Altitude Areas Research Articles

Enhanced hepatic insulin signaling in the livers of high altitude native rats under basal conditions and in the livers of low altitude native rats under insulin stimulation: a mechanistic study

This study was designed to investigate the role of the liver in lowering fasting blood glucose levels (FBG) in rats native to high (HA) and low altitude (LA) areas. As compared with LA natives, besides the improved insulin and glucose tolerance, HA native rats had lower FBG, at least mediated by inhibition of hepatic gluconeogenesis and activation of glycogen synthesis. An effect that is mediated by the enhancement of hepatic insulin signaling mediated by the decreased phosphorylation of TSC induced inhibition of mTOR function. Such effect was independent of activation of AMPK nor stabilization of HIF1α, but most probably due to oxidative stress induced REDD1 expression. However, under insulin stimulation, and in spite of the less activated mTOR function in HA native rats, LA native rats had higher glycogen content and reduced levels of gluconeogenic enzymes with a more enhanced insulin signaling, mainly due to higher levels of p-IRS1 (tyr612).

Altitude-Dependent Prevalence of Canine Granulocytic Anaplasmosis in Romania.

Canine granulocytic anaplasmosis (CGA) is an important tick-borne disease with worldwide distribution. The importance of this disease resides in the ability of Anaplasma phagocytophilum to infect humans and several animal species. The aim of the study was to evaluate the prevalence rate of CGA in different altitudinal areas of Romania. A total of 357 canine blood samples were collected during 2010-2013 from eight counties. To assess the influence of the altitude on A. phagocytophilum prevalence, the samples were collected from four different altitude areas (coastal 0-5 meters; lowland 6-100 meters; hilly areas 200-300 meters; low mountain areas >500 meters). These samples were evaluated for the presence of A. phagocytophilum DNA by amplifying part of the Ankyrin repeat protein (AnkA) gene. A higher prevalence was obtained for coastal compared with remaining areas, suggesting an influence of altitude on the CGA. Moreover, the results suggest an influence of climate and rainfall. In the present research work, we highlight the risk of granulocytic anaplasmosis in Central and Southern Romania, with a greater risk associated to Southern lowland region, especially in coastal areas. The importance of these results resides in the zoonotic potential of the canine A. phagocytophilum strains. In conclusion, the altitude and precipitation level may be risk factors for A. phagocytophilum infection in dogs and other hosts, including humans.

Avaliação da Dispersão de Sementes de Pinus taeda L. pela Análise dos Anéis de Crescimento de Árvores de Regeneração Natural

RESUMO As árvores de Pinus taeda – introduzidas no Brasil em 1880 e em ensaios experimentais em 1936 – têm sido relacionadas na literatura especializada ao processo de invasão biológica de algumas áreas de campos gerais e de altitude dos estados do Paraná e Santa Catarina, de cerrado no estado de São Paulo, de restinga no estado de Santa Catarina e de pampas no estado do Rio Grande do Sul. Os anéis de crescimento anuais formados no lenho das árvores de Pinus taeda constituem importante ferramenta na avaliação do processo de invasão biológica. Com esse objetivo, no presente trabalho avaliou-se a dispersão espacial-temporal de sementes analisando-se os anéis de crescimento do lenho de árvores de Pinus taeda de plantações e de regeneração natural na região de Faxinal do Céu, estado do Paraná. Os resultados possibilitaram determinar a idade e a taxa de crescimento do tronco das árvores de Pinus taeda de plantações, a data da germinação, a área de dispersão das sementes e a taxa de crescimento das árvores de regeneração natural. Os resultados permitem, da mesma forma, discutir o processo de invasão de árvores de Pinus taeda pela dispersão das sementes em áreas limítrofes às plantações florestais.

