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Item Genetic and phenotypic relationships between ewe reproductive performance and wool and growth traits in Uruguayan Ultrafine Merino sheep.(Oxford University Press on behalf of the American Society of Animal Science, 2023-03-07) Ramos Z; Garrick DJ; Blair HT; De Barbieri I; Ciappesoni G; Montossi F; Kenyon PRThis study reports genetic parameters for yearling and adult wool and growth traits, and ewe reproductive performance. Data were sourced from an Uruguayan Merino flock involved in a long-term selection program focused on reduced fiber diameter (FD), and increased clean fleece weight (CFW) and live weight (LW). Pedigree and performance data from approximately 5,700 mixed-sex yearling lambs and 2,000 mixed-age ewes born between 1999 and 2019 were analyzed. The number of records ranged from 1,267 to 5,738 for yearling traits, and from 1,931 to 7,079 for ewe productive and reproductive performance. Data on yearling and adult wool traits, LW and body condition score (BCS), yearling eye muscle area (Y_EMA), and fat thickness (Y_FAT), and several reproduction traits were analyzed. The genetic relationships between FD and reproduction traits were not different from zero. Moderate unfavorable genetic correlations were found between adult CFW and ewe lifetime reproduction traits (-0.34 ± 0.08 and -0.33 ± 0.09 for the total number of lambs weaned and total lamb LW at weaning, respectively). There were moderate to strong positive genetic correlations between yearling LW and all reproduction traits other than ewe-rearing ability (-0.08 ± 0.11) and pregnancy rate (0.18 ± 0.08). The genetic correlations between Y_EMA and reproduction traits were positive and ranged from 0.15 to 0.49. Moderate unfavorable genetic correlations were observed between yearling FD and Y_FAT and between adult FD and BCS at mating (0.31 ± 0.12 and 0.23 ± 0.07, respectively). The genetic correlations between adult fleece weight and ewe BCS at different stages of the cycle were negative, but generally not different from zero. This study shows that selection for reduced FD is unlikely to have any effect on reproduction traits. Selection for increased yearling LW and Y_EMA will improve ewe reproductive performance. On the other hand, selection for increased adult CFW will reduce ewe reproductive performance, whereas selection for reduced FD will negatively impact body fat levels. Although unfavorable genetic relationships between wool traits and both FAT and ewe reproductive performance existed, simultaneous improvements in the traits would occur using appropriately designed indexes.Item Genomic Regions Associated with Wool, Growth and Reproduction Traits in Uruguayan Merino Sheep(MDPI (Basel, Switzerland), 2023-01-07) Ramos Z; Garrick DJ; Blair HT; Vera B; Ciappesoni G; Kenyon PRThe aim of this study was to identify genomic regions and genes associated with the fiber diameter (FD), clean fleece weight (CFW), live weight (LW), body condition score (BCS), pregnancy rate (PR) and lambing potential (LP) of Uruguayan Merino sheep. Phenotypic records of approximately 2000 mixed-age ewes were obtained from a Merino nucleus flock. Genome-wide association studies were performed utilizing single-step Bayesian analysis. For wool traits, a total of 35 genomic windows surpassed the significance threshold (PVE ≥ 0.25%). The proportion of the total additive genetic variance explained by those windows was 4.85 and 9.06% for FD and CFW, respectively. There were 42 windows significantly associated with LWM, which collectively explained 43.2% of the additive genetic variance. For BCS, 22 relevant windows accounted for more than 40% of the additive genetic variance, whereas for the reproduction traits, 53 genomic windows (24 and 29 for PR and LP, respectively) reached the suggestive threshold of 0.25% of the PVE. Within the top 10 windows for each trait, we identified several genes showing potential associations with the wool (e.g., IGF-1, TGFB2R, PRKCA), live weight (e.g., CAST, LAP3, MED28, HERC6), body condition score (e.g., CDH10, TMC2, SIRPA, CPXM1) or reproduction traits (e.g., ADCY1, LEPR, GHR, LPAR2) of the mixed-age ewes.Item Reproductive consequences of genetic improvement in clean fleece production in ultrafine Merino ewes : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science, Massey University, Palmerston North, New Zealand(Massey University, 2023) Ramos, ZullyTo date, genetic improvement of Uruguayan Merino sheep has focused on selection for reduced fibre diameter (FD) and increased clean fleece weight (CFW) and live weight (LW). The effects of selection for these traits on ewe productive and reproductive performance have not been studied in Uruguay. The aim of this thesis was to evaluate the impact of a long-term selection program applied in an Uruguayan Merino flock between 1999 and 2018. Phenotypic responses of yearling lambs and adult ewes across 20 years of selection demonstrated that selection strategies applied in the flock resulted in heavier