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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 Feed not food : alternative feedstuffs for growing-finishing pigs : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Manawatu, New Zealand(Massey University, 2023) Nguyen, ThanhConventional diets used in the swine production sector, which rely heavily on soybean meal (SBM) and cereal grains, do not align with sustainable development goals. Hence, exploring alternative feedstuffs that are inexpensive, environmentally friendly, and do not compete with human food sources is essential to meeting future expectations around sustainability. As pigs are omnivores, they can efficiently convert many types of feed into a nutritious protein source for human consumption. Therefore, research and development in alternative feedstuffs for pigs are ongoing, and farmers are encouraged to adopt these options to enhance the sustainability of their operations. However, incorporating alternative feedstuffs in the diets of grower-finisher pigs requires proper risk management as they can contain high levels of insoluble fibre and other anti-nutritional factors that may affect pig growth performance, pork quality, and welfare. This thesis aimed to investigate alternative ingredients for inclusion in growing-finishing pig diets. The first experiment (Chapter 3) examined the effect of replacing barley, SBM and soybean oil with dried distiller’s grains with solubles, canola meal, wheat middlings and tallow on pig growth performance and meat quality. There were no negative effects of the alternative diet on overall pig growth or carcass performance, however, skatole levels of backfat were significantly lower in pigs fed the alternative diet. The second experiment (Chapter 4) investigated the effect of lucerne as an ingredient in grower-finisher diets and as manipulable enrichment material on pig growth performance and behaviour. Feeding the lucerne diet reduced average daily feed intake, live weight gain, feed intake per feeder visit, and feeding rate, but increased feed efficiency. Despite these effects, overall performance was not significantly different between treatments when considering feed conversion ratio, final slaughter weight, dressing out percentage and backfat thickness. The third experiment (Chapter 5) investigated the effect of replacing SBM with Poultry by-product meal (PBM) in growing-finishing pig diets on growth performance, carcass yield and meat quality. Four experimental diets were formulated, in which SBM was replaced with PBM at the increasing level of 0%, 33%, 77% and 100%. The diets were then fed to growing-finishing pigs. The results clearly demonstrate that PBM can be used as the primary protein source in pig diets without compromising the performance of growing pigs, as long as the diets are properly formulated to meet their nutritional requirements. A meta-analysis (Chapter 6) was conducted to assess the impact of substituting SBM with alternative oilseed meal, including canola meal, camelina meal, cottonseed meal, sunflower meal and rapeseed meal, on the performance of growing-finishing pigs. The findings indicate that this replacement adversely affected pig's daily weight gain while maintaining daily feed intake, resulting in an increased feed conversion ratio for both growers and finishers. Furthermore, the use of alternative oilseed meals led to reducing carcass and loin yield, although there was no significant impact on meat quality. However, the heterogeneities of the analysis for most parameters were substantial, possibly due to the variation in the nutritive value of the alternative oilseed meal. Overall, the results showed that substituting conventional feed ingredients with alternative feedstuffs had no or minor impacts on pig growth performance and meat quality. Additionally, several benefits of using alternative feedstuffs ingredients in growing pig diets were identified: reducing skatole in pork from entire males and improving feed conversion efficiency. The present research indicates that using alternative feedstuffs can be a viable option for pig feed, with possible benefits for pig production, meat quality and animal welfare. The field of alternative feedstuffs for pigs has much to explore, with numerous undiscovered options, such as legumes, brassicas, insects, and by-products, which can offer valuable nutrients and support sustainable pork production. These alternative feedstuffs may have multiple benefits, such as improved gut utilization, support for pig health, lower production costs, and reduced environmental impact. Furthermore, using feed additives to enhance the utilization of low-nutritive-value alternative feedstuffs is a viable option. As such, further research should focus on