NEURAL SCALE ANALYSIS OF MILD COGNITIVE IMPAIRMENT IN MIDDLE-AGED AND ELDERLY PEOPLE AT MIDDLE- AND LOW-ALTITUDE AREAS

To compare the prevalence of MCI and characteristics of memory loss in the middle-aged and elderly at middle and low altitude. There were collected 756 participants in low altitude (LA) (Dezhou city, 50 meters above sea level), and 671 participants in middle altitude( MA) (Xining city, 2260 meters above sea level) .Participants come from the Han nationality and living in local urban residents more than 10 years. The MCI questionnaire, ADAS-Cog, MMSE and CDT were used to access the intellectual ability in these participants. 1.There were no statistical differences in the age, sex, and educational degree in the middle and low altitude survey population (P>0.05).The MCI was 95 patients (11.99% prevalence) at LA, however, MCI was 120 patients (16.11% prevalence) in MA (X2=11.767, P<0.01). 2. Comparison between MCI and normal in the different altitudes, there were significant differences in the total score of ADAS-Cog, MMSE and CDT (P<0.01). Compared with the normal at LA, there was significant difference between ADAS-Cog and MMSE in the normal at MA (P< 0.01). 3. Comparison of ADAS-Cog items: the word recognition and word recalling of the MCI both altitude areas had significantly higher than the normal (P<0.01). Compared with the normal and MCI in LA, the normal and MCI in MA were reduced in word recognition and word recalling (P<0.01). 4. Comparison of MMSE items: the ability of calculation and short-time memory of the MCI were decreased compared with normal of LA (P<0.01). The immediate memory, ability of calculation and short-term memory in MCI were decreased than that of normal in MA (P<0.01). Compared with normal and MCI in LA, the normal and MCI in MA were reduced in the immediate memory, ability of calculation and short-term memory (P<0.01). This study found that the prevalence of MCI in the middle-high altitude was higher than that in the plain area. The combined application of ADAS-Cog, MMSE and CDT can increase the diagnostic rate of MCI at Qinghai-Tibet plateau area. These results imply that residents who long term living in chronic hypoxic environment may be a certain influence to the person's cognition.

Analysis of effect of topographical conditions on content of total alkaloid in Coptidis Rhizoma in Chongqin, China

To study ecology suitability rank dividing of the total alkaloid content of Coptis Rhizoma for selecting artificial planting base and high-quality industrial raw material in Chongqing province. Based on the investigation of PCB and DEM data of Chongqing province, the relationship between the total alkaloid content in Coptis Rhizoma and topographical conditions was analyzed by statistical analysis. The geographic information systems (GIS)-based assessment and landscape ecological principles were applied to assess eco logy suitability areas of Coptis Rhizoma in Chongqing. slope, aspect and altitude are main topographical factors that affect the content of the total alkaloid content in Coptis Rhizoma The total alkaloid content in Coptis Rhizoma is higher in the lower altitude, shady slope and bigger slope areas. The total alkaloid content is higher in the south areas of Chongqing province and lower in the northeast. Terrain conditions of the southern region of Chongqing are most suitable for The accumulated of total alkaloid Coptis Rhizoma content.

Geographical altitude, size, mass and body surface area in children (1–4 years) in the Province of Jujuy (Argentina)

Background: Highland child populations show low growth rates.Aim: To evaluate the variation of size, mass and body surface area of Jujenean infants (1–4 years) as a function of geographic altitude.Subjects and methods: Nutritional status of 8059 healthy infants was determined based on weight and height data; body mass index, ponderal index, body surface area, body surface area/mass and ectomorphy were calculated. Variables were standardized with a provincial mean and WHO references. Data were grouped by age, sex and geographic altitude: Highlands (≥2500 masl) and Lowlands (<2500 masl). Chi-square, correlation and t-tests were applied.Results: Highlands infants had higher prevalence of stunting, reduced height, weight, body surface area and ectomorphy; also higher body mass index, ponderal index and body surface area/mass. The population average z-score for height, weight and body surface area was positive in Lowlands and negative in Highlands. The opposite happened with body mass index, ponderal index and body surface area/mass. In Highlands and Lowlands the average z-score reference was negative for weight and height and positive for body mass index. Correlations between indices were high and significant, higher in Highlands.Conclusion: Jujenean children differ in size, mass and body surface area based on the geographical altitude and adverse nutritional and socioeconomic factors.

