The level of vitamins $A$ and $K$ is kept high in poultry feeds.

$(a)$ Mention the harmful effects of infectious diseases on the health of cattle.
$(b)$ How can these diseases be controlled?

What are the advantages of composite fish culture?

$A$ farmer wanted to invest some money in fish farming. But he did not get right guidance.
$(a)$ How can you guide him for a profitable business in spite of limitations of fish farming?
$(b)$ What is the limitation of fish farming?

What would happen if poultry birds are larger in size and have no summer adaptation capacity? In order to get small-sized poultry birds having summer adaptability,what method will be employed?

Which method is commonly used for improving cattle breeds and why?