@article {3672,
	title = {Factors that may lead to heat-stress in pigs during road transport},
	journal = {New Zealand Journal of Animal Science and Production},
	volume = {82},
	year = {2022},
	month = {01/2022},
	pages = {1-6},
	address = {Online},
	abstract = {A preliminary observational study was undertaken to examine the effect of road transport on finisher pigs that were being transported to an abattoir in New Zealand. Temperature and humidity within a stock-truck were recorded during multiple trips over a three-year period and a video camera was employed to observe the behaviour of the pigs that were being transported. The videos produced were used to establish the times at which open-mouth breathing (OMB; an indicator for heat-stress in pigs) commenced. The videos revealed that OMB was found to occur throughout the year, including during the winter months, but that it occurred mostly during stationary periods when the truck stopped for driver breaks. A temperature-humidity index was utilised to ascertain what may have triggered the OMB and it was observed that the behaviour typically started when that index reached 72. The study suggests that the welfare of pigs may have been compromised by heat-stress over many of the journeys that were monitored. Keywords: heat-stress; pigs; temperature-humidity index; transport stress},
	issn = {1176-5283},
	author = {Dobinson SSA and Hickford JGH}
}
@conference {3678,
	title = {BRIEF COMMUNICATION: Analysis of the on-farm cost of ovine pleurisy},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {74},
	year = {2014},
	month = {06/2014},
	pages = {62-64},
	address = {Napier},
	abstract = {Pleurisy is the result of an inflammation of the pleura producing fibrous adhesions between the lung and chest wall. In New Zealand (NZ) sheep, it has a substantial impact in terms of lost revenue, animal health and welfare, and in 2006 its cost was estimated at NZ$25.1 million (95\% CI=NZ$10.2{\textendash}48.1; Goodwin-Ray et al. 2008). Little is known about how to diagnose the disease prior to slaughter, although a NZ sheep industry report (Goodwin-Ray 2006) describes a {\textquotedblleft}pneumonia-pleurisy complex{\textquotedblright}, based on the findings of McGowan et al. (1978), Davies (1985) and Pfeffer (1986). Goodwin-Ray (2006) concludes that this complex has a poorly defined aetiology, likely reflecting the observation by McGowan et al. (1978) that some, but not all lambs with enzootic pneumonia, went on to develop pleurisy. In effect there is no evidence of an absolute link between pneumonia and pleurisy},
	issn = {1176-5283},
	author = {Hickford JGH and Hodge S and Bates JR and Hogan AK}
}
@conference {89244,
	title = {Association of the KRT33A (formerly KRT1.2) gene with live-weight and wool characteristics in yearing Perendale sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {73},
	year = {2013},
	month = {Jan},
	pages = {158-164},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {<p>DNA samples from 691 mixed-sex Perendale sheep, born between 1998 and 2001, were typed for variation in the KRT33A gene using polymerasechain reaction - single-strand conformational polymorphism. The sheep were the progeny of two linesselected for either decreased (L), or increased (H) core bulk at yearling shearing, crosses between the lines and back-crosses. Five variants (A{\textendash}E) of KRT33Awere identified with a frequency of 0.07, 0.04, 0.07, 0.35 and 0.47, respectively. The proportion of Adecreased and Bincreased, with a progressive increase incrimp frequency, fibre curvature and core bulk and a progressive decrease infleece weight, staple length and washing yield with each step-wise increase in the proportion of genes derived fromthe H line. An effect of the presence of Aon the measured wool characteristics was found, but was less than the effect with direct selection for core bulk. There was no consistent effect on body growth. While none of the variants of KRT33Awere strongly predictive of variation in core bulk, other genes on Chromosome 11 may be implicated in the differential expression of characteristics associated withcore bulk.</p>
},
	issn = {1176-5283},
	author = {Sumner RMW and Forrest RHJ and Zhou H and Henderson HV and Hickford JGH}
}
@conference {89243,
	title = {Association of variation in the ovine ADRB3 gene with weaning weight and post-weaning growth in New Zealand Suffolk sheep},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {73},
	year = {2013},
	month = {Jan},
	pages = {155-157},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {<p>β3-adrenergic receptors (ADRB3s) are mediators of the lipolytic and thermogenic effects of catecholamine levels in brown and white adipose tissue. Studies have linked variation within the β3-adrenergic receptor gene (ADRB3) to metabolic disease and obesity in humans (NCBI OMIM No. 109691), variation in loin eye muscle area in pigs (Hirose et al. 2009) and with dairy form in cattle (Connor et al. 2006).</p>
},
	issn = {1176-5283},
