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- Department of Agronomy, University of Fort Hare
- This work was made possible by grants from the following institutions, whose generosity is gratefully acknowledged: Chairman's fund of Anglo American & De Beers Ltd Development Bank of Southern Africa The Department of Agriculture and Forestry of the Republic of Ciskei. The following persons rendered invaluable assistance: Messrs J G Raats and J W A Stead of the Department of Animal Science of the Faculty of Agriculture for chemical analysis. Mr M N Austin of the Department Agronomy for statistical analysis of heat budgeting. Messrs O K Awuso‐Aduomi and W Seti for technical assistance.