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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Habitatové preference jelena lesního v Krkonošském národním parku / Habitat preferences of red deer in the Giant Mountains NP

Hazdrová, Kristýna January 2019 (has links)
The thesis deals with the evaluation of habitat preferences of the red deer in the Krkonoše National Park. In the context of Central Europe, the Krkonoše Mountains are an important locality in which many rare and protected ecosystems are located. The current management is trying to restore the species composition of the forest, which was abundant in the past and replaced by atypical spruce species. Red deer (Cervus elaphus), which lives in these forests, has no natural enemy in the Giant Mountains, so it is necessary to control the local population and perform selective management for the purpose of forest protection. For proper management planning it is important to know the life strategies of the red deer: the deer's preffered habitat, physical-geographical characteristics that affect its movement and spatio- temporal use of the area. This information can be obtained through GPS-telemetry collar monitoring. The monitoring campaign in the Giant Mountains was carried out between 2014 and 2018 and the resulting data are used in this work. Information on 71 individuals of red deer are processed and subjected to spatio-temporal analysis, which shows that deer behavior is influenced by both daily and annual cycles. Another aspect influencing its movement is the density and intensity of the use of...
22

Tauriųjų elnių (Cervus elaphus L.) auginimas aptvaruose / Breeding of Red Deers (Cervus elaphus L.) in Enclosures

Gavorka, Vaidotas 21 June 2010 (has links)
Magistro darbe tiriami tauriųjų elnių auginimo aptvaruose ypatumai Lietuvos sąlygomis. Darbo objektas - S.Petraičio privatus elnininkystės ūkis, esantis Joniškio rajone. Darbo tikslas - išaiškinti aptvaruose auginamų tauriųjų elnių augimo ir veisimosi ypatumus. Darbo uždaviniai – nustatyti tauriųjų elnių veisimosi, kūno ir ragų augimo ypatumus, užsikrėtimą ligomis bei parazitais. Išaiškinti ar šėrimo racionas tenkina tauriųjų elnių poreikius. Darbo metodai – vizualinis tauriųjų elnių stebėjimas visais metų laikais, nustatant elgsenos ypatumus. Helmintų tyrimas (helmintoovoskopija) – laboratorijoje tiriami sviežiai surinkti tauriųjų elnių ekskrementai. Šėrimo raciono išaiškinimas, pagal maisto medžiagų kiekius skirtingose pašaro rūšyse ir elnių poreikius nustatomas jo pakankamumas. Rujos, jauniklių vedimo bei įvairių kitų darbų ir operacijų stebėjimas tiesiogiai dalyvaujant jose (haremų tvarkymas, vakcinavimas, ženklinimas (numeravimas), ir kt.). Kūno morfometrijos duomenys surinkti iš jau sumedžiotų elnių. Numestų ragų matavimas pagal CIC sistemą. Darbo rezultatai – intensyviai ūkininkaujant ir esant labai dideliam tauriųjų elnių tankumui susiduriama su labai daug problemų. Joniškio rajone esančiame elnininkystės ūkyje paskutiniais duomenimis yra 800 tauriųjų elnių, kurie gyvena 150 ha senų obelų sodų ir natūralių pievų, t.y. 5,3 individo kiekviename hektare. Esant tokiam žvėrių tankiui ir nevykdant dehelmintizacijos absoliučiai visi jauni elniai, o ypač iki vienerių metų... [toliau žr. visą tekstą] / In the Master’s Thesis the peculiarities of breeding the red deers in enclosures under the conditions of Lithuania are investigated. Work object – private deers’ farm of S.Petraitis in Joniškis region. Work aim – to reveal the peculiarities of growing and breeding of red deers in the enclosures. Work objectives – to ascertain the peculiarities of breeding the red deers, body and antlers, infection with diseases and parasites. To find out whether the feeding ration is suitable for the needs of the red deers. Work methods – visual observation of the red deers during all seasons, when determining the behaviour peculiarities. Analysis of helminths (helminthovoscopy) – the freshly collected excrements of the red deers are analysed in the laboratory. The exploration of feeding ration – its sufficiency is estimated according to the nourishing quantities in the types of feed and the needs of deers. The observation of rut, calving and various works and operations is performed by taking part directly in them (arranging of harems, vaccination, marking (numbering), etc.). The body morphometry data are collected from the bagged deers. Metering of dropped antlers according to CIC system. Work results – when performing the intensive farming and when the big density of the red deers is estimated, a lot of problems arise. According to the recent data, in the farm of deers in Joniškis region 800 red deers live in the garden of old apple-trees and natural meadows of 150 ha, i.e. 5.3... [to full text]
23

