Reproduction in farmed red deer:3. Hind growth and mortality

Abstract

SUMMARY: The growth and mortality of red deer hinds from 3 months of age were analysed using data from a farmed stock. Calf mortality from 3 to 15 months of age was 11 % and was highest in the 2 months immediately after weaning. Mortality in the 8 years subsequent to the hinds reaching 15 months was low and based on 924 yearly records of survival was 1·8% per annum.The rate of growth of the calves during their first winter was markedly affected by the amount of feed given and slightly (though highly significantly) greater for the larger calves. In the subsequent summer there was no effect of weaning weight on gain. This varied considerably from year to year.The subsequent growth of the hinds showed that an equilibrium weight of about 82 kg was achieved, and that body weight at the beginning of the year, age, and whether or not the hind produced a calf, all affected the increase in body weight during a particular year.The results are combined to estimate the effects of culling the hind stock at different ages on the number of surplus female calves and the effects on lifetime reproductive performance of the body weight of hinds when 15 months of age. The latter can be predicted from weaning weight and winter feed intake provided gain from 10 to 15 months at pasture can be estimated. The partial effects of giving additional concentrated feed in the first winter were estimated and found to be appreciable.Comparisons of the results are made with mortality rates and body weights estimated by others for wild populations.