Zahra Mohammed Hassan

Animal proteins are essential for the optimal growth and health of humans. Meat and milk are common sources of protein, mostly produced by ruminants. The agrarian challenges experienced around the world warrant sourcing alternative proteins from animals that can withstand harsh environmental conditions to produce quality proteins. Donkeys (Equus asinus) are known to survive on low husbandry and inferior quality forage to produce meat and milk, which have been used since ancient times. However, the commercialisation of these products has not flourished due to product scarcity, low production rates, and consumer preferences. Recent discoveries and the quest to look for alternative sources of protein have sparked studies on donkey products. In addition, milk and meat from donkeys have active ingredients that could also contribute to curing diseases. Donkey milk is believed to contain antioxidant, antimicrobial, antiproliferative, and antidiabetic properties. In many countries, particularly in Africa, the consumption of donkey meat and milk has not been fully adopted due to a lack of knowledge and legislation regarding production.

This study aimed at investigating the impact of early versus normal grain harvesting on the chemical composition and secondary metabolites of Amaranthus cruentus species grown in South Africa. Mature harvested grain had higher (p < 0.05) DM, CF, NDF and ADF content compared to prematurely harvested grain. There were no significant (p > 0.05) differences between CP, ADL and GE of premature and mature harvested grains. Mature harvesting resulted in higher grain Ca, P, Mg and K content. Essential amino acids spectrum and content remained similar regardless of maturity at harvest. The grains displayed an ample amount of unsaturated fatty acids; the highest percentage was linoleic acid: 38.75% and 39.74% in premature and mature grains, respectively. β-Tocotrienol was detected at 5.92 and 9.67 mg/kg in premature and mature grains, respectively. The lowest was δ-tocotrienol which was 0.01 and 0.54 mg/kg in premature and mature grains, respectively. Mature harvested grain had a higher secondary metabolite content compared to premature harvested grains. The results suggest that mature harvested Amaranthus cruentus grain contain more minerals and phytochemicals that have health benefits for human and livestock immunity and gut function, which ultimately improves performance. This study concludes that A. cruentus grown in South Africa is a potential alternative cereal to major conventional cereals.

Edible insects can be produced sustainably, with less environmental impact than other forms of livestock. Globally, over 2000 edible insect species have been reported and are regarded as a great source of nutrition, both as food and feed. Over the years, rural people have used indigenous knowledge to either store or process such insects. However, such valuable knowledge, if not properly recorded and documented, can easily be lost. Thus, there is a need to strike a balance between the use of indigenous and scientific knowledge to produce and process these delicacies. In addition, such indigenous knowledge is vital for preserving biodiversity, since insects are good indicators of climate change as it influences their development, reproduction, and survival. Therefore, successful and sustainable solutions may lie in bringing back indigenous knowledge systems.

There has been a research gap in the genetic, physiological, and nutritional aspects of indigenous chickens of Africa over the past decade. These chickens are known to be economically, socially, and culturally important to the people of Africa, especially those from marginalised communities. Although they are associated with poor productivity in terms of the number of eggs laid, most consumers prefer their flavoursome meat. Several local chickens have been classified into breeds or ecotypes, but many remain unidentified and are facing extinction. To prevent this, the Food and Agriculture Organization has launched an indigenous poultry conservation programme. In addition, the Agricultural Research Council in South Africa has established a programme to protect four local chicken breeds. The purpose of this review is to provide a detailed understanding of the description, uses and conservation methods of local chicken breeds of Africa. Several studies have been conducted on the nutritional requirements of local chickens, but the results were inconclusive and contradictory. This review concludes that local chickens play a significant role in improving livelihoods, and strategies to preserve and sustain them must be intensified.

Over recent years, the monogastric animal industry has witnessed an increase in feed prices due to several factors, and this trend is likely to continue. The hike in feed prices is mostly due to extreme competition over commonly used conventional ingredients. For this trend to be subdued, alternative ingredients of both plant and animal origin need to be sourced. These types of ingredients are investigated with the aim of substituting all or some of the conventional compounds. However, alternative ingredients often have a double-edged sword effect, in that they can supply animals with the necessary nutrients although they contain antinutritional factors such as tannins. Tannins are complex secondary metabolites commonly present in the plant kingdom, known to bind with protein and make it unavailable; however, recently they have been proven to have the potential to replace conventional ingredients, in addition to their health benefits, particularly the control of zoonotic pathogens such as Salmonella. Thus, the purpose of this review is to (1) classify the types of tannins present in alternative feed ingredients, and (2) outline the effects and benefits of tannins in monogastric animals. Several processing methods have been reported to reduce tannins in diets for monogastric animals; furthermore, these need to be cost-effective. It can thus be concluded that the level of inclusion of tannins in diets will depend on the type of ingredient and the animal species.

