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1.
Sci Rep ; 10(1): 17908, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087737

RESUMO

Large carnivores have experienced considerable range contraction, increasing the importance of movement across human-altered landscapes between small, isolated populations. African wild dogs (Lycaon pictus) are exceptionally wide-ranging, and recolonization is an important element of their persistence at broad scales. The competition-movement-connection hypothesis suggests that adaptations to move through areas that are unfavorable due to dominant competitors might promote the ability of subordinate competitors (like wild dogs) to move through areas that are unfavorable due to humans. Here, we used hidden Markov models to test how wild dog movements were affected by the Human Footprint Index in areas inside and outside of South Luangwa National Park. Movements were faster and more directed when outside the National Park, but slowed where the human footprint was stronger. Our results can be directly and quantitatively applied to connectivity planning, and we use them to identify ways to better understand differences between species in recent loss of connectivity.


Assuntos
Migração Animal/fisiologia , Animais Selvagens/fisiologia , Comportamento Animal/fisiologia , Carnívoros/fisiologia , Carnívoros/psicologia , Ecossistema , Cadeias de Markov , Densidade Demográfica , Animais , Espécies em Perigo de Extinção , Extinção Biológica , Humanos , Parques Recreativos , África do Sul , Fatores de Tempo
2.
PLoS One ; 9(8): e105042, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25126849

RESUMO

Human-carnivore conflict continues to present a major conservation challenge around the world. Translocation of large carnivores is widely implemented but remains strongly debated, in part because of a lack of cost transparency. We report detailed translocation costs for three large carnivore species in Namibia and across different translocation scenarios. We consider the effect of various parameters and factors on costs and translocation success. Total translocation cost for 30 individuals in 22 events was $80,681 (US Dollars). Median translocation cost per individual was $2,393, and $2,669 per event. Median cost per cheetah was $2,760 (n = 23), and $2,108 per leopard (n = 6). One hyaena was translocated at a cost of $1,672. Tracking technology was the single biggest cost element (56%), followed by captive holding and feeding. Soft releases, prolonged captivity and orphaned individuals also increased case-specific costs. A substantial proportion (65.4%) of the total translocation cost was successfully recovered from public interest groups. Less than half the translocations were confirmed successes (44.4%, 3 unknown) with a strong species bias. Four leopards (66.7%) were successfully translocated but only eight of the 20 cheetahs (40.0%) with known outcome met these strict criteria. None of the five habituated cheetahs was translocated successfully, nor was the hyaena. We introduce the concept of Individual Conservation Cost (ICC) and define it as the cost of one successfully translocated individual adjusted by costs of unsuccessful events of the same species. The median ICC for cheetah was $6,898 and $3,140 for leopard. Translocations are costly, but we demonstrate that they are not inherently more expensive than other strategies currently employed in non-lethal carnivore conflict management. We conclude that translocation should be one available option for conserving large carnivores, but needs to be critically evaluated on a case-by-case basis.


Assuntos
Carnívoros , Espécies em Perigo de Extinção/economia , Meios de Transporte/economia , Acinonyx/fisiologia , Animais , Carnívoros/fisiologia , Feminino , Humanos , Hyaenidae/fisiologia , Masculino , Namíbia , Panthera/fisiologia
3.
Environ Manage ; 52(6): 1334-40, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24202281

RESUMO

Alleviating human-carnivore conflict is central to large carnivore conservation and is often of economic importance, where people coexist with carnivores. In this article, we report on the patterns of predation and economic losses from wild carnivores preying on livestock in three villages of northern Baima Xueshan Nature Reserve, northwest Yunnan during a 2-year period between January 2010 and December 2011. We analyzed claims from 149 households that 258 head of livestock were predated. Wolves (Canis lupus) were responsible for 79.1 % of livestock predation; Asiatic black bears (Selenarctos thibetanus) and dholes (Cuon alpinus) were the other predators responsible. Predation frequency varied between livestock species. The majority of livestock killed were yak-cattle hybrids or dzo (40.3 %). Wolves killed fewer cattle than expected, and more donkeys and horses than expected. Wolves and bears killed more adult female and fewer adult male livestock than expected. Intensified predation in wet season coincided with livestock being left to graze unattended in alpine meadows far away from villages. On average, carnivore attacks claimed 2.1 % of range stock annually. This predation represented an economic loss of 17 % (SD = 14 %) of the annual household income. Despite this loss and a perceived increase in carnivore conflict, a majority of the herders (66 %) still supported the reserve. This support is primarily due to the benefits from the collection of nontimber resources such as mushrooms and medicinal plants. Our study also suggested that improvement of husbandry techniques and facilities will reduce conflicts and contribute to improved conservation of these threatened predators.


