@conference {3672,
	title = {BRIEF COMMUNICATION: Once-a-day milking with supplemented cows in Argentina},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {77},
	year = {2017},
	month = {06/2017},
	pages = {61-63},
	address = {Rotorua},
	abstract = {Dairy farming is an important activity in Argentina. The country produced over 11,000 million litres of milk in 2015 (Ministerio de Agroindustria 2015). Milk production is based on the utilisation of grazed lucerne pastures (Medicago sativa L), and the use of supplements such as silage, hay and concentrate feeds. Pasture comprises between 30\% and 50\% of the diet. Average milk production per cow is 5,900 kg/cow per year (equivalent to 401.2 kg of milk solids/cow per year; INTA 2015). Due to a favourable ratio between milk price and concentrate feeds price (average ratio milk to concentrate price over 1.5), dairy farmers in Argentina include great amounts of concentrate feeds in their systems. Over 95\% of dairy herds of Argentina are Holstein, and cows are milked twice a day (TAD) (FAO 2011).

In the last decade, studies have been conducted, mainly in New Zealand, but also in Europe, to evaluate the effects of once-a-day (OAD) milking during the whole lactation (Stelwagen et al., 2013). Lifestyle benefits for farmers and employees and improvement in animal health and reproductive performance are the main motivations to choose OAD milking (Bewsell et al., 2008)...},
	issn = {1176-5283},
	author = {Lazzarini B and Peluffo L and Lopez-Villalobos N and Hendrikse L and Baudracco J}
}
@conference {75908,
	title = {Efficiency, cheese yield and carbon emissions of Holstein-Friesian, Jersey and crossbred cows: an overview},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {71},
	year = {2011},
	month = {Jan},
	pages = {214-218},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Invercargill},
	abstract = {This paper provides an overview on differences between Holstein-Friesian (HF), Jersey (J) and crossbred cows, for feed conversion efficiency (FCE), dry matter intake (DMI), cheese yield and carbon emissions. It was found that J cows have significantly higher DMI per kilogram of live weight (LWT) compared to HF and F1 HFxJ cows (3.64, 3.81 and 3.23 g DMI/kg LWT, respectively). A higher DMI per kilogram of LWT can result in more energy available for milk production, assuming that the maintenance requirements per unit of LWT are equal between the breeds. Estimates of FCE measured as grams of milksolids (milkfat plus milk protein) per kilogram of DMI were higher in J than HF cows (112 vs 97 g MS/kg DMI) in the reviewed papers. For grazing cows, a higher proportion of feed consumed is converted into milk production than used to cover maintenance energy requirements in J cows. This may result in lower greenhouse gas emission intensity from J than HF cows. Opportunities for the utilisation of breed differences to increase FCE and reduce carbon footprint and increase overall farm profitability in grazing dairy systems requires further farming system research to elucidate the relative efficiencies of the most common dairy breeds.},
	issn = {1176-5283},
	author = {Sneddon NW and Lopez-Villalobos N and Baudracco J}
}
@conference {69476,
	title = {Prediction of herbage dry matter intake for dairy cows grazing ryegrass-based pastures},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {70},
	year = {2010},
	month = {Jun},
	pages = {80-85},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {A model that combines theoretical and empirical equations was developed to predict daily dry matter intake (DMI) for Holstein-Friesian (HF) cows grazing ryegrass-based swards and offered differing levels of concentrate supplementation. An upper limit to potential herbage dry matter (DM) intake at grazing was set, which is the lower of three limits set by either physical (rumen fill), metabolic (energy demand) or grazing restrictions. Potential herbage DMI at grazing and the herbage allowance were then used to predict herbage DMI, of cows fed only pasture, using an empirical algorithm. If supplements are fed, substitution rate was predicted to calculate actual herbage DMI. An independent dataset, with individual herbage DMI measurements (n = 1,147) of three strains of lactating HF cows, was used to validate the model. Data within strains were averaged for every month of lactation, allowing 27 data points for validation. The fitness of the model was satisfactory, with a relative prediction error (RPE) of 0.083 and a concordance correlation coefficient (CCC) of 0.74. Herbage DMI was simulated for HF cows of different genotypes fed different levels of concentrate supplementation at different herbage allowances. The model successfully predicted herbage DMI of grazing cows under different combinations of nutritional, physiological and genetic variables.},
	issn = {1176-5283},
	author = {Baudracco J and Lopez-Villalobos N and Holmes CW and MacDonald KA}
}
@conference {41611,
	title = {Development of a model to predict pasture intake for grazing dairy cows in Argentina},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {66},
	year = {2006},
	month = {Jan},
	pages = {35-41},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Napier},
	abstract = {The nutritional value of legumes for high milk production is seldom captured because grazed dairy pastures in NZ typically contain insufficient legume tosatisfy the cows{\textquoteright} requirements. This paper reports interim results from a project investigating novel methods of forage presentation to cows, to enhance the contribution of legume to their diet. Four groups ofspring-calving cows (n=5) in late-lactation were allocated to four treatments in a balanced, cross-over design. Two treatments consisted of spatial and temporal arrangements of grass and white clover allocatedto cows as follows: i) continuous free access to grass and white clover growing separately as side-by-sidemonocultures (G/C) and ii) grass-only at {\textquoteright}night{\textquoteright} between the afternoon and morning milking and clover-only during the {\textquoteright}day{\textquoteright} between morning and afternoon milking (GnCd). These were compared against controlsof iii) a typical mixed ryegrass-white clover pasture (Mix; an industry standard) and iv) a ryegrass-only pasture (Grass; a forage standard). Cows grazed each treatment for 8 days before moving to the next treatment in the pre-determined sequence. Measurements included milk production and composition, the time spent grazing during the day and the night (separately for grass and white clover in G/C) and the concentrations in the milk of skatole and indole, as metabolic indicators of nutrient acquisition and utilisation in the contrasting forage treatments. Cows offered G/C or GnCd produced 19.4 and 17.9 kg milk/cow/day, respectively, compared with 15.0 and 14.6 kg/cow/day when offered Mix or Grass, respectively (P=0.01, SEM=0.74). The diurnal distribution of grazing was influenced by pasture treatment (treatment x  time interaction P <0.001). Cows on G/C grazed proportionately more at {\textquoteleft}night{\textquoteright} and cows on GnCd proportionately less at {\textquoteleft}night{\textquoteright} compared with Grass or Mix. GnCd constrained the cows to spend less time grazing clover than those offered G/C (245 vs. 408 mins grazing clover during 24 hrs) and more time grazing grass (253 vs. 105 mins in 24 hrs). The apparent {\textquoteright}restriction{\textquoteright} in GnCd to grazing clover-only during the day did not significantly reduce milk yield compared with G/C. The spatial and temporal allocations of grass and clover affected the concentrations of indolic compounds in PM and AM milk, suggesting there is scope to improve the efficiency of protein utilisation in the rumen.},
	issn = {1176-5283},
	author = {Baudracco J and Lopez-Villalobos N and Holmes CW and Brookes IM and Kemp P and Comeron E and Romero LA and Horan B and Dillon P and Berry D}
}
