Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Antelopes”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1988

Metabolism and evaporative heat loss in the dik-dik antelope (Rhynchotragus kirki).

1. Under controlled conditions, the rate of oxygen consumption (VO2) respiratory frequency, evaporative water loss, heat balance, rectal (Trec) and surface temperatures were determined in the dik-dik antelopes at ambient temperatures (Ta) ranging from 1 to 44 degrees C. 2. The thermal neutral zone was found to be between 24 and 35 degrees C. 3. Respiratory frequency ranged between 27 and 630 breaths/min. 4. At a Ta of 44 degrees C, 95% of the heat produced by the dik-dik was lost via respiratory evaporation. Despite an increase in Trec, cutaneous evaporation did not increase. 5. During panting, VO2 increased in accordance with the expected Q10 effect, contrary to earlier findings. 6. Measurements of circadian rhythm [LD 12:12 (7-19) CT26 degrees C] in VO2 showed that the minimum VO2 (0.42 ml O2/g/hr) occurred at midnight while the maximum (0.78 ml O2/g/hr) occurred at midday. The 24 hr mean VO2 was 0.61 ml O2/g/hr. 7. These measurements suggest that in nature, determinants other than light may be responsible for triggering the variations observed in VO2.

Acclimatization↗
PubMed1988

Studies on renal excretion of potassium in the dik-dik antelope.

1. In a study on the renal handling of potassium by the dik-dik antelope, plasma and urine samples were analysed for potassium, sodium and creatinine concentrations and osmolality during dehydration and intra-ruminal loading of potassium solutions. 2. The fractional excretion of potassium was 0.64 during the control period and rose up to as high as 2.3 during potassium loading. Urinary osmolality and potassium concentration decreased as the urine volume increased but the total amounts of potassium excreted were independent of urine volume. 3. Potassium loading led to a steady increase in its urinary excretion but a decrease in plasma potassium concentration was observed. This observation casts doubt on the hypothesis that alterations in potassium intake produce parallel alterations in plasma potassium concentration (which supposedly stimulates or depresses potassium excretion) and thereby maintain potassium homeostasis. 4. A possible alternative signal for increased potassium excretion following increased intake is discussed.

Animals↗
PubMed1997

Circadian performance of suprachiasmatic nuclei (SCN)-lesioned antelope ground squirrels in a desert enclosure.

Circadian activity parameters of 53 white-tailed antelope ground squirrels, Ammospermophilus leucurus, were measured to determine the role of the suprachiasmatic nuclei (SCN) pacemaker in their health and survival. Wheel-running activity was monitored in the laboratory with 44 individuals to document the presence of free-running circadian rhythms and ability to entrain to light-dark cycles. Twenty-two individuals were returned to the desert site of origin, including 12 intact control animals and 10 animals whose circadian timing had been disrupted by SCN-lesioning. Time of activity was recorded continuously for 15 days in a large outdoor enclosure by a motion detector, a microchip transponder detector, and video surveillance. An unplanned nighttime attack by a feral cat resulted in the death of 60% of the SCN-lesioned animals and 29% of the control animals in the enclosure. Surface activity of SCN-lesioned animals at the food cache occurred both in daytime and at night, ranging from 16.0% nighttime activity for one partially lesioned individual to 52.1% for one completely lesioned animal. Controls were strongly day-active, with nighttime surface trips constituting only 0-1.3% of all excursions to the cache. Nine wild free-ranging individuals, including one with a radiotransmitter collar, were exclusively day-active. One of the functions of the SCN in mammals may be to reduce activity of animals during times that are unfavorable for activity.

Animals↗
PubMed1975

Nutritional studies on East African herbivores. 1. Digestibilities of dry matter , crude fibre and crude protein in antelope, cattle and sheep.

1. A series of digestibility trials was done using four animals of each of the following species: Friesian cattle (Bos taurus), Boran zebu cattle (Bos indicus), Corriedale sheep, fat-tailed sheep, eland (Taurotragus oryx Pallas), Coke's hartebeest (Alcelaphus buselaphus cokei Günther), Thomson's gazelle (Gazella thomsonii Günther) and bush duiker (Sylvicapra grimmia L.). 2. Two batches of pelleted food were prepared from ground maize cobs, cassava, whs (A-E) were prepared containing 65 (A)-135 (E) g crude protein (nitrogen times 6-25)/kg dry matter. The crude-fibre contents of all the diets were similar (120-138 g/kg dry matter). 3. The animals were given the high-protein diet (E), then given diets with decreasing protein contents finishing with the low-protein (A). The antelope and half the sheep were given diets from the first batch of pelleted food, the other four sheep and all the cattle were given diets from the second batch of food. 4. In sheep, there were significant differences in digestibility between the two batches of food. 5. There were no significant differences in the over-all mean digestibilities of all diets when given to cattle (both species) and sheep. However, with diet E, dry-matter digestibility was higher in sheep than in cattle (P smaller than 0-05): the reverse was true with diet A (P smaller than 0-001). Crude-fibre and crude-protein digestibilities followed a similar pattern. The differences between Corriedale and fat-tailed sheep were not significant. The only significant difference between the two species of cattle was the higher digestibility of crude protein in Borans given diet E (P smaller than 0-05). 6. The over-all mean digestibility of the dry matter was higher (P smaller than 0-001) in hartebeest and duiker than in sheep; in Thomson's gazelle (P smaller than 0-01) and eland (P smaller than 0-001) it was lower than in sheep. The values for crude-fibre digestibilities varied in a similar way. 7. The mean apparent digestibility of crude protein was higher (P smaller than 0-001) in eland, hartebeest and duiker than in sheep and gazelle. 8. The results are discussed in relation to the feeding habits and digestive physiology of the various species.

