C Pelleting

The pelleting process usually involves treating ground feed with steam and then passing the hot, moist mash through a die under pressure. The pellets are then cooled quickly and dried by means of forced air. Sufficient water should be applied so that all feed is moistened. Pelleting at too low a temperature, or with too little steam, results in a 'shiny pellet', due to increased friction on the pellet going through the die. Often such pellets are only the original mash enclosed in a hard capsule and have not benefited from the 'cooking' process brought about by moisture and heat.

Optimum moisture content of a feed required for good pelleting will vary with the composition of the feed, however, a range of 15 to 18% moisture is usually desirable. Feeds containing liberal quantities of high fiber ingredients will require a higher level of moisture while feeds low in fiber will require less moisture. A good pellet, when hot, can be reduced to two-thirds of its length without crumbling. Such feed has been 'steam-cooked' and holds together well. Rations can be pelleted at any temperature up to 88°C that will allow for maximum production per hour without any major fear of vitamin destruction.

Feed mills sometimes experience difficulty in obtaining good pellets when manufacturing corn-soybean diets containing added fat. Products such as lignosol or bentonite are reasonably effective as binding agents, however, they a have little nutritive value, and so one should consider whether the advantage of introducing such material into pelleted or crumbled diets warrants the cost. The inclusion of 10 to 15% of wheat, wheat middlings or to a lesser extent barley will often give a pellet of satisfactory hardness. When these ingredients are too expensive, the addition of about 2% of extra water to the mash will aid in producing a better pellet. If this procedure is followed, however, extra drying of the pellets is required so that mold growth does not occur during storage. Work in our laboratory has indicated that molasses may be used as a pellet binder. In addition to aiding in pelleting, molasses unlike other binders, also contributes energy to the diet and so inclusion levels of 1 to 2% in certain diets may be beneficial.

In addition to the advantages of less feed wastage and ease of handling, pelleted diets are more efficiently utilized by poultry. While some of this improvement is due to chemical changes brought about by heat, moisture and pressure, a significant part of the enhanced efficiency is due to birds spending less time when eating pellets resulting in a reduction in maintenance energy requirements by the bird. This situation was demonstrated in the classical study by Jensen et al. (Table 2.27).

Table 2.27 Time spent eating mash and pelleted diets

Av. time spent

Av. feed

AGE

eating

consumed

(min/12 hr day)

(g/bird/12 hr)

Mash

Pellets

Mash Pellets

Turkeys

(38-45 d)

136

16

62 57

Chickens

(21-28 d)

103

34

38 37

Jensen et al. (1962)

Jensen et al. (1962)

The need for good quality pellets is often questioned by feed manufacturers since regrinding of pellets or crumbles and feeding these to birds has little apparent effect on performance.

There seems little doubt that good quality crumbles and pellets can be advantageous for improving the growth rate of turkeys. However, pellet quality seems of less importance with broiler chickens, especially where high-energy diets are considered. More important in the pelleting process is the treatment of feed with steam and pressure, although it is realized that in certain markets it is difficult to sell feed that is not of 'ideal' pellet quality.

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Pregnancy Diet Plan

Pregnancy Diet Plan

The first trimester is very important for the mother and the baby. For most women it is common to find out about their pregnancy after they have missed their menstrual cycle. Since, not all women note their menstrual cycle and dates of intercourse, it may cause slight confusion about the exact date of conception. That is why most women find out that they are pregnant only after one month of pregnancy.

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