Reuters: Isaac Deka and his three exhausted cows cluster under a thorny acacia tree that provides little shelter from the midday sun. They are all that is left of a proud herd of 55 Borana cattle that were the wealth and livelihood of the 45-year-old Maasai pastoralist, his two wives and five children. “One of them is already lying down and it will not be able to stand again. By tomorrow or the day after I am not sure any of them will still be alive,” said Deka. Cattle are the …