@conference {3672,
	title = {BRIEF COMMUNICATION: Metabolite profiling in New Zealand milk},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {75},
	year = {2015},
	month = {07/2015},
	pages = {39-41},
	address = {Dunedin},
	abstract = { },
	issn = {1176-5283},
	author = {Davis SR and Jaine J and Obolonkin V and Braggins TJ and Cooney TP and Scott A and Spelman RJ}
}
@conference {89235,
	title = {Insulin response to a glucose tolerance test in 18-month pregnant heifers as a predictor of subsequent survival},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {73},
	year = {2013},
	month = {Jan},
	pages = {117-119},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {<p>A decline in dairy cow fertility in the USA and in the UK (Beam \&amp; Butler 1999; Royal et al. 2000) has also been noted in New Zealand. Calving rate, the proportion of cows re-calving within the first 42 days of the subsequent seasonal calving period, in New Zealand decreased from approximately 70\% in 1991 to 60\% in 2004 (Harris et al. 2006). There has been no further deterioration in subsequent years.</p>
},
	issn = {1176-5283},
	author = {Hutchinson KJ and Davis SR and MacKenzie DDS and Blair HT and McNaughton LR and Sanders K and Spelman RJ}
}
@conference {89246,
	title = {Quantitative trait loci associated with variation in maximum milk flow rate in Friesian -Jersey cross bred cows},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {73},
	year = {2013},
	month = {Jan},
	pages = {168-170},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {<p>On New Zealand dairy farms, the milking process consumes more than half of the available labour hours (Jago et al. 2010). While some recent research has shown some potential to improve labour efficiency of dairy farms during milking (Jago et al. 2010), the speed of milking is, in large part, dictated by the slowest milking cows in the herd.</p>
},
	issn = {1176-5283},
	author = {Davis SR and Littlejohn M and Ellison R and Spelman RJ}
}
@conference {75905,
	title = {Effect of lactation stage and breed on the concentration of unsaturated fatty acids in milkfat of New Zealand dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {71},
	year = {2011},
	month = {Jan},
	pages = {203-207},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Invercargill},
	abstract = {Milkfat composition influences the nutritional value and manufacturing characteristics of milk. This research studied the influence of: 1) stage of lactation on the concentration of unsaturated fatty acids (UFA) in milkfat of Holstein-Friesian, Jersey and Crossbred cows, 2) segregation of cows according to their UFA concentration in milkfat. The concentration of UFA in milkfat was predicted with a calibration equation using Fourier transform infrared spectroscopy. The data (21,757 test-day records) were analysed using a mixed model with a third-order orthogonal polynomial. In the three breeds studied, after early lactation the concentration of UFA in milkfat decreased steadily as the lactation progressed, but in Holstein-Friesian cows it increased slightly at the end of lactation. Throughout lactation, Holstein-Friesian cows produced milkfat with a higher concentration of UFA than Jersey and Crossbred cows. In each herd, cows were split into a high and a low group according to the average UFA concentration of the herd. The high UFA group had higher (P <0.001) milk yield, but lower (P <0.001) yields and concentrations of fat and protein than the low UFA group. This study indicates that concentration of UFA in milkfat is affected by breed and stage of lactation in New Zealand dairy cattle.},
	issn = {1176-5283},
	author = {Silva-Villacorta D and Lopez-Villalobos N and Blair HT and Hickson RE and Spelman RJ and Melis J and Davis SR and Berry SDK and Lehnert K and Snell RG}
}
@conference {75888,
	title = {Genetic analysis of incidence of recorded clinical lameness in New Zealand dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {71},
	year = {2011},
	month = {Jan},
	pages = {126-130},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Invercargill},
