A Kenyan researcher tries to get people to eat more insects.
Skimmed milk cow
A New Zealand biotech company has identified a pretty special mutation in a Friesian cow called Marge. Marge
produces a normal level of protein in her milk but substantially less fat, and the fat she does produce has much more unsaturated fat. She also produces milk with very high levels of omega3 oils.
The trait is heritable, and a commercial herd producing milk that is healthier and butter that is spreadable right out of the fridge is expected to be ready by 2011. The boffins at ViaLactia are looking for the gene involved.
People power
Here’s another potpourri, this one centred on local people’s perceptions of agricultural biodiversity. From the journal Livestock Science comes a paper looking at how traditional livestock keepers in Uganda select breeding bulls and cows among Ankole longhorn cattle. Another paper, this one from Crop Protection, discusses how Ethiopian farmers rank sorghum varieties with regard to their resistance to storage pests, and indeed what they do about such pests. And finally, from The Hindu newspaper, news of an initiative, to be launched on the International Day for Biological Diversity by the Kerala State Biodiversity Board, for a “people’s movement” to “prepare a database of all living organisms and traditional knowledge systems” in Kerala. The initiative is part of the state’s draft biodiversity strategy and action plan, which apparently includes consideration of agricultural biodiversity.
Globalization and parasite diversity
Toxoplasma gondii is a protozoan ((From H. Michael Kubisch. Photograph shows toxoplasma dividing into daughter cells. Image provided by Ke Hu and John Murray. DOI: 10.1371/journal.ppat.0020020.g001)) that can infect birds and mammals — although it can reproduce sexually only in domestic and wild cats. It has been estimated that about one in three human adults is infected, although the symptoms are usually minor. However, one particularly troublesome aspect of toxoplasma is its ability to cross the placenta from the mother and infect the growing fetus in utero. This can result in serious consequences in newborn children sometimes leading to heart and eye problems.
A recent study in the US has put an interesting spin on the genetic composition of toxoplasma. Toxoplasma DNA obtained from various chicken populations around the globe points to the existence of four major genetic strains, two found only in South America, one in the rest of the world — but not in South America — and a fourth population that seems to be ubiquitous.
The authors speculate that toxoplasma evolved initially in South America and then spread into Eurasia. The two populations were then separate for a long time. How this early migration might have happened is unclear; perhaps the parasite was carried by a bird. However, the spread of the Eurasian population back into North America, as well as the spread of the fourth population around the globe, could have had only one facilitator: us. At first the slave trade with its crammed and unsanitary ships possibly spread the parasite. Later, cargo ships containing agricultural goods might have given toxoplasma a lift to distant shores: in some locations the proportion of recent toxoplasma arrivals appears higher around port cities than further inland.
Yet another example of how human activity can shape evolutionary events, and contribute to diversity, in other species.
Livestock and carnivores
In many parts of Africa, carnivores such as lions and wild dogs still come into frequent conflict with pastoralist communities such as the Maasai because of their attacks on their cattle and goats. This naturally results in a tension between the aims – and indeed the practitioners – of wildlife conservation and of rural development that does no good to either camp. So it is interesting to read of a study which looked at how to foster co-existence between people, domesticated animals, and large predators. The paper identifies improvements to traditional livestock management, as well as other measures, that can contribute to wild carnivore conservation by minimizing the risk to livestock.