integrating these feedstuffs into pig diets while promoting sustainable development.Item Ruminants' milk in early postnatal brain development in a pig model of the human infant : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science at Massey University, Manawatū, New Zealand(Massey University, 2023) Jena, AnkitaGiven the rapid brain development in the early postnatal period and its sensitivity towards changes in the external environment like nutrition, this period is of utmost importance for determining later life health and well-being. Emerging evidence suggests a link between the triad of early life nutrition, the gut and brain axis and its potential for optimising or retrograding early postnatal brain development. In this context, human breast milk has been most studied. However, whether the development of the brain is responsive towards milk from ruminant species used to make milk formula via modulating gut-derived molecules has not been well understood. The aim, therefore, of the thesis was to evaluate the effects of milk from bovine, caprine and ovine species on circulatory blood plasma metabolites, brain tissue metabolites and brain tissue gene expression in piglets and establish associations between changes in plasma metabolite profile with neurochemical and molecular features of the brain. The hypothesis was that metabolites in the peripheral circulation would differ between different ruminant milk consumption, influencing brain metabolite and gene expression. Liquid chromatography-mass spectrometry-based metabolomics was used to profile the plasma, hippocampal, prefrontal cortex, and striatal tissue metabolite relative abundances. NanoString technology was used to evaluate the expression of genes associated with neuro- and cognitive development in the hippocampus, prefrontal cortex, and striatum tissue samples. Multi-omics data integration was used to explore the correlation between plasma and brain lipid profiles. The results showed that the relative intensity of plasma metabolites differed between bovine, caprine and ovine milk treatments, and lipid metabolites were the predominant features. The bovine group had a higher relative intensity of plasma lipids (e.g., saturated triglycerides, phosphatidylcholine, sphingomyelin) than the ovine and caprine milk groups, except for unsaturated triglycerides, which had a higher intensity in the ovine milk group. Metabolite profiling of brain regions indicated that the relative intensity of lipid metabolites, mainly phospholipids, changed in response to different milk treatments. Further analysis showed that in the striatum and hippocampus, the relative intensity of phospholipids in the bovine milk group was higher than in the ovine and caprine milk groups. In contrast, the relative intensity of phospholipids in the prefrontal cortex was higher in the ovine milk group than in the other milk groups. Gene expression profiling showed that the expression of genes in the striatum and hippocampus associated with neurotransmission differed between milk treatments. Both increased and decreased gene expressions were observed in response to ovine milk treatment, whereas a similar gene expression pattern was observed between the caprine and ovine milk treatments. No effect of milk treatments was observed on the prefrontal cortex gene expressions. Striatal and hippocampal lipid relative intensities showed a positive association with that of plasma lipids and the prefrontal cortex showed negative associations. Thus, this PhD research findings suggest that consuming different ruminant milk can impact early postnatal brain development by influencing the peripheral circulatory metabolites in piglets as a model of human infantsItem Aspects of fruit growth and rootstock/scion influence on field performance in kiwifruit (Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. deliciosa) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Horticultural Science at Massey University(Massey University, 1994) Cruz, Castillo Juan GuillermoThe influence of nine Actinidia deliciosa (A. Chev.) C.F. Liang et A.R. Ferguson var. de!iciosa rootstocks and four 'Hayward' strains on the growth and cropping performance of kiwifruit vines four, five, and six years after grafting was determined. Multivariate analysis of variance on phenotypic data was an effective technique to distinguish main effects of rootstock and scion and the interactions between the two. Canonical Variate Analysis was particularly useful for distinguishing between root systems, 'Hayward' selections and their interaction on the basis of field performance. This statistical technique was highly effective in summarizing the complex relationships of the data and provided a useful method of reducing the dimensionality of the problem. A rootstock effect on plants topworked on root system 4 (male) was characterised by high field performance, as expressed by high floral bud burst and high yield of large size fruit in each of three seasons. Own rooted vines had the highest field performance in one season. Own rooted 'Hayward' B strain had a large trunk diameter and high yield in comparison to the other three own rooted 'Haywards', in two seasons. In contrast, when strain 'B' was topworked across eight root systems the vines produced a low yield of small fruit in two seasons. 