	abstract = {Herd records from 76,357 cows, collected during the 2005/06 to 2008/09 milking seasons from 155 herds in the Livestock Improvement Corporation (LIC) young sire progeny test scheme, were used to estimate genetic parameters and breed effects for incidence of recorded clinical lameness (RCL) in Holstein-Friesian, Jersey and crossbred dairy cattle. RCL was coded "1" for cows that presented at least one event of RCL at any day during the season and "0" for cows without RCL. Genetic parameters were estimated with a repeatability animal model across breeds. The average incidence of RCL per herd was 6.3\% and ranged from 2\% to 34\%. Jersey cows had significantly (P <0.05) lower incidence (6.0\%) than Friesian cows (6.8\%) but similar to crossbred cows (6.1\%). The heritability estimate for incidence of RCL was 0.016 {\textpm} 0.003 (standard error) while the repeatability was 0.071 {\textpm} 0.005. Sire estimated breeding values for RCL ranged between -5 and 8\% with Jersey sires showing the lowest values. These results suggest that selection for resistance to lameness will result in a low rate of genetic gain but using Jersey sires can be an alternative to increase genetic resistance to lameness in New Zealand dairy cattle.},
	issn = {1176-5283},
	author = {Chawala AR and Lopez-Villalobos N and Margerison JK and Spelman RJ}
}
@conference {69516,
	title = {Application of genomic information in a dairy cattle breeding scheme},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {70},
	year = {2010},
	month = {Jun},
	pages = {253-256},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {Marker assisted selection has been applied in dairy cattle breeding schemes over the last decade with minor to moderate improvements in genetic gain. In most cases, the cost effectiveness of marker assisted selection has been neutral, at best. The completion of the sequencing of the bovine genome in 2006 has generated a large number of single nucleotide polymorphisms that has allowed the application of genomic selection. In addition, the cost of genotyping single nucleotide polymorphisms is considerably lower than microsatellite genotyping. Livestock Improvement Corporation has undertaken extensive genotyping of the sires that have been progeny tested in the last 20 to 30 years. Analysis of these data by Livestock Improvement Corporation researchers has identified combinations of markers that were used to obtain genetic evaluation of bulls from their DNA. By utilising this genomic information, semen from two-year-old sires has been sold to New Zealand dairy farmers. Over the past two years, the genomically selected bulls have accounted for approximately 15 to 20\% of the inseminations. It is expected that selection based on genomic information, termed genomic selection, will increase the rate of genetic gain in New Zealand by 30 to 50\%.},
	issn = {1176-5283},
	author = {Spelman RJ and Arias J and Keehan M and Obolonkin V and Winkelman A and Johnson D and Harris BL}
}
@conference {69523,
	title = {Deer Improvement{\textquoteright}s breeding scheme for venison production in red deer (Cervus elaphus)},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {70},
	year = {2010},
	month = {Jun},
	pages = {278-282},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {This paper describes the progress of the Deer Improvement breeding scheme that has been in place since 2004. The aim of the programme is to improve venison production through genetic selection for growth rate of lean meat with improved fertility, temperament and mature hind weight. The breeding programme currently comprises 500 hinds bred from stags selected for high growth rate with the intention of increasing hind numbers to over 1,000. This projected increase will be facilitated by the use of embryo transfer to multiply the genes of the top ranked yearling animals, thus shortening the generation interval. As part of the programme, all progeny are DNA parentage tested, weighed frequently during their first 12 months of life and temperament scored. Pregnancy and weaning rates are recorded in the nucleus and progeny testing herds. As a result of selection during the past six years, the average yearling weight has increased by 1.5 kg/yr over all farms involved in the breeding programme. In 2009, male fawns from the nucleus herd reached an average of 100 kg at seven months of age. This is greater than the current industry average of 75 to 78 kg for the same age.},
	issn = {1176-5283},
	author = {Quinn-Walsh EG and Johnson DL and Chardon J and Spelman RJ}
}
@conference {69514,
	title = {Genetic analysis of incidence of clinical mastitis in New Zealand dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {70},
	year = {2010},
	month = {Jun},
	pages = {246-249},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Palmerston North},
