Experimental breeding

Experimental Breeding a procedure daling back several centuries, requires considerable time and patience because the animals or plants studied must experience a number of lifetimes (generations). Statistical methods typify ihis kind of genetic research. 

Pedigree Analysis, an approach widely used where experimental breeding is not practical. Pedigrees show the inheritance of specific Iraits. which can be traced, in all of lhe members of a family line. Human pedigrees have been very useful in terms of tracing the familial aspects of certain diseases. One of the first diseases so traced was hemophilia. Stock... 

Sunflower oil is a rich source of vitamin E. It contains, on average, 400-700 pg/g total tocopherols (Van Niekerk and Burger, 1985 Eitenmiller, 1997 Kamal-Eldin and Andersson, 1997). Total tocopherol concentration of 66 experimental breeding lines with commodity-type fatty acid compositions was 982 27 pg/g, of which >99% was a-tocopherol. a-Tocopherol was present in some lines as a minor component. The tocopherol compositions of breeding lines with adjusted fatty acid compositions were similar (Dolde et al., 1999). 

H. Mellanby (75) studied the effect of maternal dietary deficiencj of vitamin A on dental tissues in rats. From the age of 3 to 4 weeks female rats were fed the deficient diet for different periods before experimental breeding was begun. The young of mothers who had been on the diet 24 to 26 weeks prior to the birth of their litters showed gross dental abnormalities soon after birth. Their incisor teeth were veiy abnormal in shape, the teeth were retarded in development and the molars were misshapen. There were also changes in the mothers teeth but in all experiments the abnormalities were more pronounced in the yoimg than in their mothers. 

The PCR technique is very useful during all stages of the research and development of biotech crops. PCR analysis is used for gene discovery, event selection, screening, transformant identification, line selection and plant breeding. Quantitative real-time PCR is used to determine the number of transgene copies inserted in experimental... 

The variety of breeding patterns displayed by the American and Australian metatheria and the lack of comparative experimentation hampers general conclusions on any fundamental division from eutherian mammals. 

Mice are a favorite experimental animal for scientists interested in mammalian pheromones they are easy to breed they have well-defined genetic backgrounds and they rely on pheromones in a number of ways. My former colleague at Indiana University, Milos Novomy, did the first definitive work on mammalian pheromones in the house mouse. He has identified a number of primer pheromones in the urine of male mice that accelerate puberty and induce estrus in female mice. ... 

In summary. Directive 86/609/EEC requires the premises in which animal research is undertaken and persons conducting such research, to be subject to local registration and inspection and imposes limitations upon the breeding and supply of experimental animals. There are specific provisions regarding the care of experimental animals, including, for example, minimum caging and temperature requirements. As a Directive, 86/609/EEC required implementation... 

Moreover, their housing is less space- and cost-intensive, which predestines them for large mutagenesis screens, selective breeding and quantitative trait loci studies. Although rats are principally indispensable for behavioural experiments, mice will clearly dominate the experimental analysis of learning and memory for the next decade. 

Such studies should be very precise. Products should preferably be grown or raised on experimental farms where production conditions can be controlled (Harker 2004), particularly when several combinations or options within a production system are tested. Another useful approach is the paired comparison of similar, neighbouring farms producing the same cultivar or breed under the two different production regimes. Studies need to include some assessment of the product to be consumed, including (if relevant) the preparation taking place in the home. 

Breed, M.D. (1998). Chemical cues in kin recognition criteria for identification, experimental approaches, and the honey bee as an example. In Pheromone Communication in Social Insects. Ants, Wasps, Bees and Termites, ed. R. K. Vander Meer, M.D. Breed, K.E. Espelie and M. L. Winston. New York Westview Press, pp. 57-78. 

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