Analysis of Live Working Safety Distance for 750kV Double Circuit Transmission Line in Different Altitude Areas

In order to determine the required live working safety distance for 750kV double circuit transmission line in different altitude areas of China, by using the test data of 750kV double circuit transmission line in the low altitude areas, and combining the common altitude correction methods, the live working safety distances of different altitude correction methods are obtained. By comparing and analyzing the results of different analysis methods, the required minimum approach distances and minimum combined gap distances of live working are recommended under different working conditions in the altitude of 1000m ~ 5000m areas. The results could provide technical reference for 750kV double circuit transmission line in different altitude areas.

Research progress on the effects of soil freeze-thaw on plant physiology and ecology

Soil freeze-thaw, which mainly refers to repeated freezing and thawing due to changes in soil temperature, is a natural phenomenon in seasonally frozen or permafrost regions. Freeze-thaw not only affects soil physicochemical and biological properties, but also alters the ecophysiological processes of plants. This has been noted to significantly influence the productivity of ecosystems in high latitude and altitude areas with vast frozen grounds. This paper reviewed the effects of freeze-thaw on the physiological and ecological processes of above-ground and below-ground parts of plants and the response characteristics of alpine vegetation ecosystem to different freeze-thaw patterns. The paper summarized the ecophysiological characteristics under different climatic conditions and habitat stresses in terms of photosynthesis, biomass and productivity, root growth and response to moisture and temperature stress. The shortage in studies on soil freeze-thaw and ecophysiological processes of plants were also addressed. It was concluded that frequent soil freezing and thawing dramatically influenced the distribution patterns and ecological functions of vegetation under changing global environment, which was especially stronger in alpine ecosystems.

Role of Food Processing Training and Exposure Visits in Empowering the Rural Women Community

An impact study on food processing training and exposure visits conducted by the Krishi Vigyan Kendra (KVK) during the year 2011-2013 was evaluated. The total number of trainees who attended the programme during 2011-2013 was 200 (including on campus and off campus). The food processing trainees were trained out in the areas such as sorting, grading of agricultural commodities, post harvest technology aspects, making different kinds of pickles and curries, and preparing value added products from different field crops. Four groups, each containing 50 rural women having a minimum educational qualification of 10th (SSC) pass, were selected from the entire district including high altitude and tribal areas. The study revealed that the trainees were able to upgrade their knowledge in different areas of food processing . The study shows that the knowledge of the trainees in the different areas of food processing increased from 36.5% to 87.7%.

Landscape and habitat characteristics associated with fish occurrence and richness in southern Brazil palustrine wetland systems

We investigated the influence of environmental factors in fish communities of 146 palustrine wetlands, covering a wide range of altitude and wetland surface area in Neotropical region. Two questions were analyzed: (1) Are wetland altitude, area, habitat diversity, hydroperiod (permanent and intermittent), ecoregion, and macroinvertebrate richness good predictors of occurrence, richness, abundance and composition of fish species? and (2) Are the predictors of fish richness similarly applicable to different ecoregions in Southern Brazil? Our data showed that fish richness was related to habitat diversity and macroinvertebrate richness, and fish occurrence was influenced by wetland area and macroinvertebrate richness. Fish abundance was influenced by altitude, hydroperiod and macroinvertebrate richness, and the fish composition was jointly associated with ecoregion, and hydroperiod. The predictors of fish richness were not similarly applicable to different ecoregions. Our results showed that the habitat diversity, macroinvertebrate richness, altitude and hydroperiod were the environmental predictors that potentially structure and maintain the fish occurrence and richness in southern Brazil palustrine wetlands. Such information is essential to develop wetland conservation and management programs in this region, where more than 90 % of wetland systems have already been lost and the remaining ones are still at high risk due to the anthropogenic activities.

