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Understanding the variations in grazing and rumination behaviours and their associations with production parameters in individual grazing dairy cows : a thesis presented in partial fulfilment of the requirements of the degree of Doctor of Philosophy in Animal Science at Massey University (Manawatū) New Zealand
Full text linkThis thesis aimed to understand: 1) the accuracy of an accelerometer-based sensor to monitor grazing and rumination behaviours in dairy cows; 2) grazing and rumination behaviour patterns and time budgets over 24 hours; 3) potential factors to influence grazing and rumination behaviours; and 4) effects of grazing and rumination behaviours on production parameters. To do this, data including, but not limited to, grazing time, rumination time, measures of cow performance (e.g., milk production and composition, body weight and body condition score), days in milk, and breeding worth index of 162 grazing dairy cows were collected for three consecutive lactation seasons (2018-2021). The analysis was performed on individual study years and results were reported separately for each year.
First, the accuracy of AfiCollar, an accelerometer sensor-based automated device to monitor and record grazing and rumination behaviours in dairy cows was evaluated for a grazing-based system. Spring-calved lactating cows (n = 48) wearing AfiCollar were continuously visually observed for 8 hours (9 am to 5 pm) to quantify minutes per hour spent grazing and rumination. The behaviours being observed were also recorded with the AfiCollar and compared with visual observations using Pearson’s correlation coefficient (r), concordance correlation coefficient (CCC), and linear regression. A strong association was found between the data collected by AfiCollar and the data obtained through visual observation for grazing time (r = 0.91, CCC = 0.71) and rumination time (r = 0.89, CCC = 0.80) with a significant linear relationship between both datasets (p151). A repeated measure design was performed in SAS using PROC MIXED considering the fixed effects of breed and lactation, the random effect of individual cows, and hours of the day as repeated measure to evaluate their effects on hourly patterns and time budgets of grazing, rumination, and idling behaviours. Regardless of the seasonal variations and feed consumed, cows spent most of their daytime grazing (with peaks around dawn and dusk) and most of their nighttime ruminating. Grazing and ruminating patterns were similar between cows from different breeds and lactations, however, JE cows grazed slightly longer than HFR and KC cows; and first-lactation cows grazed slightly longer than mature cows in their later lactations. The onset and cessation of grazing activity by the cows were adjusted according to varying day lengths by season. In addition, a general linear (PROC GLM) mixed model was fitted to test the effects of days in milk, breeding worth, breed, lactation year, individual cow, season, feed, and their interactions on variations in grazing time, rumination time and their relationship. Results indicated that grazing time varied among breeds in Year-2 and Year-3 and among lactation years in Year-1. Rumination time differed between breeds in only Year-3, and it remained the same within lactation years. Grazing time and rumination time varied among different seasons that were related to varying supplementary feeds. Days in milk, breeding worth (except Year-3), and the individual cow had effects (P<0.05) on grazing and rumination times. Grazing time and rumination time had a negative relationship with each other that varied between different seasons but remained the same among different breeds and lactation years. The variance in grazing and rumination times was mostly explained by individual cows (up to 24%), season (up to 12%), and feed (up to 8%). Moreover, results also showed that grazing and rumination times had positive associations with milk yield, fat, protein, and solids. Grazing time had negative and rumination time had positive associations with liveweight, while both grazing time and rumination time had negative associations with body condition score. Grazing time explained up to 1%, and rumination time explained up to 7% of the variance in milk yield, milk fat, protein, and solids.
AfiCollar can reliably monitor grazing and rumination behaviours in dairy cows, however, its accuracy can be improved for a grazing-based system. The animal itself, the season, and the feed are the potential sources of variation in grazing and rumination behaviours and should be considered for management decisions to address the animal’s behavioural requirements. Grazing and rumination behaviours are moderately correlated with performance parameters and explain a small proportion of variance in animal productivity
Figure 2. Two C in First photographic inland record of blacktip reef sharks Carcharhinus melanopterus (Carcharhiniformes: Carcharhinidae) in Indonesian waters
No full textFigure 2. Two C. melanopterus caught by local people on 6 March 2019 in Sentani, Papua province, Indonesia (Photo: Gloria Setyvani Putri).Published as part of Iqbal, Muhammad, Saputra, Rio Firman, Setiawan, Arum & Yustian, Indra, 2019, First photographic inland record of blacktip reef sharks Carcharhinus melanopterus (Carcharhiniformes: Carcharhinidae) in Indonesian waters, pp. 6-10 in Ecologica Montenegrina 24 on page 8, DOI: 10.37828/em.2019.22.14, http://zenodo.org/record/804401
FIGURE 2. A−C. A & B in Oxneriaria pakistanica sp. nov. (Megasporaceae, Pertusariales, Ascomycota) from Darel Valley, Gilgit Baltistan, Pakistan
No full textFIGURE 2. A−C. A & B: Habitus of Oxneriaria pakistanica. (Holotype, LAH37495) C: Apothecia on Thallus D: Ascus with Ascospores F: Cross section of Apothecia. G: AscosporesPublished as part of Iqbal, Muhammad Shahid, Usman, Muhammad, Habib, Kamran & Khalid, Abdul Nasir, 2023, Oxneriaria pakistanica sp. nov. (Megasporaceae, Pertusariales, Ascomycota) from Darel Valley, Gilgit Baltistan, Pakistan, pp. 125-131 in Phytotaxa 579 (2) on page 129, DOI: 10.11646/phytotaxa.579.2.6, http://zenodo.org/record/754314
