@conference {41513,
	title = {Remote automatic selection of cows for milking in a pasture-based automatic milking system},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {64},
	year = {2004},
	month = {Jan},
	pages = {241-245},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {New Zealand pastoral dairy farming presents unique challenges for combining automatic milking systems (AMS), including long walking distances, large herds, year round pasturing and a predominately fresh pasture diet. This paper describes a system designed to minimise walking, maximise the efficiency of AMS utilisation and enable control of individual cow milking frequency by remotely selecting cows for milking up to 400 m from the dairy. Cows report to a selection unit (SU) located in the centre of a block of pasture and linked via raceways to the AMS. Entry is via one-way gates and exit via a computer controlled drafting gate, which directs the cow either to the dairy or the paddock depending on time since last milking. A communication cable connects the SU to the AMS server in the dairy. Cows wear an electronic identification device. Water and pasture access act as incentives for cows to enter the SU. Cows readily learned to use the SU and were observed visiting the unit at every hour over 24 hours. Twenty-seven cows were assigned to either a 6h or 12h minimum milking interval (MMI). On average, cows visited the SU 4.5 and 5.5 times/d for the 6h MMI and 12h MMI groups, respectively, and achieved a milking frequency of 1.9 and 1.4 milkings/d, respectively. Results showed that milking frequency can be controlled via a system for remotely selecting cows for milking and that access to fresh pasture is a strong factor in motivating cow traffic through the SU. },
	issn = {1176-5283},
	author = {Jago J and Bright K and Copeman P and Davis K and Jackson A and Ohnstad I and Wieliczko R and Woolford M}
}
@conference {41328,
	title = {An innovative farm system combining automated milking with grazing},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {62},
	year = {2002},
	month = {Jan},
	pages = {115-119},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {The harvesting of raw milk for the New Zealand dairy industry is a labour intensive process. Technology to completely automate the milk-harvesting process has been developed in Europe and is operating on an increasing number of commercial farms in several countries. A research programme has been established at Dexcel to develop innovative pasture-based farm systems utilising existing automated milking technology. A new farm layout was designed and implemented on a 10 ha farmlet. The land was radially subdivided into eight paddocks leading to a central collection area. A 200-m two-way race extended between the collection area and a small waiting yard adjoining a Fullwood Merlin automated milking system (AMS). Water was only available in the central collection area, the holding yard and as cows exited the AMS. Cows had access to the AMS for 24h/day where they received a maximum of 2kg concentrate/ 24h. A herd of 41 mixed-age cows was milked in the farm system. Data for a 14-day period in October when cows had settled into the system were analysed. Cows voluntarily visited the AMS 2.7 times/24h and were milked 2.3 times/24h. Visits were distributed over 24h with the lowest number of visits occurring between 0330 and 0600. Cows demonstrated remarkable adaptability in a distributed AMS and there appears to be considerable potential for AMS within New Zealand{\textquoteright}s pasture-based farming system.},
	issn = {1176-5283},
	author = {Jago J and Copeman P and Bright K and McLean D and Ohnstad I and Woolford M}
}
@conference {41278,
	title = {CowTrakker technology for improved heat detection},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {61},
	year = {2001},
	month = {Jan},
	pages = {172-175},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {Devices designed to detect motion (CowTrakker{\texttrademark}, Bou-Matic, USA) were attached to Holstein-Friesian cows of either NZ or overseas origin. Animals of each strain either grazed pasture or were fed a total mixed ration. Milk samples were collected twice weekly and progesterone content analysed to identify ovulation events. Cows had tail paint applied from 2 weeks after calving, and were observed twice daily at milking for oestrous activity. Recording continued until 6 weeks after the planned start of mating (PSM). Cows were artificially inseminated following a progesterone-based synchrony programme at PSM. CowTrakker{\texttrademark} data were analysed using four algorithms (T3/1, T3/3, T10/1 and T10/3), which varied according to the period of the rolling average used (3 or 10 days) and the standard deviations from that average (1 or 3). These measurements were related to behavioural observations and the occurrence of ovulation. There was a significant number of false positive events detected by the CowTrakker with all algorithms (sensitivity: 12.3, 46.9, 62.3 and 81.5\%; specificity: 67.1, 88.4, 95.4 and 99.0\%, for T3/1, T3/3, T10/1 and T10/3, respectively) as compared to behavioural observations alone (sensitivity: 71.6\%; specificity: 99.6\%). The CowTrakker{\texttrademark} was a useful heat detection aid, but must be used in conjunction with careful behavioural observations in order to interpret the high proportion of false positive events that are recorded.},
	issn = {1176-5283},
	author = {Verkerk GA and Claycomb RW and Taufa VK and Copeman P and Napper A and Kolver E}
}
