| animalagriculture.org | The National Institute for Animal Agriculture |
| rsnz.govt.nz | Rsnz/publishing/nz Jnl Of Agricultural Research |
| nap.edu | Nat'l Academies Press, Microlivestock: (1991), Table Of Contents |
| meatnet.nl | Meatnet by Ecceamst |
| okstate.edu | Breeds of Livestock : Oklahoma State University |
| admin.ch | Agroscope Liebefeld-Posieux |
| nzsap.org.nz | New Zealand Society of Animal Production |
| wau.nl | Animal Production Systems Group |
| sasas.co.za | South African Society for Animal Science |
| umn.edu | University of Minnesota Extension - Livestock Systems |
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