Abstract

Herd testing, in which individual cow’s production performance is measured, is infrequently carried out in New Zealand with at least a month between tests. A composite sample is collected from each cow and is analysed for fat, protein, and somatic cell count (SCC). The process is time consuming, and provides only a snapshot of these components. To create a more frequent, automated, on-farm system, sensors need to be developed that measure fat, protein, SCC, and other milk components inexpensively and easily. One potential measurement method which could be used in these devices is visible to near infrared (NIR) spectroscopy. The industry currently uses a range of sophisticated machines (Fossomatic, Foss, Hedehusene Denmark) for the determination of milk constituents. These machines homogenise milk and use infrared (IR) spectroscopy in the wavelength range 3500-9600 nm to determine fat, protein, and lactose concentrations. SCC is determined by an integrated flow cytometer. The NIR region (1000-2500 nm) has also been successfully used to determine constituents of milk and milk products (Rudzik & Wüst, 1998). Any inexpensive, on-line sensor based on NIR spectroscopy should function without the requirement for homogenisation and use low-cost silicon photodetectors, which are sensitive from 400-1100 nm.

DS, Whyte, R Kunnemeyer, and RW Claycomb

Proceedings of the New Zealand Society of Animal Production, Volume 60, Hamilton, 19-20, 2000