	abstract = {The aim of the study was to estimate breed and geneticeffects on the incidence of clinical mastitis (CM) in New Zealand dairy cattle. Records of CM collected during seasons 2005-06 to 2008-09 from 53,419 cows of different breeds including Holstein-Friesian (H-F), Jersey (J) and Crossbed (HF x J), were analysed. Clinical mastitis was coded {\textquotedblleft}1{\textquotedblright} for cows that presented at least one event of CM at any day at risk during the season and {\textquotedblleft}0{\textquotedblright} for cows without CM. Genetic parameters and breed effects for the incidence of CM were estimated with a repeatability animal model across breeds using restricted maximum likelihood methodology. The cumulative lactation incidence of CM was 11\% in92,961 lactations. Heritability and repeatability for incidence of CM were 0.015 {\textpm} 0.003 and 0.070 {\textpm} 0.005, respectively. Jersey cowshad 2.9\% less incidence of CM than H-F cows. Heterosis effect of H-F x J was minus 11.7\% of the average of the parental breeds. Results from this study confirm previous estimates ofgenetic parameters for CM. Sire variation and breed and heterosis effects were significant and can be exploited in a breeding program to improve resistance to CM in New Zealand dairy cattle.},
	issn = {1176-5283},
	author = {Jury K and Lopez-Villalobos N and Spelman RJ and Arias J and Heuer C}
}
@conference {60943,
	title = {Breed effects for lactoferrin concentration determined by Fourier transform infrared spectroscopy},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {69},
	year = {2009},
	month = {Jun},
	pages = {60-64},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {A calibration equation based on partial least squares using Fourier transform infrared spectroscopy (FTIR) data was derived to predict concentration of lactoferrin (Lf) in bovine milk. The concordance correlation coefficient of the calibration equation was estimated at 0.81 using 246 milk samples collected in the 2003-04 season from second-parity crossbred cows during late lactation. The calibration equation was then used to predict the concentration of Lf (pLf) in 9,742 milk samples from 814 Holstein-Friesian (HF), 955 Jersey (J) and 842 crossbred HF x J cows sampled on average 3.7 times during the 2007-08 season. A repeatability animal model was used to obtain breed effects and estimates of variance components for pLf. Concentrations of pLF (mg/L milk) were significantly (P <0.001) different between breed groups (HF = 163 {\textpm} 3.8, HF x J = 175 {\textpm} 5.0 and J = 193 {\textpm} 6.3). Heritability and repeatability of pLf concentration were 0.16 {\textpm} 0.036 and 0.35 {\textpm} 0.012, respectively. These results confirm previous studies showing that Lf concentration in milk can be predicted using FTIR spectroscopy and that there are significant breed differences and animal variation that can be exploited in a breeding program. },
	issn = {1176-5283},
	author = {Lopez-Villalobos N and Davis SR and Beattie EM and Melis J and Berry S and Holroyd SE and Spelman RJ and Snell RG}
}
@conference {42057,
	title = {Testing for quantitative trait loci for lactation persistency in dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {68},
	year = {2008},
	month = {Jan},
	pages = {107-110},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Brisbane, Australia},
	abstract = {Lactational persistency has not been selected for in New Zealand dairy populations. Existing milk production data and pedigrees from New Zealand Holstein-Friesian cattle at pasture, recorded in the Livestock Improvement Corporation database were utilized with a grand-daughter design, for a genome-wide search for a quantitative trait locus for persistency of lactation. Persistency was defined as a weighted sum of test-day yields. A significant region was identified in one grandsire family on Chromosome 3 at microsatellite marker position AGLA247 (chromosomal position 67cM; P <0.05). To verify this result, data from a research dairy herd defining persistency as the mean of three weekly tests of daily yield in March (late lactation) divided by the equivalent daily yields in October (early lactation)) for three seasons beginning in 1997/98 were used in a phenotypic association study on Chromosome 3 only. One allele of marker HUJ246, close to the original region appeared to show an additive effect. The maximal difference between this genotype and the others at this marker locus was 12.3 {\textpm} 4.4\% of the mean persistency. The potential use of this marker in the New Zealand dairy cattle population depends on the current allele frequencies in the industry. },
	issn = {1176-5283},
	author = {Morris CA and Spelman RJ and Henderson HV and Cullen NG and Hyndman DL and Miller FM and Johnson DL and Molenaar AJ and Grigor MR and Davis SR}
}
@conference {41714,
	title = {Hair whorl patterns are related to age at puberty and milk-production traits in dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {67},
	year = {2007},
