The unique resistance and resilience of the Nigerian West African Dwarf goat to gastrointestinal nematode infections

<p>Abstract</p> <p>Background</p> <p>West African Dwarf (WAD) goats serve an important role in the rural village economy of West Africa, especially among small-holder livestock owners. They have been shown to be trypanotolerant and to resist infections with <it>Haemonchus contortus </it>more effectively than any other known breed of goat.</p> <p>Methods</p> <p>In this paper we review what is known about the origins of this goat breed, explain its economic importance in rural West Africa and review the current status of our knowledge about its ability to resist parasitic infections.</p> <p>Conclusions</p> <p>We suggest that its unique capacity to show both trypanotolerance and resistance to gastrointestinal (GI) nematode infections is immunologically based and genetically endowed, and that knowledge of the underlying genes could be exploited to improve the capacity of more productive wool and milk producing, but GI nematode susceptible, breeds of goats to resist infection, without recourse to anthelmintics. Either conventional breeding allowing introgression of resistance alleles into susceptible breeds, or transgenesis could be exploited for this purpose. Appropriate legal protection of the resistance alleles of WAD goats might provide a much needed source of revenue for the countries in West Africa where the WAD goats exist and where currently living standards among rural populations are among the lowest in the world.</p

History of orchid propagation: A mirror of the history of biotechnology

Part I Orchid seeds are nearly microscopic in size. Because of that, many fanciful theories were proposed for the origin of orchids. Almost 400 years separate the time when orchid seeds were seen for the first time and the development of a practical asymbiotic method for their germination. The seeds were first observed and drawn during the sixteenth century. Seedlings were first described and illustrated in 1804. The association between orchid and fungi was observed as early as 1824, while the requirement for mycorrhiza for seed germination was established in 1899. An asymbiotic method for orchid seed germination was developed in 1921. After Knudson's media B and C were formulated, orchids growing and hybridization became widespread. Hybrids which early growers may not have even imagined became possible. Part II A commonly held view is that Prof. Georges Morel is the sole discoverer of orchid micropropagation and that he was the first to culture an orchid shoot tip in 1960. In fact, the first in vitro orchid propagation was carried out by Dr. Gavino Rotor in 1949. Hans Thomale was the first to culture an orchid shoot tip in 1956. The methods used by Morel to culture his shoot tips were developed by others many years before he adapted them to orchids. This review also traces the history of several techniques, additives, and peculiarities (agitated liquid cultures, coconut water, banana pulp, a patent and what appears to be an empty claim) which are associated with orchid micropropagation. A summary of plant hormone history is also outlined because micropropagation could not have been developed without phytohormones. © 2009 Korean Society for Plant Biotechnology and Springer