Assuntos
Criação de Animais Domésticos/métodos , Carnívoros/fisiologia , Conservação dos Recursos Naturais/métodos , Gado , Comportamento Predatório/fisiologia , Criação de Animais Domésticos/economia , Animais , Bovinos , China , Conservação dos Recursos Naturais/estatística & dados numéricos , Feminino , Humanos , Entrevistas como Assunto , Masculino , Estações do Ano , Lobos
4.
PLoS One ; 8(1): e52458, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23326333

RESUMO

Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where carnivore conservation is being attempted on private lands.


Assuntos
Agricultura/métodos , Carnívoros/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Ecossistema , Acinonyx/crescimento & desenvolvimento , África Austral , Agricultura/economia , Agricultura/tendências , Animais , Animais Selvagens/classificação , Animais Selvagens/crescimento & desenvolvimento , Animais Selvagens/fisiologia , Canidae/crescimento & desenvolvimento , Carnívoros/classificação , Carnívoros/fisiologia , Conservação dos Recursos Naturais/economia , Humanos , Hyaenidae/crescimento & desenvolvimento , Leões/crescimento & desenvolvimento , Gado/crescimento & desenvolvimento , Gado/fisiologia , Namíbia , Panthera/crescimento & desenvolvimento , Dinâmica Populacional , Comportamento Predatório/fisiologia , Especificidade da Espécie
5.
Integr Zool ; 7(2): 210-26, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22691204

RESUMO

Human-wildlife conflict (HWC) is a conservation concern that increasingly threatens the continued existence of some of the world's most endangered species. With an increase in human population, urban sprawl and subsequent encroachment on wild land, human and wildlife interaction has become inevitable. In the majority of cases, this interaction results in a negative outcome for humans, wildlife or both. In China, these key elements, along with a decrease in wild prey species, have resulted in the expansion of HWC encounters, and the need for alleviating this conflict has become a conservation priority. Loss of human life, livestock and/or crops is most often the catalysts that fuel HWC. Techniques to alleviate conflict around the world have included preventative measures and mitigation techniques, such as financial compensation and other incentive programs. Both types of measures have had variable success. We review the current status of human-carnivore conflict management in China, and, drawing lessons from around the globe, we make recommendations for improving conservation management in China. For example, an increase in law enforcement in nature reserves is vital to reducing human disturbance in prime carnivore habitat, thereby reducing conflict encounters. Also, modifications to current wildlife compensation programs, so that they are linked with preventative measures, will ensure that moral hazards are avoided. Furthermore, investigating the potential for a community self-financed insurance scheme to fund compensation and increasing efforts to restore wild prey populations will improve the outcome for wildlife conservation. Ultimately, HWC management in China will greatly benefit from an integrative approach.


Assuntos
Animais Selvagens , Carnívoros/fisiologia , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Ecossistema , Atividades Humanas , Animais , China , Compensação e Reparação/legislação & jurisprudência , Conservação dos Recursos Naturais/legislação & jurisprudência , Humanos , Seguro/economia , Aplicação da Lei/métodos , Comportamento Predatório/fisiologia
6.
Reprod Domest Anim ; 47(1): 164-75, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21883515

