Animal Breeding Methods Research Articles

ECONOMIC ASYMMETRIES OF PRODUCTION IN THE AGRICULTURAL SECTOR

The development of efficient and sustainable agriculture requires its permanent transformation. In this aspect, various methods of growing plants and breeding animals are applied to optimize production. These methods are distinguished mainly as: traditional (conventional) production, organic production, production of genetically modified organisms. From this standpoint, attention is drawn to: covering the widest possible range of terms used to characterize the variety of plant growing and animal breeding methods; a brief overview of the established in theory and practice modern methods of plant growing and animal breeding; delimiting the notion of biological – as a vital process, regardless of the plants and animals production technology (including the use of organic fertilizers; preparations containing live bacteria; treated seeds with live bacteria, etc.).The methods of the present study are scientific research methods: induction and deduction method, retrospective analysis and others; illustrative methods - schemes, figures and others. Regarding the expected results, this article focuses on highlighting the social, economic and environmental aspects of production of plant and animal products. Production in the agricultural sector must be aimed at recovery of residues and waste from crop and livestock production in harmony with the environment.

Methods and applications of animal genomic mating

Genomic selection (GS) is a powerful tool which can be used to estimate the breeding value of individual animals by using the molecular markers of the animal's entire genome. GS improves the accuracy and intensity of selection, reduces the interval of generation, and realizes the effects of early accuracy selection contributing to a significant evolution in animal breeding. In the past decade, GS was successfully applied in the genetic improvement of dairy animals with improved selection accuracy and genetic gain of breeding animals. However, GS focuses on the genetic gain of target traits while it ignores the genetic relationship between mating pairs such that it ignores long term genetic merits such as an increase in inbreeding coefficient of offspring population, a decrease of genetic diversity and the homozygous presentation of harmful genes. In 2016, genomic mating (GM) was proposed as a sustainable genetic selection method using genomic information of the breeding candidate individuals to optimize selection and mating with resultant control of the growth rate of population inbreeding coefficient and achieving long-term and sustainable genetic progress. Therefore, GM is more suitable for modern animal breeding than GS, especially for the genetic improvement of indigenous species. In this review, we summarize the basic concepts, methods, and applications of GM, and then present examples comparing the effects of six simulated mating schemes. This review serves as a valuable reference for the applications of animal breeding methods.

Preventing Brucellosis in the Bedouin Society in Israel

Background: Brucellosis is endemic in the Bedouin population of southern Israel, where Poor hygiene and traditional practices including home dairy preparations, animal breeding methods contribute to disease spread. The raising of livestock has great importance in Bedouin culture. Commonly, herds of sheep, goats and camels are maintained in close proximity to living accommodations, resulting in a higher exposure to the disease. The Objectives of this study is to prevent Brucellosis in the Bedouin Society, by locating the source of infection and providing health education and promotion activates to families and Society. Methods: In Israel, Brucellosis is mandatorily notifiable since 1951. New cases are reported to the District Health Office (DHO) of the Ministry of Health and subsequently incidence rates or summarized. Epidemiological investigations that attempt to locate the source of infection preform control measures as a prevention program with health promotion and termination of infected herds if required with concurrent fair compensation of farmers. Results and Actions: The incidence of the disease is on the rise within this population. In 2003 the incidence was 18 per 100,000, yet in 2013 the incidence rate increased almost sevenfold. To control the problem, the Southern DHO established a prevention program. Veterinary services and Bedouin community leaders partnered with public health officials in order to improve herd’s vaccination rates, and to locate and eliminate infected stock. Despite these steps, the incidence continues to rise, reaching 154/100,000 in 2014. Conclusions: In order to eradicate brucellosis among the Negev Bedouins, health promotion steps are necessary, but not sufficient and a comprehensive Health Education intervention must be integrated as part of overall policy, including the proper examination of livestock, termination of infected herds, compensation of farmers and advanced culturally and socially sensitive media interventions.

The Current and Future Use of Ridge Regression for Prediction in Quantitative Genetics.

In recent years, there has been a considerable amount of research on the use of regularization methods for inference and prediction in quantitative genetics. Such research mostly focuses on selection of markers and shrinkage of their effects. In this review paper, the use of ridge regression for prediction in quantitative genetics using single-nucleotide polymorphism data is discussed. In particular, we consider (i) the theoretical foundations of ridge regression, (ii) its link to commonly used methods in animal breeding, (iii) the computational feasibility, and (iv) the scope for constructing prediction models with nonlinear effects (e.g., dominance and epistasis). Based on a simulation study we gauge the current and future potential of ridge regression for prediction of human traits using genome-wide SNP data. We conclude that, for outcomes with a relatively simple genetic architecture, given current sample sizes in most cohorts (i.e., N < 10,000) the predictive accuracy of ridge regression is slightly higher than the classical genome-wide association study approach of repeated simple regression (i.e., one regression per SNP). However, both capture only a small proportion of the heritability. Nevertheless, we find evidence that for large-scale initiatives, such as biobanks, sample sizes can be achieved where ridge regression compared to the classical approach improves predictive accuracy substantially.

