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The potential of open learning in animal breeding.

Animal breeding education is presently facing many challenges. These include rapid changes in breeding knowledge and technology, resource and funding restrictions, and altering demographics of the learner and the animal breeding industry. These challenges can be met via an open learning educational format. This nontraditional approach is based on the needs of individual learners, not the interests of the teacher or the institution. An important feature of open learning is its appropriateness for the professional development audience. Delivery methods include interactive distance courses on the Web, computer-assisted learning, and team-based study. The Canadian dairy breeding industry has expressed the need for ongoing professional development to understand and adopt new animal breeding technologies. The University of Guelph responded by delivering a series of animal breeding short courses (Executive Certificate Program in Animal Breeding) to industry decision makers in 1997. A version modified specifically for farmers and breeding industry personnel was offered in 1998. Through the collaboration of experts from various agricultural institutions and the use of a learner-centered format, this professional development initiative was a pedagogical and financial success. This paper describes how the open learning approach differs from traditional university teaching. Using the University of Guelph example in animal breeding professional development, the framework for a successful open learning program will be examined. The best practices for effective adult education will also be identified and discussed within this case study.

Adult↗

Interrelationships between recent developments in molecular genetics and cytogenetics and animal breeding.

Animal breeding traditionally has entailed devising means to apply quantitative and population genetic theory to increase productive capacity of livestock. A highly developed and successful industry has been built on foundations established by academic animal breeders. Recent developments in related sciences such as reproductive biology, molecular biology, cellular biology, and cytogenetics offer prospects for the emergence of a number of methodologies that might usefully be applied to animal breeding. Scientists engaged in development of the newer technologies are not wholly familiar with the livestock industry, its breeding structure, its objectives, its institutions or its peculiarities. Animal breeders, however, are not fully cognizant of the scientific advances being made in related fields, their potential for development and application or their limitations, and therefore, animal breeders have not seriously thought about how they might be integrated most usefully and efficaciously into the animal breeding enterprise. A collaboration is needed in which the laboratory scientists produce new ideas, products, and methods and the animal breeders--using system analysis, simulation procedures, and laboratory animal and livestock breeding tests--help make rational choices, partially direct work of the laboratory scientists, help the industry integrate new methods, and monitor the extent of success of adapted innovations.

Animal Husbandry↗

Genomics meets ethology: a new route to understanding domestication, behavior, and sustainability in animal breeding.

Animal behavior is a central part of animal welfare, a keystone in sustainable animal breeding. During domestication, animals have adapted with respect to behavior and an array of other traits. We compared the behavior of junglefowl and White Leghorn layers, selected for egg production (and indirectly for growth). Jungle-fowl had a more active behavior in social, exploratory, anti-predatory, and feeding tests. A genome scan for Quantitative Trait Loci (QTLs) in a junglefowl x White Leghorn intercross revealed several significant or suggestive QTLs for different traits. Some production QTLs coincided with QTLs for behavior, suggesting that pleiotropic effects may be important for the development of domestication phenotypes. One gene has been located, which has a strong effect on the risk of being a victim of feather pecking, a detrimental behavior disorder. Modern genomics paired with analysis of behavior may help in designing more sustainable and robust breeding in the future.

Animals↗

Chronic lymphocytic leukaemias and non-Hodgkin's lymphomas by histological type in farming-animal breeding workers: a population case-control study based on a priori exposure matrices.

