Complete feed system in ruminants
Complete feed system for feeding dairy animals is a departure from conventional individual rationing method. It involves the self-feeding of mixed diets based on a variety of available ingredients. The objective of the system is to simplify the process of feeding dairy animals so as to save labour, reduce capital costs on building and to provide ration of uniform composition. Traditionally, complete feed system is practiced in India which involves the mixing of chopped material with straw and water soaked feed ingredients such as oil cakes, wheat bran, wheat flour or with compound feed depending upon their availability and/or level of animal production. Such mixed feed is commonly known as total mixed ration or sani. Under other conventional system, the animals are fed concentrate at specific hours and ration is formulated to meet out the individual’s requirement according to the level of production. In this case animals may preferentially consume more of concentrate and do not have preference to the roughage, thereby creating problems in rumen function. Self-feeding system, based on a diet broadly adjusted to the stage of lactation/growth is acceptable and has the advantage of eliminating differences in the roughage to concentrate ratio among the animals. The complete feeds are processed in different ways such as:
Chaffed mix: Roughages are finely chaffed and evenly mixed with ground concentrate ingredients
Silage mix: Finely chaffed silage is evenly mixed with concentrate ingredients at the time of feeding
Mash mix: Roughages are ground and evenly mixed with ground concentrate ingredients
Pellets/ cubes: Roughages are ground, evenly mixed with ground concentrate ingredients and converted to pellets/ cubes
Feeding of complete feed or total mixed ration results in better performance of an animal besides reducing the wastage due to:
(a) Increased voluntary intake
(b) Increased nutrient digestibility
(c) Increased efficiency of utilization of digested nutrients for productive purposes. Pelleting of roughages increases the voluntary intake of ration than that in mash form. However, nutrient digestibility is generally reduced due to the higher rate of passage of digesta as roughages are generally ground before pelleting. Particle size reduction of roughages affects the nature of microbial fermentation and reduces the time of exposure of feed to rumen microorganisms. However, feeding of pelleted roughages improves nitrogen retention. Higher body weight gain was recorded following the feeding of alkali treated wheat straw based pelleted complete feed than on untreated straw based pelleted and mash feeds as a result of higher palatability, without any adverse affect on rumen fermentation.