Estudio de la supervivencia de los gazapos desde el nacimiento hasta el destete en varias líneas de selección en conejos

Abstract

[ES] El tamaño de camada es el principal carácter en importancia económica en conejo y por ello es objeto de selección en los programas comerciales; sin embargo, debido a su baja heredabilidad, la selección por tamaño de camada supone un desafío en especies prolíficas y el progreso que se ha realizado ha sido muy lento. El objetivo desl trabajo es establecer el periodo de mayor mortalidad para proponer un nuevo criterio de selección que permita mejorar mejorar el tamaño de camada de forma más eficaz. Para llevar a cabo el objetivo se va a medir diariamente el número de gazapos vivos y muertos desde el nacimiento hasta eel destete en varías líneas de selección que se encuentrran en las granjas de mejora de la UPV. Además se van a a estudiar las principales causas de mortalidad.

[EN] The litter's size is one of the characteristics with greater economic weight in rabbit production . The objective of this work is to study the extent and distribution of mortality from birth to rabbit weaning to propose a new selection criterion to improve litter size . 316 birth data of seven lines of rabbit were taken from UPV's rabbit genetical breeding farms. The size of the litter , the day the rabbits died and possible cause of death was recorded from birth until weaning, that was conducted on 28 post -partum. It was also observed during the first 5 days if the rabbit breastfed or not. In analyzing the data it was obtained that 51.6 % of the mortality occurred in the first week and that most of the mortality until weaning had already occurred at the end of the second week of life with 87.4 %. No significant differences were observed between the lines , it would require more data of each line to determine if there are differences in the distribution of mortality from birth to weaning . The major causes of death are death from birth (25 %) , starvation (25 %) and diarrhea (21%). Starvation is the leading cause of mortality in the first week of life, while diarrhea are in the second week. In view of the results it was decided to propose as a new criterion for selecting the number of live rabbits 8 days post-partum mortality since the second week occurs from diarrhea that can be solved with good management. Before starting a program selection criterion should collect more data and estimate the heritability and the expected response to this new selection criteria.