Effects of a fiber-rich diet on physiology and survival of farm-reared red-legged partridges (Alectoris rufa).

The sudden shift from a commercial energy-rich, fiber-poor diet to natural food is assumed as one of the causes of the low success of gamebird restocking. We fed farmed red-legged partridge (Alectoris rufa) chicks with a diet rich in fiber from their first month of life to the time of their release to assess the possible effects on morphometric characteristics and plasma biochemistry and whether those effects enhance survival after release into the wild. At the time of release, treated partridges showed heavier gizzards and bursas of Fabricius and longer small intestines than control birds fed commercial feed. Treated birds had also smaller pectoral muscles, lighter spleens and lower plasma levels of proteins, glucose, cholesterol and triglycerides. After release and radiotracking in a hunting area, we found no differences in the survival between both groups. Survival at the end of the study (day 39) was 58.3+/-14.2% for the control group and 24.2+/-13.8% for the treated group. The fiber-rich diet seems to have important effects on the physiology of the red-legged partridge, not always taken into account in previous studies.