Genetic Improvement of Functional Traits in Cattle Report from EU Concerted Action GIFT

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1 1 Genetic Improvement of Functional Traits in Cattle Report from EU Concerted Action GIFT A.F. Groen Animal Breeding and Genetics Group, Wageningen Institute of Animal Sciences Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands For information on the EU Concerted Action GIFT please contact: Hans Aumann ) Vincent Ducrocq (Jouy-en-Josas, ) Nicolas Gengler (Gembloux, ), Ab Groen (overall co-ordinator, Wageningen, ) Hans Sölkner (Vienna, ) Erling Strandberg (Uppsala, ) or look at Internet home page: 1. Introduction The recognition of the importance of functional traits (like health, fertility, metabolic stress and longevity), and the possible role of animal breeding in avoiding deterioration and possibly improving functional traits has led to many research activities. Research focuses on tool development (un-ambiguous trait definition, reliable trait recording and proper evaluation procedures) and tool implementation (optimisation of breeding programmes balancing selection for functional traits and production traits). The state of the art in these areas was reviewed at a workshop in Gembloux (INTERBULL bulletin no. 12, 1996). At this workshop it was decided to apply for EU subsidies to organise an international concerted action on genetic improvement of functional traits in cattle. EU subsidies were granted and the 3-year GIFT concerted action was started January Objectives of this GIFT concerted action are: To bring together researchers and people from breeding organisations to develop concepts for genetic improvement of functional traits by defining breeding goals and breeding strategies; To enhance collaborative efforts for the further development of efficient recording systems and breeding value prediction procedures; To stimulate the exchange of existing knowledge about the genetic evaluation of functional traits; To develop recommendations for breeding programmes for functional traits. Activities of the GIFT concerted action should contribute to sustainable development of cattle production systems, improving animal welfare, improving consumers acceptance of products and production systems ( healthy food from healthy animals ) and facilitating international trade of genetic material. This report summarises activities and deliverables of the GIFT concerted action. The report also presents a general approach for considering functional traits in cattle breeding strategies, and an outline on planned future activities.

2 2 2. Activities GIFT concerted action Three main activities are organised to accomplish the objectives of the GIFT concerted action: visits, Internet site and workshops. The GIFT project financially supports visits of personnel from participating institutes for the development and exchange of computer programs, the inspection of recording systems, and the enhancement of collaborations in research projects. The GIFT home page [ reports on activities and announces future activities. From the home page, standard computer programs for the routine evaluation of functional traits are made available (i.e., for multi-trait evaluations with missing data and for analysis of categorical traits). A series of four GIFT workshops was organised focussing on four main groups of functional traits: 1. Health Uppsala, June 1997, focussing on possibilities for direct and indirect selection for improved udder health and reduced feet and legs problems (proceedings INTERBULL bulletin no. 15) 2. Fertility and Reproduction Grub, November 1997, with special attention for female fertility, calving ease and still birth (proceedings INTERBULL bulletin no. 18) 3. Metabolic Stress Edinburgh, October 1998, developing an interdisciplinary view on selection for feed intake capacity, body weight and condition score (proceedings joined publication BSAS/BCVA/GIFT/INTERBULL) 4. Longevity Jouy-en-Josas, May 1999, summarising both the state of the art in and challenges for the evaluation of longevity, with special reference to the use of survival analysis (proceedings INTERBULL bulletin no. 21) Presentations and discussions during the initial workshops have stimulated a further development of accurate genetic evaluations for functional traits. Research areas for further research on the biological and genetic backgrounds of functional traits were identified. Recommendations were put forward for improving and standardising national and international recording and evaluation of functional traits. Recommendations from the first two initial workshops were approved at the intermediate report workshop in Warsaw, August 23 rd, 1998 (see also GIFT Annual Report, INTERBULL bulletin no 19). At the intermediate report workshop in Warsaw, a seminar Developments in dairy cattle breeding with special reference to functional traits was held. The papers give a comprehensive overview of current developments in dairy cattle breeding, from an industry point of view, from the point of view of meeting future consumer demands, and from the scientific point of view on methodology (becoming) available (see INTERBULL bulletin no. 19). The GIFT concerted action has established co-operation with the EAAP and ICAR for the organisation of workshops and the dissemination of deliverables. Partnership of INTERBULL facilitates a world-wide distribution of the proceedings. Inclusion of partners from both research and breeding organisations gives a short time lag from development to implementation of breeding value estimation programs. From participants to the activities and other people interested in the deliverables, a major signal regarding future challenges is that GIFT should try to enhance more directly future joint research efforts, for example by joint application of funding. It also becomes evident that there is a strong demand for more explicitly defining and forwarding the recommendations and proposed procedures for genetic evaluations for all functional traits. Still too many countries do not properly process the recorded information on functional traits (or indicator traits) or do not record information at all. Forthcoming activity is the final report workshop in Wageningen, November 7-9, This workshop will focus on breeding goal definition and breeding schemes combining

