(a) State three changes that take place after the chopped forage has been compressed and covered in silage preparation.
(b) Give two reasons each for carrying out each of the following practices in pasture management; (i) weeding; (ii) controlled burning; (iii) Irrigation; (iv) Fertilizer application; (v) Liming.
(c) State two functions of phosphorus in animal nutrition.
(d) Complete the table below by ticking (✔) the appropriate column to indicate the effect of low temperature on farm animals.
| Parameter | Increase | Decrease | Normal |
| (i) Water intake | |||
| (ii) Grazing time | |||
| (iii) Milk yield | |||
| (iv) Feed intake | |||
| (v) Egg production |
Explanation
(a) Changes that take place after chopped forage has been compressed and covered in silage preparation: - Oxygen is used up. -Carbon dioxide is increased. -Rise in temperature of ensiled mass. Bacterial ferment carbohydrates to produce lactic acid. -Fruity smell/alcoholic smell/esters produced. -pH is lowered. -Breakdown of fibre due to fermentation. -Gradual compression of ensiling material occurs/reduction in bulkiness. -Colour changes to olive green.
(b) Reasons for carrying out various practices in pasture management: (i) Weeding: - Reduces competition for air, water, nutrients, and space. -For better growth of herbage/good yield. -Get rid of pests. -Get rid of diseases. -Removes poisonous plants/obnoxious weeds. -Minimizes incidence of predators. -Enhances free movement. (ii) Controlled burning: - Kills eggs, and larvae of parasites/kills parasites. -Destroys old herbage/gets rid of old plants/regeneration. -Promotes new growth of pasture grass. -Controls weed. -Controls vermin. -Controls diseases. -Increases mineral content of soil. -Reduces soil acidity. -Controls pests. -Eliminates predators. (iii) Irrigation: - Maintains good growth of herbage. -For good yield/crop productivity. -For all-year-round production of pasture. -Availability of quality pasture. -Reduces dustiness. (iv) Fertilizer application: - For good growth of herbage quality grass and legume. -For high carrying capacity. -For higher yield/higher production. -For increased nutrients of pasture/fertility. -Neutralizes alkalinity. -Organic fertilizers improve soil structure. (v) Liming: - Neutralizes soil acidity/increases soil pH. -Improves soil structure. -Destroys the eggs of liver fluke. -Increases soil nutrients e.g. CaCo3/ fertility.
(c) Functions of phosphorus in animal nutrition: - For bone formation. -For teeth formation. -For eggshell formation. -For acid-base balance. -For the metabolism of fats and carbohydrates. -For milk production. -Precursor for protein synthesis.
(d) Parameters of farm animals when the temperature is low.
| Parameter | Increase | Decrease | Normal |
| (i) Water intake | ✔ | ||
| (ii) Grazing time | ✔ | ||
| (iii) Milk yield | ✔ | ||
| (iv) Feed intake | ✔ | ||
| (v) Egg production |
✔ |