Elninių žvėrių populiacijų valdymas ir jų įtaka miško atkūrimui Rokiškio miškų urėdijos Vyžuonos girininkijoje / Deer Populations Game Management And Their Impact On The Regeneration Of The Forest In Rokiskis Forest Stewardship, In Vyzuona Forestry

Zamaliauskas, Mantas 21 June 2010 (has links)
Darbo objektas. VĮ Rokiškio miškų urėdijos Vyžuonos girininkijos elninių žvėrių populiacijos, jų valdymas, įtaka miško atkūrimui, bei miško želdinių apsaugos priemonės ir jų efektyvumas. Darbo tikslas. Įvertinti VĮ Rokiškio miškų urėdijos Vyžuonos girininkijos elninių žvėrių populiacijas, jų gyvenamą aplinką bei poveikį miškui. Darbo metodai. Literatūrinės loginės analizės ir sisteminės atrankinės apskaitos. Darbo rezultatai. Vyžuonos girininkijos miškuose gyvena šie elniniai žvėrys: Taurieji elniai ( tankis 10,6 vnt.../1000ha.); Briedžiai (tankis 2,4 vnt.../1000ha.); Stirnos (tankis 80 vnt.../1000ha.) Atsižvelgiant į poveikį miško želdiniams bei žėliniams laupant žievę, elninių žvėrių gausą reikėtų išlaikyti nepakitusią. Elninių žvėrių naudojimas yra per mažas. Pagrindinė rūšis turėtų būti taurusis elnias, šalutinė – stirna, nepageidautina rūšis turėtų būti briedis. Miško želdiniai bei žėliniai nuo elninių žvėrių galimo neigiamo poveikio yra saugomi. Vyžuonos girininkijoje dažniausiai naudojama apsaugos priemonė yra repelentai. 2009 - 2010 metų žiemą saugomas plotas sudarė 44,9 ha. / Object of work. Rokiskis Forest Enterprise Forestry Vyžuonų game deer population management, the influence of forest regeneration and forest plantations, protection measures and their effectiveness. Purpose of work. To evaluate the population of the cervines , their surroundings and their influence to the forest. The methods of work. The logical analyses of the literature and systematic rating. The work results. Cervines living in the forests of the forestry Vyzuona are: Red deer (density 10,6 units/1000 ha) Moose (density 2,4 units/1000 ha) Hind (density 80 units/1000 ha) Considering the influence to sprouts and young growth the population should stay consistent. The use of the cervines is too low. Main species should be red deer, secondary hind, moose should be unacceptable. The forest sprouts and young growth have been protected from negative effects or cervines. In the forestry of Vyzuona mainly the repellents are used for the protection. In the year 2009-2010 the protected area was 44.9 ha.
24

Studies of seasonality in red deer (Cervus elaphus) : with special emphasis on the reproductive physiology of red deer hinds

