Category of cattle Concentrate feed (kg/day) Roughage (kg/day) Total dry matter (kg/day) Dry cow 1.5 7.0 8.5 Lactating cow 5.0 9.0 14.0 Growing heifer (12 m...

(a) Category of cattle requiring the most feed per day [1]

The lactating cow requires the most feed: 14.0 kg total dry matter per day (5.0 kg concentrate + 9.0 kg roughage). [1]

(b) Why the lactating cow needs more feed [2]

1. A lactating cow needs extra energy and nutrients above her own body maintenance to support milk synthesis. Milk production is metabolically demanding - each litre of milk requires significant protein, energy, calcium, and water. [1]
2. She needs a production ration on top of her maintenance ration; the higher concentrate allocation (5.0 kg vs 1.5 kg for a dry cow) reflects this additional demand to sustain high milk yields. [1]

(c) Two roughage feeds for cattle [2]

Any two of:

1. Hay - dried grass or legume herbage, a staple roughage with moderate protein. [1]
2. Silage - fermented, preserved green forage (e.g. maize silage, grass silage). [1]
3. Straw - dried cereal stems (low nutritive value, mainly fibre).
4. Fresh grass / pasture - grazed directly.
5. Maize stover / crop residues - dried stalks and leaves left after grain harvest.

(d) Difference between maintenance ration and production ration [2]

1. A maintenance ration provides just enough nutrients and energy to keep the animal alive and healthy, maintaining body weight without gaining or losing condition. It covers basic metabolic processes such as breathing, circulation, and body temperature regulation. [1]
2. A production ration supplies additional nutrients above maintenance for a productive purpose - such as growth (in young stock), milk production (in lactating cows), reproduction (in pregnant animals), or work (in draught animals). [1]