'Hayward' A as a scion achieved the best field performance in yield and fruit sizing across eight root systems in two seasons. Root system and scion interactions were characterised by differences in 'Hayward' selection effects on individual root systems, and root system effects on individual 'Hayward' selections. In particular scion performance on root system 9 differed significantly, as did the effect of rootstock on the scion selection 'Hayward' D. Fruit from some vines had a significant increase in percentage of soluble solids and fruit firmness at harvest, and during storage. Scion effects on percentage of soluble solids present at harvest were lost after fifteen weeks of cold storage. Conversely, in some cases, significant interaction between rootstock and scions on that variate were found only after a period of fruit storage. Rapid fruit softening during storage occurred in some rootstock scion combinations, particularly 'Hayward' Con its own roots and three of the eight rootstocks. The effects of early summer partial defoliation on fruit size, return bloom, and carbohydrate content of 'Hayward' kiwifruit vines were studied. An arbitrary distinction was made between shoots arising from the 'replacement cane zone' (RCZ), the wide horizontal area between the T-bar support wires, and the fruiting zone (FZ), comprising all growth arising outside the T-bar support wires. A 75 % defoliation of new shoots in the RCZ significantly reduced mean fruit size 13 and 7 g, in the RCZ and FZ, respectively, and starch content of the shoots as determined in March. The treatments did not significantly alter the root starch content over several dates sampled. The return bloom of the vines was significantly reduced by 50 and 75 % defoliation. Pre-anthesis factors and early fruit growth were important in determining final fruit size. Ovaries from early opening flowers had significantly greater fresh weight than late ovaries. Cell number and cell size in the inner and outer pericarp of the ovary at anthesis were similar for early and late opening flowers but core cell number was significantly higher for ovaries from early flowers. At commercial harvest, the cell number in the outer pericarp of fruit from early flowers was greater than fruit from late flowers. When treated with the synthetic cytokinin CPPU (N-(2-chloro-4-pyridil)-N-phenylurea), fruit from early flowers achieved a larger fruit size than fruit from late flowers. Fruit weight response to the synthetic cytokinin CPPU was enhanced when applied in combination with GA₃ (gibberellic acid) + 2,4-D (2,4-dichlorophenoxyacetic acid) in three seasons. In treated 'Hayward' fruit, the relative thickness of the outer pericarp was increased, and the inner pericarp decreased. Low and high seeded fruit treated with the hormone mixture had mean fresh weights of 102 and 136 g, respectively, compared with 47 and 90 g in untreated fruit. In kiwifruit inner pericarp cultured in vitro there was no callus growth in the absence of hormones, even when seed were present. A mix of 2,4-D + GA₃ + BAP (6-benzylaminopurine) stimulated callus growth. In the presence of 2,4-D + GA₃ , seeds or BAP increased fruit callus growth and reduced the phytotoxicity effect of abscisic acid (ABA). The uptake of ¹⁴C-CPPU and ¹⁴C-CPPU + 2,4-D + GA₃ by 'Hayward' kiwifruit, and the distribution of radioactive label in fruit tissues was examined. After 21 days the recovery of radioactivity was significantly greater from fruit treated with mixture compounds to CPPU alone. At commercial harvest radio-active metabolites of CPPU were on average 6.2 and 4.8 ppb (fresh weight basis) for soluble and insoluble acetone fractions, respectively. Of this activity, 90 % was present on the skin, and 10 % in the flesh.Item Growth studies with lettuce (Lactuca sativa L) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science in Plant Science at Massey University(Massey University, 1974) Lee, Kong KianIn a sand culture experiment carried out in a heated glasshouse, the effect of five levels of P (ranging from 7.75 p.p.m. - 124 p.p.m. on the growth of two cultivars of lettuce was examined. Samples were taken at weekly intervals for ten weeks and growth analysis, and chemical analysis of the whole plant were carried out for total N, P and K from the samples. Significant differences between cultivars were found for net assimilation rate and leaf area ratio, with a slightly higher relative growth rate in young 'Cobham Green' plants. 