OBJECTIVES: A population based case-control study was conducted in a highly agricultural area in Italy to investigate the association between chronic lymphocytic leukaemias (CLLs) and non-Hodgkin's lymphomas (NHLs), and subtypes, and exposure to pesticides in farming-animal breeding workers. METHODS: 187 cases of CLLs and NHLs and 977 population controls were interviewed on medical, residential, family, and occupational history. Detailed information was collected about cultivated crops and animals bred from subjects who worked in farming and animal breeding. Information on crop diseases and pesticides used (and their quantity and duration) was also obtained. A priori job-exposure matrices were applied when a crop disease was reported, estimating the most probable pesticide and, when possible, an estimate of the cumulative dose. Odds ratios (ORs) were calculated by unconditional logistic analysis with adjustment for relevant confounders in farmers who bred animals and in farmers alone, for the main crops, types of animals, and pesticides categories. First recall and then the matrices were used for defining exposure, as it affected CLLs and NHLs and then separately on CLLs and low grade NHLs. Finally, the dose-response was investigated for those pesticides which had shown some association. RESULTS: No variable under study was associated with work in farming alone. In farming and animal breeding, no crop or animal showed an association with CLLs and NHLs when adjusted by exposure during childhood to farming and animal breeding (an indicator of life in a farming and animal breeding environment before the age of 13, which behaved as an independent risk variable). A non-significant association was found with stannates, arsenates, phosphates, and dichloro-diphenyl-trichloroethane (DDT) based on recall, and for stannates, arsenates, and DDT after the application of the matrices. When CLLs together with low grade NHLs were considered, the association with insecticides in general, carbamates, and phosphates became significant according to personal recall (ORs and 95% confidence intervals (95% CIs) 2.46, 1.07-5.63; 3.08, 1.05-9.00; 2.97, 1.28-6.91, respectively). The application of the matrices also showed a risk of borderline significance for stannates and dithiocarbamates. A significant dose-response effect was found for phosphates (for logarithmic unit increase, OR 1.17, 95% CI 1.00-1.57); a strong trend for stannates and carbamates did not reach significance. CONCLUSION: The association of CLLs and NHLs with work in farming-animal breeding is partially explained by exposure to pesticides-namely insecticides (carbamates, phosphates, and DDT) and stannates-possibly related to their use in animal breeding. The association is limited to cases of CLL and low grade NHL. The independent effect of the variable exposure during childhood suggests that early exposures, including possible contact with animals, may play a part in the pathogenic process of these neoplasms.

Animal Husbandry↗

A computational approach to animal breeding.

We propose a computational model of mating strategies for controlled animal breeding programs. A mating strategy in a controlled breeding program is a heuristic with some optimization criteria as a goal. Thus, it is appropriate to use the computational tools available for analysis of optimization heuristics. In this paper, we propose the first discrete model of the controlled animal breeding problem and analyse heuristics for two possible objectives: (1) breeding for maximum diversity and (2) breeding a target individual. These two goals are representative of conservation biology and agricultural livestock management, respectively. We evaluate several mating strategies and provide upper and lower bounds for the expected number of matings. While the population parameters may vary and can change the actual number of matings for a particular strategy, the order of magnitude of the number of expected matings and the relative competitiveness of the mating heuristics remains the same. Thus, our simple discrete model of the animal breeding problem provides a novel viable and robust approach to designing and comparing breeding strategies in captive populations.

Algorithms↗

The Bayesian controversy in animal breeding.

Frequentist and Bayesian approaches to scientific inference in animal breeding are discussed. Routine methods in animal breeding (selection index, BLUP, ML, REML) are presented under the hypotheses of both schools of inference, and their properties are examined in both cases. The Bayesian approach is discussed in cases in which prior information is available, prior information is available under certain hypotheses, prior information is vague, and there is no prior information. Bayesian prediction of genetic values and genetic parameters are presented. Finally, the frequentist and Bayesian approaches are compared from a theoretical and a practical point of view. Some problems for which Bayesian methods can be particularly useful are discussed. Both Bayesian and frequentist schools of inference are established, and now neither of them has operational difficulties, with the exception of some complex cases. There is software available to analyze a large variety of problems from either point of view. The choice of one school or the other should be related to whether there are solutions in one school that the other does not offer, to how easily the problems are solved, and to how comfortable scientists feel with the way they convey their results.

Animals↗

Chronic lymphocytic leukaemias and non-Hodgkin's lymphomas by histological type in farming-animal breeding workers: a population case-control study based on job titles.

