In spite of various advances in developed countries, the traditional system
of livestock rearing in developing countries remain unchanged because of poor
socioeconomic conditions, scarcity of feed and fodder, poor production potential
of animals, poor health and managemental conditions (Krishna
et al., 1998). Due to improved breeding policy, the genetic makeup
of animals has been improved but the major constraint is shortage of good quality
of feed and fodder to meet their balanced nutritional requirements. Hence, there
is an urgent need to handle this deficiency of balanced nutrition of ruminants.
The present article is an attempt to focus the role of biotechnology in improving
the nutritional base of livestock.
In animal nutrition, the biotechnology can improve the plane of nutrition through
protection of protein, aminoacids (Walli, 2005; Yadav
and Chaudhary, 2010) and fat (Shelke et al.,
2011), use of enzymes to improve the availability of nutrients from feed
and to reduce the wastage of the feed and fodder, prebiotics and probiotics
or immune supplements to inhibit enteric pathogenic bacteria, use of plant biotechnology
to produce feed and fodder with good nutritive values can be done with ease,
addition of vaccines or antibodies in feeds can be used to protect the animals
from the disease, genetic manipulation of rumen microbes to improve the animal
PROTECTION OF PROTEIN, AMINOACIDS AND FAT
Rumen degrades the protein to form ammonia and then the ruminal microbes use
this non-proteinous nitrogen to synthesize the microbial protein. To increase
the efficient utilization of degradable protein, it should be protected from
ruminal degradation through chemical treatments such as formaldehyde and physical
treatments like heat treatment and extrusion cooking (Kumar
et al., 1994). Some researchers have reported 33% reduction in protein
degradability by formaldehyde treatment of groundnut cake. Fat can be protected
using the saponification of fat with calcium salts. Feeding Ca soaps of fatty
acids, which are inert in rumen, to negative energy balance animals enhances
dietary energy density and thus, energy intake in early without compromising
the activity of rumen microflora (Thakur and Shelke, 2010).
Thus, the deleterious effect of negative energy balance on animals can be alleviated.
USE OF ENZYMES
There is an increasing trend of use of enzymes to enhance the feed utilization.
It can also be helpful by reducing the methane production thus help in reducing
the carbon foot print. Most of enzymes are cocktail of various enzymes (pentosanase,
pectinase and a-galactosidase activity and phytase) of bacterial or fungal origin.
Enzymes can be used for removal of antinutritional factors (e.g., 13-glucans
and arabino-xylans in barley grain cell-wail), increasing the digestibility
of nutrients (e.g., Phytate phosphorus in grains) and non-starch polysaccharides
(e.g., xylose and arabinose in plants). Bhatt et al.
(1991) reported the improvement in weight gain and feed efficiency with
supplementation of enzymes such as cellulose and hemicellulase in diet.
PREBIOTICS AND PROBIOTICS
Prebiotics are some oligosaccharide like fructo-, gluco- and galacto-oligosaccharides
resist attack by the digestive enzymes of animals and thus are not metabolized
directly by the host and act as bed for growth of beneficial microbes. Probiotics
are live microbial feed supplements which beneficially affect the host animal
by improving the intestinal microbial balance (Madan, 2005).
The most common probiotics are lactic acid producing bacteria.
ADDITION OF VACCINES OR ANTIBODIES IN FEEDS
Now a days many feeds and fodder are from crop plants that have been modified
for characteristics such as disease or pest resistance and their nutritive value
remain unaffected. Secondly, plants are used as bioreactors for the production
of recombinant biopharmaceuticals like cytokines, hormones, monoclonal antibodies,
bulk enzymes and vaccines (Miele, 1997).
Metabolic modifiers like recombinant bovine somatotropin (rBST) have been used to increase efficiency of production such as weight gain or milk yield per feed unit), improve carcass composition (meat-fat ratio). In developed countries like USA, its use increases 10-15% of milk yield. Similarly, researchers have also developed porcine somatotropin that increases muscle growth and reduces body-fat deposition, resulting in pigs that are leaner and of greater market value.
GENETIC MANIPULATION OF MICROBES
The rumen microbes can be altered genetically to increase their cellulolytic
ability and reduction in methanogenesis to improve the overall utilization of
feed and fodder. This can be done to eliminate the antinutritional factors in
feeds and also increase the essential amino acid specially limiting aminoacids
synthesis by rumen microbes. Attempts are being made to introduce the lignin
breakdown property into ruminal microbes. Depolarization of lignin by lignase
enzyme which is produced by the soft-rot fungus (Phanerochaete chrysosporium)
(Tien and Kirk, 1983) can be useful for the animals.
Efficiency and stability of lignase gene has been modified by Recombinant DNA
technology (Tien and Tu, 1987).
In developing countries, use of biotechnology in animal production is limited to some areas like conservation, animal improvement, healthcare (diagnosis and control of diseases) and increase supply of feed resources. By the adoption of biotechnology, the animal owners, livestock entrepreneurs will be benefitted. However, we have to address some issues like political will, infrastructure, funds and trained human resource. So, this is the time, when investment in biotechnology and animal nutrition is important for sustainability of human and animals, food security, rural health and wealth creation and for upliftment of poor people living in the villages.