Productivity of Gansu wapiti on the Sunan deer farm

HOU Fu-jiang~1, LI Guang~2, CHANG Sheng-hua~1, YU Ying-wen~1, AN Yu-feng~3(1. Gansu Grassland Ecological Research Institute, College of Pastoral Agriculture Science and, Ministryof Agriculture, Lanzhou 730020, China; 2. Department of Computer Science, Gansu AgriculturalUniversity, Lanzhou 730070, China; 3. Yugu Minority Autonomous County Deer Farm of Sunan, Sunan 744000, China)

Sunan deer farm; Gansu wapiti; deer velvet; body dimensions; herd structure; reproduction; body weight; production system benefit

The basic situation of Gansu wapiti on the Sunan deer farm was investigated from 1999-2001. Fresh velvet production per deer showed change with age like a protruding parabola, peaking at 11 years old. This change showed 3 stages, namely, quick production increase (1-6 years), slow production increase (6-11 years), and reducing production (after 11 years). There were very significant positive correlations between fresh velvet production per head and body weight (P<(0.01)), total velvet production (P<(0.01)), and herd population (P<(0.01)). The size of Gansu wapiti in the 8 wapiti subspecies of China is comparatively small. Body length and head length indices were lower for fawns than for mature deer, but indices of limb length and neck circumference of fawns were higher. Chest circumference and body indices of male fawns were higher than those of mature stags, whereas those of female fawns were lower than mature hinds. Body dimension indices of mature deer showed greater difference between sexes than the differences for fawns. In 1999 and 2000, the average reproductive rate of appropriately aged hinds was 61.5%, and the average fawn survival rate was 55.6%. The reproductive rate of hinds gradually increased from 3 to 5 years old, then decreased after 5 years old. Accidental injury and disease were the two major factors influencing the fawn survival rate. The Sunan deer farm Gansu wapiti herd showed a pyramid form age structure. Inappropriate sale of Gansu wapiti has resulted in an imbalanced sex and age structure. The sex ratio was positively correlated to velvet value. The sex ratio change followed an approximate eight-year cycle, and could therefore be used to forecast the velvet market. Up to six years old, stag body weight showed exponential increase. One-year-old stags could reach about 60 kg body weight, and the ratio of output to input was 4.26 after selling their meat. They have development potential to become meat-producing livestock. Through optimization of the alpine grassland - Gansu wapiti production system on the Sunan deer farm, economic benefit increased 3.3 times and benefit fluctuation risk reduced 2.7 times. Based on this investigation and the development forecast of Gansu wapiti, six suggestions for research and production were given.