'Cobham Green' had a greater leaf area ratio but smaller net assimilation rate than 'Webb's Wonderful' . The higher relative growth rate of Cobham Green at the early stages of growth was mainly due to its higher leaf area ratio, but net assimilation rate became an important component during later growth stages, possibly as a result of mutual shading. Within each cultivar, however, the variation in relative growth rate was based on net assimilation rate rather than in leaf area ratio. Both dry weight and the percentage of total P increased with increase in P supply. The percentages of total N and K decreased towards the market maturity but no general trend was observed in the percentage of total P.Item The effect of plant density, cultivar and season on the growth and development of broccoli : a thesis presented in partial fulfilment of the requirements for the degree of Master in Horticultural Science (Vegetable Production) at Massey University(Massey University, 1995) Pinera, Danilo RTwo field trials (summer and winter) were conducted at the Plant Growth Unit (PGU) to investigate the effects of density and season of planting on different cultivars of broccoli. Different aspects of growth and development were studied including dry matter accumulation, leaf production, curd initiation and curd maturity. Polynomial regression equations were fitted to the primary data and resulted in typical growth curves from which growth analysis parameters were derived. The season of planting significantly effected the developmental stages of the crop. RGR calculated according to the functional approach declined linearly with time in both winter and summer trial. It was initially highest in the summer trial but declined much faster than in winter trial. One of the components of RGR, namely LAR also showed the reduction over time, in both summer and winter plantings. The other component, NAR decline with time in summer, but showed slight increase over time in the winter trial. LAR was consistently lower during the summer trial compared with the winter trial. This consistent reduction is associated mainly with a lower specific leaf weight (SLW) because plants have thicker leaves which may absorb more radiation and therefore be more efficient in dry matter production. Differences in growth between seasons can be explained primarily by differences in accumulated heat units. In this study, it was evident that the number of leaves produced varied with planting season. The higher the temperature regime the more leaves produced hence, leaf count per plant was slightly higher in the summer than during the winter season. The time of head initiation were affected by planting density for both season. In the summer planting, widely spaced plants had higher leaf areas, number of leaves produced and curd yield but in the winter planting showed no significant differences in the number of leaves produced and the curd weight per plant between densities. The final number of leaves at initiation time showed variations with season of planting which suggests that leaf number can be useful index for the morphological age of the plant at curd initiation stage. Curd initiation (an important developmental event) was found to be strongly influenced by temperature. The number of days from transplanting to curd initiation was shorter in summer and longer in winter season. Considering a normal time scale, variations in the number of days from planting to curd initiation until maturity for both season was influenced by the two developmental stages of the crop: 1) planting to curd initiation, 2) curd initiation up to maturity. It took almost twice as long period for the plant to initiate curd during winter than during summer and the time from curd initiation to maturity was longest during the winter. The potential of the plants to produce dry matter varied with season. Total dry matter production was considerably lower in the winter crop which strongly suggests that the lower the temperature regime, the lower the potential for dry matter production. The heat unit accumulation necessary to bring the crop to the same stage of maturity varied in such a manner that it was lower when the season was cool, and higher when the season was warm. Total biomass per unit area increased with later harvests in the summer planting. Density influenced the curd and total dry weight per plant only in the summer planting. Varietal differences were found for both season of planting. Cultivar Shogun, with the longer growing period, had the lowest dry