Estimation of animal weight is critical in cattle production to assist in herd management and to estimate the value chain prices of the animals. There is a lack of tools for small-scale farmers and stakeholders to readily estimate cattle weight in communal livestock farming systems in South Africa. Models found in the literature cannot be easily adapted, as they may not be validated for the relevant breeds or may be too complex. The aim of this study was to build simple models based on heart girth and height to estimate the weight of Brahman and Nguni type cattle, the most common cattle raised by small-scale farmers in the lowveld of South Africa. Two models based on the heart girth performed well: weight0.263 = 0.022 x heart girth + 1.101 for Brahman type cattle andweight0.465 = 0.115 x heart girth – 3.578 for Nguni type cattle. When using these equations for herd management, correction to intercept by age should be added to estimate the sales value of an animal. Models based on height were less accurate, and models with two predictors had only a marginal improvement in accuracy while increasing the time for measurement collection.
"Experientia docet" - Experience is the best teacher