3 3 selection for functional and production traits. There will be four main sessions on: breeding goal definition: the choice of traits and the derivation of economic values how to combine functional traits and production traits (health, fertility, metabolic stress, longevity) in a breeding goal; selection schemes: different approaches for the selection on functional traits (total merit index, 2-step selection, mating strategies); from recording to predicted breeding values (recording schemes, data logistics, index presentation for functional traits); the role of conformation in the selection for functional traits. At the end of the workshop, business meetings will be held to co-ordinate and prepare joint research activities to be submitted for financing (for example with the EU as shared costs projects). Initiatives for business meetings have been taken for four different subjects: using survival analysis to reveal information on specific reasons for involuntary culling, routine use of body condition scoring in selection for efficiency, health and fertility in dairy cattle, selection for calving ease in dairy, dual purpose and beef breeds, and adaptive fitness. Functional of or serving a function; designed or intended to be practical rather than necessarily attractive or pleasing; affecting the function of a bodily organ but not its structure [The Oxford Dictionary]. In the present situation exchanges of genetic material are carried out based on yield and conformation traits. A reasonable and sound long term objective is that conformation traits would be replaced by functional traits and used only as predictors. The consumer would better understand that cattle is being selected on health traits, not on fancy traits. Finally, business could be as alive as ever but on a more sound basis. [ Report EAAP working group; Groen et al., 1997 ] 3. Selection for functional traits A genetic improvement strategy is an integral part of farm management. More specific, genetic improvement is part of tactical and strategic planning of animal production. A general representation of the cyclic process of farm management is given in Figure 1. In the area of genetic improvement, the management cycle starts with the definition of the breeding goal and the mating plan. The breeding goal and the mating plan are the framework in which the actual selection and mating of males and females are to be implemented. However, the implementation of selection and mating is only possible with adequate information on the predicted breeding values of potential selection candidates. The required predicted breeding values are to be derived by appropriate processing of adequately recorded data. Data recording and processing is a joint effort involving individual farmers, herdbooks, AIservices, veterinarians, organisations that test and market bulls, governmental organisations, and others involved in dairy cattle production. It is essential that the information for the decision-making is coherent with the breeding goal and mating plan. It is a joined responsibility of all organisations involved that potential selection candidates have predicted breeding values for a broad range of traits. Taking a consumer-oriented market approach, breeding organisations should provide information on all main groups of traits that farmers include in their breeding and mating decisions. As dairy cattle breeding is an international business, this responsibility should be picked up

4 4 internationally, providing prediction breeding values that can be made comparable over borders of nations and between different breeding organisations. Planning Implementation Control animal identification, milk records, conformation scores, health records, AI-data, RECORDING DATA [internal and external] PROCESSING INFORMATION breeding selection and goal and mating of males predicted breeding values for mating plan and females; breeding goal traits on potential selection candidates Operational cycle Tactical cycle Strategic cycle Genetic improvement Figure 1. A general representation of management on farm level, exemplified by decision making in genetic improvement. Although research has been undertaken for a long period, providing information on functional traits (i.e. predicted breeding values on potential selection candidates) is still a major effort for animal breeders (Groen et al., 1997). There is a broad interest in this information from farmers as their breeding goals include functional traits. Functional traits have an economic value in the breeding goal, because of the direct impact of the (genetic) level of these traits on farm profit and product prices. Moreover, functional traits also have non-economic values (Olesen et al., 1999) because of their direct impact on animal welfare and consumer acceptance of the products. Breeding organisations should be able to monitor the genetic trend of functional traits as part of their own management, and the dairy sector as a whole should be able to respond on questions from governmental and nongovernmental organisations (e.g., pressure groups). Data recording and processing is costly, certainly when reliability is sought for. There is a price to be paid for the information provided with potential selection candidates, and consideration is to be given to costs and benefits from each part of the information provided. Starting point, however, should be a consumer- (farmer-)oriented service each serious question by a significant group of farmers should be respected and considered seriously, thus allowing a customised farm or farmer-specific selection. Of course the total list of predicted breeding values provided per selection candidate should be both complete and comprehensive, and preference should be given to breeding values that are mutually exclusive. Based on this, Table 1 proposes a list of functional traits for which predicted breeding values for potential selection candidates should be made available. Different groups of farmers are interested in different (levels of) details on predicted breeding values each farmer should be able to assess the

