| Livestock and fish will be affected by the nanotechnology revolution. While the great hopes of nanomedicine are disease detection and new pharmaceuticals for humans, veterinary applications of nanotechnology may become the proving ground for untried and more controversial techniques - from nanocapsule vaccines to sex selection in breeding. Biochips - Current and Future Industry Applications Using biochips, biological samples such as blood, tissue and semen can be instantaneously analysed and manipulated. In fewer than five years, biochips have become a standard technology for genomics and drug discovery and they are now moving into commercial healthcare and food safety applications. What are Biochips (Microarrays) and How Are they Used to Study Genetic Sequences? A biochip (or microarray) is a device typically made of hundreds or thousands of short strands of artificial DNA deposited precisely on a silicon circuit. In DNA arrays, each DNA strand acts as a selective probe and when it binds to material in a sample (e.g. blood) an electrical signal is recorded. Rather like conducting a word search across a piece of text, the biochip is able to report back on found genetic sequences based on the DNA probes built into it. The best-known biochips are those produced by Affymetrix, the company that pioneered the technology and was first to produce a DNA chip that analyses an entire human genome on a single chip the size of a dime. Using Biochips in Biowarfare Agents or in Disease Detection Applications In addition to DNA biochips, there are other variations that detect minute quantities of proteins and chemicals in a sample, making them useful for detecting biowarfare agents or disease. Biochip analysis machines the size of an inkjet printer are commercially available from companies such as Agilent (Hewlett-Packard) and Motorola - each able to process up to 50 samples in around half an hour. Using Biochips for Disease Detection in Animals and for Tracing the Source of Foods Chips can be used for early disease detection in animals. Researchers at the University of Pretoria, for example, are developing biochips that will detect common diseases borne by ticks. Biochips can also be used to trace the source of food and feeds. For example, bioMérieux’s “FoodExpert-ID” chip rapidly tests feed to detect the presence of animal products from forty different species as a means to locate the source of pathogens - a response to public health threats such as avian flu and mad cow disease. How Biochips Might be Used in Animal Breeding to Remove Genetic Diseases One goal is to functionalise biochips for breeding purposes. With the mapping of the human genome behind them, geneticists are now rapidly sequencing the genomes of cattle, sheep, poultry, pig and other livestock hoping to identify gene sequences that relate to commercially valuable traits such as disease resistance and leanness of meat. By including probes for these traits on biochips, breeders will be able to speedily identify champion breeders and screen out genetic diseases. Microfluidics and Nanofluidics - What Are They and Which Industry Applications Might They Be Used In? Microfluidics is a newer technology platform on the same scale as biochips. Microfluidic and nanofluidic systems analyse by controlling the flow of liquids or gases through a series of tiny channels and valves, thereby sorting them, much as a computer circuit sorts data through wires and logic gates. Microfluidic channels, often etched into silicon, can be less than 100 nm wide. This allows them to handle biological materials such as DNA, proteins or cells in minute quantities - usually nano-liters or pico-liters (1000 times smaller than a nano-liter). Microfluidics not only enable very precise analysis, they also open up the potential for manipulation of living matter by mixing, separating and handling different components at the nanoscale. How Microfluidics Is Used in Livestock Breeding Microfluidics is being used in livestock breeding to physically sort sperm and eggs. Leader in this field is XY, Inc. of Colorado (USA), which is using a microfluidic technique called flow cytometry to segregate male and female sperm for sex selection. XY has successfully bred sex-selected horses, cattle, sheep and pigs and now provides its technology to commercial breeders. Nanotech startup Arryx, which has developed a new microfluidic system called MatRyx, uses a nanotechnique in which tiny laser tractor beams trap individual sperm and then sort them by weight. MatRyx can sort around 3,000 sperm per second, and aims for commercialisation in cattle breeding. “This way dairy farmers can have cows and beef farmers can have bulls that have more meat,” explains Arryx’s CEO Lewis Gruber. His goal is to produce a simple one-button sex sorter. How Microfluidic Devices Might be Used in Biomimetics Matthew Wheeler, University of Illinois professor of animal science, has gone one further in developing a microfluidic device that not only sorts sperm and eggs but also brings them together in a way that mimics the movement of natural reproduction and then handles the resulting embryo. According to Dr. Wheeler, such a technique would make mass production of embryos cheap, quick and reliable. He and his colleagues have started a spin-off company, Vitaelle, to commercialise this technology. |