Reproductive performance of farmed red deer (Cervus elaphus) in New Zealand - I. Descriptive data

A longitudinal observational study of 15 red deer (Cervus elaphus) farms wa s carried out in New Zealand for 2 years from Mar 1992. Management of hind mobs and their composition during mating, calving, and weaning were recorde d. About 2700 hinds were individually monitored for live weight, body condi tion score and reproductive success. All hinds were pregnancy tested in Jun e by ultrasound and classified as having conceived before May 1, after May 1, or as being not pregnant. Calving dates and dam-offspring pairs were rec orded on four farms. The lactational status of hinds and live weight of cal ves were recorded at weaning. Mean pre-mating live weights of yearling hind s were 81.3-82.8 kg and of adult hinds 98.0-98.7 kg, respectively, for each year of study. The percentage of yearling and adult hinds conceiving befor e May ranged from 8.3 to 95.0% and from 77.6 to 98.4%, respectively, betwee n farms. Overall, the proportion of yearling and adult hinds not pregnant w as 15.3% and 3.2%, respectively. Pregnancy rates at scanning of adult hinds within mating mobs were generally over 90%, and 41.7% of mating mobs had 1 00% pregnancy rates. In contrast, the pregnancy rates of yearling hind mobs were more variable, with five mobs below 50%, and 34.1% of mating mobs ach ieving 100% pregnancy rate. Estimated in utero loss rates from pregnancy di agnosis to calving were 0.66 and 0.79% for yearling and adult hinds, respec tively. From four farms, median calving dates of yearling and adult hinds w ere Dec 13 and Nov 30, respectively. Overall, calf survival rates to weanin g of yearling and adult offspring were 84.1 and 91.6%, respectively, while the reproductive efficiencies (number of calves weaned per hind mated) were 70 and 83.6%, respectively. Farm mean weaner Live weights standardised on Apr 1 ranged from 42-59 kg and 39-51 kg for stags and hinds, respectively. These data are currently the best estimates of reproductive parameters of N ew Zealand red deer herds, and highlight a wide variability in reproductive indices between farms. (C) 1999 Elsevier Science B.V. All rights reserved.