Duckworth, Janine Alma January 1992 (has links)
Four trials were conducted to investigate factors controlling the seasonal onset of reproductive activity in red deer hinds. Firstly (Chapter 4), the role of photorefractoriness to long daily photoperiods in the initiation of the seasonal reproductive activity in breeding red deer hinds was examined. Red deer hinds (n=10) were prematurely exposed to a long daily photoperiod of 15.3 h from 22 July to 8 November 1986 i.e. winter-spring (EPW), or maintained under natural photoperiods (NP). Six hinds experienced the natural changes in daily photoperiod until mid-summer but were exposed to a 15.5 h of light each day from 30 January to 30 April 1987, i.e. summer-autumn (EPS), whilst hinds in the other groups experienced naturally decreasing daily photoperiods. On 5 occasions (July 1986, January, February, March and April 1987), blood samples were collected from 4 NP and 4 EPW hinds every 20 minutes for 4 h to monitor secretion of luteinising hormone and half hourly for another 4 h following an i.v. injection of 2 µg GnRH to measure pituitary responsiveness. In January, March and April 1987 EPS hinds were also intensively sampled for 4 h. Plasma progesterone concentrations and mean date of calving indicated that the onset of breeding activity was not affected by light treatment in the EPW hinds but was delayed by 3 weeks in the EPS hinds. In contrast, supplementary lighting caused a premature elevation of plasma prolactin concentrations and advanced pelage moulting in EPW hinds only. Plasma LH secretion patterns indicated that LH pulse frequency and mean LH concentrations were greater during the breeding season than during pregnancy or, seasonal or postpartum, anoestrus. The reduction in LH secretion was partially explained by a diminished pituitary responsiveness to GnRH. Daily plasma melatonin secretion patterns indicated that the duration of the nocturnal increase in melatonin concentrations was responsive to changes in photoperiod and provided a suitable endocrine signal for measuring day length. The results suggest that, unlike the sheep and prepubertal red deer hind, the onset of seasonal breeding activity in breeding red deer hinds is not affected by long daily photoperiods in spring but is delayed if the autumnal decrease in daily photoperiod is delayed. Therefore neither the development of photorefractoriness nor the spring increase in daily photoperiods initiated the transition from seasonal anoestrus to reproductive activity in the breeding hind. However, long daily photoperiods may have entrained the annual cycle of pelage shedding and prolactin secretion. It is possible that the neuroendocrine pathway by which photoperiodic signals entrain the seasonal cycle of reproduction is separate from those which regulate other seasonal events in the breeding red deer hind. Secondly (Chapter 5), in a study of seasonality of reproduction, 4 pubertal hinds were monitored for live weight and plasma LH and progesterone concentrations from December 1987 to October 1988 (i.e. 12-22 months of age). In addition the pattern of LH secretion was also studied in 4 ovariectomised pubertal hinds implanted s.c. with controlled release implants containing 12 mg oestradiol-17β between 4 March and 25 May and between 15 June and 19 September, 1988. On several occasions (15 December, 29 February, 15 March, 24 April, 14 June, 29 June, 18 September (all hinds) and 3 October (ovariectomised hinds only) blood samples were collected every 20 minutes for 4 h to monitor secretion of luteinising hormone and following an i.v. injection of 2 µg GnRH to measure pituitary responsiveness. Plasma progesterone profiles indicated that 4-6 ovarian cycles, lasting about 19 d each, occurred in each intact