animals that produced heavier and finer fleeces. These phenotypic responses were accompanied by a decrease in body condition score (BCS) at mating, with a small positive change in ewe reproductive performance. Strong positive genetic correlations were found between yearling and adult expressions of FD, CFW, and LW. The genetic relationships between FD and reproduction traits were negligible. There were generally favorable genetic correlations between LW and reproduction traits. The genetic relationships between adult CFW and ewe reproductive performance were unfavorable. Genetic trends indicated that the breeding strategies applied during the study period were effective in improving genetic merit in the traits under selection (FD, CFW, and LW) and caused only marginal genetic changes in BCS at mating and ewe reproductive performance. A total of 13, 22, 42, 22, 24 and 29 genomic regions were significantly associated with FD, CFW, LW at mating, BCS at mating, pregnancy rate, and lambing potential, respectively. The results obtained in this thesis will be used to refine the breeding programmes for Merino sheep in Uruguay in the future.Item A Scholarly Review of Supply Chain Integration within the New Zealand Wool Industry(Operations and Engineering Innovation, Massey University, Manawatu Campus, Palmerston North, 2021-12) Bezuidenhout, Carel N.; Passos de Oliveira, Daniel; Black, Anthony; Murrell, Teresa; Dela Cruz, Chelsea; Vaghela, Bhavin; Kirk, Logan P.; Kathara, Rahul Dilip; Sun, NoahSupply Chain Integration is a vast field of study, and a Google Scholar search will reveal more than 2.7 million publications in this space. This document captures some of the core concepts when the degree of integration of a primary industry supply chain, such as the wool industry, is evaluated. The book was developed after final year students in Massey University’s Logistics and Supply Chain Management Programme conducted an in-depth review as part of a formal assessment. The content of the book is of a scholarly nature and caution should be practiced before any guidelines are implemented. The students studied the literature, reports, newspaper articles and accessed information on the internet. However, the most valuable source of information was through interviews with industry representatives, most noteworthy, an interactive question and answer session with wool exporter, Mr Ryan Cosgrove.Item An investigation of methods for the estimation of medullation in wool samples : a thesis submitted concerning subsection (e), 608, of the animal husbandry section for the degree of Master of Agricultural Science at Massey University, by "Choir"(Massey University, 1937) Choir; McMahon, Patrick ReginaldIn studies of medullation in New Zealand wools the need for an accurate and rapid technique capable of giving a numerical index for the medullation of a sample of wool early became apparent. The matter was complicated by the fact that medullation can only be detected by hand and eye when it exceeds a certain coarseness, and to meet this difficulty the Benzel Test for the detection of hairness was developed by Elphick. (1932) The quantitive application of the test has proved difficult; in discussing the evaluation of the medullation revealed Elphick has pointed out that there are three factors which must be considered. (1) The average diameter of medulla. (2) The percentage of fibres medullated. (3) The average distance down the fibres which medullation extends. In order to arrive at an empirical index be estimated by eye the average percentage of fibres medullated over the staple, and weighted the result arbitrarily according to the type of medulla. [From Introduction]Item A study of some wool-disintegrating bacteria, by "Animal" : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science at Massey Agricultural College(Massey University, 1932) Hursthouse, Katrine Fearon; AnimalThe purpose of this thesis is the isolation and study of the bacteria that ret the wool of living sheep in New Zealand, the study of the distribution of wool-retting bacteria and of some of the conditions in which they bring about decay. It is also desired to show what effect; the wool retting bacteria have upon the hoof of sheep - a substance which like wool, consists largely of keratin - and what effect the hoof rotting bacteria have upon wool. [From Purpose and scope of thesis]Item The structure of the wool follicle with special reference to the growth and form of the fibre(Massey University, 1935) Rudall, K . M.n/aItem A New Zealand crossbred wool futures market : thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science(Massey University, 1968) Tier, Terence JohnThe New Zealand wool clip approximates six hundred and sixty million pounds greasy weight, and is made up of over ninety eight per cent crossbred wool 1 In New Zealand this term applies to lustre wool varying in fineness from 36's to 56's irrespective of the breed or cross of the sheep. Growers may sell their wool by public auction in New Zealand, by