RESUMO

Carnivora is one of the most species-rich order of Mammalia. Some species, e.g. domestic cats, dogs and ferrets, are among the most popular pets; others, such as minks and farmed foxes, have economic value for the fur breeding industry. Still others, such as tigers, bears and other top predators, have great impact on the health of natural ecosystems. Most if not all Carnivora species have great cultural and aesthetic importance for man. There are enormous differences between mammalian species in reproductive physiology, and it is not surprising that reproductive technologies can be used with high efficiency with some animal groups, e.g. most farm animals and laboratory rodents, but are very laborious when used with Carnivora species, which often possess unique reproductive traits. The efficiency of assisted reproductive technology (ART) applied to semi-domestic, non-domestic and especially to endangered species of Carnivora remains extremely low in most cases, and often the first positive result reported is the only instance when ART has been successful with that species. Although there are approximately 270 species in the Carnivora order, to the best of our knowledge, successful published attempts to apply ART have been reported for only four families: Mustelidae, Felidae, Canidae and Ursidae. The main achievements in ART, embryo technology in particular, for these families of Carnivora, together with challenges and problems, are reviewed in the relevant sections.


Assuntos
Carnívoros/genética , Genoma , Técnicas Reprodutivas/veterinária , Animais , Canidae , Carnívoros/fisiologia , Clonagem de Organismos , Criopreservação/métodos , Criopreservação/veterinária , Espécies em Perigo de Extinção , Felidae , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Masculino , Mustelidae , Gravidez , Técnicas de Reprodução Assistida/veterinária , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Bancos de Tecidos , Ursidae
7.
Proc Natl Acad Sci U S A ; 108(34): 13937-44, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21873181

RESUMO

One of the greatest challenges in biodiversity conservation today is how to facilitate protection of species that are highly valued at a global scale but have little or even negative value at a local scale. Imperiled species such as large predators can impose significant economic costs at a local level, often in poverty-stricken rural areas where households are least able to tolerate such costs, and impede efforts of local people, especially traditional pastoralists, to escape from poverty. Furthermore, the costs and benefits involved in predator conservation often include diverse dimensions, which are hard to quantify and nearly impossible to reconcile with one another. The best chance of effective conservation relies upon translating the global value of carnivores into tangible local benefits large enough to drive conservation "on the ground." Although human-carnivore coexistence involves significant noneconomic values, providing financial incentives to those affected negatively by carnivore presence is a common strategy for encouraging such coexistence, and this can also have important benefits in terms of reducing poverty. Here, we provide a critical overview of such financial instruments, which we term "payments to encourage coexistence"; assess the pitfalls and potentials of these methods, particularly compensation and insurance, revenue-sharing, and conservation payments; and discuss how existing strategies of payment to encourage coexistence could be combined to facilitate carnivore conservation and alleviate local poverty.


Assuntos
Carnívoros/fisiologia , Conservação dos Recursos Naturais/economia , Comportamento Predatório/fisiologia , Simbiose/fisiologia , Animais , Internacionalidade
8.
Environ Monit Assess ; 181(1-4): 101-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21181260

RESUMO

Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.


Assuntos
Carnívoros/fisiologia , Monitoramento Ambiental/métodos , Animais , Conservação dos Recursos Naturais , Análise Custo-Benefício , Drenagem Sanitária , Monitoramento Ambiental/economia , Monitoramento Ambiental/instrumentação , Portugal , Meios de Transporte , Gravação em Vídeo
10.
Proc Biol Sci ; 269(1504): 1981-7, 2002 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-12396496

RESUMO

Among all extant mammals, only the female spotted hyena (Crocuta crocuta) mates and gives birth through the tip of a peniform clitoris. Clitoral morphology is modulated by foetal exposure to endogenous, maternal androgens. First births through this organ are prolonged and remarkably difficult, often causing death in neonates. Additionally, mating poses a mechanical challenge for males, as they must reach an anterior position on the female's abdomen and then achieve entry at the site of the retracted clitoris. Here, we report that interfering with the actions of androgens prenatally permanently modifies hyena urogenital anatomy, facilitating subsequent parturition in nulliparous females who, thereby, produce live cubs. By contrast, comparable, permanent anatomical changes in males probably preclude reproduction, as exposure to prenatal anti-androgens produces a penis that is too short and has the wrong shape necessary for insertion during copulation. These data demonstrate that the reproductive costs of clitoral delivery result from exposure of the female foetus to naturally circulating androgens. Moreover, the same androgens that render an extremely unusual and laborious process even more reproductively costly in the female are apparently essential to the male's physical ability to reproduce with a normally masculinized female.


