin  D3 per kg DM. It was concluded that vitamin D3 supplementation improved tenderness and flavour of aged naked neck chicken meat. However, shear force values of unaged or aged raw or cooked naked neck chicken meat were not improved by vitamin D3 supplementation.Keywords: Shear force, postmortem aging, calpains, connective tissue, tenderness, juiciness, flavorAfrican Journal of Biotechnology Vol. 12(22), pp. 3576-358

Blood profiles of indigenous Pedi goats fed varying levels of Vachellia karroo leaf meal in Setaria verticillata hay-based diet

Vachellia karroo (Acacia karroo) is promising fodder for goats in the critical dry season in communal rangelands. The only limitation to the use of this fodder tree is the presence of phenolic compounds, such as condensed tannins. A study was conducted to investigate the effects of tanniniferous V. karroo leaf meal feeding on blood profiles of indigenous Pedi goats fed a basal diet of Setaria verticillata grass hay. Twenty indigenous Pedi goats, weighing 18 ± 2 kg, were allocated in a completely randomized design to five dietary treatments containing V. karroo leaf meal at 20% (S80A20), 25% (S75A25), 30% (S70A30), 40% (S60A40) and 50% (S50A50) of the total diet in a 22-day trial. Twelve ml of blood were collected from the jugular vein from each goat before and after the experiment for haematological and serum biochemical assays. Daily dry matter intake (DMI) was similar across treatments, ranging from 633 g to 765 g per goat per day. There was no difference in initial and final bodyweights of goats consuming various experimental diets. However, bodyweight gains were significantly higher in goats fed a diet with 50% leaf meal as compared with other treatment groups. There were no differences in haematological indices of Pedi goats except for mean corpuscular haemoglobin (Hb) concentration. Goats fed 50% leaf meal had significantly lower mean corpuscular haemoglobin concentration (MCHC) values as compared with other treatment groups. Similarly, there were no differences in the blood serum chemistry of goats that consumed various inclusion levels of V. karroo, except for serum total protein (TP) and alanine aminotransferase (ALT). Goats fed 50% leaf meal had depressed serum TP, while serum enzyme Alanine aminotransferase (ALT) concentration decreased significantly in goats fed 25% leaf meal as compared with those on the 20% dietary treatment. Tannin concentration of 8.2 g/kg dry matter (DM) had no toxic effect on experimental animals. A 40 % inclusion of V. karroo in a Setaria verticillata hay-based diet may be fed to indigenous Pedi goats without compromising the immunity system and health of the animals.Keywords: Condensed tannin, fodder, haematology, seru

Influence of low-tannin sorghum on performance and bone morphometrics of male Ross 308 broilers aged 1 - 42 days

The objective of this study was to determine the effects of low tannin sorghum as a maize replacement on the performance and bone morphometrics of Ross 308 broiler chickens. A total of 250 one-day-old broiler chickens were allotted to a complete randomized design with five treatments replicated five times. Birds were offered varying sorghum levels as maize replacement at 0% (control), 25%, 50%, 75% and 100%, formulated to be isonutritive and isoenergetic. The condensed tannin and total phenolic contents of the sorghum were analysed. Bodyweight and feed intake were measured weekly to calculate feed conversion ratio (FCR), and mortality was recorded as it occurred. Digestibility measurements were done when the chickens were between 15 and 21 days and between 35 and 42 days old. At ages 21 and 42 days, two chickens per pen were slaughtered to determine bone characteristics. A digital calliper was used to measure the length and diameter of the bones, and an electronic scale was used to determine the weight of the bones. Ash, calcium and phosphorus concentrations of the bones were determined. The Seedor and robusticity indices of the tibia were also calculated. The general linear model procedure of Statistical Analysis Software was used to analyse the data. At 1 - 21 days old bodyweight was higher for birds fed a level of 50% sorghum than those that were offered the control diet. Replacing maize with sorghum improved the metabolizable energy (ME) of broiler chickens aged 42 days. Bodyweight and FCR of birds fed diets with 50%, 75% and 100% sorghum were higher and better, respectively, than those on diets with 25% and 0% sorghum at 22 - 42 days old. Bone morphometries of chickens aged 1 - 21 days and 22 - 42 days were not affected by replacing maize with sorghum. Thus, maize can be replaced by a low tannin white sorghum without causing adverse effects on chickens.Keywords: minerals, tibia bone, Seedor and robusticity indice

Paediatric radiology seen from Africa. Part I: providing diagnostic imaging to a young population

Article approval pendingPaediatric radiology requires dedicated equipment, specific precautions related to ionising radiation, and specialist knowledge. Developing countries face difficulties in providing adequate imaging services for children. In many African countries, children represent an increasing proportion of the population, and additional challenges follow from extreme living conditions, poverty, lack of parental care, and exposure to tuberculosis, HIV, pneumonia, diarrhoea and violent trauma. Imaging plays a critical role in the treatment of these children, but is expensive and difficult to provide. The World Health Organisation initiatives, of which the World Health Imaging System for Radiography (WHIS-RAD) unit is one result, needs to expand into other areas such as the provision of maintenance servicing. New initiatives by groups such as Rotary and the World Health Imaging Alliance to install WHIS-RAD units in developing countries and provide digital solutions, need support. Paediatric radiologists are needed to offer their services for reporting, consultation and quality assurance for free by way of teleradiology. Societies for paediatric radiology are needed to focus on providing a volunteer teleradiology reporting group, information on child safety for basic imaging, guidelines for investigations specific to the disease spectrum, and solutions for optimising imaging in children

