Abstract:
Animal Production in Australia Vol. 15 A CALVING SURVEY IN WESTERN VICTORIA B.W. KNEE* and D.V. NAPTHINE** A survey conducted in the North East of Victoria (Ada, pers. comm.) and information from private veterinary practitioners suggested that beef reproductive rates were low. This survey was undertaken in the Western District of Victoria to get an accurate estimate of beef cattle reproduction rates. Forty-five properties, each with between 50 and 200 breeding females, were visited on three occasions. A visit was made pre-calving to count the number of females to calve. Subsequent visits were made three weeks and 10 weeks after calving was due to begin. At each visit the number of cows and calves was accurately counted and sales and deaths recorded. Reproductive performance was calculated as a percentage of calves born per hundred cows mated. Three weeks after the due calving date, 57% of females had calved. This figure ranged from ll-88% between properties. After 10 weeks, 85% (48-97%) had calved. Cows calved first at two years of age on 77% of the properties visited. Two year old heifers averaged 57% (O-98%) of calves on the ground after three weeks. After 10 weeks, 84% (39-100%) of heifers had calved. The average ( SD) joining period for herds in this survey was 119 ( 45) days with a range of 60-249 days. Investigations were undertaken in four herds with a calving performance after three weeks below 40%. In three cases the poor performance was attributed to bull breakdown. The overall calving performance suggests beef female A 57% calving in the first three weeks suggests that joined were cycling during the first three weeks of in each of the calving figures indicates that there improvement on many properties. fertility is the majority mating. The is tremendous satisfactory. of beef females large range scope for If we set a three week calving target of 65%, there were 58% properties below this figure. Equally as important is the potential for improved levels of fertility in beef herds. Of the properties visited 25% had three week calving performance in excess of 70% and 14% had more than 75% of cows calving in the first three weeks. We believe improvement is possible in the overall three and 10 week figures by paying more attention to bull fitness and fertility. Reduction of the joining period and thus putting pressure on the fertility of late calving cows could also improve the three and 10 week performance in the longer term. Acknowledgements: We wish to acknowledge the assistance of the following Departmental officers:G. Whipp, P. Cumming, T. Glynn, C. Roycroft, A. Jack, L. Toohey and A. O'Connor. * District Office, Department of Agriculture, Hamilton, Victoria, 3300. ** Veterinary Field Services, Department of Agriculture, Hamilton, Victoria, 3300. 703