hind. Regular ovarian cycles commenced in late April (26 April ± 3.4 d, mean ± s.e.m.) and ceased 3 months later in July (21 July ± 7.2 d). The number of LH pulses in the intact hinds was higher in June (1-2 pulses/4 h) than in the non-breeding season (< 1 pulse/4 h) probably due to a seasonal increase in GnRH secretion. It appears that the seasonal increase in LH pulsatility and onset of reproductive activity in the entire hinds were temporally related to a reduction in the sensitivity of LH secretion to the negative feedback effects of oestradiol in ovariectomised pubertal hinds. In the third trial (Chapter 6), 20 male and 20 female red deer calves were immunised at birth against a melatonin conjugate or injected with adjuvant only (controls). Booster injections were given on 5 occasions over the next 2 years. Stags which produced significant melatonin binding activity in response to immunisation, were heavier than the controls between 7 and 11 months of age and at 16, 20, 30 and 34 months of age. A similar but smaller effect on live weight was seen in the immunised hinds. Immunisation against melatonin did not affect the calving date of the hinds or antler development and time of casting of antlers in the stags. These results indicated that disruption of the photoperiodic signal by immunisation against melatonin may have prevented the entrainment of annual rhythms in feed intake and growth but without affecting the seasonal cycles in antler growth and ovarian activity. Finally in a series of 3 trials (Chapter 7), anoestrous red deer hinds were induced to ovulate with the GnRH analogue, buserelin. Hinds were pre-treated with intravaginal devices containing 0.6 g progesterone (CIDR-Type S) for 14 days prior to CIDR withdrawal on 4 March. In Year 1, 15 hinds were treated with 1 CIDR each and 8 hinds were injected i.m. with 4 µg buserelin (a GnRH analogue) at CIDR removal followed by 2nd injection of 10 µg 48 h later. In Year 2, 16 hinds were treated with 2 CIDRs each and 8 hinds were injected Lm. with 4, 3, 2, 2 and 10 µg buserelin at -48, -24, 0, 24 and 48 h respectively from CIDR withdrawal. In Year 3, 15 hinds were treated with 2 CIDRs and 11 hinds (Groups Band BO) injected with buserelin identical to the protocol in Year 2. At CIDR withdrawal 6 of these buserelin treated hinds (Group BO) and 4 other progesterone-primed hinds (Group 0) were injected with 500 µg oestradiol benzoate. In addition, during the breeding season, 4 hinds (Group C) were treated with double CIDRs only for 14 d from 1 April. When oestrous behaviour and the pattern of plasma LH secretion were monitored in Year 3, oestrous behaviour was less noticeable and delayed in Group B hinds and peak LH levels were lower and increased later relative to Group 0, BO and C hinds. Two weeks after CIDR withdrawal, 6 buserelin-treated hinds in both Year 1 and Year 2, and 3/5 B, 2/4 0, 3/6 BO and 4/4 C group hinds in Year 3 had a single corpus luteum present. Plasma progesterone concentrations were elevated for about 12 d in most hinds with a corpus luteum in Year 2 and in most B, BO and C Group hinds in Year 3. However, progesterone secretion was low in several Year 1 and all Group 0 hinds in Year 3 indicating that the induced corpora lutea in these hinds were functionally subnormal. There was no evidence that any of the buserelin-induced ovulations resulted in pregnancy, probably because the induced ovulations were not accompanied by normal hormonal and behavioural patterns. The experiments described in this thesis have contributed to our understanding of the regulation of seasonal breeding in red deer hinds. This knowledge may eventually enable reproductive activity to be effectively manipulated, thereby improving the efficiency of deer production systems.
25

