Livestock carriage capacity and infrastructure will be needed, and new processing plants will have to be constructed. Furthermore, the additional waste( manure, slurry, gases, slaughter offal) will need to be handled in a way that optimally protects the environment( soil, water, air).
Breeding
Increased efficiency in meat production must accompany the overall rise in livestock production. In poultry, growth and feed conversion rates – being the ratio of amount of feed in kg per kg live weight( typically 1.5 to 1.8) – have already been massively improved, and this development must be pursued. For swine, there seems to be considerable potential for better performance, but progress is slower on this front. Efforts to increase productivity are ongoing in beef cattle and in dairy cows as well. Although already rather efficient, aquaculture could still increase overall performance levels by improving the esh yield in sh.
Nutrition
For maximum production efficiency nutrition, both in terms of macronutrients and of micronutrients such as vitamins, meat production needs to be optimized. High-yielding breeds are delicate hybrids, and their nutrition must be carefully balanced inorder to exploit their full genetic potential. Since supplemental vitamins, which are not instantly utilized by the metabolism, are deposited in meat, eggs or transferred into the milk, they eventually improve the nutritional value of these end-products for the consumer.
Feed utilization
To improve the sustainability of animalderived protein production, the limited resources of feedstocks must be exploited to the maximum. For this reason, feed enzymes are commonly used in monogastric animals( poultry, swine) to improve the digestibility of nutrients. Carbohydrases with different speci c activities can degrade brous material in cereals and thereby make energy available to the host which otherwise would be wasted. Proteases improve the digestibility of protein, which is the most expensive feed ingredient and of which the supply might become limited in the future. Finally, phytases release inorganic phosphorous
( P) from plant-bound phytate, which could not be utilized by monogastric animals in former times. By using such products, less non-digested potentially pollutant P is excreted by the animal.
Alternative feed ingredients
Another necessity for keeping a higher production rate sustainable is to nd alternative feed ingredients, since the production of common crops might not be increased to the necessary extent, and as the main feedstuffs( corn, cereals, soybean) compete directly with human consumption. �ere are tropical raw materials available which could serve this purpose. Besides vegetable sources of protein, insects have recently been considered as potential feed ingredients for livestock and aquaculture production. �e larvae of insects contain up to 60 % of high-quality protein and the content of indigestible chitin is lower than in the adult stage. Insects can be grown on biowaste from the food processing industry or from households, and certain species could even utilize ligno-cellulosic biomass. Insects have a more efficient feed conversion capacity than any other farmed animal, and the requirements for management and husbandry are rather low.
Longevity of high-yielding livestock animals
Under production conditions, farm animals are prone to fatal diseases of various origins. Furthermore, high productivity is rapidly exhausting the metabolic resources of long-lived animal categories( laying / breeder hens, breeding sows, dairy cows) and reduces their life expectancy. A prolongation of their lifespan would contribute substantially to an improvement of the production efficacy, with more eggs or day-old chicks, more piglets, and more milk.
�e elimination of antibiotics
A special challenge of meat production is the elimination of antibiotics from animal farming. For a long time, antibiotic growth promotors( AGPs) were added to the feed of livestock for the prevention of infectious diseases. Since certain of these products are structurally related to antibiotics used in human medicine, the considerable risk of inducing cross-resistance in life-threatening pathogens has been recognized. Consequently the prophylactic use of AGPs has been banned in Europe, but is still allowed in the rest of the world. As alternatives to AGPs so-called“ Eubiotics” – which have the ability to bene cially modulate the gut micro ora – are being developed. Pre- and probiotics, organic acids and essential oils have the potential to foster adequate gut health. Yet the therapeutic use of antibiotics for treating animal diseases is currently not under scrutiny, although the approval for certain products from human medicine has been revoked.
Environmental considerations
Facing the massive increase in demand for animal-derived food and consequently the enormous expansion of animal husbandry, the environmental emissions from this industry must be given special attention. �e rst concern should be the sustainable disposal of manure. Although animal excreta and slurry are convenient fertilizers, grasslands and croplands should not be oversupplied with nutrients which cannot be bound by the soil matrix and therefore would leak out into rivers and lakes, causing eutrophication of the water resources. Furthermore, trace elements such as zinc, copper and cobalt, which are essential for animal performance, can accumulate in the soil and thereby create damage to the growing crops. Making animal-derived protein production more efficient should result in less excreta per unit of edible product. But considering the expected expansion of production, novel concepts for processing the manure and potentially extracting valuable fractions from this material for re-use are urgently required.
Gas emissions of carbon dioxide, ammonia and methane, which contribute to the greenhouse effect and thus aggravate the global warming problem, should not be allowed to increase. For this environmental issue, a few feed additives are available on the market, but none of them currently seems sufficiently efficacious to allow anticipated levels of production growth in poultry and swine with neutral or shrinking emissions. Methane from enteric fermentation in ruminants represents the single largest source of anthropogenic origin. For this segment, a feed additive is under development which has the potential to reduce methane emissions by at least 30 %.
www. farmersreviewafrica. com January- February 2017
FARMERS
[ 49 ] REVIEW AFRICA