@conference {41538,
	title = {The productivity of pasture-based dairy farms in New Zealand with different levels of extra feed input},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {65},
	year = {2005},
	month = {Jan},
	pages = {63-67},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {The objective of this research was to study the physical and financial performance of commercial dairy farms in New Zealand that differed in the amount of extra feed used. Data from Dexcel{\textquoteright}s ProfitWatch corresponding to 626 owner-operated dairy farms between 1998/1999 and 2001/2002 were analysed. The data were classified according to each of the four dairy seasons and the extra feed used per cow. Extra feed comprised supplements imported (hay, pasture silage, maize silage, concentrates and other feeds), winter grazing and maize silage grown on the farm. The statistical analyses were done in SAS and comprised analyses of variance and regression analyses. High feed input farms (H farms, 740-940 kg extra DM /cow/year) had higher stocking rates (2.7-2.8 vs 2.4-2.5 cows/ha), lower comparative stocking rate (83-86 vs 83-92 kg live weight/t DM), and higher milksolids (MS) production per cow (293-341 vs 249-295 kg MS/cow) and per hectare (826-921 vs 616-744 kg/ha) than low feed input farms (L farms, 20 kg DM extra feed/cow/year). The use of nitrogen fertiliser was also higher in the H farms than in L farms (85-116 vs 53-67 kg N/ha/year). There were no significant differences in farm size, herd breeding worth, reproductive characteristics of the herds and estimated pasture consumed per hectare. On average, extra feed was significantly associated with extra cows (0.17 extra cows/ha for 1 t extra DM) and extra milk solids (50 g extra MS/cow for 1 kg extra DM/cow and 96 g extra MS/ha for 1 kg extra DM/ha), but the wide variability is shown by the low values for R2 (0.13 to 0.16 for the three relations above). The H farms produced higher gross farm incomes per hectare (by $0.47 to $0.49/kg extra DM offered) but had higher farm working expenses per hectare (by $0.36 to $0.37/kg extra DM offered), so that Economic Farm Surplus per hectare was not higher for these farms in any year. High management skills and control of costs are necessary for profit to be increased by the use of extra feeds.
KEYWORDS: low-input; high-input; extra feed. },
	issn = {1176-5283},
	author = {Silva-Villacorta D and Holmes CW and Shadbolt NM and Lopez-Villalobos N and Prewer W and Glassey CB and Blackwell M}
}
@conference {41134,
	title = {Performance of dairy cows grazing pastures with or without ergovaline and lolitrem B in Northland.},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {59},
	year = {1999},
	month = {Jan},
	pages = {254-257},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Ergovaline and lolitrem B are alkaloids produced by Neotyphodium endophytes in ryegrass. These toxins are associated with
poor animal performance in many situations but influences on milk production by dairy cows had not been determined in NZ
except for short-term trials. An on-farm trial was set-up at Te Hana to measure milk production responses in 2 groups of 16 cows which were maintained on a) ryegrass-based pastures which contained wild-type endophytes which produced ergovaline and lolitrem B [+Ev] or on b) ryegrass pastures that were either free of endophyte or contained a novel endophyte which did not produce ergovaline or lolitrem B [-Ev]. The trial ran from October 1997 til mid-April 1998 and milk production was recorded for each cow at each milking for 10 consecutive days per month culminating in a herd test. There was no difference in milk production in October and November, but a difference of 25\% developed in December in favour of the -Ev group and substantial differences in production were maintained until the trial was terminated. Effects of ergovaline on cow performance are discussed in relation to environmental and behavioural factors.},
	issn = {1176-5283},
	author = {Keogh RG and Blackwell M and Shepherd P}
}
