Published in Scientific Papers. Series D. Animal Science, Vol. LIX
Written by Ionică NECHIFOR, Constantin PASCAL
Interest of sheep breeders of Karakul of Botoşani breed led to the pursuit of activities of technical evaluation and management of quality of pelts to a variety of colour approved in Romania in the year 2012. The entire batch of lambs subjected to assessments in each generation analysed come from crossings between genitors who belonged to the same variety of black colour. The aim was to study the mode of transmission of the characteristics that influence directly the quality of pelts when applying homogeneous crossings. Breeding activity was based on matching-pairs and was made on the basis of a number of differet couples, taking into account, however, the origin, the home line and the goal of improvement. Appraisal method of transmission of the characters which depends on the quality of pelts was realised on the first day after birth, taking account of the technical instructions and specifications of the certificate of origin and productive value. Classification of lambs in relation to the productive performance was done on the basis of final total average score. The study was conducted on successive generations of lambs obtained in the calving season between 2010 and 2015. From the analysis of the way in which descends in descent the waited characters is found that the process of improvement must be based, in particular, on an intensification of selection and on retention for breeding only the rams which show an improvement effect. Character analysis represented by the curl shape indicates that the desired types show a considerable improvement, as the last generation of assessed lambs, the valuable curl forms to be identified in over 70% of the total number of lambs subjected to research. Also, the effect of the selection applied it notes that at the apprizing of the curls after size, the desired type has rising values which confirms that the process of genetic improvement is one way. Instead, variations observed in ranking lambs in livestock classes after the total score value indicates a decrease from 33.3% to only 9% of lambs that meet the minimum requirements for the record. This suggests that it is necessary to measure the immediate reassessment of the reproductive couples and on the medium and long term a stronger selection for base characters and the application of more effective testing of males.
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