	author = {Yang G and Forrest RHJ and Zhou H and Fang Q and Hickford JGH}
}
@conference {41883,
	title = {Gene markers for wool fibre traits},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {66},
	year = {2006},
	month = {Jan},
	pages = {139-144},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Napier},
	abstract = {Selective breeding has been used for thousands of years to improve the quality and weight of wool, but surprisingly there is still a large amount of genetic variation present at the loci involved in the {\textquotedblleft}blueprint{\textquotedblright} for wool synthesis. This genetic heterogeneity results in considerable variation within, and between individual fleeces. This has both positive and negative implications. Where a wool processor requires uniformity in raw stock, both to gain efficiency in processing and to make a product to specification, it has a negative effect. Where specific traits convey unique properties it opens up opportunities for differentiated products. Markers for genes or knowledge of individual gene effects may be useful for identifying sheep with desirable wool traits that are difficult or expensive to measure under field conditions. The discovery of genetic variation in valuable fibre traits could allow the development of gene-marker tests which would assist breeding for more consistent wool.},
	issn = {1176-5283},
	author = {Abbott JKR and Hickford JGH and Sumner RMW}
}
@conference {41565,
	title = {Sire-line differences in lamb losses from starvation exposure},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {65},
	year = {2005},
	month = {Jan},
	pages = {186-190},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {  Sire-line differences in neonatal lamb mortality due to starvation-exposure (diagnosed using basic {\textquoteleft}on farm{\textquoteright}  observations) were observed in five trials (1390 lambs in 15 sire-groups).  After correcting for variations in lamb birth  weight and in the cold challenge experienced by each lamb using logistic regression, sire-line differences in lamb  mortality due to starvation-exposure were detected in flocks where the cold challenge and the number of progeny in  each sire line was sufficient (P < 0.05). Although sire-line differences in lamb mortality due to starvation-exposure were  detected independent of birth weight, the analyses revealed that birth weight is still the largest influence upon lamb  mortality due to cold exposure (P < 0.05). These results confirm that due to the large and contradictory role that birth  weight has in influencing lamb survival, it is extremely important to record and account for it in any attempt to breed  for enhanced lamb survival. The detection of sire-line differences in lamb mortality due to starvation-exposure  independent of birth weight could provide a basis to select for improving lamb survival, thus raising the efficiency of  lamb production.},
	issn = {1176-5283},
	author = {Gudex BW and Hickford JGH and Frampton CM}
}
@conference {41551,
	title = {A survey of the control and financial impact of footrot in the New Zealand Merino industry},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {65},
	year = {2005},
	month = {Jan},
	pages = {117-122},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = { A survey was sent to 869 Merino farmers in New Zealand in August 2001 seeking information about the  prevalence of footrot, treatment and control measures applied, their related costs, and estimated production losses  attributable to the disease. There were 304 respondents to the survey and they farm approximately 43\% of the Merino  sheep in New Zealand. Footrot was reported to be present  in 59\% of the respondents{\textquoteright} flocks with 6.4\% of the sheep  infected by footrot at the time of surveying. Foot bathing, culling of affected sheep and breeding for footrot resistance in  flocks were the preferred control measures. Footrot treatment was calculated to cost $1.67 per Merino sheep per year  with an additional $1.77 per sheep attributed to losses in animal production. Assuming the respondents are  representative of the New Zealand Merino industry, the total cost of footrot to this industry was estimated to be in excess of $11 million annually.},
	issn = {1176-5283},
	author = {Hickford JGH and Davies S and Zhou H and Gudex BW}
}
@conference {41493,
	title = {Relationship between intramammary infection and teat characteristics},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {64},
	year = {2004},
	month = {Jan},
	pages = {147-149},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Hamilton},