Phenolic compounds that are present in amaranth crops have gained a lot of interest from researchers due to their health benefits potential. Therefore, the aim of this study was to investigate phenolic compounds present in different plant parts of Amaranthuscruentus using liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry. Moreover, data were analyzed by one-way analysis of variance of the statistical analysis software, whereas commercial statistical package version 4.02 was used for principal component analysis. A total of 21 phenolic compounds were detected and eight were not identified. Caffeoylsaccharic acid isomer, coumaoryl saccharic acid, tryptophan, feruloyl-d-saccharic acid isomer a, b, and c, caffeoyl isocitrate, quercetin 3-O-rhamnosyl-rhamnosyl-glucoside, feruloyl isocitrate, hyperoside, kaempferol rutinoside, and alkaloid compounds were mostly detected in tender and mature leaves. Generally, rutin content was higher (p < 0.05) in most vegetative parts of the amaranth plant, thus, late maturity leaves, tender leaves, and mature leaves, respectively. Lower quantities of rutin were observed in tender grains, flowers, and mature grains. It can be concluded that amaranth contains phenolic compounds, predominantly in the vegetative parts, which makes it to be a promising source of phenolic compounds beneficial to human health.

Over the years the growth and health of food-producing animals have been enhanced by the use of antibiotics. These have helped reduce on-farm mortalities, lower incidences of diseases and more importantly improve productivity. Generally, the utilization of antibiotics in feed has been reevaluated since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. Multiple countries have introduced bans or severe restrictions on the non-therapeutic use of antibiotics. This has therefore warranted the urgent need for alternatives. Africa is facing its own challenges as it has been reported to be one of the continents with the highest number of foodborne diseases with approximately 91 million related diseases and 137,000 death per annum. Stakeholder and policy direction has been put in place to curb this escalation; however, the problem persists. The use of alternatives has been recommended and some successfully used in other countries as well as Africa, including pro- and prebiotics and phytochemicals. This then leads to the core aim of this review which is to (1) determine the extent to which antimicrobial-resistant pathogens have affected Africa, (2) assess the current measures put in place by Africa to reduces antimicrobial resistance and finally (3) explore the alternative use of antibiotics in poultry production. Improved sanitary conditions and farm biosecurity are important alternatives that could be adopted by farmers instead of depending on antibiotic drugs for disease control and prevention.

Millet grains are rich in phenolic compounds which have health benefits. This study aims to elucidate the phenolic properties of pearl and finger millet grown in South Africa and Zimbabwe. The milled samples were analyzed by Waters Synapt G2 Quadrupole time‐of‐flight (QTOF) mass spectrometer (MS). A total of eight phenolic compounds were detected and quantified in the millet varieties, which included derivatives of benzoic acid such as protocatechuic and p‐hydroxybenzoic acids. Flavonoids such as catechin, epicatechin, procyanidin B1, procyanidin B2, and kaempferol glycoside were also detected. Generally, catechin was the dominant phenolic compound, followed by epicatechin. The mean values for catechin ranged from 2.50 to 12.6 mg/kg for the pearl millet and 610.4 to 675.1 mg/kg for the finger millet. While the epicatechin mean values ranged between 1.2 to 1.8 for pearl millet and 99.1 to 139.5 for finger millet. Procyanidins B1 and B2 were only detected and quantified in the finger millet types, While Kaempferol glycoside was only recorded in the pearl millets with mean values of 196.0 mg/kg for pearl millet South Africa and 213.6 mg/kg for pearl millet Zimbabwe. There was a difference among the varieties for the content of kaempferol glycoside. Protocatechuic and p‐hydroxybenzoic acids were only present in the finger millet types, their mean values were (20.9, 23.7 mg/kg) and (16.8,13.5 mg/kg) respectively. It can be substantiated from the outcome of this study that millet can be used as a source of valuable phenolic compounds and that the variety of millet is the determining factor of the phenolic compound content.

Millets which are considered the third most important cereal in Africa have remained underutilised for food and feed. Therefore, the core aim of this study was to evaluate types of millets obtained from South Africa and Zimbabwe for physical and chemical characterization. Catechin and epicatechin were higher for finger millet types. Crude protein and gross energy were similar for all the millets. However, the starch content of the South African finger millet was higher compared to the Zimbabwean type and the pearl millets from both regions. The macro-minerals of the four millets varied with calcium and magnesium being higher in finger millets. All the millet types had abundant potassium which ranged from 3864.60 to 4899.30 mg/kg. Furthermore, the essential amino acids of the millet types differed greatly. Overall, a greater impact on physical and chemical characteristics was influenced by millet type, even though some locational differences were observed.