Total mixed ration is a method of feeding dairy cattle. The purpose of feeding a TMR diet is that each cow can consume the required level of nutrients in each bite. A cow's ration should include good quality forages, a balance of grains and proteins, vitamins and minerals. By using a TMR diet, the operations can be divided into groups such as having at least three milk production groups, and one dry cow group. By being able to manage the TMR daily it provides healthy cows, increases in milk production and reproduction. The key to formulating TMR is maximized dry matter intake, which should be consistent with production and breed.
Advantages
The dairy farmer has more control over the feeding program.
gives you more of an ability to control the feed giving to certain cows
All forages, grains, proteinsupplements, minerals and vitamins are thoroughly mixed. Therefore, the cow can do very little sorting for individual ration ingredients.
Completely blended feeds, coupled with grouping the cows, permits greater flexibility in feeding exact amounts of nutrients to more accurately feed cows for their particular stage of lactation and level of milk yield.
Grain mixtures can be liberally fed to grouped high producers without overfeeding the late-lactation or lower-producing cows, resulting in more efficient use of feeds.
Disadvantages
Cows should be grouped by production levels.
Grouping cows is not feasible in small herds.
Grouping cows is not easy if the cowshed cannot handle various numbers of cows in each group
If not grouped according to production, cows in late lactation are likely to get too fat.
Special equipment is needed.
The equipment must have the capability to thoroughly blend the feed ingredients.
The mixer-wagon, preferably mobile, must be capable of accurately weighing each ingredient.
Management
Cows generally sort through long particles in search of finer particles. This behaviour can cause problems such as subacute ruminal acidosis. Not only does it cause rumen problems, it also causes an effect on their NDF intake. The sorted diet contains more fermentable carbohydrates and less fiber thus not only creates problems for the cow's health but also wastes money and time for the provider. Therefore it is essential to have a balanced TMR diet. This can be achieved by harvesting the forage properly before ensiling. thus the silage and haylage should be chopped 3/8-3/4 in length. Forage that is too fine or too course should be avoided due to the cow's ability to sort. The number of groups of animals to be part of a TMR diet depend on existing herd size, the layout of barn, and loafing areas. typically a barn will have high, medium and low production lactating cows, far off and close up dry cows, and pre-breeding and post-breeding heifers. These groups are essential has some don't do well in overcrowded feed areas. When working with two or three groups it is easier as you can feed the low costing forage to the low group and the high quality forage to the higher group in which can obtain or increase the overall health and performance of cows. For dry cows this system can minimize metabolic and nutritional disorders in calving and post-partpartum period. A pre-breeding and post-breeding system is essential for heifers to ensure proper growth and development. It is important for pre-breeding heifers to have an energy- and protein-dense diet while post-breeding lack the ability to consume high forage diets.
Summary
Complete rations feature the blended approach; all forages, concentrates, protein supplements, minerals and vitamins are mixed and offered as a single feed.
Complete-ration systems can save labour and reduce overall feeding costs.
It is extremely important to keep the mixture exactly the same day after day and to make big changes gradually.
Early detection of problems with the ration system is possible by observing the bulk tank milk level after each milking.
TMR can be used effectively by many dairy farmers, but it is not a substitute for good management. In fact, the intensity of management may be increased. Most of all, management skills and competency of the dairy farmer are critical to make this system work effectively.