An ecological perspective on children’s play with digital technologies in South Africa and the United Kingdom

This paper reports a mixed-methods study of the play of children (3–11) with digital technologies in South Africa (SA) and the United Kingdom (UK), discussing the interrelatedness of access to devices and the Internet, contextual realities, and adult-child relations. An adapted ecological model [Bronfenbrenner (1979) The ecology of human development: Experiments by nature and design. Harvard University Press] guided analysis. Parents and carers in the UK were more likely than their SA counterparts to report children's engagement in object, construction and transgressive digital play, correlating with access differences, especially to tablet devices. However, play incorporating technologies was extensive, even in contexts in SA with limited access to a wide range of devices or readily available internet. Despite relying primarily on smartphones, children in SA were more likely to create digital content unassisted than those in the UK. The qualitative data complicate understandings of particular play types, including transgressive digital play

Dietary energy level for optimum productivity and carcass characteristics of indigenous Venda chickens raised in closed confinement

A study was conducted to determine dietary energy levels for optimum productivity and carcass characteristics of indigenous Venda chickens raised in closed confinement. Four dietary treatments were considered in the first phase (1 to 7 weeks) on two hundred day-old unsexed indigenous Venda chicks indicated as EVS1, EVS2, EVS3 and EVS4 (11, 12, 13 and 14 MJ ME/kg DM, respectively) and each treatment was replicated five times. In the second phase (8 - 13 weeks), 160 indigenous Venda female chickens, aged eight weeks, were randomly allocated to four dietary treatments and each treatment was replicated five times in a completely randomized design. The diets used in both trials were isonitrogenous but with different energy levels. A quadratic equation was used to determine dietary energy levels for optimum feed intake, growth rate, FCR and ME intake at both the starter and grower phases and the carcass characteristics of the birds at 91 days. Dietary energy levels of 12.91, 12.42, 12.34 and 12.62 MJ ME/kg DM feed supported optimum feed intake, growth rate, FCR and ME intake, respectively, for the starter phase. At the grower phase, dietary energy levels of 12.56, 12.66, 12.62 and 12.71 MJ ME/kg DM feed supported optimum feed intake, growth rate, FCR and ME intake, respectively. Carcass, drumstick, thigh and wing had optimum weights at dietary energy levels of 13.81, 13.23, 13.43 and 13.18 MJ ME/ kg DM, respectively. Thus, dietary energy level for optimization depended on the particular production parameter in question.Keywords: Metabolisable energy, optimization, quadratic equation, digestibilit

Effects of egg weight on hatchability, chick hatch-weight and subsequent productivity of indigenous Venda chickens in Polokwane, South Africa

A study was conducted to determine the effect of egg weight on hatchability, chick hatch-weight, mortality and subsequent productivity of indigenous Venda chickens. Three hundred and sixty indigenous Venda chicken eggs were collected for a period of a week and selection was done based on the weight of the eggs. A complete randomized design was used, with four treatment weights, each with 90 eggs. The four treatment weights were as follows: below 49 g, between 50 and 59 g, between 60 and 69 g, and above 70 g. Egg weight was positively and strongly correlated with egg hatchability (r2 = 0.727) and chick hatch-weight (r2 = 0.953). Heavier-sized eggs hatched chicks had higher mortality rates. Growth rate and live weight of the chickens were optimized at different egg weights of 56 (r2 = 0.657) and 60 (r2 = 0.870) g, respectively, for chickens aged 1 to 7 weeks, and egg weights of 61 g (r2 = 0.514) and 60 g (r2 = 0.948), respectively, for chickens aged 8 to 13 weeks. It is concluded that indigenous Venda chicken egg weight affects hatchability, hatch-weight, mortality and subsequent productivity of the chickens. It is concluded that production variables were optimized at different egg weights. This means that the selection of eggs for incubation will depend on the parameter in question.Keywords: Venda chickens, egg weight for optimal productivity, growth, mortalit

Effects of onion extracts () inclusion in diets on growth performance, carcass characteristics, and bone morphometric of broiler chickens

Objective Animal feed companies and researchers are currently embarking on quests for feed additives that could combat the pathogens while promoting growth as well as maintaining quality products. The current study aimed to evaluate the effects of onion extracts on growth performance, carcass quality, and bone morphometrics of broiler chickens. Methods A total number of 200 one-day-old unsexed Ross 308 broiler chicks were assigned to 5 treatment groups, replicated 4 times. Each replicate (pens) held 10 chickens in a completely randomized design. The experimental diets were then randomly allotted to the pens which act as experimental units. The isoenergetic and isonitrogenous diets were formulated by including onion extracts at 0, 5, 10, 15, or 25 g/kg in a complete broiler diet. Feed intake, and body weight, were recorded then used to calculate feed conversion ratio. At the end of the experiment (42 days), four chickens from each pen were randomly selected for slaughter for carcass, bone morphology and sensory evaluation. Results Results showed that onion extract supplementation did not affect (p>0.05) growth performances and meat sensory evaluation. However, there was a significantly increased (p<0.05) meat shear force in groups receiving onion extracts dietary treatments. Furthermore, onion extracts improved (p<0.05) bone morphology of broiler chickens in terms of weight, diameter, calcium, and phosphorous contents. Conclusion In conclusion, onion extracts can be safely included in a commercial broiler diet as a growth promoter without causing adverse effects on growth performance traits and carcass quality in chickens. Onion extract supplementation improved tibia bone growth and strength in broiler chickens