@conference {3672,
	title = {Comparison of health and reproductive treatments over three seasons for once-a-day and twice-a-day milking herds},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {77},
	year = {2017},
	month = {06/2017},
	pages = {211-215},
	address = {Rotorua},
	abstract = {Once-a-day (OAD) milking has been increasing in popularity in New Zealand, while housing cows is being advocated as one means of minimising environmental impacts of dairying. The present study aimed to investigate health treatments under four different farming systems: OAD, and three twice-a-day (TAD) systems (housed, standard and commercial). There were health records from 377 cows milked OAD and 878 cows milked TAD, over the dairy seasons 2013-14, 2014-15 and 2015-16. Data were analysed assuming binomial distributions for the dependent variables with a generalised linear model that included the effects of season, system (OAD, TAD systems), breed and lactation number. In 2014-15, cows milked OAD were treated less often for mas-titis than cows milked TAD (12\% and 25\% respectively; P<0.05). Cows milked OAD had fewer reproductive treatments compared to cows milked TAD (standard) in 2014-15 and 2015-16 (1\% vs 39\% and 2\% vs 40\% respectively; P<0.01). These results support the advice to farmers that milking OAD does not have a major impact on the risk of mastitis but may provide benefits in terms of reproductive performance. In addition, cows milked TAD (housed) had 13\% of the cows treated for lameness compared to 7\% of cows milked TAD (standard) (P<0.01). },
	issn = {1176-5283},
	author = {Van Der Spek P and Sneddon NW and Lopez-Villalobos N and Donaghy DJ and Laven RA and Mueller KR and Amoore J and Doohan H}
}
@conference {3672,
	title = {Colostral immunoglobulin G as a predictor for serum immunoglobulin G concentration in dairy calves},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {75},
	year = {2015},
	month = {07/2015},
	pages = {3-8},
	address = {Dunedin},
	abstract = { Feeding newborn calves high-quality colostrum is of well-recognised importance as calves that do not receive an adequate
concentration of immunoglobulin-G (IgG) have an increased risk of morbidity and mortality. This experiment aimed to characterise
IgG concentrations in colostrum from the first milking in New Zealand dairy cows, examine IgG status of calves, and to evaluate
the use of a refractometer for estimating quality of colostrum in terms of IgG concentration. Heifer calves entered the calf shed at
0-24 hours of age and were fed pooled first-milking colostrum within eight hours of entering the shed. Blood samples were taken
the following morning. Cows were individually milked and samples from individual and pooled colostrum were analysed. IgG
concentration of serum and colostrum samples were determined by turbidimetric immunoassay. IgG concentration was adequate
according to commercial reference ranges in 70.1\% of individual colostrum, 80.0\% of pooled colostrum and 82.5\% of calf serum
samples. There was no relationship between calf serum and IgG concentration in dam or pooled colostrum. The refractometer was
a good predictor of IgG concentration in serum (r=0.64, P<0.0001) and colostrum both in dam (r=0.87, P<0.0001) and pooled
(r=0.81, P<0.0001) samples. The relationship between IgG concentration and refractometer reading indicates that it could be a
useful on-farm tool.},
	issn = {1176-5283},
	author = {Coleman LW and Hickson RE and Amoore J and Laven RA and Back PJ}
}
