
%0 Journal Article
%A Armstrong, D. P. 
%A Knee, J. E. 
%A Doyle, P. T. 
%A Pritchard, K. E. 
%A Gyles, O. A. 
%T Water-use efficiency on irrigated dairy farms in northern Victoria and southern New South Wales
%J Australian Journal of Experimental Agriculture
%D 2000/08/30
%V 40
%N 5
%P 643-653
%K 
%R https://doi.org/10.1071/EA99132
%U https://www.publish.csiro.au/paper/EA99132 
%X A survey of 170 randomly selected, irrigated, dairy farms in northern Victoria and 9 in southern New South Wales was conducted to examine and benchmark the key factors influencing water-use efficiency. Water-use efficiency was defined as the amount of milk (kg milk fat plus protein) produced from pasture per megalitre of water (irrigation plus effective rainfall). Information on water-use, milk production, supplementary feeding, farm size and type, pasture management, and irrigation layout and management was collected for each farm by personal interview for the 1994&#8211;95 and 1995&#8211;96 seasons. The farms were ranked in the order of water-use efficiency with the average farm compared with the highest and lowest 10% of farms. The range in water-use efficiency was 25&#8211;115 kg milk fat plus protein/ML, with the highest 10% averaging 94 kg/ML and the lowest 10% averaging 35 kg/ML. The large range in water-use efficiency indicated potential for substantial improvement on many farms. The high water-use efficiency farms, when compared with the low group: (i) produced a similar amount of milk from less water (387 v. 572 ML) (P&#60;0.05), less land (48 v. 83 ha) (P&#60; 0.05) and a similar number of cows (152 v. 143 cows); (ii) had higher estimated pasture consumption per hectare (11.5 v. 5.5 t DM/ha) (P&#60;0.01) and per megalitre (1.0 v. 0.5 t DM/ML) (P&#60;0.01); (iii) had higher stocking rates (3.2 v. 1.8 cows/ha) (P&#60;0.01); (iv) used higher rates of nitrogen fertiliser (59 v. 18 kg N/ha.year) (P&#60;0.05) and tended to use more phosphorus fertiliser (64 v. 34 kg P/ha.year) (P&#60;0.10); (v) used similar levels of supplementary feed (872 v. 729 kg concentrates/cow); (vi) had higher milk production per cow (396 v. 277 kg fat plus protein) (P&#60;0.05); and (vii) directed a higher proportion of the estimated energy consumed by cows into milk production (53 v. 46%) (P&#60;0.05). The survey data confirmed that irrigated dairy farm systems are complex and variable. For example, the amount of feed brought in from outside the milking area varied from 0 to 74% of the estimated total energy used by a milking herd. There was a large range in the level of supplement input amongst the farms in the high water-use efficiency group, and in the low water-use efficiency group. This indicates that the management of the farming system has a greater impact on the efficiency of water-use on irrigated dairy farms, than the type of system. The data from the survey provide information for individual farms, a measure of the water-use efficiency of the industry, and an indication of the quality of regional land and water resources. 
