Reproductive performance of farmed red deer (Cervus elaphus) in New Zealand IV. Biological markers as risk factors for yearling and adult hind conception

A 2-year observational study of 15 red deer (Cervus elephus) farms was carr ied out in New Zealand from March 1992. In each year of study, approximatel y 1650 hinds were individually monitored for reproductive success. During f arm visits in March 1992 and 1993, five yearling and five adult hinds per f arm were randomly selected and blood sampled to define their haematological , biochemical and blood mineral profile. Faecal samples were taken for para site egg and larvae count. Biological markers potentially affecting the pro bability of conception before May 1 or of conception that year were investi gated separately using multivariable logistic regression analysis. Adult hi nds with low serum phosphorus concentrations were more likely to conceive b efore May 1. Lower conception rates were observed in yearling hinds when bl ood glutathione peroxidase, serum vitamin B12, and serum albumin concentrat ions were low, and when faecal lungworm larval counts were high. While thes e associations have yet to be proven as causal, data suggests that monitori ng and maintaining adequate blood elements, and controlling internal parasi tes in yearling hinds, may assist farmers to achieve optimum reproductive p erformance in farmed red deer herds. (C) 1999 Elsevier Science B.V. All rig hts reserved.