OBJECTIVES: A population based case-control study was conducted in a highly agricultural area in the north east of Italy to evaluate the association between farming and animal breeding and the risk of developing non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL). METHODS: Occupational histories and other data were collected by personal interview on 164 NHLs, 23 CLLs, diagnosed in 1988-90, and on 977 controls. This paper only reports the results of the analysis relative to the coding of job titles through the modified International Labour Office (ILO) classification. Estimates of odds ratios (ORs) for occupational variables were calculated, after adjustment for sex, age, altitude of municipality, first degree familiarity, and previous Herpes zoster infection. RESULTS: From the analysis of the most frequent occupational categories, no occupation showed a significantly high risk. When the two job titles farmers only and farmer-breeders who are also involved in animal breeding are classified within the extremely varied occupation of agriculture or animal-breeding or fishing, a high risk for NHLs and CLLs is seen in the farmer-breeders (OR 1.79, 95% CI 1.22 - 2.63). Analyses according to histological type show that the risks are concentrated in CLLs and in low grade NHLs. No effect or trend by period at work or duration of employment in farming and animal breeding was found. CONCLUSION: Subjects working in agriculture associated with animal breeding are at high risk of NHL/CLLs, particularly CLLs and low grade NHLs. This finding could be related to the use of chemicals in agriculture or to exposure to animal transmitted diseases or specific chemicals used in animal breeding.

Adolescent↗

[The native domestic animal breeds of Japan].

During the last decades some domestic animal breeds have spread to all parts of the world. In general, consideration is given to these breeds only; on the other hand, autochthonous breeds of various countries are hardly known. These, however, can be valuable gene-reserves, and moreover, they represent a significant cultural value. In Japan there are several domestic animal breeds which are almost unknown in Central Europe. They are presented verbally and by means of illustration, and their breeding history is dealt with as well. The purpose of this study is to point out the importance of these breeds within the country and to make clear the extent of the danger of their extinction.

Animals↗

[Mendelism in animal breeding as developed by professor Leopold Frateur, Louvain (1877-1946)].

Educated as a veterinarian at Cureghem, Leopold Frateur started his scientific career in 1899 as a professor at the Faculty of Sciences of the Catholic University of Louvain, Belgium, in charge of the course in zootechnology. After a study tour to zootechnical institutes and centres of animal breeding in Europe he was invited by the governmental department of Agriculture and the Belgian Society of Zootechnology to investigate the relevance of the Mendelian laws of heredity for the improvement of cattle breeding. In the early years of the century, Frateur conducted field research in order to determine the characteristics of the cattle breeds in Belgium. In 1908 Frateur founded the Institute of Animal Husbandry at his university. Here he worked out his programme of experimental genetics until his retirement in 1936. The last six years of his professorship he teached also agricultural economics in the Faculty of Economical Sciences. In Frateur's experimental research the following main lines can be distinguished: 1) The analysis of simple and complex hereditary factors in cattle, rabbits and poultry; 2) The study of qualitative and quantitative characteristics of importance for the improvement of animal breeds; 3) The synthesis of genetic factors from different stock in order to obtain higher yielding breeds with stable characteristics; 4) Theoretical study of the relationship between genotype and phenotype and the influence of environment factors; 5) Theoretical exploration of the issue of variability and modification of newly formed characteristics; 6) Research leading to an explanation of telegony and atavism; 7) The formulation of a theory on the creation of new breeds in domestic animals and plants, and the relation between breed and species. Also he was responding to topical needs, e.g. he determined the causal factor of pullorum epidemic in chicken farming, or he investigated the hereditary resistance against diphteric infection amongst chickens. Frateur took the theoretical knowledge on heredity as the starting point for practical application in cattle breeding. During and right after W. W. I. he stated that the current scientific knowledge is enough advanced to consider the start of a large breeding programme for the improvement of cattle livestock. In order to realise this reinstatement Frateur received important support from the authorities (Royal Decree, August 1919). From then onwards he focussed his efforts on the realisation of a national framework for improvement of cattle livestock, in collaboration with regional centres and societies for animal selection, breeding and production. Later he also started programmes for the improvement of chicken and pig breeding, again in a joint effort with official consultants and members of breeding societies. He was not only the architect of these programmes, providing the necessary scientific and technical guidance, but he had also a chair in the governing bodies, supervising the execution and control of the breeding programmes. In order to draw a picture of the research community engaged in animal breeding during the first decennia of the 20th century Frateur's contacts through study tours, congresses and learned societies are investigated. The life and work of Frateur is described by the author in two volumes, published in 1999. The second volume consists of a reprint of 50 selected papers on animal breeding.