Comparative nutrition and energy metabolism of young red deer (Cervus elaphus) and red x elk hybrid deer

Judson, Howard Glenn January 2003 (has links)
Elk (Cervus elaphus spp) are widely used as a terminal sire in the New Zealand deer industry because elk red deer crosses are heavier at 12 months of age than pure-bred red deer (Cervus elaphus) and therefore better fit market demands. However, it is unclear whether nutritional requirements differ between genotypes. A series of experiments compared young (4 - 12 months) red deer and red deer-elk cross (hybrids) in various aspects of their nutrition. Single genotype groups (10-15) of red deer and hybrid weaner stags were offered one of four pasture allowances (2 to 12 kg DM/head/day) on a rotationally grazed mixed ryegrass - white clover pasture system for 9 weeks in winter (June-July), spring (October-December) and summer (February - March). Stags were weighed and given a new allocation of pasture weekly. Pre-grazing pasture mass ranged from 800 kg DM/ha for low pasture allowances to 4500kg DM/ha for higher allowances. Winter live-weight gain was low (40-80 g/day), relatively unaffected by pasture allowance and similar for both genotypes. In spring however, hybrids gained live-weight on average 100 g/day more than red deer across all pasture allowances and the response to additional pasture allowance was large (110 g/day at 2kg DM/head/day to 300 g/day at 9.5 kg DM/head/day). At the highest pasture allowance, hybrids grew faster (350 g/day) than red deer (250 g/day), although red deer were able to achieve this live-weight gain when offered less pasture (4 vs 12 kg DM/head/day, respectively). Summer live-weight gain was lower for both genotypes and responded less to increases in pasture allowance than during spring. A second experiment compared the live-weight gain of both genotypes at ad lib feeding in an indoor environment where intake could be accurately measured. A group of red deer (n =15) and a group of hybrid (n =15) weaner stags were housed indoors during winter (3 June - 27 August) and spring (16 October - 16 December) and fed a pelleted grain based ration ad lib. Mean daily intake for each group (kg DM/head/day) was calculated as the difference between feed offered and feed refused. Hybrids had a significantly higher (P< 0.05) absolute DM intake compared with red deer in both seasons, although when expressed on a metabolic body weight basis, there was no difference between genotypes irrespective of season. Live-weight gain during winter did not differ significantly between genotypes regardless of whether it was expressed on an absolute or metabolic weight basis. Spring live-weight gain, expressed both on an absolute and metabolic live-weight basis, was significantly higher for hybrids compared with red deer (P<0.05). Red deer and hybrids increased their feed intake from winter to spring by 20% and 24% respectively on a metabolic body weight basis. Although the difference between genotypes in their seasonal increase in intake was relatively small there was a large difference in their pattern of live-weight gain. Red deer exhibited a 34% and hybrids a 76% seasonal increase in live-weight gain expressed on a metabolic live-weight basis from winter to spring. These results indicate the greater rate of live-weight gain displayed by hybrids compared with red deer was not associated with a greater ad lib intake (expressed on a metabolic body weight basis) and the seasonal increase in live-weight gain is greater for hybrids than for red deer. A further experiment estimated the energy requirement for maintenance of both genotypes. Five deer of each genotype were housed in separate pens (3.5m²) during winter (3 June - 27 August) and spring (16 October - 16 December) and randomly assigned to one of 5 feeding levels (0.5, 0.6, 0.7, 0.8, or 0.9 times estimated ad lib intake of l.5 and l.7 kg DM/head/day during the winter and 3.0 and 3.3 kg DM/head/day during the spring for red deer and hybrids, respectively. Maintenance requirement was determined by regression analysis of live-weight gain on ME intake. Although there was no seasonal effect on the live weight gain response to intake there was a significant genotype effect. To maintain live weight during either season, hybrids required a higher ME intake (0.52 MJ ME/W0.75/day compared with red deer 0.41 MJ ME/W0.75/day). The rate of increase in live weight gain to increasing intake declined as intake increased and more so for red deer than hybrids. The final experiment in the series involved individually housed deer and aimed to more precisely determine differences in maintenance requirement and examine the difference in composition of gain between genotypes. In addition, in vivo apparent DM digestibility was measured in both genotypes. Red deer (n=7) and hybrid weaner stags (n=7) were housed in individual pens for a period of 8 weeks in both winter (July - August) and spring (November - December) and offered one of 7 feeding levels which ranged from maintenance to ad lib. During each 8 week experimental period, live weight gain, apparent digestibility and feed intake were measured. Immediately prior to, and at the conclusion of each 8 week period body composition was estimated using computer-assisted topography (CT scan). In winter, there was no significant difference in the live weight gain response to intake although red deer tended to have a higher (44 vs 55 MJ/kg) requirement for gain than hybrids. In spring, red deer had a lower requirement for maintenance (0.35 vs 0.47 MJ ME/W0.75/day) but a greater requirement for live weight gain (64 vs 35 MJ/kg) than hybrids. In spring, mean ad lib intake was about 30% higher than in winter and was greater for hybrids than for red deer. Energy retention in whole body (kJ/W0.75/day) did not differ between genotypes in either winter or spring but both the energy requirement for zero energy balance (0.59 vs 0.48 MJ ME/W0.75/day) and the efficiency of utilisation (0.37 vs 0.24) was greater in spring than in winter. The disparity between live weight gain and whole body weight gain may have been due to differences in gut fill. There was no significant difference between genotypes in relative growth coefficients for lean, bone or adipose tissue in whole body. However hybrids tended to have a higher winter and lower spring growth coefficient for fat compared with red deer. Growth coefficients for adipose, lean and bone, respectively were 0.983, 1.063 and 1.026 for winter and 1.02, 0.708 and 1.727 for spring. At the same whole body weight, deer in October had less adipose tissue than in August. It is unclear whether this represents a strategy for rapid spring growth or is an artefact of experimental protocol. Apparent dry matter digestibility (DMD) did not differ between genotypes but was higher by between 7 and 15 percentage units in winter compared with spring. Unexpectedly, digestibility was positively correlated with intake. Digestibility increased by 2.6 percentage units for every 10g DM/W0.75/day increase in either season in one group and 4.1 and 2.1 percentage units for deer in winter and spring respectively in another group. Errors in faecal collection were discounted as causes of the unexpected result.
26