Brucellosis in the Bedouin Society- health promotion and outbreak control

Brucellosis is an infectious bacteria disease contracted from animals. Poor hygiene, animal breeding methods and traditional food preparations are the main contributory factors to the proliferation among the Southern Israel Negev Bedouin. The raising of livestock still has great importance in Bedouin life; many maintain flocks of sheep goats and camels by their homes resulting in a higher exposure to Brucellosis. Infectious Disease Notifications of Brucellosis new cases are required, by law, …

Statistical methods in animal breeding and Bach’s harpsichord concertos

Fil: Cantet, Rodolfo Juan Carlos. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina. Universidad de Buenos Aires; Argentina

Bayesian structural equation models for inferring relationships between phenotypes: a review of methodology, identifiability, and applications

Structural equation models provide a general statistical modelling technique for estimating and testing relationships among variables. Such relationships are often not revealed by standard linear models, but are of importance for understanding mechanisms underlying e.g., production-related diseases, such as mastitis. This paper gives a review of Bayesian structural equation models concerning methodology and identifiability, focused on animal breeding and genetics modelling. Applications of this type of methods in animal breeding are also reviewed critically, with discussion on advantages and disadvantages of these approaches.

Genetic selection of boars

Selection of boars by visual appraisal is the simplest and oldest method used by the swine industry. However, individual performance testing, and later use of computers to incorporate relatives’ data and account for environmental variation, resulted in greater rate of improvement for economically important traits. Examples of molecular genetic tools that have increased improvement for some traits are also discussed. Accurate identification of genetic merit is increasingly important with widespread use of AI and resultant greater progeny number per sire. Historically, selection was to produce desirable progeny; however, with the majority of boars now housed in dedicated boar facilities, and the efficiency of sperm production being recorded, boar stud personnel are increasingly interested in selection of boars for fertility traits. Selecting boars that are lean and heavily muscled and have good semen parameters may be problematic, given the genetic relationships among the traits. Whereas conventional animal breeding methods will remain important, use of molecular tools will increase, and identification of a boar's fertility potential at birth will allow earlier and more efficient selection of high-fertility boars. Ability to achieve acceptable female reproduction with frozen semen would facilitate selection for longevity. However, this would lengthen the generation interval and could dilute selection intensity for other traits, as it requires indirect selection for semen freezability.

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.

Bayesian Methods in Animal Breeding with Different Prior Specification Using Gibbs Sampling

An application of Gibbs sampling in animal breeding is carried out using two different types of prior specification. The first specification has full conjugacy and the second one has non-conjugacy, which causes computational difficulties. This paper demonstrates how the Gibbs sampling procedure, making use of an adaptive rejection sampling algorithm, deals with non-conjugacy in animal breeding using a balanced one-way classification with a random sire effects model and compares the results of two different specifications. It is also shown how Bayesian methods solve the problem of obtaining a negative estimated variance.

The future role of molecular genetics in the control of meat production and meat quality

Current applications of quantitative genetics for genetic improvement of farm animals rely on sophisticated statistical procedures applied to failly simple genetic models and have been effective in producing large cumulative genetic changes in many traits. Recent advances in molecular genetics provide a potential for renewed methods in animal breeding. The two main possible fields of application of recombinant DNA methologies, i.e. marker-assisted breeding and gene transfer, are reviewed. Use of genetic markers as an aid to present breeding practice appears to be rather promising, but research effort remains to be done before implementation of marker-assisted breeding schemes on a significant scale. It is not, at this stage, obvious that transgenesis will be an important way of improving meat-producing animals, at least in the near future.

IMPUTING CHARACTERISTIC VALUES OF AGRICULTURAL "SEED-STOCK"

Statistical methods of regression and mathematical (linear) programming are employed to combine principles of economics and genetics in a conceptual, multi-step, model of valuation for biotechnical change. The resulting model has the capacity to estimate the value of changes in specific characteristics for specific production environments, whether those changes are accomplished by traditional plant and animal breeding methods or by genetic engineering. The application of the model is illustrated with an example of commercial cow-calf production under conditions typical of the Texas Panhandle using a total of 32 breed groups.