Assuntos
Androgênios/fisiologia , Carnívoros/fisiologia , Genitália Feminina/fisiologia , Genitália Masculina/fisiologia , Troca Materno-Fetal/fisiologia , Reprodução/fisiologia , Caracteres Sexuais , Antagonistas de Androgênios/farmacologia , Androgênios/sangue , Animais , Inibidores Enzimáticos/farmacologia , Feminino , Finasterida/farmacologia , Flutamida/farmacologia , Genitália Feminina/anatomia & histologia , Genitália Feminina/efeitos dos fármacos , Genitália Masculina/anatomia & histologia , Genitália Masculina/efeitos dos fármacos , Masculino , Troca Materno-Fetal/efeitos dos fármacos , Gravidez , Comportamento Sexual Animal/fisiologia , Especificidade da Espécie
11.
Proc Natl Acad Sci U S A ; 97(11): 5954-9, 2000 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-10811901

RESUMO

The use of umbrella and flagship species as surrogates for regional biota whose spatial distributions are poorly known is a popular conservation strategy. Yet many assumptions underlying the choice of surrogate species remain untested. By using biodiversity databases containing spatial incidence data for species of concern for (i) the southern California coastal sage scrub habitat, (ii) the Columbia Plateau ecoregion, and (iii) the continental United States, we evaluate the potential effectiveness of a range of conservation surrogate schemes (e.g., big carnivores, charismatic species, keystone species, wide-ranging species), asking how many species potentially are protected by each scheme and at what cost in each habitat area. For all three databases, we find that none of the surrogate schemes we evaluated performs significantly better than do a comparable number of species randomly selected from the database. Although some surrogate species may have considerable publicity value, based on the databases we analyzed, representing diverse taxa on three different geographic scales, we find that the utility of umbrella and flagship species as surrogates for regional biodiversity may be limited.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Animais , Carnívoros/fisiologia , Conservação dos Recursos Naturais/economia , Bases de Dados Factuais , Ecologia , Plantas , Dinâmica Populacional , Estados Unidos
13.
Philos Trans R Soc Lond B Biol Sci ; 338(1286): 393-407, 1992 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-1362817

RESUMO

Data from post-mortem examinations, population density estimates and long term capture-mark-recapture studies have been combined to look at the pattern of reproductive behaviour and the social factors leading to reproductive failure in badgers in Britain. The results are used to evaluate whether the hypothesis that the defence of oestrous females (as opposed to defence of food resources) best explains territorial behaviour and the social organization of badgers. Badgers in Britain have two peaks of reproductive activity, one immediately post partum and one in the summer/autumn. These coincide with two peaks of ovulation, and in the late winter/spring there is a steep rise in the number of sows carrying blastocysts, to reach an asymptote in June for yearling sows and April in older sows. Measured by their contribution to overall productivity, winter/spring matings were much more important than summer/autumn matings, contributing 65% of total autumn blastocysts in yearling sows and 71% of autumn blastocysts in older sows. The relative importance of the two mating periods is reflected in the seasonal pattern of bite wounding in adult male badgers; minor bite wounding in January-March was 2.3 times as frequent as in August-October, and moderate-extensive bite wounding was 3.1 times more frequent. In the populations studied, pre- and post-natal losses were high, with reproductive failure occurring at all stages of the breeding cycle, so that less than 30% of potential productivity was achieved. Indeed 22% of sows failed to develop blastocysts; these had a lower body mass, less body fat, larger adrenal glands, poorer health and higher bite wound scores than sows with blastocysts. Only 44% of adult sows implanted their blastocysts and proceeded to the end of pregnancy. However, it was less easy to identify features characteristic of sows that did or did not go on to implant their blastocysts. Finally, 35% of sows that produced cubs ceased lactation early, and this loss of entire litters was thought to be due to infanticide by dominant sows. The presence of annexe setts correlates with increased productivity in younger sows, and this is thought to be because annexe setts enable younger sows and their cubs to avoid the aggression of older, more dominant sows. Living in large social groups has no net reproductive gain for adult males or females, and there was a decline in productivity (per adult) with increasing group size.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Carnívoros/fisiologia , Fertilidade , Animais , Feminino , Masculino , Densidade Demográfica , Gravidez , Estações do Ano , Comportamento Social
14.
J Comp Physiol A ; 164(6): 815-24, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2724187