Role of thyroid hormones in the neuroendocrine control of seasonal reproduction in red deer hinds

Anderson, Greg Muir January 1997 (has links)
A series of eight experiments was conducted to investigate the requirement for thyroid hormones in neuroendocrine processes which lead to the seasonally anoestrous state in red deer hinds. The first two experiments used thyroidectomized, ovariectomized, oestradiol-treated hinds which received various thyroid hormone replacement treatments (n=5 per group) to investigate the timing and dose-responsiveness of thyroid hormones in bringing about seasonal oestradiol-induced suppression of plasma LH concentration. A significant seasonal decline in mean plasma LH concentration during September (coinciding with the onset of anoestrus in entire cycling hinds in New Zealand) was observed in all thyroidectomized hinds in both experiments regardless of T₄ or T₃ treatment. When oestradiol implants were removed in November or December, mean plasma LH concentrations increased significantly in all but one of hinds in which T₄ had been administered at very low doses by subcutaneous implants, and mean plasma LH concentrations and LH pulse amplitude increased in approximately half of hinds administered T₃ at varying doses by subcutaneous injections over a one-week period in October. These results suggested that thyroid hormones are not required for steroid-dependent reproductive suppression, but could possibly play a role in steroid-independent suppression of LH secretion. Because problems were encountered in delivering appropriate doses of thyroid hormones in both experiments, further confirmation of these findings was required. Therefore in the next experiment the role of thyroid gland secretions was examined in euthyroid (n=5) and thyroidectomized (n=4) ovariectomized hinds treated with oestradiol implants. These implants were removed for about one month on three occasions to examine the effect of thyroidectomy on steroid-independent control of seasonal LH secretion. During the non-breeding season basal and GnRH-induced plasma LH concentrations declined in all hinds in the presence of oestradiol, but returned to breeding season levels when oestradiol was withdrawn in November. In a concurrent experiment, thyroidectomy of ovary-entire hinds (n=7) during the breeding season prevented the cessation of oestrous cyclicity in spring; this was in contrast to oestrous cyclicity in T₄replaced (n=4) or euthyroid control (n=5) hinds which ceased to occur in early September. Collectively, these results indicate that thyroid hormones are required for the termination of the breeding season in cycling red deer hinds and that this action occurs via steroid-independent neuroendocrine pathways. Two experiments were conducted using neurotransmitter receptor agonists and antagonists to identify neural pathways in the brain which mediate LH suppression by oestradiol and by steroid-independent mechanisms, and to test if the thyroid gland is required for activation of these pathways during the non-breeding season. It was concluded from the lack of plasma LH responses to dopaminergic and opioidergic agonists and antagonists in ovariectomized and ovariectomized, thyroidectomized hinds (n=5) that neural pathways involving dopamine-D₂receptors do not mediate oestradiol-induced seasonal suppression of plasma LH concentrations, and neither dopaminergic or opioid neural pathways mediate non-steroidal suppression of plasma LH concentrations. However preliminary evidence was obtained for a stimulatory role of serotonergic neural pathways in controlling LH secretion. Another experiment was conducted to identify when the steroid-independent mechanisms which suppress LH concentrations during the non-breeding season are responsive to thyroid hormones. T₄treatment at the beginning of or during the non breeding season was effective in bringing about suppression of plasma LH concentration in thyroidectomized, ovariectomized hinds (n=5 per group), but this action of thyroid hormones did not occur during the breeding season. These results show that the steroid-independent mechanisms which contribute to seasonal suppression of plasma gonadotrophin concentrations require thyroid hormones to be present only from around the time of the end of the breeding season for their normal expression, and they remain responsive to thyroid hormones after this period. Lastly, the feasibility of achieving out-of-season breeding using thyroidectomized hinds (n=9) was evaluated by comparing oestrous behaviour, ovulation and pregnancy rates to those of euthyroid control hinds (n=7) following synchronization of oestrous cycles. There was a non-significant trend for a greater occurrence of oestrous behaviour and ovulation in thyroidectomized hinds compared with euthyroid controls during the non-breeding season, but the pregnancy rate following out-of season mating with a thyroidectomized stag was low, suggesting that a side effect of thyroidectomy may be impaired fertility. Six out-of-season pregnancies were obtained from eight matings, however because three of these pregnancies occurred in euthyroid control hinds no improvement in out-of-season reproductive performance could be attributed to thyroidectomy. It is likely that if the actions of the thyroid glands are to be exploited as a tool for achieving out-of-season breeding in this species, techniques will have to be developed for specifically blocking or overcoming the effects of thyroid hormones on the reproductive neuroendocrine centres without causing general hypothyroidism and its associated side-effects.
27