	abstract = {The relationship between teat characteristics and intramammary infection (IMI) was investigated in 111 cows. These cows were scored visually on teat shape, teat-end shape and teat pigmentation. Subsequently, foremilk quarter samples were collected weekly for 14 weeks from calving to assess bacterial presence and somatic cell count (SCC). Teat shape and teat-end shape were combined and termed teat type. The distribution of teat type was cylindrical- round (34\%), funnel-round (21\%), cylindrical-flat (16\%) and bottle-round (9\%). Approximately 44\% of teats were fully pigmented (black/brown) while 25\% of teats were pigmented over less than 20\% of the surface area. The frequency of quarters that never became infected during the trial period was 78.4\% and the mean SCC was 69,000 cells mL-1. Among the infected quarters, the most frequently isolated pathogens were Corynebacterium bovis (45\%), coagulase negative staphylococci (CNS) (43\%) and Streptococcus uberis (6\%). Analyses showed no associations between teat characteristics and quarters not becoming infected, or between teat characteristics and bacterial pathogens in infected quarters. },
	issn = {1176-5283},
	author = {Lopez-Benavides MG and Williamson JH and Walters JB and Hickford JGH}
}
@conference {41263,
	title = {The search for quantitative trait loci affecting wool colour},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {61},
	year = {2001},
	month = {Jan},
	pages = {104-108},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	address = {Christchurch},
	abstract = {Farmers have been attempting to breed whiter wool for some time using quantitative and subjective genetic selection based on phenotypic traits. The improvement of wool colour using this form of selection has achieved limited success. The advent of DNA marker maps has introduced the possibility of more directly relating phenotypic and genetic variation. Work presented here has identified a total of ten potential quantitative trait loci (QTL) that are significant at the suggestive level, and one additional QTL that approached this significance threshold that influence wool colour. There have been five putative QTL identified for base colour or challenge colour brightness. Two QTL affecting challenge colour yellowness was identified, while three QTL identified were linked to predictive colour variation. An additional QTL that affected predictive colour has also been mapped to a non-specific location on chromosome 24. Several further key areas of research need to be addressed before the DNA markers can be developed for use in the improvement of wool colour. },
	issn = {1176-5283},
	author = {McKenzie GW and Maher AP and Dodds KG and Beattie AE and Henry HM and Hickford JGH and Montgomery GW}
}
@conference {40965,
	title = {A candidate gene approach to animal quality traits.},
	booktitle = {Proceedings of the New Zealand Society of Animal Production},
	volume = {57},
	year = {1997},
	month = {Jan},
	pages = {294-296},
	publisher = {New Zealand Society of Animal Production},
	organization = {New Zealand Society of Animal Production},
	abstract = {A variety of animal quality traits, particularly those associated with meat and wool production and disease resistance, have been the subject of sophisticated genetic analyses. Investigation of the biochemistry and physiology underlying disease or production traits has implicated particular proteins and hence genes as "candidates" for having major phenotypic effects. This makes the candidate gene approach a useful complement to animal genome mapping of markers and QTLs. We have applied the candidate gene approach for the sheep quality traits of meat tenderness and footrot resistance. A three allele system detected by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) has been observed for the ovine calpastatin gene. Calpastatin is the specific inhibitor of the ubiquitous calcium-dependent proteases u-calpain and m-calpain. There is very strong population genetic and protein assay data in cattle to inversely correlate post-mortem calpastatin levels with meat tenderness. Assay of post-mortem calpastatin levels in aging lamb confirms an important regulatory role for calpastatin in sheep meat aging. Data sets from preliminary experiments testing the association of the three allele ovine calpastatin system with meat tenderness values and other meat quality characteristics show significantly different fillet tenderness, early post-mortem calpastatin and u-calpain levels between ewes with different calpastatin genotypes. The early post-mortem calpastatin levels and the longissimus dorsi pH at 24 hr post-mortem of sheep representing two different genotypes was also significantly different. The major histocompatibility (MHC) proteins of vertebrates have a role in presenting peptide fragments from pathogenic organisms to the systemic immune system. It is hypothesised that a component of resistance in sheep to footrot is based on an effective systemic immune response and hence controlled by MHC presentation. Sixteen alleles have been identified at the ovine MHC class II DQA2 locus and 8 at the DQA1 locus. A significant (p=0.001) association between footrot status and DQA2 genotype was observed in a halfsib family challenged with the disease under standardised field conditions. },
	issn = {1176-5283},
	author = {Palmer BR and Hickford JGH and Bickerstaffe R}
}