RESUMO

The energetics and hydrodynamics of surface and submerged swimming were compared in the sea otter (Enhydra lutris). 1. Sea otters used two distinct speed ranges that varied with swimming mode. Sustained surface swimming was limited to speeds less than 0.80 m/s, while sustained submerged swimming occurred over the range of 0.60 to 1.39 m/s. 2. Rates of oxygen consumption (VO2) at the transition speed (0.80 m/s) were 41% lower for submerged swimming by sea otters in comparison to surface swimming. 3. Total cost of transport for surface swimming sea otters, 12.56 joules/kg.m, was more than 12 times the predicted value for a similarly-sized salmonid fish. Transport costs for submerged swimming at the same speed was only 7.33 times the predicted value. 4. The allometric relationship for minimum cost of transport in surface swimming birds and mammals was y = 23.87 chi -0.15 where y = cost of transport in joules/kg.m and x = body mass in kg. This regression loosely parallels the relationship for salmonid fish. 5. Correlations between aquatic behavior, morphological specialization, and swimming energetics indicate that the development of swimming in mustelids involved transitions from fore-paw to hind-paw propulsion, and from surface to submerged swimming.


Assuntos
Carnívoros/fisiologia , Locomoção , Lontras/fisiologia , Consumo de Oxigênio , Animais , Feminino , Masculino , Lontras/metabolismo , Natação
15.
J Exp Biol ; 138: 301-18, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3193059

RESUMO

In this study we investigate how speed and stride frequency change with body size. We use this information to define 'equivalent speeds' for animals of different size and to explore the factors underlying the six-fold difference in mass-specific energy cost of locomotion between mouse- and horse-sized animals at these speeds. Speeds and stride frequencies within a trot and a gallop were measured on a treadmill in 16 species of wild and domestic quadrupeds, ranging in body size from 30 g mice to 200 kg horses. We found that the minimum, preferred and maximum sustained speeds within a trot and a gallop all change in the same rather dramatic manner with body size, differing by nine-fold between mice and horses (i.e. all three speeds scale with about the 0.2 power of body mass). Although the absolute speeds differ greatly, the maximum sustainable speed was about 2.6-fold greater than the minimum within a trot, and 2.1-fold greater within a gallop. The frequencies used to sustain the equivalent speeds (with the exception of the minimum trotting speed) scale with about the same factor, the -0.15 power of body mass. Combining this speed and frequency data with previously published data on the energetic cost of locomotion, we find that the mass-specific energetic cost of locomotion is almost directly proportional to the stride frequency used to sustain a constant speed at all the equivalent speeds within a trot and a gallop, except for the minimum trotting speed (where it changes by a factor of two over the size range of animals studied). Thus the energy cost per kilogram per stride at five of the six equivalent speeds is about the same for all animals, independent of body size, but increases with speed: 5.0 J kg-1 stride-1 at the preferred trotting speed; 5.3 J kg-1 stride-1 at the trot-gallop transition speed; 7.5 J kg-1 stride-1 at the preferred galloping speed; and 9.4 J kg-1 stride-1 at the maximum sustained galloping speed. The cost of locomotion is determined primarily by the cost of activating muscles and of generating a unit of force for a unit of time. Our data show that both these costs increase directly with the stride frequency used at equivalent speeds by different-sized animals. The increase in cost per stride with muscles (necessitating higher muscle forces for the same ground reaction force) as stride length increases both in the trot and in the gallop.


