Are they sustainable?
S Rajeshwaran
Feeding cattle based on standards and prescriptions may not always lead to a better productivity of livestock. It may be cost intensive, harmful and unsustainable. Feeding cattle based on the understanding of rumen physiology and nutrient requirements is more cost effective and sustianable.
Veterinarians in India are inundated with emergency calls post festivals like Sankranti to treat cows and buffaloes suffering from acute ketosis due to feeding of rice and jaggary in large quantities. If not treated immediately it can even result in their death. This indicates that stomach of cows and buffaloes consisting of four compartments rumen, reticulum, omasum and abomasum are not equipped to handle foods like cereals and oilseed cake.
Cows and buffaloes are bovines. They along with ovines, sheep and goat have the ability to regurgitate their food and chew and hence called ruminants in general. Regurgitation takes place from the reticulum and this process is called rumination. The purpose of rumination is to masticate the food into finer particles, digest the cellulose in plants with enzymes from saliva and prepare it for ingestion by the bacteria in the rumen. It is this bacteria that form the food of the animal after digestion with an enzyme called lysozyme secreted by abomasum. Essentially, the stomach of a ruminant is a fermentation vat where bacteria grow. For this, a constant temperature and pH are of utmost importance.
Any activity that decreases ruminal motility, regurgitation process and results in a change in pH or temperature of the stomach content is detrimental to the health of the animal. A cow or buffalo produces about 100 to 150 litres of saliva, during the mastication process. It is this alkaline saliva that is critical for maintaining pH in the stomach and blood. Feeding of high proportion of concentrates to animal leads to subclinical ketosis and associated with loss in milk production. Research has also shown that higher roughage feeding results in higher milk production. Similar result has been seen in Kolar and Chikkaballapur districts of Karnataka in India also.
To highlight the difference of ruminants from other single stomached animals, we compare poultry which is reared for meat or egg purpose under intensive farming system. Birds are physiologically tuned to eat and digest seeds in their stomach called gizzard and not mouth as they lack teeth. Hence, feeding of seeds of cereal is a natural process and advising farmers to feed them with cereals and balanced concentrate feeds is in order.
It is against such documented research and practical observations that dairy farmers continue to feed wheat or rice husk, cereals, oilseed cakes, balanced concentrate feed and chaffed dry and green fodder of less than 1 inch to their cows and buffaloes! In fact, they are being advised to do to enhance milk production from their animals. It does increase milk production in the short-term. However, this increase is due to the fact that majority of cows and buffaloes in India suffer from negative energy and protein imbalance. Hence, any feeding that reduces the short-fall in any one of the two improves the general health and hence milk production. In fact, feeding of these materials with limited quantity of water and roughage does not even fill the stomach of the animals resulting in low or even dissatisfaction. Limited quantities are fed because these feeds are costly and need to be bought on cash-basis from external sources.
Feeding of high proportion of concentrates to animal leads to subclinical ketosis and associated with loss in milk production.
Feeding fodder giving sufficient time for rumination is a sustainable way to feed cattle
It is probably based on these factors that dairy farmers in New Zealand and Australia do not feed their cows concentrate nor do they chaff the fodder,and rear their animals under extensive farming system. This gives their animals sufficient time to not only browse grass with clover, carbohydrate and protein source on their own but also rest and ruminate. In fact, these two countries are the cheapest producers of milk in the world followed by India, which is a strategic sectoral strength.
Further, feeding concentrates especially cereals to ruminants puts them in competition with humans. This competition and resultant higher demand leads to higher price. The poultry sector is already a big consumer of cereals, especially corn and in direct competition with humans causing a serious shortage in the domestic market.
Hence, feeding of cereals, oil-seed cakes and balanced concentrate feeds and finely chaffed green and dry fodder are cost ineffective and even harmful. Unrestrained feeding of green and enriched dry fodder with a mix of grass and legumes in the weight ratio of 3:1 with length of above 6 – 8″, giving sufficient time for rumination at equal time intervals over the day is a cost-effective and sustainable way to feed and rear dairy animals.
References
http://www.vivo.colostate.edu/hbooks/pathphys/digestion/herbivores/rumination.html
Andersson, L., Subclinical ketosis in dairy cows, 1988,Veterinary Clinics: Food Animal Practice 4
Duffield, T., Sub-clinical Ketosis in lactating dairy animals, 2000, Veterinary Clinics of North America: Food Animal Practice 16(2): 22.
Leslie, K., T. Duffield and S. Le Blanc., Monitoring and managing energy balance in transition dairy cows, 2003, Journal of Dairy Science 86: 101-107.
Netsanet, B., V. Kapoor and B. Tewatia., Effect of roughage to concentrate ratio in the diet on milk production and fatty acid profile of milk in crossbred cows, 2015, Indian Journal of Animal Nutrition 32(4): 373-378.
Harisha, K., K. Satyanarayan, V. Jegadeeswary, L. Achoth,Y. B. Rajeshwari and C. S. Nagaraj., Milk production trends in Kolar and Chikbalapur districts of Karnataka, 2015,Asian Journal Dairy and Food Research 34(2): 3.
S Rajeshwaran
Visiting professor and senior research consultant,
IRMA, Anand – 388001
E-mail: sraj@irma.ac.in
