EMU DSpace – Eesti Maaülikooli digitaalarhiiv
Digitaalarhiiv EMU DSpace kogub, säilitab ja loob ligipääsu Eesti Maaülikooli liikmeskonna poolt loodud või Eesti Maaülikooli vastutusvaldkondadega seotud teadustöödele toetamaks maaülikooli konkurentsivõimet ja teadmistepõhist ühiskonna arengut. Digitaalarhiivi haldab Eesti Maaülikooli raamatukogu.
Valdkonnad DSpace's
Valige valdkond, et selle kogusid sirvida.
- Institute of Forestry and Engineering (MMI)
- Institute of Agricultural and Environmental Sciences (PKI)
- Institute of Veterinary Medicine and Animal Sciences (VLI)
- Publications
- Units
Hiljutised sisestused
Comparative welfare evaluation of sheep production systems
(Estonian University of Life Sciences, 2024) Marcone, Giovanni; Arney, David (advisor); Piirsalu, Peep (advisor); Institute of Veterinary Medicine and Animal Sciences; Norring, Marianna (opponent)
The welfare of animals in livestock production is of importance for the animals, the general public and the sustainability of animal agriculture. Ways of assessing welfare for sheep have been developed, but those available are complex, time-consuming and may not be appropriate for the different ways of keeping sheep, different sheep breeds and different climatic conditions. This doctoral thesis examines some welfare problems of sheep farming, including issues related to weather conditions, and devises and tests a simplified welfare evaluation system for sheep that is reliable, easy-to use and is focussed on actual problems. Findings include: Sheep prefer to be outside even in the winter, and even in the cool winters of Estonia, so we should allow sheep to have access to the outdoors, even in winter. In the summer, even in the relatively cool summers of northern Europe, sheep can suffer from heat stress. If sheep are at pasture during warm days they will use shade if it is available, and if they do not have access to shade they are more likely to suffer from the heat. So we should ensure that sheep have access to shade while at pasture. Sheep panting score was used to assess heat stress. This is a simple measure to observe and could be included in sheep welfare assessment protocols. The importance of different welfare indicators for sheep of different interest groups was investigated. In brief, farmers thought that body condition (too thin sheep) was the most important welfare indicator, whereas the general public thought that lameness was the most important. Female respondents thought that welfare issues were more significant than male respondents. A simplified protocol to assess the welfare of sheep was developed, using inputs from welfare scientists and from farmers themselves. This was demonstrated to be practical and easy to use. This could be used by welfare assessors but also by farmers to easily check the welfare of their own sheep themselves.
Response on light interception and radiation use efficiency of selected winter cereals at optimum N fertilizers : [Retracted]
(Estonian University of Life Sciences, 2018) Biabani, A.; Etesam, M.; Rahemi Karizaki, A.; Gholizadeh, A.; Sabouri, H.
Audoktor Marian Kazda
(Eesti Maaülikool, 2024) Eesti Maaülikool
Ulmi Ülikooli emeriitprofessor Marian Kazda nimetati Eesti Maaülikooli audoktoriks 23. mail 2024.
The effect of different harvesting methods on carbon cycling and productivity of forest ecosystems
(Estonian University of Life Sciences, 2024) Uri, Marek; Uri, Veiko (advisor); Varik, Mats (advisor); Institute of Forestry and Engineering; Palviainen, Marjo (opponent)
The forests of the northern hemisphere are the important natural carbon (C) sinks in terrestrial ecosystems, however, the C sequestration capacity of stands can be significantly affected by different harvesting methods. Clear-cutting is the prevailing forest management method in Northern Europe, and its effect on the C cycle of the site is appreciable. Clear-cuts act as C sources and quantification of the amount of C loss, as well as evaluation of the post harvesting recovery dynamics of C balance are crucial issues. The annual net ecosystem production (NEP) of mesotrophic pine and fertile silver birch clear-cut areas varied between 1.7-1.9 and 0.4-0.5 t C ha-1 yr-1, respectively. The ecosystem turned into a C sink at a stand age of seven years for Scots pine and six years for silver birch. The C payback period, which indicates the time lag for replenishing the cumulative C loss before C balancing, was estimated at age of 12 and 10 years for Scots pine and silver birch, respectively.
Shelterwood cutting (SWC) allows avoidance of drastic changes in the landscape and is recognized as an alternative method to clear-cutting. However, the impact of SWC on C stocks and C fluxes of the forest ecosystem is still a relatively poorly studied issue. In the current study, one of the studied stands turned into a C source after SWC, while the other remained a weak C sink (-1.3 and 0.6 t C ha-1 yr-1, respectively). Although in the short term, SWC demonstrated a certain advantage over clear-cut in terms of the C cycle, then for relevant evaluation, the whole rotation cycle should be considered. The net ecosystem exchange for the post-SWC area, measured by the eddy covariance technique in the first post-harvesting year, showed a larger C sink than that estimated by the budgeting method. The above divergence was largely induced by the cumulative uncertainty of NEP, which is inherent in the bottom-up budgeting approach.
In Estonia, the more extensive implementation of selective cuttings and the principles of continuous cover forest management in forestry are increasingly highlighted. Based on the results of experimental transitional selective cuttings in mature mesotrophic pine stands it would be possible to maintain the old stand over a longer period in case a considerable amount of timber is removed by repeated cuttings. The results of the simulated further growth dynamics of post-harvested stands showed a considerably lower total wood production over the following 40 years compared to the production of forests formed after clear-cut.
Proteome profile of bovine uterine extracellular vesicles during the oestrous cycle and in endometritis
(Estonian University of Life Sciences, 2024) Piibor, Johanna; Valdmann, Andres (advisor); Institute of Veterinary Medicine and Animal Sciences; Forde, Niamh (opponent)
Uterine fluid (UF) provides a microenvironment for the growth and survival of pre-implantation embryos and facilitates embryo-maternal communication. While effective communication and nurturing of pre-implantation embryos via UF contribute to improved embryonic implantation and development, the disrupted or suboptimal conditions can lead to implantation failure and pregnancy loss. Recent studies have revealed the role of extracellular vesicles (EVs) in cell-to-cell communication. EVs are lipid membrane-bound nanoparticles containing a range of biomolecules, which when transferred from one cell to another can influence the state of another cell. Several postpartum reproductive inflammatory diseases have been documented, with endometritis emerging as the primary long-lasting fertility-affecting ailment. Postpartum endometritis in dairy cattle refers to inflammation of the endometrium that occurs three weeks or more after parturition, exhibiting no systemic signs of illness. We studied the bovine UF-EV profiles in healthy cows and those with endometritis. We found that UF-EV concentration, size and proteomic profile show clear differences between follicular and luteal phases in naturally cyclic, the days of the oestrous cycle in synchronized cows and cows with clinical (CLE) and subclinical endometritis (SE). Moreover, supplementing UF-EVs from cows with CLE or SE to embryo cultures in vitro had determinantal impact on blastocyst rates and/or quality compared to UF-EVs from healthy cows. Our study identified HTRA1 as potential biomarker for SE. Future investigations building upon the insights gained from this thesis could potentially address challenges with diagnosing SE and improve in vitro fertilization technologies (e.g., increase blastocyst rates, improve embryo quality) making it more feasible to use in farms.