Community Based Assessment of Biochemical Risk Factors for Cardiovascular Diseases in Rural and Tribal Area of Himalayan Region, India

Context. Evident change in nutrition and lifestyle among individuals of urban and rural areas raises suspicion for similar change in tribal area population of India. Aim. To study the biochemical risk factor for CVDs in rural and tribal population of Sub-Himalayan state of India. Settings and Design. Cross-sectional study in rural (low altitude) and tribal (high altitude) area of Himachal Pradesh, India. Methodology. Blood lipid profile using standard laboratory methods. Statistical Analysis. Chi-square test and multiple linear regression analysis. Results. Total of 900 individuals were studied in both areas. As per Asian criteria, obesity (BMI 27.5–30.0 kg/m2) was observed to be significantly high (P = 0.00) as 13.7% in tribal area as compared to 5.5% in rural area. Normal level of TC (<200 mg/dL) and LDL (<130 mg/dL) was observed in the majority of the population of both areas, whereas, at risk level of HDL (<40 mg/dL) was present in half of the population of both rural and tribal areas. The prevalence of borderline to high level of TGs was observed to be 60.2% and 55.2% in rural and tribal (P = 0.10) area, respectively. Conclusion. Prevalent abnormal lipid profile in tribal area demands establishment of an effective surveillance system for development of chronic diseases.

Erythrina velutina willd. (Leguminosae-Papilionoideae) ocorrente em caatinga e brejo de altitude de Pernambuco: biometria, embebição e germinação

O objetivo deste trabalho foi comparar a biometria de frutos e sementes, a embebição e germinação de duas populações de Erythrina velutina coletadas na região semiárida do Estado de Pernambuco, nas áreas de caatinga (Alagoinha) e no brejo de altitude (Poção). Os frutos e as sementes foram avaliados quanto ao comprimento, largura, espessura (cm) e peso (g). Com relação às sementes, foram analisados o número por fruto, o volume (cm³) e a embebição, bem como a germinação com e sem escarificação mecânica, na presença constante de luz a 25 ºC. Os frutos e sementes do brejo apresentaram os valores assim discriminados: 9,65 x 1,57 x 1,22 cm, 1,43 g e 1,34 x 0,92 x 0,78 cm, 0,46 g; e na caatinga: 6,85 x 1,19 x 1,03 cm, 0,21 g e 1,06 x 0,63 x 0,63 cm e 0,26 g. O número de sementes e o volume no brejo e caatinga foram de 2,33 e 1,38 cm³ e 1,40 e 0,23 cm³, respectivamente. Todas as sementes escarificadas apresentaram maiores valores de embebição e porcentagem de germinação. Quanto à velocidade de germinação, foi maior na caatinga. Esses resultados indicam que as condições ambientais do brejo de altitude favorecem o desenvolvimento dos frutos e das sementes.

Editorial Comment

The etiology and treatment of nonbacterial chronic prostatitis (CP) and chronic pelvic pain syndrome (CPPS) remains an enigma. Numerous causes and treatment options have been postulated, including infection, neurologic, immune factors, and voiding dysfunction. Psychosomatic illness has been advocated. 1 Berberich H.J. Ludwig M. [Psychosomatic aspects of the chronic pelvic pain syndrome]. Urologe A. 2004; 43: 254-260 Crossref PubMed Scopus (12) Google Scholar Influence of Environmental Factors on Prevalence, Symptoms, and Pathologic Process of Chronic Prostatitis/Chronic Pelvic Pain Syndrome in Northwest ChinaUrologyVol. 78Issue 5PreviewTo compare the prevalence, symptoms, and pathologic changes related to chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) with significant prostatitis-like symptoms between 2 altitude areas in northwest China. Full-Text PDF ReplyUrologyVol. 78Issue 5PreviewWe appreciate the opportunity to reply to the Editorial Comment regarding our investigation, in which we sought to relate environmental factors namely domicile in high altitude as a potential stimulant for chronic prostatitis (CP)/chronic pelvic pain syndrome (CPPS). Full-Text PDF