5 5 details of interest. For official sire summaries and overall bull ranking, presentation of combined indices per functional trait group, and definition of (national or international) overall indexes should be considered. For customised selection and mating decisions (per farm or group of farms) programs (e.g., computer-based) should be developed. This procedure allows flexibility in terms of individual or group based (regional or national) preferences for selection (i.e., breeding goal definition), and also facilitates international comparison (and use) of genetic material. It also allows differential use of predicted breeding values in terms of selection and mating strategies, e.g. truncation selection on indexes for individual traits or combined indexes, or considering a trait in (assortative or compensatory) mating after selection on other traits. Table 1. A list of functional traits for which predicted breeding values for potential selection candidates should be made available (After Groen et al., 1997) Functional trait group Predictor traits 1 Other related traits 2 Calving ease (CE) Direct CE Indirect or maternal CE Rump angle Rump width Udder health Clinical and subclinical 3 Udder conformation (esp. udder depth, fore udder attachment, front teat placement or length) Somatic Cell Score Milking speed Birth weight Gestation length Still birth Feet & legs problems Clinical and subclinical 3 Mobility scoring Claw diagonal Rear legs set (side or hind view) Fertility Workability Feed efficiency Regular showing heat Becoming pregnant Milkability (flow pattern or milking speed) Character Body weight Feed intake capacity Functional longevity Length of productive live corrected for (within-herd) milk production level Days open Non-return rates Body measurements or scores (esp. hip height, body depth, rump width, hearth girth) Other functional traits Hormone levels in milk Dynamics in body condition and body weight, persistency of milk production 1 These traits could be used, possibly in addition to data on the functional traits, in the (indirect or combined) prediction of breeding values of the functional trait. 2 These traits could also be used for combined prediction or predicted breeding values on these traits could serve as alternative information source for selection on the functional trait. 3 Farmers, veterinarians and claw trimmers could perform data recording.

6 6 4. Future activities The core-group of the GIFT EU Concerted Action considers it to be a challenge to have participating institutes work together on research proposals for (external) funding of research on functional traits, both fundamental (e.g., on physiological backgrounds) and applied (e.g., practical recording, evaluation and selection programmes). The final report workshop in Wageningen will facilitate business meetings for joint research project development. A second challenge is to try to continue the co-operation among the participating institutes and expand with other institutes. ICAR has taken the initiative for a Working Group on Functional traits. During the GIFT workshops recommendations on trait definitions and trait evaluations were defined. These recommendations should be further formalised, giving: 1. a basic list of traits (an international standard package) - which predicted breeding values should be made available on selection candidates, with a clear distinction between breeding goal traits and predictor traits. 2. per breeding goal trait, appropriate procedures for breeding value prediction (within and across countries). Recommendations will be formalised in official documents. These documents will include aspects like availability of standard computer programs for routine evaluations, alternative procedures for evaluations (in case of missing recordings on specific traits), and publication of predicted breeding values. The ICAR Working Group on Functional Traits has also been asked to develop standard methods and coding for health and fertility recording, and to consider the ways in which the recording can link in with the requirements of disease eradication programs and with product quality assurance scheme record requirements. References Groen, A.F., Steine, T., Colleau, J.J., Pedersen, J., Pribyl, J. & Reinsch, N Economic values in dairy cattle breeding, with special reference to functional traits. Report of an EAAP-working group. Livest. Prod. Sci. 49, Olesen, I., Groen, A.F. & Gjerde, B Definition of animal breeding goals for sustainable production systems. J. Anim. Sci: accepted.