Most tropical countries including India are facing an acute feed shortage, including greens. Crop residues, especially the cereal straws, are major roughages for feeding dairy animals. The fibrous and bulky feeds available are low in quality, lower in palatability and digestibility with lower energy, protein and mineral content. Apart from feed shortage, India is also facing regional feed disparity, with some states having enough green fodder and surplus straws, while the other states lacking in the supply of both green and dry roughages.

The bulky nature of crop residues makes its transportation difficult and costly. For this reason, straws worth hundreds of millions of rupees are burnt right in the field every year in some states. This burning not only causes feed loss but also causes environmental pollution (through the emission of greenhouse gases like methane, carbon dioxide and nitrous oxide) and soil degradation. Therefore, there is a need to improve our feed management which should include the use of specially designed bailers for the collection of residual straws from the field and subjecting these residues to processing technologies like the technology of densified complete feed block. This is a novel and a revolutionary approach, providing an excellent opportunity to feed manufacturers to remove regional disparities in feed availability and supplying balanced feed to the dairy and other livestock farmers on a commercial scale. Being a balanced feed, it offers variety of benefits to the animal (improvement in productive/reproductive efficiencies) and these gains later translated into owner’s prosperity.

The technology also offers the advantage of disaster management to overcome the problem of feeding animals during natural calamities of floods and draughts, and thus saving the animals from dying and hunger. There is also an alternative version of the technology available now, that is, Densified Complete Feed Pellets, which can be used for harder stems like straws of gram, soybean, cotton and mustard etc.

 Technology of straw based densified complete feed blocks

In countries like India, farmers can hardly follow any feeding standards as they lack the scientific knowledge as well as means to compute a balanced feed for their animals. This results in below optimum level of production from these animals, associated with reproductive irregularities. Each complete feed block is a total balanced ration for a cow or a buffalo for 24 hours and supplies all the major and minor nutrients, including micro nutrients required by the animal for optimizing its productive and reproductive performances.

 Composition of feed blocks: Straw based densified total mixed ration (TMR) or densified complete feed block has two major components and one minor component. The major components are roughage and concentrate, added in different ratios, depending upon the level of production, stage of lactation and the physiological state of the animal. The third component is micronutrients & feed additives. The roughage part is generally the crop residues like wheat and paddy straw, sorghum stalk, sugarcane tops. Sometimes gram straw, sugar cane bagasse and groundnut shells, dried forest grasses and tree leaves have also been used in place of straws and stovers.

The second major component of the densified feed block is the concentrate part. The proportion of the straw and concentrate in the block varies with the type of animal. The ingredients of the concentrate mixture are as usual: oil cake meals (as protein source}, molasses, grains, grain products/byproducts (as energy sources) and critical supplements like bypass protein/bypass fat, to enhance the direct supply of amino acids and fatty acids to the host animal. The third component provides strategic and catalytic supplements, the additives like micronutrients, vitamins, minerals, probiotics, antioxidants, antitoxins, herbal extracts etc. The role of these components in the feed block is to enhance the productive and reproductive efficiency of the animal and also enhance the immuno-protective ability to keep the animal as much as possible free from diseases. The value addition of the feed blocks can be a continuous research process under R&D.

 Method of manufacturing feed blocks: The making of feed block requires proper processing and can be manufactured on a large scale in a factory. The concentrate mixture is prepared separately and then mixed with chopped straw (using a proper ratio) in a specially designed mixer, to ensure proper mixing of the two components which vary greatly in their densities. The weighed quantity of the mixed feed is then pressed in a specially designed hydraulic press. The process of densification causes the concentrate particulate matter to get physically attached to fibrous roughage particles with the help of binder, so much so that there is hardly any scope for the animal for any selectivity. This not only brings uniformity to the feed, but also increases the palatability of the straw based feed and minimises the feed wastage.

 Advantages of adopting the technology of densified feed blocks

A few agencies in India have taken the initiative of developing and of refining feed block technology. Results of the on-farm feeding trial on feed blocks conducted at Poshak Agrivet Farm in Karnal, and the feedback collected from the farmers, exclusively feeding feed blocks to their dairy animals in Uttarakhand showed a significant increase in milk production in the experimental group (10-15 per cent increase in milk yield) compared to normal feeding pursued by farmers. Although the feed cost was higher in the experimental group by 25 per cent, the profit earned was still around 15 per cent more as compared to normal feeding. In fact, several benefits have accrued to the dairy farmer on shifting to the use of straw based densified feed blocks. These are:

 A balanced ration for ruminants: In India, it is normally very difficult for illiterate or semi-literate farmers to compute a balanced feed for their animals, except the practice being followed at organised farms. Densified TMR is a complete balanced feed. The optimum nutrients supplied through TMR to the animal can improve nutrient utilisation, resulting in optimum productive and reproductive performance from the animal, with the additional advantage of reduction in methane emission from the rumen.