DNA sequence characterisation and phylogeography of Lymnaea cousini and related species, vectors of fascioliasis in northern Andean countries, with description of L. meridensis n. sp. (Gastropoda: Lymnaeidae)

BackgroundLivestock fascioliasis is a problem throughout Ecuador, Colombia and Venezuela, mainly in Andean areas where the disease also appears to affect humans. Transmission patterns and epidemiological scenarios of liver fluke infection have shown to differ according to the lymnaeid vector snail species involved. These Andean countries present the vectors Lymnaea cousini, L. bogotensis and L. ubaquensis, unknown in the rest of Latin America. An exhaustive combined haplotype study of these species is performed by means of DNA sequencing of the nuclear ribosomal 18S RNA gene, ITS-2 and ITS-1, and mitochondrial DNA cox1 gene.ResultsThe conserved 5.8S rDNA sequence corroborated that no pseudogenes are involved in the numerous non-microsatellite/minisatellite-related indels appearing between the ITS-2 and ITS-1 sequences when comparing different L. cousini - L. bogotensis populations. Sequence analyses and phylogenetic reconstruction methods including other lymnaeid vector species show that (i) L. bogotensis is a synonym of L. cousini, (ii) L. ubaquensis is a synonym of Pseudosuccinea columella, and (iii) populations of L. cousini hitherto known from Venezuelan highlands indeed belong to a new species for which the name L. meridensis n. sp. is proposed. This new species is described and a complete phenotypic differentiation provided.ConclusionsITS-2, ITS-1 and cox1 prove to be good markers for specimen classification and haplotype characterisation of these morphologically similar lymnaeids in endemic areas. Analysis of the 18S gene and phylogenetic reconstructions indicate that L. cousini and L. meridensis n. sp. cluster in an evolutionary line different from the one of P. columella, despite their external resemblance. This suggests an evolutionary phenotypic convergence related to similar environments and which has given rise to frequent specimen misclassification. Body size and phylogenetic relationships of L. meridensis n. sp. with well-known vectors as Lymnaea cousini and P. columella, as well as with Galba/Fossaria species, suggest that the new species may participate in disease transmission to both animals and humans in altitude areas during the yearly window in which temperatures are higher than the F. hepatica minimum development threshold. The involvement of L. cousini and P. columella in the transmission and geographical/altitudinal distribution of fascioliasis in these Andean countries is analysed.

Influence of low atmospheric pressure on AC pollution flashover performance of various types of insulators

The electrical performance of outdoor insulators decreases under low air pressure conditions. The ac pollution flashover performance of various types of insulators are investigated in the multifunction artificial climate chamber in the State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University. The field investigation of the ac pollution flashover voltage performance are carried out at three different high altitudes including Wangkun station (altitude of 4484 m), Nachitai station (altitude of 3575 m) along the Qingzang railway and Geermu urban (altitude of 2820 m). The test results indicate that the characteristic exponent n describing the influence degree of air pressure on pollution flashover voltage, which has influence on the pollution flashover voltage of insulators, is variable, and the value of n is related to the pollution, insulator type etc. Under ac voltage, n is 0.45-0.85. The composite insulators are superior in external insulation selection in high altitude and heavy polluted areas. The relative error between the field test results and laboratory test results is less than 8%, so the research results obtained in the laboratory can be applied to engineering design.

