@conference {41310,
	title = {Effects of time-of-calving on dairy production: a farmlet study},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {62},
	year = {2002},
	month = {Jan},
	pages = {42-43},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {Most dairy cows in New Zealand are calved just prior to spring in order to maximise pasture utilisation. This practice is associated with marked irregularities in the volume and composition of milk supplied to factories, which is a major limitation of seasonally-calving, pasture-based dairying systems. The need to accommodate peak milk flow means that manufacturing plants are underutilised for most of the season. Further, changes to milk composition can make it difficult to manufacture dairy products of high quality during some parts of the season, which necessitates the storage of product to meet out-of-season demand.
Such irregularities are caused by a number of factors, including nutritional factors associated with the changing quality and availability of pasture, and physiological and hormonal factors associated with the stage of lactation of the cows (Auldist et al., 1997). One way of manipulating the lactation curve of the cows may, therefore, be to adjust the time of the year at which calving occurs. A previous study in New Zealand showed that autumn calving herds could be as profitable as spring calving herds (Garcia et al., 1998). In that study, nutritional demands were matched with pasture availability by adjusting stocking rate and feeding varying amounts of pasture and maize silage when required. A premium for winter milk was also applied.
The current study was designed to investigate the effects of calving at four different times of the year on milk production in farmlet systems which were otherwise similar in stocking rate and other farm management variables. },
	issn = {1176-5283},
	author = {Audlist MJ and MacDonald KA and Thomson NA and Coulter M and Lancaster JAS and Penno JW}
}
@conference {41358,
	title = {Salt supplementation of lactating cows},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {62},
	year = {2002},
	month = {Jan},
	pages = {236-239},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {<p>Increased intensification of dairy production has contributed to a decrease in the sodium (Na) status of soils throughout New Zealand. This decline has the potential to detrimentally affect animal health and production. A trial was established to determine whether milk production responses would be obtained to sodium supplementation of cows receiving about 0.1\% (0.06-0.14\%) Na in pasture. The cows were in mid-lactation and were randomly allocated to either the control group or a group receiving 14 g Na/cow/day. Supplementation with 14 g Na did not increase milk yield or affect milk composition and there was no interaction with stocking rate. Serum Ca, Mg, Na, and Cl concentration were not affected by treatment, but serum K concentration decreased with Na supplementation. In summary: 0.1\% Na in the diet is sufficient for mid-lactation dairy cows producing 10-12 litres milk/cow/day (0.9 kg milksolids/cow/day) and a milk production benefit will not be achieved through Na supplementation.</p>},
	issn = {1176-5283},
	author = {MacDonald KA and Lile JA and Lancaster JAS and Coulter M and O{\textquoteright}Connor MB}
}
@conference {41116,
	title = {Increasing milksolids production with supplementary feeds},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {59},
	year = {1999},
	month = {Jan},
	pages = {188-191},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {Four farmlets were established at a stocking rate of 4.41 Friesian cows per hectare to compare rolled maize grain, maize silage and a nutritionally balanced ration as supplementary feeds for grazing dairy cows, for three complete seasons. Supplements were offered whenever it was estimated the herds were eating less than 15 kg DM/cow/day or were leaving a post-grazing residual herbage mass of less than 1800 kg DM/ha. Offering 1.3 to 1.5t DM/cow/year of supplement increased net herbage accumulation from 18.3 to 19.2 t DM/ha, however, this did not result in higher annual herbage intake. The use of rolled maize grain, maize silage, and balanced ration supplements increased production from 1188 kg milksolids (MS)/ha to 1763, 1602, and 1769 ({\textpm}69.6) kg MS/ha/year, with responses of 98, 77, and 99 g MS/kg DM, respectively. The magnitude of the response to the supplementary feed was directly proportional to the increase in metabolisable energy supplied by the supplement. Full lactation responses to supplementary feeds were two fold greater than those measured in short term feeding trials. Responses of 7.5g MS/MJME can be expected over the complete lactation when supplements are offered to dairy cows grazing restricted pasture. },
	issn = {1176-5283},
	author = {Penno JW and McGrath JM and MacDonald KA and Coulter M and Lancaster JAS}
}