	month = {Jan},
	pages = {130-135},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Wanaka},
	abstract = {The objective of this study was to measure facial hair whorl characteristics of Friesian-Jersey crossbred cows (n=658) and to investigate their association withmeasures of milk production, fertility and behaviour. Cows had 1 (n=581), 2 (n=10), 3 (n=1) or no facial hair whorls (n=66). Of those cows with one whorl, 66\% had whorls in the middle of the head, whereas 21\% had whorls low on their head and 13\% high on their forehead. Round whorls were present on 77\% of cows, while 23\% had non-round whorls. Fifty five percent of cows with round whorls were recorded as havinganticlockwise rotation and 16\% of cows as clockwise rotation. Cows with high hair whorlstended to reach puberty earlier on average than cows with lower whorls (P=0.07). Cows with higher non-round whorls also produced lower total milk and total solid yields, than cows with low whorls (P=0.01). No relationship was found between hair whorl characteristics and behaviour in this study.},
	issn = {1176-5283},
	author = {Young SK and McNaughton LR and Spelman RJ}
}
@conference {41973,
	title = {Prospects for genome wide selection in the New Zealand livestock industries},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {67},
	year = {2007},
	month = {Jan},
	pages = {162-168},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Wanaka},
	abstract = {A number of DNA marker applications aid genetic selection within subpopulations of New Zealand{\textquoteright}s livestock farming industries. Advances in genomic tools have opened the possibility of genotyping individuals for a large set of markers, enough to have a large proportion of the genome {\textquoteleft}tagged{\textquoteright} with at least one of these markers. This creates opportunities for genome wide selection (GWS) {\textendash} the selection of breeding animals based on very large numbers of marker genotypes. There are a number of requirements for GWS to work, including the existence of genotyping technology to provide genotypes at a sufficient density, tractable statistical methods for estimating marker  effects to use in prediction models and suitably phenotyped populations which when genotyped allow estimation of relationships between markers and traits. Additional phenotyped populations are required to validate their predictive ability and demonstrate economic benefits to breeders and to the commercial tier. A high density genotyping platform is available for cattle, but may need further developments. Plans are underway for a similar platform for sheep, but not for deer. The dairy industry is well placed to implement GWS, as there is a large bank of DNA samples of industry sires representing most of the genome variation present. Genotyping these animals will allow marker effects to be estimated and the reduced generation interval arising from selecting young sires should easily overcome any decrease in selection accuracy compared with progeny testing. Industry structures are likely to evolve to allow a return to entities undertaking GWS. GWS will be mostbeneficial for traits with low heritability, that cannot be measured on selected parents and/or that are expensive to measure. Genes of known effect may continue to be accounted for individually, particularly if they exhibit non-additive effects.},
	issn = {1176-5283},
	author = {Dodds KG and Amer PR and Spelman RJ and Archer JA and Auvray B}
}
@conference {41617,
	title = {Responses and factors affecting intramammary infection rates resulting from infusion of a Streptococcus uberis strain in Friesian - Jersey crossbred cows},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {66},
	year = {2006},
	month = {Jan},
	pages = {70-76},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Napier},
	abstract = {The objective of this study was to investigate responses to an intramammary infusion of a Streptococcus uberis strain in 264 Friesian-Jersey cows, and identify factors contributing to clinical mastitis risk in the week following infusion. Factors examined for their contribution to risk include sire, days in milk at the time of infusion, SCC on the morning of infusion, previous mastitis treatment history, and the presence of any major pathogens at the time of infusion. Prior to infusion, milk samples were collected from all glands for bacteriology assessment, and antibiotic treatments were administered to clear infections. A single gland from each cow was infused with an average 104 colony-forming units (sd=22) of Streptococcus uberis, and milk samples were collected at each milking for the subsequent 13 milkings, or until diagnosis of clinical mastitis. Logistic regression and survival analysis were used to determine risk factors. Findings showed that cows with a somatic cell count at infusion of >=100,000 cells/ml had a lower incidence of clinical mastitis (18.3\% vs. 81.5\%; p<0.0001). Results also indicated that the presence of Staphylococcus aureus at infusion for cows that had no pre-infusion mastitis treatment(s) was associated with a lower incidence of clinical mastitis (29.0\% vs. 82.8\%; p<0.0001). },