weight per plant for both plantings.Item Leaf regrowth stage as a morpho-physiological indicator of Bromus valdivianus and Lolium perenne mixed pasture defoliation in New Zealand grazing system : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Plant Science at Massey University, Manawatū, New Zealand(Massey University, 2022) García Favre, Javier HoracioBromus valdivianus Phill. is a perennial grass species native to the South of Chile. Its better fitness for growing under low water availabilities compared with Lolium perenne L. has been assessed in field and glasshouse studies. However, Bromus valdivianus morpho-physiological attributes, such as root development under field conditions, and competitive ability are likely to manifest differently under contrasting defoliation criteria based on leaf regrowth stage. In addition, Lolium perenne and B. valdivianus growth can be complementary throughout the year under rainfed conditions. Therefore, the objective of the present thesis was to determine defoliation criteria based on leaf regrowth stage of mixed pastures (50/50% L. perenne and B. valdivianus) and consequences for species succession and functional traits development of the species. Four studies were developed in the thesis, two glasshouse and two field studies. The first glasshouse study evaluated the growth response and water-soluble carbohydrate (WSC) accumulation of B. valdivianus at three different defoliation frequencies. The results suggested that B. valdivianus increased herbage mass production and root biomass at low defoliation frequency (i.e., at 3.5–4.0 leaf regrowth stage). This was related to a higher WSC accumulation in the tiller base. In addition, under low soil water availabilities (20–25% of field capacity) WSC increased by ~20%, which indicated a drought resistant strategy of this species. The second study proved the growth enhancement (mainly root length and biomass) of B. valdivianus under competition with L. perenne compared with intraspecific competition when soil water shifted from high to low availabilities. In field studies, B. valdivianus mixed with L. perenne increased ~15% accumulated herbage mass compared to the species monocultures, which supported higher production during dry periods. This was due to the niche complementarity and asynchrony in herbage growth between the species, with B. valdivianus capable to maintain a steady tiller population throughout the year and root biomass accumulation at depth. Whereas L. perenne grew more than B. valdivianus under low level of oxygen in the soil and under optimal growth conditions and presented a higher nutritive value than B. valdivianus during winter, spring and autumn. The latter supports the partial grazing preference for L. perenne shown by sheep during part of the year, as measured in the second field study. This lower nutritive value (less energy) of B. valdivianus monocultures was overcame in the mixture, with a good overall value for high animal production. Regarding the mixture defoliation criterion, it was shown that it can be based on the optimal leaf regrowth stage of either species, as herbage mass production was similar between defoliation frequencies based on optimal leaf regrowth stage of either of the species. However, under defoliation based on optimal leaf regrowth stage of B. valdivianus, root biomass accumulation at depth increased ~45%. Overall, the results of the present thesis evidenced that Bromus valdivianus can successfully grow alongside L. perenne and, therefore, the mixture can increase forage production of New Zealand farming system in the event of climate change.Item Artificial rearing strategies to optimise new-born lamb growth and development : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science at Massey University, Palmerston North, New Zealand(Massey University, 2022) Hitihamy Mudiyanselage, Gayani Priyadarshani HerathA series of artificial lamb rearing experiments was conducted to investigate the effects of milk replacer protein to energy ratio (CP:ME), pellet fibre level and age at weaning on lamb growth and body composition, rumen development and rumen bacterial population. A mechanistic, dynamic, pre-weaned lamb growth and body composition simulation model was also validated using data generated from these experiments. The feeding of milk replacers with a high CP:ME ratio (15.89 g/MJ compared to a traditional industry value of 10.96 g/MJ) and adjustment of replacer CP:ME ratio (16.46 g/MJ to 10.96 g/MJ) to meet the lamb’s changing nutritional requirement as it aged resulted in higher pre-weaning lamb growth rates. Feeding a high CP:ME milk replacer also reduced carcass fat levels. When fed pellets ad libitum, an incrementally adjusted CP:ME milk replacer resulted in similar pre-and