A bio-economic model was developed to indicate Nyanza Dairy Goat Breeders Association, Meru Dairy Goat Breeders Association and Dairy Goat Association of Kenya representing Saanen, Toggenburg and Alpine breeds, respectively. Economic values were derived from the models with gross margin estimated per doe per year. On average, gross margin for the association keeping Saanen was more when compared with Alpine and Toggenburg breeds. Revenue, cost, and gross margin increased with the intensity of production. The greater production cost in the Saanen breed was most likely attributable to higher inputs to sustain higher output level compared to lower inputs in other breeds. The revenue was higher in the Saanen breed because of higher productivity and the price of outputs. The higher price of breeding bucks could indicate higher demand for Saanen breeding bucks than the supply. Alpine breed had the lowest revenue and negative gross margin, and this probably because of low the price of both milk and breeding bucks when compared with the other breeds.
Economic values for the three breeds were derived under two scenarios (fixed flock size and fixed feed), characterizing the dairy goat smallholder production systems in Kenya. In smallholder systems, animals are kept in small flocks with unstable numbers; therefore, assuming the fixed flock size may not be accurate. Under both scenarios, economic values were higher in fixed flock for the three breeds in all the selected traits. Although, Alpine had the lowest revenue, under fixed feed resources, the high economic values were recorded compared with the other breeds. This is contrary to the study of Bett et al. (2007) on Kenya dual-purpose goats that the economic values were higher under fixed feed resource situation.
In dairy production systems, milk yield is positively associated with growth and survival of kids. The number of animals available for replacement and sale may therefore be as a result of milk yield improvement. Bennison et al. (1997) reported the significance of animal survival in connection to milk and meat production in a production system. In this study, under both scenarios, negative economic values were derived for milk yield in Alpine breed, implying that genetic improvement of milk yield would result in a decrease in the gross margin of Alpine production. It is worth noting, that farmers who kept Alpine breed changed their breeding objective from milk yield to producing breeding animals according to Waineina et al. (2021). Farmers changing breeding objective has been reported before, in that farmers might perceive some traits found to be very important in the breeding program proposal as of secondary significance (Bett et al., 2007). Survival rate PrSr, PoSR, and DoSR traits recorded high economic values in both situations. This is an indication that genetic improvement on those traits would influence positively on profitability of Alpine breed production.
In this study, a higher survival rate would result in a higher revenue from the sale of milk, breeding bucklings, surplus does after selection for replacement, and cull does. This has been reported in other species (dairy cattle), that improving the survival rate has a positive impact in milk revenue per cow from a good number of mature cows and the sale of surplus heifers (Kahi & Nitter, 2004). An increase by one unit in genetic merit of the survival traits could lead to more profit per doe per year. In all the breeds, improvement of survival in early stage in life (PrSr trait) resulted in higher profits than the same improvement in survival later in life (DoSR trait). The presence of a large population of young animals in all the breeds could lead to an increase of profit per doe per year through the sale of more breeding animals.
The results of this study indicate that the developed bio-economic model was able to estimate the gross margin of Saanen, Toggenburg and Alpine breeds representing the dairy goat breeders’ associations reared under semi-intensive production system. The model derived the economic values per unit increase due to one unit change in the genetic merit of the selected trait keeping the other traits constant. All of the selected traits with positive economic value suggest a unit increase in genetic worth of these traits. Therefore, all those traits can be included in the breeding programme for the improvement of Saanen, Alpine, and Toggenburg breeds reared under semi-intensive production system in the tropics.