Identifying key environmental factors related to plant and crustacean assemblages in Mediterranean temporary ponds

The current interest in Mediterranean temporary wet habitats, considered to be habitats of European Community Interest, is mainly due to their characteristic flora and fauna. Several contributions characterize each of these two components separately, but considering them simultaneously could reveal possible interactions and a more complete view of the habitat that would be useful to improve conservation measures. This paper investigates crustacean and plant assemblages in six Mediterranean temporary ponds and their relationship with several environmental variables. Significant positive relationships were found between species richness and Shannon diversity index of plant and crustacean assemblages. Crustaceans had a higher similarity among ponds than plants and, consequently, each pond had a more characteristic assemblage of plants than of crustaceans. The two groups showed a different sensitivity to environmental factors and only two factors affected both: altitude and surface area of the wet system. Disturbances (e.g. grazing by cattle) and pond size were very important for plants, whereas they were irrelevant for crustaceans. On the other hand, distance to the nearest pond, hydroperiod length, and water nitrogen were only important for crustaceans. Although similar trends on richness and diversity were observed for both biotic groups, the use of only one of them for conservation programs would not be sufficient. Our results suggest that simultaneously taking into account several community components would result in a better understanding of ecosystem functionality.

The dynamic changing profiles of peripheral white blood cell telomere length in populations of different ages living at different altitude areas

To investigate the relationship between the length of telomere DNA and age at different altitude areas. All 172 peripheral blood samples were randomly selected from healthy individuals of different ages from 25 to 65 years old. High altitude group (47 males, 48 females) living at an altitude of 4380 m (HA group), sea level group (39 males, 38 females) living at an altitude of 43 m (SL group). The terminal restriction fragment (TRF) length of telomere DNA was measured by Southern blotting analysis. The plasma levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were assayed. Average TRF lengths of males and females in HA groups were 10.45 +/- 1.35 and 10.50 +/- 1.45. Average TRF lengths of males and females in SL groups were 11.29 +/- 1.10 and 11.31 +/- 1.13. A negative correlation was shown between the average TRF length and age of males in two groups (P < 0.01). This was also the case for females. ANOVA test was used to analyze the difference between TRF length and gender at different ages (P < 0.001). It was shown that there was significant difference in TRF length between the male (25 years old and 55 years old) and female (25 years old and 55 years old) in two groups at different ages (P < 0.05). The plasma levels of SOD and MDA were significant different between HA groups and SL groups (25-44 years old groups/45-65 years old groups) (P < 0.05). Obviously shortening of telomere was observed by increasing of ages in high altitude groups. There was a negative correlation between the length of telomere DNA and ages. Telomere shortening became more obviously in high altitude group than in sea level group in keeping with the age increases.

DETERMINAÇÃO DE LOCAIS ÓTIMOS PARA IMPLANTAÇÃO DE TORRES DE VIGILÂNCIA PARA DETECÇÃO DE INCÊNDIOS FLORESTAIS POR MEIO DE SISTEMA DE INFORMAÇÕES GEOGRÁFICAS

Este artigo teve como objetivo descrever as etapas para a determinação de regiões ótimas para a implantação de torres de vigilância para detecção de incêndios florestais utilizando-se um Sistema de Informações Geográficas (SIG). A área de estudo situa-se na região de Telêmaco Borba (PR). A escolha dos locais das torres de vigilância dependeu da identificação de fatores relacionados ao comportamento humano, identificados neste artigo como ameaça, e no conhecimento da vulnerabilidade do ambiente. A identificação desses fatores conduziu à elaboração de um mapa de risco de incêndio, utilizado como referência para a escolha dos locais de implantação das torres. As variáveis relacionadas à distância entre as torres e seu posicionamento em áreas de maior altitude também foram analisadas. A metodologia proposta levou a uma melhoria na cobertura de visibilidade, aumentando-se a área visível pelas torres em 13.375 ha. Nas regiões identificadas com risco de incêndio alto a elevado, o aumento da visibilidade pelas torres foi de 5.935 ha, correspondendo a 44,37 % da área que se tornou visível.