	issn = {1176-5283},
	author = {Sanders KM and McDougall S and Stanley GE and Johnson DL and Spelman RJ and Harcourt SJ}
}
@conference {41838,
	title = {Estimation of lactation persistency in crossbred grazing dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {65},
	year = {2005},
	month = {Jan},
	pages = {300-305},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {Lactation persistency is commonly referred to as the rate of decline in daily yield after the peak of lactation and can be measured in different ways. The objective of this study was to calculate different measures of persistency for milk traits and estimate the correlations between parameters of the lactation curve in crossbred cattle. Herd test records of milk, fat, protein and lactose from 810 first lactation cows were used to obtain individual lactation curves using a mixed model fitting six knots splines. The model included the fixed effects of contemporary group (year-calving week), sire, age at calving (linear and quadratic) and an average spline and the random effect of cow-spline interaction. All cows were in their first lactation, second cross Friesian x Jersey from a crossbreeding experiment established for quantitative trait loci identification. Persistency was measured in three different ways: P1, slope of the line fitted using linear regression of daily yield on day of lactation from day 60 to day 220; P2, the area under the lactation curve from day 121 to 180 divided by the area under the curve from day 1 to 60; and P3, the 240-day lactation yield divided by peak yield multiplied by 240. Correlations between measurements of persistency ranged from 0.24 to 0.81 and were significantly different to zero (P < 0.001). Correlations between lactation yield and measurements of persistency ranged from -0.43 to +0.33 and were significantly different to zero (P < 0.01). These results indicate that measurements of persistency are not invariant and highlight the need to calculate persistency in a more consistent way. When cows were classified for persistency P2 of fat plus protein, cows of high persistency (top 25\%), compared with cows of low persistency (bottom 25\%), had significantly (P < 0.05) more days in milk, higher total yields of milk and its components, lower peak yields, later day of peak yield and lower rate of decline in daily yield from day 60 to day 220 (P1), but similar 240-day total yield of fat and protein. Farming cows of high persistency may be an alternative to reduce farm investments in peak notes and risks of metabolic problems and reproductive failures.
KEYWORDS: lactation persistency; milk yield. },
	issn = {1176-5283},
	author = {Lopez-Villalobos N and Spelman RJ and Harris BL and Stanley G and Harcourt S}
}
@conference {41850,
	title = {Factors affecting methane production in Friesian x Jersey dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {65},
	year = {2005},
	month = {Jan},
	pages = {352-355},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {Methane production was measured in 301, 3-year-old Friesian x Jersey dairy cows, during summer 2004 in stage one of a project to define phenotypes for quantitative trait loci (QTL) mapping and to investigate the relationships between CH4 and milk production. Animals were allocated into four groups and their methane production was measured during four days. Feed intake was estimated by the alkane technique and by prediction equations. Correlations between the alkane technique and prediction equations were all less than 0.37, but correlations amongst the prediction equations were greater than 0.61. Daily CH4 output varied from 210 to 498 g and averaged 332 g. Dry matter intake averaged 19.3 g/kg DM. Milk production and live weight gain were negatively related to CH4 production per kg dry matter intake. Sire was not found to have a significant effect on CH4 output per kg of dry matter; however, only six sires are represented in the trial. The CH4 output recorded in the current study was within the ranges observed in other studies and was repeatable between days. High quality data were generated for the QTL study.
