Weight, carcase composition and reproductive performance of pheasants (Phasianus colchicus) fed restricted or...

Artificially reared hen pheasants, released in summer, are reported to have little reproductive success in the wild the following spring. One possible explanation is that such birds are unable to obtain an adequate diet after supplementary feeding ceases in February. When captive hen pheasants were fed an unrestricted diet they maintained constant muscle mass and fat reserves throughout the laying period. Hens restricted to pre-lay maintenance levels of nutrition after photostimulation initially laid good quality eggs at the same rate as the fully fed hens. However, by the time that they had laid the equivalent of one clutch of eggs, their energy reserves were approaching exhaustion, suggesting that they would have been incapable of incubating the eggs successfully. When fully fed hens were given wheat in place of a breeder diet, they quickly stopped laying but recovered equally quickly when fed a balanced ration again.