Holocene environmental history in northwest Finnish Lapland reflected in the multi-proxy record of a small subarctic lake

A 2.5-m-long sediment core was retrieved from Lake Somaslampi, a small lake located in a kame field on the north slope of the Scandes Mountains in Finnish Lapland. Holocene environmental changes were inferred from the lithological, geochemical, pollen, diatom and Cladocera records stored in the lake sediment. The chronology was based on six radiocarbon AMS dates supported by a palynological control chronology. The sediment profile consists of a glacial sedimentary sequence truncated by a lacustrine one. A hiatus, tentatively correlated with climate cooling and advances of glaciers during the 8.2 ka yrs BP “Finse cooling Event”, occurs between these sequences. The glacial sequence was composed of fluvioglacial clastics, smoothly changing into glacio-lacustrine diatomaceous ooze deposited in a meromictic proglacial lake that covered the kame field. The meromixis was probably caused by the greater depth of the lake, the extended ice-cover, and the microbial mats covering large areas of the lake bottom. A distinct change in the biota of the glacio-lacustrine sediments indicates higher trophic conditions than during deposition of the fluvioglacial clastics. The late-Pleistocene vegetation was characterised by subarctic birch tundra vegetation (Betula–Salix–Ericaceae) with low biodiversity gradually changing to Betula–Pinus dominance in the early Holocene. The lake was deep and had a diatom inferred pH ~ 7 indicated also by the dominance of planktonic Cladocera. The base of the lacustrine sediment sequence (6,650–6,300 cal. BP) consisted of loess-rich sediment indicating an increase in eolian activity. This is also supported by the pollen record, which is dominated by more long-distant taxa such as Alnus and Pinus, and by the increased C/N ratio of the sediment. After the initial meromictic phase of the lake, an abrupt lowering of the water level occurred. Lake Somaslampi was isolated from the larger Pre-Lake Somas basin and became holomictic, shallow, much warmer and more productive, until the deterioration of climate around 3,000 yr BP and the increased input of clastics from the tundra soils. The vegetation followed the general climatic trend by gradually changing from the dominance of Betula and Pinus to the dominance of more tundra-related vegetation like Poaceae and Cyperaceae. However, the higher frequencies of planktonic Cladocera and centric diatoms in the most recent sediments indicates higher trophic conditions, increased turbulence and a prolonged ice-free period, which can possibly be linked to the recent climate warming especially in areas of higher altitude and latitude.

Effects of high air temperatures on milk efficiency in dairy cows

26 herds with 71 586 individual records were used. We tested a hypothesis that milk efficiency was influenced by the elevation of the farm, housing system, breed, area of altitude, and by the cooling of dairy cows. There were 20 herds from lowlands and 6 herds from mountains, 20 herds from free-stall housing, 6 herds from tie-stall housing. 8 herds consisted of Slovakian Pied cattle, 4 herds of Red Holstein cattle, 11 herds of Black-Pied Lowland cattle and 3 herds of Slovakian Pinzgau cattle. The herds were divided into 4 groups according to the nearest meteorological station, and they were distributed according to the type of cooling. 10 herds were cooled by misting, 16 herds by fans. We recorded from 96 to 117 summer days and from 49 to 63 tropical days in lowlands for this summer period. Ninety days with temperature-humidity index (THI) above 72.0 were found in the lowest-elevation area. During 55 days we recorded the values higher than 78.0. Production of milk was higher in lowlands than in mountains (8 761.4 kg vs. 6 372.0 kg; P &amp;lt; 0.01). Differences were also recorded in the evaluation of fat and protein production (346.0&amp;nbsp;kg vs. 275.9 kg; P &amp;lt; 0.01; 282.6 kg vs. 205.9 kg; P &amp;lt; 0.001). Milk and protein production was higher in free-stall housing than in tie-stall housing (8 656.3 kg vs. 6 722.1 kg; P &amp;lt; 0.05; 278.7 kg vs. 218.9 kg; P &amp;lt; 0.05). The highest milk production was recorded in Black-Pied Lowland cattle (8 832.7 kg) and the lowest in dairy cows of Slovakian Pinzgau cattle (6 058.0 kg). The mist cooling of dairy cows increased (P &amp;lt; 0.05) the amount of produced milk and protein (9 234.4 kg vs. 7 569.7 kg; 293.5 kg vs. 247.1 kg). &amp;nbsp;