KEYWORDS: methane; herbage intake; alkanes; dairy cows. },
	issn = {1176-5283},
	author = {McNaughton LR and Berry DP and Clark H and PinaresPatino C and Harcourt S and Spelman RJ}
}
@conference {41480,
	title = {Friesian Jersey crossbred trial: Generating phenotypes for the discovery of quantitative trait loci},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {64},
	year = {2004},
	month = {Jan},
	pages = {92-95},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {The breeding of improved varieties of agriculturally important species requires constant effort and innovation. The ways we in New Zealand use emerging technologies to maintain our low-cost, low-input, sustainable, pastoral agricultural systems are extremely important. When it comes to developing elite varieties and strains of ryegrass we have been, until very recently, disrupting  much to achieve little: we rely on chance to find the right combinations of traits in our breeding lineages, whether animal germplasm or plants cultivars. The use of Cisgenics{\AE}, where heritable material is moved only within a species by either traditional or modern biotechnological means offers a better way for  ryegrass breeding in line with a key principle of science and economics.},
	issn = {1176-5283},
	author = {Spelman RJ and Hooper JD and Stanley G and Kayis SA and Harcourt S}
}
@conference {41484,
	title = {Influence of material and sire effects on antibody response following clostridial vaccination of Friesian-Jersey crossbred calves},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {64},
	year = {2004},
	month = {Jan},
	pages = {110-114},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {As part of an ongoing project to identify quantitative trait loci (QTL) for economically important traits in New Zealand dairy cows, a vaccine trial was conducted to measure the antibody response of 10 week old Friesian-Jersey crossbred calves to two antigenic compounds of a clostridial vaccine (Clostridium novyi B and Clostridium tetani toxoids). Blood samples were collected from 469 calves prior to vaccination at 10 weeks of age, prior to re-vaccination at 13 weeks of age and at 16 and 22 weeks of age. ELISA assays using conjugated rabbit anti-bovine IgG were conducted for both toxoids. Correlations and explanatory variables were calculated using correlation and general linear model (GLM) procedures in SAS. Antibody response to both toxins were relatively low after the first vaccination (week 13), but were boosted to high levels after revaccination (week 16). GLM analysis revealed a moderate sire effect contributing to the variability seen in the 13 week test against C. tetani (P=0.001) and the 16 week test against C. novyi (P=0.01). This variation in individual antibody response will be used in future research to identify genetic factors controlling the acquisition of immunity. },
	issn = {1176-5283},
	author = {Harcourt SJ and Buddle BM and Hamel K and McNaughton LR and Spelman RJ}
}
@conference {41216,
	title = {Experimental design for detection of quantitative trait loci for Facial Eczema in dairy cattle},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {60},
	year = {2000},
	month = {Jan},
	pages = {281-283},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {Three hundred and fifty farmers involved in the Livestock Improvement Corporation Sire Proving scheme (SPS) were surveyed, in May 1999, on the incidence of Facial Eczema (FE) in their herds. The SPS farmers were asked to score their 2- and 3-year-old SPS daughters on a five point scale; 1=not affected, 2=slightly affected, 3=severely affected (still alive), 4=culled due to FE and 5=died due to FE, and to comment on any calves or yearlings that were in categories 3 to 5. In the herds with at least one case of FE (50\% of respondees), 89\% of the animals were not affected, 5\% were slighty affected, 5\% severely affected and 1\% were either culled or died primarily from FE. Heritabilities of 3-17\% verified that FE in this dataset was controlled in part genetically and with the DNA bank for all SPS daughters, enables a QTL study to be undertaken. The proposed experimental design is an association study with the pooling of DNA for the 516 daughters that were scored 3 or higher. The control for the experiment would be paternal half sibs for each of the {\textquoteleft}affected{\textquoteright} daughters from the same herd, if possible. To detect linkage disequilibrium (LD) a panel of some 1000 microsatellites would be genotyped.},
