(a) Fig. 6.1 shows a four-paddock rotational grazing system. The arrows show the direction in which a herd of 60 goats is moved between paddocks. Fig. 6.1 (...

Labelled answer diagram:

(a)(i) In a four-paddock rotational system, the herd occupies one paddock at a time. The remaining 3 paddocks are resting at any one time [1].

(a)(ii) Rest period calculation:

While the herd grazes one paddock for 14 days, the other three paddocks rest in sequence:

\[ \text{Rest period} = 3 \times 14 = 42 \text{ days} \quad [1] \]

(b)(i) With eight paddocks, the herd still occupies one paddock at a time, so seven paddocks rest simultaneously:

\[ \text{New rest period} = 7 \times 14 = 98 \text{ days} \quad [1] \]

The rest period increases from 42 to 98 days.

(b)(ii) Two benefits of the longer rest period (any two for [2]):

1. Fuller grass recovery - grasses have more time to regrow leaves, replenish root carbohydrate reserves and produce new tillers, resulting in a denser, more productive sward when the herd returns [1].
2. Parasite control - most gastrointestinal parasite larvae on pasture die within 6-8 weeks without a host. A 98-day rest exceeds this survival period, so animals return to pasture with a greatly reduced parasite burden, improving animal health [1].

Also acceptable: allows desirable grasses to set seed, improving sward composition.

The diagram shows the four-paddock layout. "W" marks the central water trough. The herd rotates through the paddocks, with three always resting.

(c) Placing the water trough at the centre of the paddock system rather than in one corner ensures that animals from any paddock walk a roughly equal distance to drink [1]. Corner placement would cause disproportionate trampling, soil compaction and overgrazing near the water point, while central placement distributes animal traffic more evenly across all paddocks [1].

(d) One suitable supplementary fodder crop for the dry season (any one for [1]):

Napier grass (Pennisetum purpureum) [1]. Also acceptable: Leucaena, sweet potato vines, maize stover, Desmodium.