Part IV of the livestock productivity model (Figure 2.1) formulates the livestock feed requirements,taking into account maintenance and production needs.
Feed requirements have been formulated to support the herd performances quantified in Section 6 for the individual livestock systems.
In order to support the body's processes and promote production, animals must consume regular supplies of various nutrients. These nutrients may be broadly defined as energy (from carbohydrates and fats), protein, vitamins, minerals and water. They are contained in animal feeds, which are largely of plant origin, in different concentration and combination. Under most intensive systems of animal husbandary, the animal may not always be able to obtain a balanced diet throughout the year because of the seasonal variation in the composition of the herbage.
Water is also needed by the animal, this is obtained from three sources: (a) drunk as water, (b) contained in the herbage or other feed, and (c) resulting from the oxidation of carbohydrates in the tissues. Availability of water is a problem in some parts of Kenya, and much of the pastoral zone has limited permanent water forcing nomadic behaviour. Certain stretches of the country have no water resources. Such a situation must be taken into account in final estimates of livestock carrying capacities. The available sources of information include data which would enable these areas to be identified and measured at the district level and this should be incorporated in the model for a more effective treatment.
A summary of reference feed requirements per herd TLU is given in Table 7.1 for non-pastoral and pastoral systems for three levels of inputs situations. In the non-pastoral systems, intake requirements for cattle, goat and sheep are based on field verification for the herd structures presented in Section 5 for the performance output levels described in Section 6. In the model, crop residue intake in the non-pastoral systems is limited to 30%, 20%, and 10% of total feed intake respectively in the low, intermediate and high technology system.
For pastoral systems, feed requirements are based on Boudet and Riviere (1968) for the herd structures and performances presented in Sections 5 and 6. For poultry and pig, the standard requirements are used (FAO 1988b).
Feed requirements for each system are presented hereunder.
TABLE 7.1
Feed requirements per herd TLU (kg/day dry weight)
| Livestock system | Inputs level | |||
| Low | Intermediate | High | ||
| Pastoral (<120 days LGP) | ||||
| - | Cattle | 7.0 | 7.2 | 7.4 |
| - | Goat | 6.6 | 6.8 | 7.6 |
| - | Sheep | 6.6 | 6.8 | 7.0 |
| - | Camel | 6.5 | 6.6 | 6.7 |
| Non-pastoral(>120 days LGP) | ||||
| - | Cattle | 7.8 | 8.5 | 8.91 |
| - | Goat | 10.0 | 11.5 | 16.12 |
| - | Sheep | 9.1 | 11.3 | 11.6 |
1Includes 1.2 kg/day primary products (3.2 kg/day per lactating cow)
2Includes 4.8 kg/day primary products (0.6 kg/day per lactating doe).
In the low technology system, one cow unit requires about 3,740 kg dry matter (DM), corresponding to 1,650 kg total digestable nutrients (TDN) and 210 kg digestible crude protein (DCP) per year, for maintenance and production. These feed requirements are met by grazing Kikuyu/star grass pasture and maize stover.
In the intermediate technology system, one cow unit requires about 5,200 kg DM (2,560 kg TDN and 300 kg DCP per year) for maintenance and production. These feed requirements are met by grazing Kikuyu/star grass pasture and maize stover.
In the high technology system, one cow unit requires about 7,200 kg DM (3500 kg TDN and 420 kg DCP per year) for maintenance and production. This is provided by the napier/bana grass, by feeding maize stover and by feeding 1,165 kg concentrates.
The above requirements correspond to 7.8, 8.5 and 8.9 kg/day per reference herd TLU for the low, intermediate and high technology systems respectively (Table 7.1)
In the low technology system, one doe unit requires about 470 kg DM per year, provided by natural pasture.
In the intermediate technology system, one doe unit requires about 700 kg DM per year. This is provided by a combination of sources: natural pasture (280 kg), fodder crops (280 kg) and crop residue (140 kg).
In the high technology system, one doe unit requires about 960 kg DM per year. This is provided by fodder crops (610 kg), crop residue (140 kg) and concentrates (210 kg).
The above requirements correspond to 10.0, 11.5 and 16.1 kg/year per reference herd TLU for the low, intermediate and high technology systems respectively (Table 7.1).
In the low technology system, one ewe unit requires about 360 kg DM per year, provided by natural pasture.
In the intermediate technology system, one ewe unit requires about 610 kg DM per year. This is provided by a combination of sources: natural pasture, fodder crops and crop residue.
In the high technology system, one ewe unit requires about 750 kg DM per year. This is provided by natural pasture, fodder crops, crop residue and concentrates.
The above requirements correspond to 9.1, 11.3 and 11.6 kg/year per reference herd TLU for the low, intermediate and high technology systems respectively (Table 7.1).
For the pastoral systems (< 120 days growing period), feed requirements are based on a daily intake of 2.5 kg dry matter per 100 kg liveweight or 6.25 kg dry matter for the 250 kg reference TLU. Maintenance requirements are 2.9 FU/day and 160 g/day digestible protein (DP). The annual maintenance dietary needs of a reference TLU are thus 1,060 FU or 2,280 kg DM (1FU = 2.15 kg DM) and 58 kg DP. Production requirements are in addition at 350 extra FU/year (0.95 FU/day) and 28 kg DP (75 g/day) for weight gain of 100 kg/year (300 g/day) or a production of 1,000 kg/year(2.74 kg/day) of milk.
The above requirements correspond to 7.0, 7.2 and 7.4 kg DM/day per TLU for the low, intermediate and high technology systems respectively for cattle; 6.6, 6.8 and 7.0 kg DM/day per TLU for goat and sheep; and 6.5, 6.6 and 6.7 kg DM/day per TLU for camel (Table 7.1).
These animals are considered only under the intensive systems and standard requirements are used (FAO 1988b). For poultry these are 2.5 kg of feed (primary products) for 1 kg of meat, and 3,5 kg of feed for 1 kg of egg mass. For pig it is 4 kg of feed for 1 kg of meat.
