Page 248 - Agriculture_Form_Three

Agriculture for Secondary Schools

Factors affecting milk quality
There are many factors that affect the milk quality. The major ones include:
(a) Contamination during milking: If you will not be very careful during milking,
you may contaminate the milk with other foreign materials.
(b) Presence of antibiotics: If an animal is treated with antibiotics, the residues of
the drugs may appear in the milk. Thus, the milk produced by that animal will
not be fit for human consumption for some days. To avoid this, strictly adhere
to withdrawal period after using any drug to animals.
(c) Nutrition: The chemical composition of milk can easily be influenced by the
diet given to the lactating animal. Animals fed more succulents will produce
milk with low density while feeding hay would increase the total solids in the
milk.
(d) Animal health: Lactating animals with poor health condition will produce lower
quality milk. For example, animals with mastitis and brucellosis produce milk
that is unfit for human consumption.
(e) Stage of lactation: A dairy animal produces the first milk called colostrum,
immediately after parturition, which has completely different composition
compared to whole milk. As the lactation proceeds, the composition changes to
that of whole milk.
(f) Breed: Due to genetic factors, different breeds have different milk composition,
hence, different qualities. For example, Jersey breed gives milk with higher
butter fat content (4.6%) than Friesian which produces milk with lower fat
(3.5%) content.
Activity10.8
Perform the following tasks:
1. Obtain a sample of milk from your school farm or nearby farm and observe any
features that indicate the quality of the milk. List down all of them.
2. Where there is more than one animal in lactation, request and record its yield
for at least a month. Comment on your observations.

Exercise 10.5
Answer the following questions:
1. What is the meaning of the following terms?
(a) Milk quality
(b) Milk yield
2. State any four (4) factors that affect milk yield.
3. Outline any four (4) measures you can take to avoid low milk yield.
4. Explain any three (3) factors affecting milk quality.

Student’
Student’s Book Form Twos Book Form Three
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AGRICULTURE FORM 3 9.11.2022.indd 237
AGRICULTURE FORM 3 9.11.2022.indd 237 10/01/2025 12:32