Compilation and analysis of existing reproductive performance data for a sample of the southern Australian beef herd

Summary

The purpose of this project was twofold  
(i) to compile a large body of data into a friendly and easily accessible format and, 
(ii) to analyse some of those data to examine effects on herd reproductive performance. 
​NSW Department of Primary Industries (DPI, formerly Agriculture) has been conducting research in beef cattle for many years, notably since the early 1960's at Trangie and early 1970's at Grafton. Over this time many experiments have been conducted by many scientists, accumulating a huge bank of data but which was stored in several different ways of greater or lesser complexity, and not easily accessible. These data needed to be collated and converted to just one easily managed system, standardising both the system itself as well as the type and format of the information stored. This would then allow retrospective interrogation of historical data across the complete range of past experiments, as well as providing a standardised system for the future. 
The data made accessible by this compilation exercise, provided the means to extract sub-sets that could be analysed to describe levels of fertility and to test for specific genetic and non-genetic effects. The results were expected to provide information for use in extension programs addressing beef production needs and to indicate possible issues for future research. 
Achievements 
The primary aim of this project was achieved in assembling data from NSW DPI beef cattle research projects into databases with standardised format. The Informix SQL relational database system was chosen as the most appropriate as it is considered efficient and friendly, and was already being used to store some of the cattle research records. The data captured, which is continually updated with data from ongoing research, relates not only to reproductive performance, but also many other production and carcass traits associated with the animals involved in the experiments. 
Recommendations 
This database should be further interrogated to examine relationships not able to be addressed within this project, since the analyses that were completed have shown that the data set has much more to yield if funding and staff resources are available. For example, the issue of repeatability of calving performance, as indicated by the effect of previous calving in the analyses, could be further examined with larger data sets than possible in this study using current and future data. Data from the NFI line at Trangie also warrants further examination as the effects on reproduction for such selection is very important to industry. The effect of calving spread caused by variation in proportions of cows conceiving in the first 2 cycles should be highlighted in extension programs that deal with cow/calf production and profitability. The management of the cow herd to optimise liveweight and body condition throughout the breeding cycle must however remain the key issue of importance to breeding strategies. This provides the means to maximise both early and total pregnancy rates.