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The food animals

HEALTH is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.

World Health Organisation chronicle (1978)

Meat is normally regarded as the edible parts (muscle and offal) of the food animals which consume mainly grass and other arable crops, namely, cattle, sheep, goats, pigs, horses, deer, reindeer, buffalo, musk oxen, moose, caribou, yak, camel, alpaca, llama, guanaco, vicuna, etc. In addition, poultry have become a major meat-producing species, while rabbits, guinea pigs, capybara and various game animals and birds provide a substantial amount of protein, particularly in localised areas. Fish and other seafood have also been an important part of man's diet since earliest times.

Although, theoretically, hundreds of animals could supply meat for human consumption, in practice, only a relatively small number of species are used today. This is all the more remarkable since it represents in general the instruction of the Levitical law of the Old Testament, most of which is in accord with modern sanitary science. The animals suitable for the food of man had to part the hoof and chew the cud. Only those fish with fins and scales were wholesome. It is true that today we eat pig, rabbit and hare, but it is recognised that they are subject to parasitic infestation. There appears to be little doubt that the dangers of trichinosis and of Cysticercus cellulosae were recognised 1400 years before the birth of Christ. In many parts of the world, horseflesh forms an important article of human diet. The Danes reintroduced the consumption of horseflesh into Europe during the siege of Copenhagen in 1807; slaughter of horses for human consumption is now well established in Denmark, Belgium, Holland and Germany.

All the above animals, including fish, are converters, that is, they utilise green vegetable material with varying efficiency to produce protein. Even micro-organisms can be classified as converters in that they use carbohydrates from plants to make protein from simple nitrogenous compounds. Especially when an animal eats something which is inedible for man or could not easily be made into food for man, it is considered valuable as a source of food; so when pigs and poultry, and even other animal species, are used as scavengers to eat scraps, by-products, etc., they are very useful indeed. However, when food which could be utilised by human beings is fed to livestock, the question of efficiency becomes more problematic. Nevertheless, other factors, such as the production of manure for fertiliser usage, variety in the human diet, etc., have to be borne in mind.

Not only did the Creator command the earth to 'bring forth grass, the herb yielding seed and the fruit tree yielding fruit after his kind' (Genesis 1:11). He also 'made the beast of the earth after his kind, and cattle after their kind, and everything that creepeth upon the earth after his kind' (Genesis 1:25). For both plant and beast, 'God saw that it was good' (Genesis 1:12 & 25). They were both to be used as food for man.

In more recent times, efforts have been made to domesticate certain wild animals, although many of these have been used as food since ancient times. In Africa and Russia, elands are being domesticated, as well as antelope in the latter country. Kangaroos are being kept for meat in Australia, and in South America, the large rodent capybara, which is a semi-aquatic vegetarian, is being used as a source of meat, although it is not especially palatable. There are probably many other wild species which could be utilised in meat production and would have some advantages over the domesticated animals since they exist on less valuable land, need only rough grazing, are more disease resistant and act as a tourist attraction. Some problems, however, arise in connection with feeding, protection from predators, slaughter and meat inspection.

Recent innovations have included the breeding of wild boar in England and buffalo in Germany, France and Poland. Wild boars introduced from Germany and Denmark into England are used to produce purebreds as well as crosses with established breeds of pigs. Differences in quality and flavour are said to exist between the wild variety and the various crosses. Litter sizes average six piglets and only one litter is produced yearly. Slaughtered at 12-14 months, wild boar has a live weight of about 59 kg and a dead weight of around 45 kg. The meat is very lean with an acceptable flavour, but stress is sometimes associated with abattoir slaughter, which may necessitate on-farm handling. In Great Britain, the keeping of wild boar is subject to the Dangerous Wild Animals Act.

Buffalo meat is said to be more tender, leaner and gamier than beef, with lower levels of cholesterol. Although expensive in France, it is cheaper than beef in Canada. The name buffalo is often applied to the bison (Bison bison) of North America, a different species of the order Bovidae. There are several species; the Indian buffalo (Bubalus bubalis), sometimes called the water buffalo or arna, is the only one to be domesticated. It is found in many parts of the Old World, with significant numbers in Hungary, Italy and France.

The future for meat and meat products will depend mainly on consumer demand and the prices at which they can be profitably produced. As living standards rise, so also does the consumption of meat. Factors such as the cost of production, feed conversion efficiency, land use and availability, consumer taste, price to consumers, diet, attitudes of people to meat production methods, use of protein from non-animal sources, etc. will all play a part in determining future demands.

Procedures such as genetic engineering, embryo transfer, sexed semen, cross-breeding and twinning will continue to be utilised in attempts to produce more productive livestock with improved milk and meat quality. But if close attention is not paid to the vital importance of disease resistance, we may well see the development of stock susceptible to existing and novel conditions, some of which may have serious public health implications. Consumer attitudes must always be borne in mind by research workers and those engaged in the agriculture and food industries, which will only prosper in a climate of real consumer confidence in the quality and safety of food.

In order to address this point, much food from animals is produced under 'Farm Quality Assured Schemes'. These provide customers with some assurance that the animals have been reared in a manner which involves animal welfare and environmental issues and are fit to produce wholesome, safe food products. This complements the 'farm-to-fork' approach to meat production with control over all the nutritional, welfare, housing and other management factors, as well as ensuring the traceability of the food product. Veterinarians have a pivotal role in this discipline, both on the farm and at the meat plant.

Dietary factors

Concern about the amount of fat, especially saturated fat, in the diet, has been given prominence in the Western world due to the adverse effects on human health. According to the Living Costs and Food Survey (2011), the amount of dietary energy derived from fat was 38.1% for UK adults, with 14.2% of this energy being from saturated fats. While these values are lower than 20-30 years ago, the amount of fat in British diets is still higher than current recommendations. The Scientific Advisory Committee on Nutrition (SACN) states that the amount of dietary energy derived from saturated fat should not exceed 11%.

Steps have been taken to have legislation which require total fat and saturated fatty acid content labelling on a wide variety of foodstuffs. While much of the intake of fat is derived from milk and dairy products, meat and meat products, margarine, cooking fat and salad oils, some comes from vegetable sources, where it is either produced in a saturated form, for example, coconut oil, or converted into such during manufacture. An increase in dietary unsaturated fatty acids has been shown to reduce the risk of cardiovascular disease (CVD) and possibly some cancers, asthma and diabetes. It is possible to modify animal diets to increase the amount of unsaturated fatty acids in meat, milk and eggs and to decrease the n-6:n-3 fatty acid ratio (Woods and Fearon, 2009).

The sources of fat in the average British diet are given in Table 1.1.

Table 1.1 Average British diet fat consumption (g/person/day) (FAOSTAT) 2009

If people respond to the SACN recommendations and there are indications that this is already the case, there will be major changes in food consumption which will inevitably have an impact on production methods in agriculture, especially in milk and...