Hull form optimisation to minimise the total resistance and dynamic responses of small fishing vessels
No full textThis paper presents a novel approach to ship hull form optimisation, aimed at minimising total resistance while simultaneously enhancing the seakeeping performance of a fishing vessel. When conducting optimisation process in minimising resistance, the method employs the minimisation of the y-axis radius of gyration (Ry)by optimising the longitudinal centre of gravity (LCG) and vertical centre of gravity(KG). The influence of altering LCG and KG on Ry, total resistance, and seakeeping is explored. Reducing Ry enhances sea keeping performance, lower added resistance,resulting in a reduced mean total resistance in waves. This finding demonstrates that itis possible to reduce resistance and improve seakeeping performance simultaneously without the need for multi-objective optimisation to balance the two. By employing the method outlined in this paper, seakeeping performance can be enhanced alongside resistance optimisation in a single process. The optimal hull form can reduce root mean square (RMS) vertical acceleration, RMS pitch motion, and added resistance on average by 1.79%, 1.51%, and 6.48%, respectively. In addition, the mean total resistance in waves for the optimised hull form was reduced by up to 4.15% compared to the initial hull form. This method offers a streamlined solution to achieving multiple performance objectives concurrently
Early, non-destructive selection of microspore-derived embryo genotypes in oilseed rape (Brassica napus L.) by molecular markers and oil quality analysis
No full textIn oilseed rape (Brassica napus L.) breeding, microspore culture is frequently applied for the immediate regeneration of homozygous doubled haploid (DH) plants. From the regenerated microspore-derived embryos (MDEs), usually only a smaller subset of around 200 are used for plantlet regeneration and cultivation in the greenhouse until seed harvest, without there being any knowledge about their quality traits and agronomic performance. The random selection of MDEs implies that valuable rare recombinant genotypes may be discarded at an early stage of in vitro culture. We report here on the development of a simple protocol for simultaneously extracting lipids (for oil quality analysis) and the isolation of DNA (for marker-assisted selection) from single cotyledons dissected from MDEs under aseptic conditions, thus keeping the rest of the embryo in vitro for plantlet regeneration. Neither the fatty acid extraction nor the transmethylation with sodium methylate at high pH interfered with subsequent DNA isolation. The feasibility of the protocol was tested using MDEs from a cross segregating for two linked transgenes, fae1 and plsC, affecting the fatty acid composition. Multiplex PCR was performed with specific PCR primers for the plsC gene and with locus-specific primers for a resident single copy fad2 gene. The amplification of the fad2 gene provided a control for the presence of DNA in sufficient quantity and quality, whereas the amplification of the plsC gene showed a 1:1 segregation expected for a single copy transgene in a segregating DH population. The early identification of the 50% MDE genotypes carrying the desired transgenes, along with a high expression of the trait, allows their early selection for plantlet regeneration
Unsteady RANS CFD simulation on the parametric roll of small fishing boat under different loading conditions
No full textFishing boats have unique features that make them prone to changing loading conditions. When the boat leaves the port, the empty fish tank gradually fills up during fishing operations which may result in parametric roll (PR). This dangerous phenomenon that can lead to capsizing. The present study aims to understand better the behaviour of parametric roll in fishing boats and its relation to changing loading conditions. The study considers the effects of displacement and the GM/KM ratio on parametric roll, as well as the longitudinal flare distribution at the waterline. Two assessments to detect the parametric roll occurrence in early stage were carried out by using the level 1 assessment of parametric roll based on the Second Generation of Intact Stability criteria (SGIS) from International maritime Organisation (IMO) and the Susceptibility criteria of Parametric roll from the American Bureau of Shipping (ABS). Then, the CFD method is used to predict the amplitude of the parametric roll phenomenon. The results provide important insights to fishing vessel operators on how to manage loading conditions to maintain stability and avoid hazardous situations. By following the guidelines outlined in this study, fishing boats can operate more safely and efficiently, reducing the risk of accidents and improving the overall sustainability of the fishing industry.</p
Operability analysis of traditional small fishing boats in indonesia with different loading conditions
Full text linkMany ship accidents are experienced by small boats. With a large number of small fishing boats in Indonesia, the risk of potential ship accidents is high. Therefore, an operability analysis must be conducted for various loading conditions to address any safety issues due to severe vessel motion. The net cargo of a fishing boat will change during its operation at sea and then will affect the vessel’s seakeeping characteristics. This study aims to determine the effect of changes in load and their effect on a traditional fishing boat’s operability in Indonesia, considering the ship’s intact stability. In addition, this study also highlights the response of the ship roll motion to prevent stability failure. The stability curve is used to relate ship stability analysis to seakeeping analysis. Percentage operability and Operability Robustness Index are used to assess the root mean square (RMS) roll response and the ship's expected maximum roll motion
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