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pay (WTP) values. The estimated implicit prices are computed using conditional2 parameter
estimates and the average values are reported in Table 4. Calculations of implicit prices from
conditional individual parameter estimates rather than from draws of population distribution
is reported by Hensher et al. (2005) to be advantageous since it produces behaviourally
realistic value estimates. Estimates of WTP for traits parameters indicate that a trypano-
tolerant bull or cow is valued at US$ 25 more than a trypano-susceptible one. According to
the household survey data, the average cost of treatment or control of trypanosomosis per year
per animal varies from US$ 6 to US$ 37 in Ethiopia while in Kenya it is an average of US$
36 in crop-livestock systems. This depends on the number of treatments per year, influenced
by the level of trypanosomosis challenge of the area. The implicit value for a bull with good
traction potential is a high value of US$ 58. Tano et al. (2003), also find high preference for
this trait, through highest rankings for bulls that are fit for traction in Burkina Faso. Fitness to
traction has a direct link to crop production in crop-livestock systems and is one of the main
reasons for keeping cattle.
Live-weight increase, which is associated with meat production, is valued at US$ 1.05
per Kg. This is close to the average slaughter weight of US$ 1.02 per Kg found in Scarpa et al.
(2003b) for a pastoral system in Kenya. An important attribute for cows is the ability to calve
every year instead of once in two years. This trait is valued at US$ 9.4 which is even higher
than the value of US$ 8.1 for a cow with high milk production. A bull that needs to be
watered only once in 2 days, used as a proxy for drought tolerance, is valued at US$ 7 more
than one that needs to be watered twice in a day. Water is an important constraint in the study
areas especially during the dry seasons; therefore a drought tolerant animal is relatively highly
valued by the cattle keepers.
2 The estimates are simulated conditioned on the choices observed to have been made by an individual.