 An efficient nutrients delivery system which reduces wastage: The feeding is almost simple and hassle-free. In separate feeding system, the animal picks up the more digestible/palatable parts first, and the residue left over has more of less digestible parts of the feed, which mostly go as waste. Feeding of densified TMR reduces this kind of wastage, as the animal does not get any chance for selecting more digestible stuff from the wholesome and uniform feed.

 Time and labour saving: By TMR feeding, the labour expenditure is reduced by 30-40 per cent. Being a readymade feed, the farmer can feel relaxed about feeding of animals, when the densified feed is in stock. In just 10 minutes 20-25 animals can be fed, as against 2-3 hours required for feeding same number of animals with a conventional feed.

 Cheaper and easier to transport: Densification of the straw based feed under mechanical pressure reduces its bulk by about three times. Accordingly, lesser storage space is required to store the feed, especially straws. The related advantages of this can be that the extra space could be used for other activities at the farm. Since the feed blocks occupy lesser space/volume, almost three times more blocks (by weight) can be accommodated and transported within the same space than the loose straw. This makes the transportation of crop residues based feed much easier and cheaper.

 Reduce environmental pollution: Densified complete feed as block, being prepared by mixing straw with concentrate along with other supplements and feed additive, makes it a complete balanced feed. It has been proved beyond doubt that balanced feeding reduces the methane emission by 10-15 per cent. Also there is less dust pollution when the feed is transported as blocks rather than as loose straw in trucks plying on Indian highways. Furthermore, in the North-Western parts of India, straw worth hundreds of tens of millions of rupees is burnt in the field itself after harvest. If this residual straw is converted into feed blocks, this feed resource can be saved, apart from preventing environmental pollution and degradation of soil fertility, caused by burning of straw.

 Improve productive efficiency: Feeding of densified complete feed block has a positive effect on both production and reproduction. While the growth rate of calves can go up by 25-30 per cent, the daily milk yield can show an increase by 10-15 per cent. After feeding densified TMR, the peak milk yield of the animal persists over a longer period of time, causing increase in total lactation yield. Due to the absence of dietary fluctuations, the rumen microbes get used to the same type of feed regularly resulting in stability of microflora and thereby increase rumen efficiency and feed digestibility.

 Improve reproductive efficiency: Because of faster growth rate, feeding of densified complete feed blocks results in early maturity and early age of first calving. This has a significant effect on lowering the cost of rearing and increased number of calving due to reduced calving intervals, which results in increase in life time of animal productivity. The animals can be kept free from reproductive problems such as late maturity, anestrous repeat breeding conditions, etc. The optimum supply of nutrients, including micro-nutrients has also a very positive effect on the health of the animals. The block feeding keeps them comparatively free from common metabolic disorders, reproductive disorders and provides immune-protection against infectious diseases. This also saves the farmer from the expenses incurred on the treatment of his animals.

 Storage of bulky feeds possible: With the availability of feed block technology, it is now possible to set up such feed/fodder banks in feed deficit areas, because of easy handling, easy transportation and easy storage of the straw based feed. Feed block technology can be most beneficial during natural calamities of flood and draught, to save the livestock from hunger and death. The blocks can even be air lifted to the remotest places to avert disasters.

 Vehicle for feed additives/medicines/neutracuiticals: In straw based complete feed blocks, there is so much room for improvement. Its value addition could be a continuous exercise through extended research, trying different supplements, newer feed additives, medicines like anthelmintics, nutraceuticals, including herbal extracts to improve its overall quality. TMR can offer the best delivery system for specific nutrients, a carrier for nutraceutical and anthelmintics to control parasitic infections in the region where the livestock has been infested.

 Status of application

Because of its multiple benefits to the animal, farmer and to the entrepreneur, straw-based densified feed block technology has a bright future in a country like ours. About 10 units commercial feed block production units have been set up by dairy cooperatives and state livestock development boards, and many more are in the pipeline. The Government of India, realizing the potential of this technology in enhancing livestock production, has thoughtfully decided to offer 50 per cent subsidy for setting up fodder block production units. This is acting as an incentive for cattle feed entrepreneurs and dairy cooperatives to take up the commercial manufacture of densified complete feed blocks on a large scale. Apart from improving the productivity of dairy animals, the technology has an additional attraction to offer a disaster management measure during natural calamities to save the animals from death and hunger.

For these reasons, FAO has recently identified this technology for adoption by dairy farmers in whole of the tropical region. FAO has also published a bulletin on ‘Crop residue based densified total mixed ration–A user-friendly approach to utilise food crop by-products for ruminant production’, authored by Dr T.K. Walli, Dr M.R. Garg and Dr. Harinder P.S. Makkar (FAO Animal Production and Health Paper No. 172. Rome, Italy).