Table Influence of diet energy on growth and nutrient intake of leghorn pullets maintained at or C t

Temperature 18°C

2500 kcal ME/kg 3000 kcal ME/kg

Temperature 30°C

2500 kcal ME/kg 3000 kcal ME/kg

Body wt 126 d Total feed intake ME intake (g)_(kg)_(Mcal)

Protein intake _(g)_

1398 1434

1266 1218

6.05 5.19

  1. 04 21.07
  2. 17 15.69

1330 1160

1010 870

all other nutrient levels were fixed, this resulted in reduced intake of all nutrients except energy. Pullets therefore ate less protein and amino acids when fed 3000 vs. 2500 kcal ME/kg, and this can be critical where intake per se is less at 30°C. The pullets fed 3000 kcal/kg are borderline in intake of balanced protein at 870 g vs. our requirement for 800 g to this age. High energy diets may therefore not always be beneficial under heat stress conditions, and intake of other nutrients such as protein and amino acids must be given priority during formulation. The Leghorn pullet eats for energy requirement, albeit with some imprecision, and so energy:protein balance is critical. All too often there is inadequate amino acid intake when high energy corn-based diets are used, the result of which is pullets that are both small and fat at maturity.

One of the most important concepts today in pullet feeding, is to schedule diets according to body weight and condition of the flock, rather than according to age. For example, traditional systems involve feeding starter diets for about 6 weeks followed by grower and then developer diets. This approach does not take into account individual flock variation, and this will be inappropriate for underweight flocks. It is becoming more difficult to attain early weight for age. This means that flocks are often underweight rel ative to management guide values (Table 3.12) at 4-6 weeks of age. This situation can arise for a variety of reasons such as sub-optimal nutrition, heat stress, disease, etc. For such flocks it is inappropriate to change from starter to grower diet, merely because the flock has reached some arbitrary age. It is more appropriate to feed the higher nutrient dense starter until the target weight is reached. For example, Figure 3.2 shows an underweight flock at 6 weeks. For this flock to receive a grower at 6 weeks of age will cause problems because the flock will likely stay small until maturity, be late maturing, and then produce a sub-optimal number of eggs that will also be small. This type of flock can most effectively be 'corrected' in growth by prolonged feeding of the starter diet. In this situation, the birds reach the low end of the guide weight at almost 10 weeks of age (Figure 3.2). At this time, a grower diet could be introduced. Since the flock is showing a growth spurt, then feeding to almost 12 weeks could be economical. The flock is now slightly over-weight and so ideally suited to realizing maximum genetic potential during peak production. Some producers, and especially contract pullet growers, are sometimes reluctant to accept this type of program, since they correctly argue that feeding a high protein starter diet for 10-12 weeks will be more expensive. Depending upon local economic conditions,

  1. 3.2 Pullet growth in relation to feeding program.
  2. 3.2 Pullet growth in relation to feeding program.

feeding an 18% protein starter diet for 12 vs. 6 weeks of age, will cost the equivalent of 2 eggs. A bird in ideal condition at maturity will produce far in excess of these 2 eggs relative to a bird that is underweight at maturity.

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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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