A stepwise approach to understanding and effectively mitigating human-wildlife interactions

Rodríguez, Rocío A. Pozo January 2017 (has links)
The study of conflicts in conservation (also known as human-wildlife conflicts) is a growing field of research in areas where people and wildlife interact, because of the negative impacts each can have on the other. Addressing conflicts is certainly challenging because of the complexities of considering diverse interests from numerous stakeholders and the specific ecological and socio-economic characteristics of a given study system. No matter how complex the system under study is, the aim is in all cases to find effective and sustainable mitigation strategies for local people, as well as for wildlife conservation and local authorities. In this thesis, I look at two of the preliminary steps required to address conservation conflicts and develop efficient long-lasting management solutions: the gathering of ecological data and the assessment of mitigation strategies in the field. To do this, I use two case studies: crop-foraging by African elephants (Loxodonta africana) in northern Botswana, and selective hunting of the red deer (Cervus elaphus) population on the Isle of Rum in Scotland. In Chapter 2, I built a baseline for the level of conflict in the Okavango Delta Panhandle (Botswana) using temporal trends of crop-foraging by elephants as an index of the level of conflict, and subsequently looked at how this relates to trends in agricultural land allocated in the study area, as well as with trends in human and elephant population size. In Chapter 3, I mapped the distribution of the local population of elephants and assessed its interaction with landscape features and sites where crop-foraging events had been recorded. In both chapters (2 & 3) I found that -in general- the number of elephants was not a determinant of the level of conflict in the study area, but that the spatiotemporal distribution of the species as well as the spatial and temporal scales considered were. In the second half of my thesis, I assessed the effects of two common conflict mitigation methods: the use of deterrents (Chapter 4) and lethal control (Chapter 5). I first evaluated the effectiveness of chilli-briquettes in deterring elephants and secondly, I used a modelling approach to predict the demographic effects of increasing levels of selective hunting in a male red deer population. I found that both mitigation methods showed unexpected results, which would not have been detected had I not tested for them. This thesis highlights the advantages of applying methods that are based on informed decisions in areas of conflict, as well as the value of sharing results in conservation management. My findings contribute towards a better understanding of the negative impacts of human-wildlife interactions, which often lead to conservation conflicts, as well as contributing protocols and methodologies that can be adapted and applied elsewhere.
28