	issn = {1176-5283},
	author = {Spelman RJ and Sellars MD and Sanders K}
}
@conference {40989,
	title = {Effects of selection and crossbreeding on industry returns from whole milk powder, butter and casein in the New Zealand dairy industry},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {58},
	year = {1998},
	month = {Jan},
	pages = {64-67},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {The effects of selection and crossbreeding on New Zealand dairy industry return were evaluated with a deterministic simulation model over 25 years. Several crossbreeding strategies involving Holstein-Friesian (F), Jersey (J) and Ayrshire (A) cattle were evaluated. These strategies were straightbreeding, upgrading to F (UPGF), upgrading to J (UPGJ), upgrading to A, and two- and three-breed rotational crosses. Total production of milk, fat, protein, lactose and ash were calculated assuming that 12,000 kg dry matter/ha was eaten for 1,224,911 ha. Yields of standardised whole milk powder (WMP), casein and butter were calculated. For the base year all the protein was utilised in WMP and for subsequent years, some increases in protein were sold in the form of casein. Casein and WMP were valued at $6.00 and $3.31 per kg respectively over the 25 years, whereas butter was valued at $3.00 per kg for base year production levels and $0.45 per kg for marginal increases in production. Production for the base year was 9,874 million l milk, 467 million kg fat, 359 million kg protein and 464 million kg lactose which yielded 1,263 million kg WMP and 157 million kg butter for an industry return of $4,646 million. Relative to the base year, UPGF resulted in the largest increase in WMP (128 million kg, 10\%), the lowest increase in casein (36 million kg) and increased returns by $639 million (14\%). UPGJ resulted in the lowest increase in WMP (73 million kg, 6.0\%), the largest increases in butter (67 million kg, 43\%), casein (65 million kg) and returns ($662 million, 14\%). Two-breed rotational (F,J) resulted in product flows for WMP and butter that were above the intermediate between UPGF and UPGJ but return that was equal to UPGJ. Selection within-breed in combination with crossbreeding can increase industry returns. However, the net financial outcome of all changes must be assessed taking into account farm expenses, income from culled stock and factory costs in processing milk with different composition in order to determine optimum crossbreeding strategies. },
	issn = {1176-5283},
	author = {Lopez-Villalobos N and Garrick DJ and Spelman RJ and Holmes CW and Blair HT}
}
@conference {40761,
	title = {Potential for profitable use of DNA markers in the New Zealand Dairy Industry},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {56},
	year = {1996},
	month = {Jan},
	pages = {9-11},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = { Annual genetic advance in merit of dairy cattle can be assessed from  selection in four pathways: Bulls to breed Bulls (BB); Cows to breed Bulls  (CB); Bulls to breed Cows (BC); and Cows to breed Cows. It is usually  assumed that breeding merit is determined by actions of a very large number  of genes, each having a small effect (infinitesimal model of inheritance). In  practice, the number may be finite, with a few genes (known as QTLs)  having large effects. DNA technologies allow young animals to be tested  for particular QTLs using markers. Benefits of marker assisted selection were calculated for one additive QTL  over a range of sizes (allele values of 0.25, 0.38, or 0.5 genetic s.d.) and  initial gene frequencies (0.01, 0.10, 0.35). Testing was conducted in the BB,  BC and CB pathways. Strategies were compared using the Net Present  Value of the stream of productive benefits less costs for a 30 year horizon,  assuming one genetic s.d. is worth $160. Superior rates of advance were sometimes achieved at greater cost than  benefits. At a cost of $10 per genotype assessment it was never profitable to  genotype small QTLs. The largest QTL could be profitably used to screen  young bulls before progeny testing except at the lowest starting frequency.  In some circumstances, selection for a QTL resulted in improved medium  term response but reduced long-term response. Knowledge of the size and  frequency of QTLs and a pre-defined time horizon will be essential to  discriminate between profitable and costly applications of this technology. },
	issn = {1176-5283},
	author = {Garrick DJ and Spelman RJ}
}
