With ever-increasing population of the world,
enhancement of food production is a major necessity.
Biological principles as applied to animal husbandry and
plant breeding have a major role in our efforts to increase
food production. Several new techniques like embryo
transfer technology and tissue culture techniques are going
to play a pivotal role in further enhancing food production.
9.1 ANIMAL HUSBANDRY
Animal husbandry is the agricultural practice of breeding
and raising livestock. As such it is a vital skill for farmers
and is as much science as it is art. Animal husbandry
deals with the care and breeding of livestock like buffaloes,
cows, pigs, horses, cattle, sheep, camels, goats, etc., that
are useful to humans. Extended, it includes poultry
farming and fisheries. Fisheries include rearing, catching,
selling, etc., of fish, molluscs (shell-fish) and crustaceans
(prawns, crabs, etc.). Since time immemorial, animals like
bees, silk-worm, prawns, crabs, fishes, birds, pigs, cattle,
sheep and camels have been used by humans for products
like milk, eggs, meat, wool, silk, honey, etc.
It is estimated that more then 70 per cent of the world
livestock population is in India and China. However, it is
CHAPTER 9
STRATEGIES FOR ENHANCEMENT
IN FOOD PRODUCTION
9.1 Animal Husbandry
9.2 Plant Breeding
9.3 Single Cell Proteins
9.4 Tissue Culture
2020-21
166
BIOLOGY
surprising to note that the contribution to the world farm produce is only
25 per cent, i.e., the productivity per unit is very low. Hence, in addition
to conventional practices of animal breeding and care, newer technologies
also have to be applied to achieve improvement in quality and productivity.
9.1.1 Management of Farms and Farm Animals
A professional approach to what have been traditional practices of farm
management gives the much needed boost to our food production. Let us
discuss some of the management procedures, employed in various animal
farm systems.
9.1.1.1 Dairy Farm Management
Dairying is the management of animals for milk and its products for
human consumption. Can you list the animals that you would expect
to find in a dairy? What are different kinds of products that can be
made with milk from a dairy farm? In dairy farm management, we deal
with processes and systems that increase yield and improve quality of
milk. Milk yield is primarily dependent on the quality of breeds in the
farm. Selection of good breeds having high yielding potential (under the
climatic conditions of the area), combined with resistance to diseases is
very important. For the yield potential to be realised the cattle have to be
well looked after – they have to be housed well, should have adequate
water and be maintained disease free. The feeding of cattle should be
carried out in a scientific manner – with special emphasis on the quality
and quantity of fodder. Besides, stringent cleanliness and hygiene (both
of the cattle and the handlers) are of paramount importance while milking,
storage and transport of the milk and its products. Nowadays, of course,
much of these processes have become mechanised, which reduces chance
of direct contact of the produce with the handler. Ensuring these stringent
measures would of course, require regular inspections, with proper record
keeping. It would also help to identify and rectify the problems as early
as possible. Regular visits by a veterinary doctor would be mandatory.
You would probably find it interesting if you were to prepare a
questionnaire on diverse aspects of dairy keeping and then follow it up with
a visit to a dairy farm in your locality and seek answers to the questions.
9.1.1.2 Poultry Farm Management
Poultry is the class of domesticated fowl (birds) used for food or for their
eggs. They typically include chicken and ducks, and sometimes turkey and
geese. The word poultry is often used to refer to the meat of only these birds,
but in a more general sense it may refer to the meat of other birds too.
As in dairy farming, selection of disease free and suitable breeds,
proper and safe farm conditions, proper feed and water, and hygiene and
health care are important components of poultry farm management.
2020-21
STRATEGIES FOR ENHANCEMENT IN FOOD PRODUCTION
167
You may have seen TV news or read newspaper
reports about the ‘bird flu virus’ which created a scare in
the country and drastically affected egg and chicken
consumption. Find out more about it and discuss whether
the panic reaction was justified. How can we prevent the
spread of the flu in case some chicken are infected?
9.1.2 Animal Breeding
Breeding of animals is an important aspect of animal
husbandry. Animal breeding aims at increasing the yield
of animals and improving the desirable qualities of the
produce. For what kind of characters would we breed
animals? Would the selection of characters differ with
the choice of animals?
What do we understand by the term ‘breed’? A group
of animals related by descent and similar in most characters
like general appearance, features, size, configuration, etc.,
are said to belong to a breed. Find out the names of some
common breeds of cattle and poultry in the farms of your
area.
When breeding is between animals of the same breed it
is called inbreeding, while crosses between different breeds
are called outbreeding.
Inbreeding : Inbreeding refers to the mating of more
closely related individuals within the same breed for 4-
6 generations. The breeding strategy is as follows – superior males and
superior females of the same breed are identified and mated in pairs.
The progeny obtained from such matings are evaluated and superior
males and females among them are identified for further mating. A
superior female, in the case of cattle, is the cow or buffalo that produces
more milk per lactation. On the other hand, a superior male is the bull,
which gives rise to superior progeny as compared to those of other
males.
Try to recollect the homozygous purelines developed by Mendel as
discussed in Chapter 5. A similar strategy is used for developing purelines
in cattle as was used in case of peas. Inbreeding increases homozygosity.
Thus inbreeding is necessary if we want to evolve a pureline in any animal.
Inbreeding exposes harmful recessive genes that are eliminated by selection.
It also helps in accumulation of superior genes and elimination of less
desirable genes. Therefore, this approach, where there is selection at each
step, increases the productivity of inbred population. However, continued
inbreeding, especially close inbreeding, usually reduces fertility and even
productivity. This is called inbreeding depression. Whenever this becomes
a problem, selected animals of the breeding population should be mated
Figure 9.1 Improved breed of
cattle and chickens
(a) Jersey (b) Leghorn
(a)
(b)
2020-21