Teaching Methods in Animal Breeding: Teaching with Self-Instructional Modules

The number of students enrolling annually in courses in dairy science at Michigan State University has tripled in the past 10 yr, and doubled in 5 yr while there has been no increase in number of faculty. Students times credit hours have now reached approximately 6,000 per year (1). Enrollment in Introduct ion to Dairy Production (DRY 214) has increased from 246 students in 1 9 6 8 6 9 to 503 students in 1976-77 . In addit ion to being more numerous, students are more heterogeneous in both experiential and academic backgrounds. Many of these students have not lived on a farm, and some never had observed a cow closely. During 1976--77, 44 different majors were represented in the course. The range of classes included 2% graduate, 14% seniors, 18% juniors, 40% sophomores, and 26% freshmen. Complicating the task of instruction in DRY 214 is the range of subjects and the consequent burden on a single lecturer. This course introduces various areas in dairy production and advanced courses offered by the Dairy Science Department. Dairy majors and students in preveterinary medicine are required to complete DRY 214. To increase instructional efficiency and to enhance learning, the dairy science faculty under took an instructional improvement project. The project has been supported by the college, university, and industry (1). Part of the project is development of a learning center within the department to provide a site for auto-tutorial instruction with units of Structured Learning and Training Environment (SLATE) and a site for laboratorial activities and demonstrat ions in a flexible multi-use facility. A teaching specialist was hired by the department to manage the learning center and

The utilization and conservation of the world's animal genetic resources

The utilization and conservation of animal genetic resources constitute a complex set of problems. Simultaneous consideration must be given to the immediate need for genetic improvement, and to the conservation for future unforeseen needs — as well as for historic and scientific purposes. Because of rapid adoption of intensive selection methods in animal breeding and the introduction of artificial insemination, the genetic composition of the livestock populations of the industrialized countries is currently undergoing very rapid changes. In the Third World, livestock are largely bred and managed in traditional systems, although modern techniques are likely to be introduced at an increasing rate in the decades to come. An account is given of the rapid changes in the cattle breed composition in Europe and the Mediterranean basin. Of the total number of breeds which existed in 1970, 115 indigenous breeds are threatened by extinction and only 30 are holding their own. There has been a change towards Friesian cattle in the lowland areas and towards Simmental cattle in the moderately elevated areas of central and south-eastern Europe. Reasons are discussed why we need to conserve animal genetic resources, e.g. the cultural, historic and scientific interests on the one hand, and the more practical/economic ones on the other. Examples are given of breeds which, for historic reasons, should be conserved. However, to meet practical/economic needs in the future, ought to be the most important reason for conservation, and yet that type of conservation is often most difficult to justify and to arrange in practice. That changes in general economic conditions may completely reverse an earlier decline in numerical strength of animal strains is exemplified by the current use of Cornish chicken in many broiler strains, the present interest in former draught cattle of southern Europe to produce lean carcasses of beef and the use of the Finnish Landrace sheep to boost lambing rates through crossbreeding. Methods for assessing the decay of genetic variation are briefly discussed. Blood groups and other biochemical polymorphisms may be usefully employed as “marker genes” to measure the overall change in genetic variation; examples of such studies of north-west European cattle breeds are reviewed. Many different possibilities of conserving animal genetic material exist. Animal parks are gaining popularity and should be utilized more in the future. In species as cattle, where semen can be kept frozen and used for artificial insemination, storing frozen semen is a relatively cheap way of medium-term conservation. Work is now underway on several species for the storage of frozen embryos. The developing countries require special attention with regard to the utilization and conservation of animal genetic resources. The genetic variation of the animal populations in the developing countries appears to be very large. Local strains are often well adapted to stresses in the environment such as high solar radiation, periodic droughts and various diseases. Large-scale programmes for the evaluation of the animal strains are required. The occurence of cattle strains in West Africa, e.g. Baoulé and N'Dama, which show a high degree of tolerance towards trypanosomiasis is interesting. Their use in heavily tsetse-infested areas as an alternative to bush clearing and spraying with insecticides needs further investigation and/or promotion.

The effects of selective breeding on the laboratory propagation of insect parasites

The formal application of certain animal breeding methods has been investigated in the laboratory propagation of a chalcid parasite, Microplectron fuscipennis Zett. An account is given of the methods used with reference to their value in the propagation of other insect parasites. Through selective breeding, laboratory production permitted the distribution of 889 million parasites over the spruce sawfly infested area in Canada. Selection in the breeding lines brought about a continuous decrease in the number of sterile males from 35 to 2%; an increase in the mean number of offspring per mother from 34 to 68 and an almost equal reduction in variability of development, oviposition and length of adult life. Tests are reported on the effects of inbreeding and outbreeding on these lines using wild and laboratory-reared stock.

New Methods in Animal Breeding: The Importance of Ultra Violet Light in Animal Breeding.

New Methods in Animal Breeding: The Importance of Ultra Violet Light in Animal Breeding.