private treaty to an individual buyer on their farm, or by auction in the London market. Most wool is sold at auction with only about twelve per cent being sold privately. Auction sales are held in eight selling centres: Auckland, Napier, Wanganui, Wellington, Christchurch, Timaru, Dunedin and Invercargill. [From Introduction]Item The assessment of natural variation in felting and shrinkage in wool from two flocks : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science in Animal Science at Massey University(Massey University, 1997) Kenyon, Paul RichardFelting of wool is unwanted in raw wool scouring, wet treatments of most yarns and in the finished garment. It is desirable in some other uses and essential in the felt industries. The accepted method of testing loose wool felting is the Aachen felting test but it is laborious and relatively expensive. There is no generally accepted method for testing yarn shrinkage. For these trials new techniques using a household tumble dryer were developed for testing loose wool felting and yarn shrinkage. Analysis indicated that successful techniques had been developed for measuring loose wool felting and yarn shrinkage. Results with the loose wool felting technique were found to be highly correlated with those of the Aachen felting method (r = 0.93). The effects of fibre characteristics on both loose wool felting and yarn shrinkage were investigated for straight-bred Romneys and for loose wool felting in ¼Merino ¾Romney (QM) crosses. Loose wool felting was most highly correlated with bulk (r = -0.65 for Romneys and -0.73. for QM's), crimp frequency (r = -0.53 and -0.41 respectively) and lustre (-0.30 and -0.40 respectively). Loose wool bulk (r = -0.25) and greasy fleece weight (r = -0.40) were the most highly correlated to yarn shrinkage. The greasy fleece weight relationship is thought to be environmental in origin. Micron and staple length were found to play only minor roles in loose wool felting and yarn shrinkage. Cotting was found not to be significantly correlated to either loose wool felting or yarn shrinkage. Loose wool feltability was highly correlated (r = 0.65) to yarn shrinkage. A large percentage of yarn shrinkage variation was left unexplained. Part of this is probably due to variation in yarn characteristics and there is a need for a method of producing short-lengths of yarn of constant structure from very small wool samples. The sire effect was significant (P<0.05) and controlled 6.5% of the variation in loose wool felting and 12% in yarn shrinkage. This indicates that selection for either increased or decreased loose wool felting or yarn shrinkage would induce changes in a flock. Further investigation into the effect of scale height is warranted to enhance understanding of variation in felting.Item The revitalisation of a weaving mill : the manufacture of commercially viable textiles through the revitalisation of a weaving mill : integrating traditional weave processes and modern technologies with a focus on practical learning and experience : this exegesis is presented as partial fulfillment of the requirement for the degree of Master of Design, Massey University Wellington, 2015(Massey University, 2015) Webster, HannahThis master's project guides the revitalisation of the Wool Equities' weaving mill in Palmerston North through the use of innovative, creative and industry-led design. It begins with research into the current state of New Zealand's wool industry, value chains, vertical markets and export potential for high quality, luxury woollen products. Global trend research and identification of luxury niche markets provide the international context for the design work. These establish areas of demand for original products that are able to be manufactured viably at the mill, both for interior and apparel fabric exports. Fusion of old and new technologies along with the properties and behaviour of wool go hand-in-hand with weaving knowledge and technical design to form the constructive design basis of this project. Historical and heritage aesthetics are explored through drawings and colour studies at the mill. Motifs are translated into weaving patterns to create unique and original textile pieces that are both contemporary and authentic, with a story behind the design. The project takes an immersive, hands-on approach to learning all the operations at the mill and extending my own knowledge of weaving processes; adapting small-scale samples to commercially viable fabric. The outcome of this project is a range of luxury woollen woven product designs that can be sold to both local and international markets. This will offer long-term commercial opportunities for the mill and promote further development of the business. It will highlight the mill's capabilities to function as a specialty New Zealand weaving company and create innovative new designs. This in turn increases the value of wool and creates a sustainable business practice with a positive future.
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