post-weaning growth rates as when fed milk replacer with a consistently high CP:ME ratio (12.28 g/MJ). Early milk weaning of lambs at 42 days of age did not impair growth rate to 57 days age but, reduced carcass fat, regardless of pellet fibre level. Early weaning of lambs also improved rumen n-butyric content and feeding low fibre pellets (NDF 116.76 g/kg) increased rumen n-valeric content. Early weaned lambs had increased rumen dorsal wall thickness. Nutrient intake from solid feed positively influenced rumen volatile fatty acid content, while both nutrient intake and rumen volatile fatty acid content positively impacted rumen physical development. The relative abundance of rumen bacteria phyla and genera were altered by weaning age and pellet fibre level, with Firmicutes being more abundant in milk-fed lambs at 57 days of age, while Bacteroidetes were the prominent phylum in early-weaned lambs. Prevotella was the prominent bacteria genus in early-weaned lambs. The most abundant bacteria genus in milk-fed lambs at 57 days of age was Succinovibrio. The existing pre-weaned lamb growth model was found to predict overall lamb growth accurately when utilising data collected in the present studies. However, it was not as accurate for predicting body composition components. In summary, results from thesis will contribute to improving new-born lamb growth and development in artificial rearing systems.Item Mapping of multitemporal rice (Oryza sativa L.) growth stages using remote sensing with multi-sensor and machine learning : a thesis dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Earth Science at Massey University, Manawatū, New Zealand(Massey University, 2022) Ramadhani, FadhlullahRice (Oryza Sativa) plays a pivotal role in food security for Asian countries, especially in Indonesia. Due to the increasing pressure of environmental changes, such as land use and climate, rice cultivation areas need to be monitored regularly and spatially to ensure sustainable rice production. Moreover, timely information of rice growth stages (RGS) can lead to more efficient of inputs distribution from water, seed, fertilizer, and pesticide. One of the efficient solutions for regularly mapping the rice crop is using Earth observation satellites. Moreover, the increasing availability of open access satellite images such as Landsat-8, Sentinel-1, and Sentinel-2 provides ample opportunities to map continuous and high-resolution rice growth stages with greater accuracy. The majority of the literature has focused on mapping rice area, cropping patterns and relied mainly on the phenology of vegetation. However, the mapping process of RGS was difficult to assess the accuracy, time-consuming, and depended on only one sensor. In this work, we discuss the use of machine learning algorithms (MLA) for mapping paddy RGS with multiple remote sensing data in near-real-time. The study area was Java Island, which is the primary rice producer in Indonesia. This study has investigated: (1) the mapping of RGS using Landsat-8 imagery and different MLAs, and their rigorous performance was evaluated by conducting a multitemporal analysis; (2) the temporal consistency of predicting RGS using Sentinel-2, MOD13Q1, and Sentinel-1 data; (3) evaluating the correlation of local statistics data and paddy RGS using Sentinel-2, PROBA-V, and Sentinel-1 with MLAs. The ground truth datasets were collected from multi-year web camera data (2014-2016) and three months of the field campaign in different regions of Java (2018). The study considered the RGS in the analysis to be vegetative, reproductive, ripening, bare land, and flooding, and MLAs such as support vector machines (SVMs), random forest (RF), and artificial neural network (ANN) were used. The temporal consistency matrix was used to compare the classification maps within three sensor datasets (Landsat-8 OLI, Sentinel-2, and Sentinel-2, MOD13Q1, Sentinel-1) and in four periods (5, 10, 15, 16 days). Moreover, the result of the RGS map was also compared with monthly data from local statistics within each sub-district using cross-correlation analysis. The result from the analysis shows that SVM with a radial base function outperformed the RF and ANN and proved to be a robust method for small-size datasets (< 1,000 points). Compared to Sentinel-2, Landsat-8 OLI gives less accuracy due to the lack of a red-edge band and larger pixel size (30 x 30 m). Integration of Sentinel-2, MOD13Q1, and Sentinel-1 improved the classification performance and increased the temporal availability of cloud-free maps. The integration of PROBA-V and Sentinel-1 improved the classification accuracy from the Landsat-8 result, consistent with the monthly rice planting area statistics at the sub-district level. The western area of Java has the