Although recent historical studies about pastoral societies in East Africa have emphasized the issues of the diversities and transformations of these people, they rarely investigated the various aspects of livestock and veterinary administrations in colonial times. This article explores in detail the colonial rule in northern Kenya in the first half of the 20th century by examining these administrations. In the colonial era, northern Kenya was at first put on the periphery of the development. Their livestock was neither given veterinary services, nor permitted to export to the highland area. But after the introduction of poll taxes and the Second World War, the colonial administration had begun to realize the possibility that livestock can be utilized not only to contribute to the colonial economy, but to nurture modern mentalities among the pastoral people. And this possibility was attempted to be realized by the livestock and veterinary administrations.