Rozbor faktorů ovlivňujících welfare jelena lesního / Analysis of factors affecting the welfare of red deer

PŘICHYSTALOVÁ, Michala January 2012 (has links)
Red deer (Cervus elaphus) is a frequent subject of human interest. It can be managed in the wild, can be intensively bred in game preserves, can be the subject of game farming or bred as a pet, subspecies of red deer occur in the zoos. In the management of deer in the wild can not fully eliminate all negative impacts on the welfare, management of deer in the game preserves should follow optimal breeding conditions completely. The aim of this work was to evaluate the extent to which the red deer management in the Czech Republic is to ensure welfare. There is a list of analysis of reports of the red deer management, statements of the environmental analysis of the red deer and livestock conditions in selected game preserves.
29

Změna habitatových preferencí jelena evropského (Cervus elaphus) v Národním parku Šumava / Red deer (Cervus elaphus) habitat preferences change in the Šumava National Park

Lachová, Barbora January 2021 (has links)
6 Abstract The red deer (Cervus elaphus) is a widespread species of so-called grazers in Central Europe, which significantly affects the functioning of forest ecosystems. While in most areas of red deer distribution, its stocks are regulated within hunting and forestry management, within the Šumava National Park there is the largest non-intervention area with hunting restrictions in Central Europe outside the Alpine region. The Šumava NP is also dynamic environment. There is a change in habitat conditions started mainly by windstorm Kyrill and subsequent bark beetle gradation. There has also been a change in terms of habitat management (new zoning, different forest management practices). The thesis contains an extensive dataset of a total of 34 doe monitored by GPS telemetry collars, from two time horizons. A spatiotemporal analysis of the preferences of land cover, altitude, slope and orientation of slopes and distance to anthropogenic structures is performed. The results of this analysis reaffirm that the behaviour of deer in the daily and annual cycle is controlled mainly by food requirements and also showed the effect of anthropogenic disturbance, which significantly modifies the pattern of land use due to the distance from the source of disturbance. The current occurrence is still controlled by...
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Investigations into the roles of potassium channels in hair growth. Studies confirming the presence of several ATP-­sensitive potassium (K+ATP) channels in hair follicles and exploring their mechanism of action using molecular biological, cell culture, organ culture and proteomic approaches.

Zemaryalai, Khatera January 2010 (has links)
Hair disorders cause significant distress. The main, but limited, treatment for hair loss is minoxidil, an ATP-­sensitive potassium (KATP) channel opener whose mechanism of stimulation is unclear. The regulatory component of KATP channels has three forms: SUR1, SUR2A and SUR2B which all respond to different molecules. Minoxidil only opens SUR2B channels, though SUR1 and SUR2B are present in human hair follicles. To expand our understanding, the red deer hair follicle model was used initially. Deer follicles expressed the same KATP channel genes as human follicles when growing (anagen), but no channels were detected in resting follicles. This reinforces the importance of KATP channels in active hair growth and the usefulness of the deer model. To assess whether SUR1 KATP channels are actually involved in human hair growth, the effects of a selective SUR1 channel opener, NNC55-­9216, on scalp follicle growth in organ culture was examined. NNC55-­9216 stimulated anagen; its effect was augmented by minoxidil. This creates the potential for more effective pharmaceuticals to treat hair loss via SUR1 channels, either alone or in combination with minoxidil. The dermal papilla plays a crucial regulatory role in hair follicle activity determining the type of hair produced. Minoxidil had no effect on dermal papilla cell proliferation, but altered the profile of proteins produced when assessed by proteomics. Further research into the roles of KATP channels and greater understanding of the significance of these protein changes should enhance our knowledge of hair biology and help the development of new, improved therapies for hair pathologies.

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