highest accuracy and consistency since the cropping pattern only relied on rice cultivation. In contrast, less accuracy was noticed in the eastern area because of upland rice cultivation due to limited irrigation facilities and mixed cropping. In addition, the cultivation of shallots to the north of Nganjuk Regency interferes with the model predictions because the cultivation of shallots resembles the vegetative phase due to the water banks. One future research idea is the auto-detection of the cropping index in the complex landscape to be able to use it for mapping RGS on a global scale. Detection of the rice area and RGS using Google Earth Engine (GEE) can be an action plan to disseminate the information quickly on a planetary scale. Our results show that the multitemporal Sentinel-1 combined with RF can detect rice areas with high accuracy (>91%). Similarly, accurate RGS maps can be detected by integrating multiple remote sensing (Sentinel-2, Landsat-8 OLI, and MOD13Q1) data with acceptable accuracy (76.4%), with high temporal frequency and lower cloud interference (every 16 days). Overall, this study shows that remote sensing combined with the machine learning methodology can deliver information on RGS in a timely fashion, which is easy to scale up and consistent both in time and space and matches the local statistics. This thesis is also in line with the existing rice monitoring projects such as Crop Monitor, Crop Watch, AMIS, and Sen4Agri to support disseminating information over a large area. To sum up, the proposed workflow and detailed map provide a more accurate method and information in near real-time for stakeholders, such as governmental agencies against the existing mapping method. This method can be introduced to provide accurate information to rice farmers promptly with sufficient inputs such as irrigation, seeds, and fertilisers for ensuring national food security from the shifting planting time due to climate change.Item Effect of heavier live weight of ewe lambs at breeding on reproductive performance, mammary gland development and subsequent live weight : 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, 2021) Haslin, EmmanuelleBreeding ewe lambs at seven to eight months of age can increase farm profitability and ewe lifetime performance. In New Zealand, 30 to 40% of ewe lambs are bred each year with a minimum recommended pre-breeding live weight of 40 kg. Ewe lamb reproductive performance increases with breeding live weight, therefore, some farmers aim to breed ewe lambs heavier than 40 kg. Increasing ewe-lamb growth rates prior to puberty, to achieve a heavier breeding live weight could, however, impair ewe lamb mammary gland development and lactational performance. Currently, little is known about the impact of breeding heavier ewe lambs on their subsequent performance, live weight, and efficiency. The aim of this thesis was to investigate the effect of breeding heavier ewe lambs on their reproductive performance, mammary gland development and live weight over their first three breeding seasons. Ewe lambs were managed from weaning to breeding and achieved an average live weight of 47.9 ± 0.38 or 44.9 ± 0.49 kg at breeding. A growth rate of 150 g/d prior to the first breeding did not affect ewe lamb mammary gland development to the weaning of their second litter, as measured using ultrasonography. Positive relationships were found between ewe lamb mammary ultrasound measures at one year of age and the growth of their progeny to weaning. The associations between ultrasound measurements and growth of the progeny indicate that ultrasound scanning has the potential to be used as a selection technique for heavier lamb live weight at weaning. Although the live weight difference between treatments was limited to three kilograms, compared with lighter ewes, heavier ewe lambs at their first breeding showed greater fertility rate, litter size and lambing percentage but did not differ in the second and third breeding seasons. Over the first three breeding seasons, heavier ewe lambs had greater lamb production than their lighter counterparts. Ewe lamb live weight treatment had no effect on progeny performance to weaning, nor ewe efficiency over the three-year period. A positive association was found between ewe lamb breeding live weight and their mature live weight at 39 months of age. Farmers should aim to breed their ewe lambs at heavier live weights to maximise their reproductive performance as a ewe lamb and, if well managed, they can achieve increased ewe performance over the first three breeding seasons, although there would be no impact on efficiency. Before firm recommendations can be made to farmers, lifetime performance and longevity of the heavier ewe lambs at breeding needs to be examined.