Nutrient Requirements of Goats: Angora, Dairy, and Meat Goats in Temperate and Tropical Countries

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RATION FORMULATION AND EXAMPLES OF TYPICAL RATIONS

Formulating practical rations requires (1) identification of the total nutrient requirements of a goat or herd of goats according to body size and the physiological functions to be satisfied, and (2) proper combination of available feedstuffs to supply these nutrients in the most economical manner. The requirements listed in Table 1 can be met in many different ways using different combinations of feed ingredients. Local availability and cost of ingredients will be the determining factors. Roughages are normally the least expensive and are considered first. The remaining requirements are met with concentrates. Requirements of goats are presented in Table 1 for:

Maintenance
Growth and live weight gain
Pregnancy
Milk production
Mohair production

Included with maintenance is a consideration of activity levels that are considered as part of “practical maintenance.” These increased levels result from foraging activity, travel, and climbing. Perhaps more than any domestic animal species, goats vary in degree of activity with breed, location, management system, and climate. Thus, four different levels of requirements for “practical maintenance” are considered:

Maintenance only, including minimal activity
Maintenance plus low level activity
Maintenance plus medium level activity
Maintenance plus high level activity

The maintenance requirement used to calculate ration examples assumes a largely minimal level of activity, but appropriate rations for goats in more active circumstances can be computed from the respective data for other levels in Table 1. Feeds in the temperate regions will vary considerably from those in the tropics, but a few typical feeds have been selected. While alfalfa hay, corn, and soybean oilmeal may be fed frequently in the temperate regions, in the tropics one might use rather Guinea grass, Cassava chips, coconut cake, and fish meal. Roughages include browse, tree leaves, and crop residues; their voluntary intake will be affected by the dry matter contents. Nutrient contents for all ration ingredients can be extracted from Tables 2 and 3. Rations satisfying all requirements can be calculated not only for energy and protein demands, as in the examples below, but also for minerals and vitamins, as far as nutrient needs are known on a minimum or a challenge basis of supply. Chapter 2 gives additional details for the use of Table 1. Ration formulation examples are based on Tables 2 and 3, but in many instances the data are inadequate or needs have not yet been established specifically for goats. Fortunately, legume forages are good sources of most mineral elements required by goats. When high-quality legumes make up half or more of the roughage in a dairy goat ration, as may be often the case in temperate countries, most of the mineral requirements, except possibly selenium, may be met. The situation can be different in tropical countries where fodder grass, with or without tree leaves, rather than legumes is more commonly fed, and additional mineral needs have to be satisfied. With dependence on legumes, however, phosphorus and sodium may be deficient enough that supplementation will be necessary. The sodium requirement can usually be fulfilled by including 0.5 percent salt (sodium chloride) in the concentrate mixture, or by providing it ad libitum as granular salt or salt block.

When poor quality roughages including legumes, forages, and tree leaves are predominant in a ration, more extensive mineral supplementation with calcium, phosphorus, manganese, zinc, copper, iron, selenium, iodine, and cobalt is required. Where possible, all forages should be tested for their mineral content because extreme variation is common, particularly with tropical feedstuffs.

Users of the following ration examples should be aware that the suggested intake levels may not always be achieved in young kids and high-producing dairy goats, although intakes of more than 5 percent body weight have been reported (Haenlein, 1978b). Furthermore, it must be recognized that goats prefer selecting among and within various feed sources and that more forage is often needed in order to achieve the indicated net intake levels.

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