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This paper discusses the effects of severe nutritional restriction, both pre- and post-weaning, on development of skeletal muscle in food animals. Given recent predictions about growth in demand for muscle-foods in developing countries, the global community will need to face the food-feed dilemma, and balance efficiency of production against the quality-of-life aspects of local livestock husbandry. It is likely that production animals will be grown in successively more marginal environments and at higher stocking rates on unimproved pastures. Understanding the nutritional limits to animal growth at the level of muscle gene networks will help us find optima for nutrition, growth rate and meat yield. Genomic approaches give us unprecedented capacity to map the networks of control under nutritionally restricted conditions, though the challenges remain of identifying steps that regulate substrate flux. The paper describes some approaches currently being taken to understanding muscle development, and concludes that the genes contributing to two ruminant phenotypes should be mapped and characterized. These are: the capacity to depress metabolic rate in response to nutritional restriction; and the capacity to exhibit compensatory growth after restriction is relieved.

Currently there is a shortage of food and potable water in many developing countries. Superimposed upon this critical situation, because of the increasing urban wealth in these countries, there is a strong trend of increased consumption of meat, and pork in particular. The consequence of this trend will be increased agricultural pollution, resulting not only from greater use of chemical fertilizer, but also from manure spread on land as fertilizer that may enter freshwater and marine ecosystems causing extensive eutrophication and decreased water quality. The application of transgenic technologies to improve the digestive efficiency and survival of food animals, and simultaneously decreasing their environmental impact is seen as an opportunity to enhance sustainability of animal agriculture without continued capital inputs. Transgenes expressed in pigs that have potential include, for example, genes coding for phytase, lactalbumin and lactoferrin. At the University of Guelph, Escherichia coli phytase has been expressed in the salivary glands of the pig. Selected lines of these pigs utilize plant phytate phosphorus efficiently as a source of phosphorus and excrete faecal material with more than a 60 percent reduction in phosphorus content. Because of their capacity to utilize plant phytate phosphorus and to produce less polluting manure they have a valuable trait that will contribute to enhanced sustainability of pork production in developing countries, where there is less access to either high quality phosphate supplement or phytase enzyme to include in the diet. Issues that require continued consideration as a prelude to the introduction of transgenic animals into developing countries include food and environmental safety, and consumer acceptance of meat products from genetically modified animals.

Livestock are vital to subsistence farming and sustainable livelihood in most developing countries. Of India’s population of one billion people, more than 70 percent live in the rural areas. India also has more than 30 percent of the world’s bovine population. This has resulted in not only egalitarian ownership of cattle, but also in an almost inseparable cultural and symbiotic relationship between rural families and their farm animals, particularly large ruminants. It is against this scenario that the ethical, social and environmental issues of gene-based technologies need to be carefully evaluated. The use of transgenic cows with modified milk composition or for any other purpose has little economic benefit in a system of “production by masses”, as typifies India and a few other developing countries, compared with “mass production” systems in developed countries. Rather, the use of rDNA technology for developing drought-resistant fodder and forage crops is likely to bring immediate relief to most regions. Cattle, particularly in India, have poor quality feeds and this results in poor nutrition, with production of large amounts of methane. Immunocastration through biotechnological means would also be advantageous. Developing countries like India need sustainable livelihood security, and, in this regard, gene-based technologies in animal agriculture seem more to raise ethical, social and environmental concerns, rather than being likely to transform “subsistence farming” into vibrant agribusiness. Ethical issues concerning animal welfare, rights and integrity are also discussed, in addition to social, environmental and economic issues.

Intellectual property rights (IPR) are legal and institutional devices to protect creations of the mind. With respect to gene-based innovation, the most significant IPR is patents. Appropriate patent regimes have the potential to foster innovation in animal biotechnology and the transfer of gene-based technologies. Inappropriate patent systems may be counter-productive. Indeed, many critics are doubtful that the current international patent standards, based as they are on a combination of the United States of America’ and European regimes, can help countries that lack the capacity to do much life science and biotechnology research to become more innovative or contribute to the acquisition, absorption and, where desirable, the adaptation of new gene-based technologies from outside. Present legislation in Europe, North America and internationally is considered, together with the controversies and important policy questions for developing countries, and the choices facing countries seeking to enhance their scientific and technological capacities in these areas.

There has been rapid uptake of GM crops, with widespread use in livestock production systems. The concept of substantial equivalence as the starting point for the safety assessment of GM crops is discussed, together with the role of compositional and nutritional equivalence. Concerns have been expressed as to the fate of transgenic DNA and the expressed protein, and the safety of milk, meat and eggs derived from animals receiving diets containing GM feeds, and the effects of feed processing, conservation and nutrient digestion on the fate of transgenic DNA and proteins, are presented. Their presence in milk, meat and eggs has never been established in any study to date. There is no evidence to suggest that livestock products from animals receiving GM feed ingredients are anything other than as safe as those produced from conventional feeds. Furthermore, although hypothetically possible, horizontal gene transfer between transgenic DNA and micro-organisms either in the digestive tract of livestock or in the soil has not been established under natural conditions.

