Small-ScaleDairy Farming Manual |
Volume 1 |
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Lactation PeriodThe composition of the milk varies throughout the lactation cycle. During the first days of the laceration cycle composition of the milk varies a lot from the resting period. The milk which is secreted during the first days after calving is called colostrum; it has an increased content of protein and ash. Colostrum contains 20-30% dry matter. The variations in milk in the remaining lactation cycle is shown in Figure 3. Together with increase in fat content , the content of the protein and ash also increase mainly due to an increase in the salt content.
Figure 3: Variations in milk Composition During the Lactation Period.
Right after calving, the milk is called Colostrum milk:
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What affects milk composition ?
Lactation Period
47 Right after calving,
your cow gives colostum milk. You cannot deliver this to the milk collecting centre. |
48 After 4-5 days
the composition is normal and you can deliver your milk. |
49 Compare the differences in milk - at birth and - after five days. |
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Time of MilkingCows are normally milked twice a day: early morning and late afternoon. Milk obtained at the morning milking is much lower in fat (e.g. 3 percent) than at the afternoon milking (e.g. 5 percent).This is not because fat secretion
is reduced in the longer night interval but because there is a net carryover
of residual milk rich in fat from the night to the day interval.
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50 Morning milk has
lower fat content (about 3 parts in 100 ) than evening milk (about 5 parts in 100 ). |
Type of AnimalTable 2 gives representative values for the main constituents of nutritional importance of the milk of humans and the milch animals. The composition of milk not only differs from species to species but varies widely within any one species and even within breeds or races of one species. Many factors determine composition: physiological variability of the individual, nutrition, stage of lactation, age, season of the year, amount of milk produced - to name only a few. It is clear, therefore, that the values given in the tables can only serve as a general guide and departures from them will be found in quite normal individual animals or herds. The main milch animals have been bred for centuries to produce quantities of milk far in excess of the amounts needed by their young. The milk of these domesticated and highly specialized animals retains the main characteristics of that of the wild stock. As a rule, however, the milk given in much smaller quantity by the wild or less domesticated animals is "richer" in that it contains more nonfatty solids and often more fat. The cow is more generally used throughout the world than any other milch animal and more is known about its milk, hence the examples quoted for it in the tables are likely to be more accurate.
good quality milk of different species 1 In the table a dash (-) denotes lack of information or unreliable information. |
Type of
Animal
52
Milk from different animals has different compositions ( g/100g ).
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Other Factors
The following also affets the composition of milk.
53 Breeding |
54 Feeding |
55 Hygiene |
56 Health
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57 Temperature |
58 Handling |
Ask your extension worker for advice about these factors.
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