Page 1

1—
Introduction

The major nutrient requirements of sheep and the composition of typical diets that will supply those nutrients at specific stages of production are presented in Tables 1 and 2.

The values given are considered necessary for the levels of performance indicated in the tables for various stages of production and for the prevention of nutritional deficiencies.

When using these tables to determine feed rations, one should be aware of the following:

Variation among sheep affects the utilization of and need for nutrients.

Competition among sheep of different sizes, ages, and breeds may significantly affect the daily intake of an individual sheep, resulting in an excess intake by more-aggressive sheep and an inadequate intake by less-aggressive sheep.

Dry matter (DM) intake is an important consideration in formulating sheep rations. Severely restricted DM intake often results in a 5- to 10-fold increase in salt and mineral intake when minerals are offered free choice. Restricted DM intake may result in wool picking or defleecing of self or penmates.

Conversely, feeds excessively high in fiber or water may restrict nutrient intake. This is particularly a problem during late gestation in twin- and triplet-bearing ewes, early weaned lambs, and finishing lambs fed for maximum gain.

Performance level expected may differ from the levels indicated in the tables.

Interrelationships among nutrients may affect need.

Previous nutritional status of the sheep may influence requirements. Sheep previously fed carotene-deficient forage or sheep that are excessively thin or fat should be fed a diet different from sheep in average condition.

Level of intake may affect utilization of nutrients (e.g., high intake, in general, depresses digestibility).

Disease, parasites, environmental stress, and other less-obvious conditions may influence nutritional requirements.

Most of the values given in Tables 1 and 2 are based on research results. Some were determined by extrapolation from research data.

The nutrient values presented are for feedstuffs of average composition, digestibility, and quality. In special cases, adjustments in intake should be made. Amounts of feed refer to the amount actually consumed, not offered. Failure to account for wasted food may result in gross underfeeding.

Except for maintenance and early gestation diets, the amounts of dry matter indicated are near maximum without resulting in refusal. If higher levels or rates of production are sought via increased nutrient intake, an increase in the concentration of nutrients in the ration rather than an increase in the amount fed is necessary.



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Page 1 1— Introduction The major nutrient requirements of sheep and the composition of typical diets that will supply those nutrients at specific stages of production are presented in Tables 1 and 2. The values given are considered necessary for the levels of performance indicated in the tables for various stages of production and for the prevention of nutritional deficiencies. When using these tables to determine feed rations, one should be aware of the following: • Variation among sheep affects the utilization of and need for nutrients. • Competition among sheep of different sizes, ages, and breeds may significantly affect the daily intake of an individual sheep, resulting in an excess intake by more-aggressive sheep and an inadequate intake by less-aggressive sheep. • Dry matter (DM) intake is an important consideration in formulating sheep rations. Severely restricted DM intake often results in a 5- to 10-fold increase in salt and mineral intake when minerals are offered free choice. Restricted DM intake may result in wool picking or defleecing of self or penmates. Conversely, feeds excessively high in fiber or water may restrict nutrient intake. This is particularly a problem during late gestation in twin- and triplet-bearing ewes, early weaned lambs, and finishing lambs fed for maximum gain. • Performance level expected may differ from the levels indicated in the tables. • Interrelationships among nutrients may affect need. • Previous nutritional status of the sheep may influence requirements. Sheep previously fed carotene-deficient forage or sheep that are excessively thin or fat should be fed a diet different from sheep in average condition. • Level of intake may affect utilization of nutrients (e.g., high intake, in general, depresses digestibility). • Disease, parasites, environmental stress, and other less-obvious conditions may influence nutritional requirements. Most of the values given in Tables 1 and 2 are based on research results. Some were determined by extrapolation from research data. The nutrient values presented are for feedstuffs of average composition, digestibility, and quality. In special cases, adjustments in intake should be made. Amounts of feed refer to the amount actually consumed, not offered. Failure to account for wasted food may result in gross underfeeding. Except for maintenance and early gestation diets, the amounts of dry matter indicated are near maximum without resulting in refusal. If higher levels or rates of production are sought via increased nutrient intake, an increase in the concentration of nutrients in the ration rather than an increase in the amount fed is necessary.