Development of an effective regulatory system for genetically engineered animals and their products has been the subject of increasing discussion among researchers, industry and policy developers, as well as the public. Since transgenesis and cloning are relatively new scientific techniques, transgenic animals are new organisms for which there is limited information. The issues associated with the regulation and biosafety of transgenic animals pertain to environmental impact, human food safety, animal health and welfare, trade and ethics. To regulate this new and powerful technology predicated on limited background information is a challenge not only for the regulators, but also for the developers of such animals, who strive to prove that the animals are safe and merit bio-equivalency to their conventional counterparts. In principle, an effective regulatory sieve should permit safe products while forming a formidable barrier for those assessed of posing an unacceptable risk. Adoption of transgenic technology for use in agriculture will depend upon various factors that range from perceived benefits for humans and animals, to safe propagation, animal welfare considerations and integrity of species, as well as effects on bio-diversity. A regulatory framework designed to address the concerns connected with the environmental release of transgenic animals needs to also take into account the ability of genetically modified animals to survive and compete with conventional populations. Regulatory initiatives for biotechnology-derived animals and their products should ensure high standards for human and animal health; a sound scientific basis for evaluation; transparency and public involvement; and maintenance of genetic diversity. Feeds obtained by use of biotechnology have to be evaluated for animal and human safety by using parameters that define their molecular characterization, nutritional qualities and toxicological aspects, while veterinary biologics derived from biotechnology must be shown to be pure, potent, safe and effective when used according to label recommendations. The Canadian regulatory system relies on the “precautionary principle” in its approach to regulate the “product” instead of the “process”. The regulatory framework captures transgenic animals under the Canadian Environmental Protection Act (CEPA). Food from transgenic animals is assessed for safety by Health Canada under its Novel Foods Regulations of the Food and Drugs Act . Feed containing any genetically modified organism is considered Novel Feed under the Feeds Act and Regulations . The regulation of veterinary biologics, in an effort to prevent and diagnose infectious diseases of animals, relies on effective science-based regulatory controls under the Health of Animals Act and Regulations . The Canadian system of regulation for feeds, veterinary biologics and transgenic animals could be useful to developing countries in the process of establishing an effective framework for new regulations.

Escherichia coli isolates from 131 raw chicken meat samples were tested for susceptibility to 12 antibiotics. Plasmids were isolated from many samples and their DNA molecular weight calculated. An 81.7% plasmid occurrence rate was observed among the isolates, ranging from 0 to 8 in number and with sizes from 1.2 to 118.6 MDa. Plasmids were detected in 93.8% of E. coli isolates resistant to all 12 antibiotics, and in 90.5% of E. coli isolates resistant to 11. Three (2.8%) isolates harboured 8 plasmids and were resistant to all 12 antibiotics. Antibiotic resistant genes in bacteria are usually carried in extrachromosomal DNA and it is postulated that E. coli with a high number of plasmids possesses wider resistance to antibiotics.

The identification of Salmonella spp. from poultry meat was studied by comparing bacterial detection using the Gene-Trak colorimetric hybridization method, a PCR amplification kit and an Enzyme Linked Immunosorbent Assay (ELISA), and these methods were compared with the conventional methodology proposed by the United States Food and Drug Administration (US FDA) for detection of Salmonella in food samples. Forty positive and negative samples were studied. The three methods yielded similar results with levels of Salmonella greater than 10 CFU per sample, even when the samples were highly contaminated with competing bacteria. In contrast, 20 CFU of seed inoculum per sample was the lowest level of Salmonella detectable with all three methods and the standard culture method. The detection limits of the PCR and ELISA assays were 5 CFU/g after enrichment at 37°C for 6 and 9 hours, respectively. Compared with conventional bacteriology, all three methods here demonstrated high sensitivity and specificity for Salmonella.

Transmissible spongiform encephalopathies (TSE) include bovine spongiform encephalopathy (BSE), scrapie in sheep and Creutzfeldt-Jakob disease (CJD) in humans. A new CJD variant (nvCJD) is believed to be related to consumption of meat from BSE cattle. In TSE individuals, prion proteins (PrP) with approximately 250 amino acids convert to the pathogenic prion PrP^Sc, leading to a dysfunction of the central neural system. Research elsewhere with mice has indicated a possible genetic engineering approach to the introduction of BSE resistance: individuals with amino acid substitutions at positions 167 or 218, inoculated with a pathogenic prion protein, did not support PrP^Sc replication. This raises the possibility of producing prion-resistant cattle with a single PrP amino acid substitution. Since prion-resistant animals might still harbour acquired prion infectivity, regulatory assessment of the engineered animals would need to ascertain that such possible ‘carriers’ do not result in a threat to animal and human health.

One of the ironies of the current debate in New Zealand about genetic modification is that it highlights the age-old conflict between science and religion, and in so doing demonstrates that modern society is still caught in the dilemma posed by these two views of the world. Two case studies are presented that demonstrate the distance between proponents and opponents of genetic modification (GM), and the difficulty of resolution within the secular-based framework of quantitative risk assessment applied by the Environmental Risk Management Authority (ERMA) and decision-making committees. Alternative frameworks suggested by Maori are beginning to emerge, and along with the results of several government-funded research projects in this area, should make a valuable contribution to a new framework that more equitably incorporates the fundamental principles of both knowledge systems. If this aim is achieved, it will be of considerable interest to other indigenous peoples in the world who are also faced with real and perceived threats to their cultural beliefs and values originating from new biotechnologies