Theory question 106
Pasture and Forage(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 | | |
Show the model answer
(a) Any three: the plant cells use up the trapped oxygen (respiration) and heat is produced; anaerobic bacteria ferment the sugars; lactic acid (and some acetic acid) is formed; the pH falls to about 4, which stops further bacterial and fungal action and preserves the forage; colour changes to yellowish-green with a pleasant sour smell
(b)(i) Weeding: removes competition for nutrients, water and light; removes poisonous or unpalatable plants; reduces pests
(ii) Controlled burning: removes old, dry, fibrous growth to encourage fresh shoots; kills ticks and other pests; controls bushes and weeds
(iii) Irrigation: supplies water in the dry season; keeps forage growing all year; raises yield
(iv) Fertilizer application: supplies nutrients; increases yield and quality/protein of forage; faster regrowth
(v) Liming: reduces soil acidity; supplies calcium; helps legume nodulation and nutrient uptake
(c) Any two: bone and teeth formation (with calcium); eggshell formation; energy metabolism (ATP); part of nucleic acids and cell membranes; acid–base balance; milk production; fertility
(d) Water intake: decrease; Grazing time: increase; Milk yield: decrease; Feed intake: increase; Egg production: decrease
In cold weather animals eat more to keep warm but drink less and produce less.