Assuntos
Constituição Corporal , Marcha , Locomoção , Mamíferos/fisiologia , Animais , Animais Domésticos/fisiologia , Animais Selvagens/fisiologia , Artiodáctilos/fisiologia , Carnívoros/fisiologia , Mamíferos/anatomia & histologia , Perissodáctilos/fisiologia , Roedores/fisiologia
16.
Physiol Behav ; 37(5): 777-83, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3774908

RESUMO

An analysis of seasonal changes in energy budget of the farmed polecat (Mustela putorius) was performed in subarctic climate. Cyclical variations were found in the body weight of male polecats from maximum values in February (2.1 kg) to minimum values in June-July (1.5 kg). There were only minor seasonal changes in the body weight of females. There was a direct relationship between body weight and voluntary energy intake on one hand (r = 0.89) and an inverse relationship between body weight and locomotor activity (r = -0.88) on the other hand. Energy intake was significantly (p less than 0.05) higher during winter (224 kcal/animal/day) than during summer (142 kcal/animal/day). Total time spent outside the nest was at its maximum during the winter months (60 min/day). The results suggest that in male polecats, changes in absolute food intake induce seasonal changes in body weight. Seasonal changes in locomotor activity seem to be less important in energy balance regulation. The fact that the body weight of females showed only minor seasonal variation supports the role of sexual hormones in the control of the body weight.


Assuntos
Comportamento Animal/fisiologia , Carnívoros/fisiologia , Metabolismo Energético , Animais , Peso Corporal , Ingestão de Energia , Comportamento Alimentar/fisiologia , Feminino , Masculino , Atividade Motora/fisiologia , Estações do Ano , Fatores Sexuais
17.
J Wildl Dis ; 18(3): 339-42, 1982 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7131656

RESUMO

One hundred and three Alaskan gray wolves and 12 wolverines were immobilized in the Nelchina and upper Susitna River Basins of southcentral Alaska between March 1977 and May 1981. Sixty-five wolves were immobilized with a mixture of phencyclidine HCl and promazine HCl (PP/HCl); 38 wolves were immobilized with etorphine HCl (EHCl) and 12 wolverines were immobilized with EHCl or with a mixture of EHCl and xylazine HCl (XHCl). Phencyclidine HCl is no longer commercially available and an assessment of etorphine HCl as a replacement drug was made. Etorphine HCl dosage of 2.5 mg/wolf proved to be a suitable replacement for PP/HCl for immobilizing wolves while 0.7 mg EHCl with 50 mg XHCl appeared suitable for wolverines.


Assuntos
Grupos de População Animal , Animais Selvagens , Carnívoros/fisiologia , Imobilização , Tranquilizantes/farmacologia , Aeronaves , Alaska , Animais , Combinação de Medicamentos , Etorfina/farmacologia , Feminino , Masculino , Fenciclidina/farmacologia , Promazina/farmacologia , Tranquilizantes/administração & dosagem , Xilazina/farmacologia
18.
Acta Anat (Basel) ; 96(4): 478-85, 1976.
Artigo em Alemão | MEDLINE | ID: mdl-1012940

RESUMO

We have amended and added to Fabian's tables giving a functional assessment of individual masticatory muscles. The data in our tables refer only to the temporalis, masseter, pterygoideus medialis, pterygoideus lateralis and digastricus muscles. The weights of these muscles were determined in three fixed human cadavers and the mean values compared with those of apes, carnivores, herbivores and rodents. In humans, the most powerful masticatory muscle is the M. temporalis, followed by the M. massater, as in apes and carnivores. The M. pterygoideus is also one of the most important. This is remarkable, since in the other groups this muscle occupies the last place. This relative strengthening of the M. pterygoideus lateralis is an important characteristic of the human masticatory apparatus. In humans, the difference between the relative weights of the individual masticatory muscles is not nearly so great as in other mammalian groups. The M. pterygoideus lateralis does lie close behind the other two big adductors (Mm temporalis and masseter) but, as regards power and weight, it hardly differs from the M. pterygoideus medialis and the M. digastricus. In humans the strengthening affects not only the M. pterygoideus lateralis but also the M. digastricus. It would seem that these two masticatory muscles could become the key to the understanding of the specific changes in human mastication.


Assuntos
Carnívoros/fisiologia , Hominidae/fisiologia , Mamíferos/fisiologia , Músculos da Mastigação/fisiologia , Roedores/fisiologia , Animais , Humanos , Músculos da Mastigação/anatomia & histologia , Tamanho do Órgão , Especificidade da Espécie
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