| Autor: |
L F P, Silva, R S, Hegarty, S J, Meale, D A F, Costa, M T, Fletcher |
| Rok vydání: |
2022 |
| Předmět: |
|
| Zdroj: |
animal. 16:100551 |
| ISSN: |
1751-7311 |
| DOI: |
10.1016/j.animal.2022.100551 |
| Popis: |
The difficulty in selecting cattle for higher feed and nitrogen use efficiency (NUE) is an important factor contributing to poor growth and reproductive performance in dry-tropics rangelands. Therefore, the objectives were to examine the cattle variation in retaining nitrogen in a protein-deficient diet and the natural abundance of stable isotopes in body tissues as a practical alternative for the detection of more efficient cattle. In experiment 1, feed efficiency parameters were determined in 89 Brahman steers fed a protein-limiting diet for 70 days, followed by 7 days in metabolism crates for total collection of urine and faeces and calculation of nitrogen retention and NUE. The diet-animal fractionation of nitrogen isotopes (Δ |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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