Animals, Genetically Modified↗

[The problems of breeding spotted rabbits. 3. Variability of the pigmentation grade, ganglionic intestinal wall supply, relationship to pathogenesis--animal breeding and animal welfare aspects].

In a total of 128 animals of the German Giant Spot und the English Spot Breed grade of pigmentation and spotting pattern were investigated by photography and planimetry. A clear cut binary distribution, representing homozygous (KK) or heterozygous spot rabbits (Kk), and a strong bilateral concordance was found as well as a broad variance within both genotypical groups. Thus only a small percentage of animals bred can be compatible with mandatory fancy breed standards. Measurements of intestinal layers and neural components in well pigmented and depigmented individuals revealed an enhancement of these histological structures but a relative hypoganglionosis in distal parts of the gut in animals with predisposition to megacolon (KK, so-called chaplins). It is not yet clear whether this is symptomatic or of primary pathogenetic relevance. There were no pleiotropic deleterious effects of the K-allele in heterozygous rabbits and no correlations between the degree of depigmentation and the severity of symptoms in homozygous spotted ones, thus indicating a mode of inheritance by an incompletely dominant gene K, acting as or being linked to a recessive semilethal when homozygous. A change in breeders' attitude and breeding practices is mandatory because neither the permanent elimination of animals not "fitting" a fancy standard nor the continuous production of defective genotypes is legal.

Animals↗

Definition of animal breeding goals for sustainable production systems.

What we do is determined by the way we "view" a complex issue and what sample of issues or events we choose to deal with. In this paper, a model based on a communal, cultural, or people-centered worldview, informed by a subjective epistemology and a holistic ontology, is considered. Definitions and interpretations of sustainable agriculture are reviewed. Common elements in published definitions of sustainable agriculture and animal production among those who seek long-term and equitable solutions for food production are resource efficiency, profitability, productivity, environmental soundness, biodiversity, social viability, and ethical aspects. Possible characteristics of future sustainable production systems and further development are presented. The impact of these characteristics on animal breeding goals is reviewed. The need for long-term biologically, ecologically, and sociologically sound breeding goals is emphasized, because animal breeding determined only by short-term market forces leads to unwanted side effects. Hence, a procedure for defining animal breeding goals with ethical priorities and weighing of market and non-market values is suggested. Implementation of non-market as well as market economic trait values in the aggregate genotype, as suggested, may allow for breeding programs that contribute to sustainable production systems. Examples of breeding goals in salmon, cattle, and pigs are given, and the resulting genetic responses are evaluated with respect to economic profit (or costs) and other criteria of sustainability. Important prerequisites for breeding programs for sustainable production are appropriate governmental policies, awareness of our way of thinking, and a more communal worldview informed by a subjective epistemology and a holistic ontology.

Animal Husbandry↗

Prospects for human reproductive medicine--applications of experimental techniques used in farm animal breeding.

Can assisted reproduction techniques performed in farm animal breeding be considered as future methods in human sterility treatment? The answer is no because, at the moment, the goals in human and animal reproduction are totally different. The methods that scientists are using or developing for farm animals are either without any therapeutic value for humans or they are forbidden by the German Embryo Protection Law. However, there are a few aspects which might be of value in the future of human assisted reproduction. The technique of in vitro maturation of immature follicles and oocytes, which is prerequisite in animal in vitro fertilization the female gamete pool after slaughter, might be used to obtain mature human oocytes from unstimulated cycles in women who do not respond to hormonal stimulation. Further more, it can be used in cancer patients to save their oocytes shortly before cancer treatment. Although still forbidden at the moment by the Embryo Protection Law, it is possible that the pre-implantation diagnosis of early embryos by the polymerase chain reaction technique after blastomere biopsy will become a valuable tool in preventing genome aberration in future.

Animals↗