Africa, Eastern↗
PubMed1965

Color vision in the antelope ground squirrel.

Antelope ground squirrels (Citellus leucurus) were able, after conditioning, to respond correctly to a port illuminated with light at a wavelength of 460 nanometers. This color randomly presented at one of two positions, was correctly selected in reference to a second port illuminated with light at 500, 520, 569, and 600 nanometers, or with white light of varying intensity. Luminosity was not a factor in the discrimination.

Animals↗
PubMed2005

Pharmacological properties of N-095, a drug containing red ginseng, polygala root, saffron, antelope horn and aloe wood.

This study sought to establish a pharmacological profile for N-095, a crude drug containing red ginseng, polygala root, saffron, antelope horn and aloe wood. Our studies on rats and mice revealed a number of pharmacological properties of this novel drug. N-095 increased the forced swimming time in mice and prevented gastric ulcers in rats under restraint and water immersion stress conditions at 100 mg/kg or higher. It also prevented footpad swelling in rats treated with lambda-carrageenin and histamine-induced gastric ulcers in rats at 300 mg/kg or higher. Furthermore, N-095 augmented the sedative effect in mice induced by hexobarbital, which is characterized by a decreased spontaneous motor activity and a prolongation of sleeping time. N-095 also stimulated spontaneous contractility of the uterus in rats at 1000 mg/kg and 2000 mg/kg and prevented hemolysis of erythrocytes by heating. In contrast, N-095 had no effect on the respiratory or cardiovascular system or on water and electrolyte regulation in rats or mice. These results show that N-095 is a relatively safe drug for use as a nutrient or tonic.

Animals↗
PubMed1987

Experimental infections of Anaplasma ovis in pronghorn antelope.

Anaplasma ovis was experimentally transmitted from sheep to pronghorn antelope (Antilocapra americana) and back to sheep. Anaplasma ovis was recovered in splenectomized sheep, from two of three spleen-intact pronghorns following their inoculation with blood from known A. ovis carrier sheep. These two pronghorns exhibited a 0.5% or higher A. ovis parasitemia within 48 days after exposure, and an anaplasmosis-positive serological response 91 days after exposure. Clinical signs of illness were not observed. Blood from the infected pronghorns produced disease in four splenectomized sheep.

Agglutination Tests↗
PubMed2005

Physiological acclimation of a desert antelope, Arabian oryx (Oryx leucoryx), to long-term food and water restriction.

Desert mammals often experience scarcity of drinking water and food for prolonged periods. In this study, the first long-term acclimation experiment in a non-domesticated desert-adapted ungulate, we investigated the mechanisms used by the Arabian oryx Oryx leucoryx, to adjust its physiology to progressive food and water restriction over 5 months, an experimental regimen and time course chosen to mimic what it typically experiences between spring and late summer in the desert. At the end of the acclimation period, oryx consumed less than one and half of food and water of animals in the control group and lost 8.2+/-2.6% of their initial body mass. Experimental animals reduced their mass-specific resting metabolic rate (RMR) and total evaporative water loss (TEWL) by 16.2 and 25.7%, respectively, and maintained a digestive efficiency of about 70%. We found no support for the idea that reduced RMR in oryx correlated with a decreased thyroid hormone concentration in plasma. At the end of the 5 months acclimation, oryx continued to mobilize fatty acids to fuel metabolism, and did not use protein breakdown as a major source of gluconeogenesis. Oryx in the experimental group reduced their water intake by 70% and maintained constant plasma osmolality. They adjusted their water budget by reducing mass-specific TEWL, increasing urine osmolality and reducing urine volume by 40%, and excreting feces with <50% water content. Oryx have an unusually low TEWL compared with other arid-zone ungulates; both hydrated and water-deprived individuals have TEWL values, 51.7 and 39.3%, respectively, of allometric predictions for arid-zone ungulates.

Acclimatization↗
PubMed1982

The relationship between rate of oxygen consumption, heart rate and thermal conductance of the dik-dik antelope (Rhynchotragus kirkii) at various ambient temperatures.

1. The extent of cardiovascular adjustments to heat and cold were investigated between ambient temperatures of 5 and 45 degrees C by measuring conductance and the rates of oxygen consumption and heart beats. 2. Minimum heart rate was observed at 25 degrees C (114 +/- 9 beats/min). In the heat at 45 degrees C heart rate was observed to increase only slightly (127 +/- 12 beats/min) but in the cold -5 degrees C heart rate nearly doubled that at 25 degrees C. 3. Thermal conductance was on average 0.031 mlO2 (g. hr. degrees C)-1 below 25 degrees C but increased by more than 20 times at 40 degrees C. 4. A positive correlation between heart rate and rate of oxygen consumption was demonstrated below 25 degrees C and the relation may be of practical use.

Adaptation, Physiological↗
PubMed1984

Basic haematological values in antelopes--III. The Reduncinae and the Antelopinae.

Basic haematological values were measured in 50 individuals of five species falling under the subfamily Reduncinae, including the mountain reedbuck (Reduncula fulvorufula), the eastern waterback (Kobus ellipsiprymnus ellipsiprymnus), the defassa waterbuck (Kobus ellipsipyrmnus defassa), the lechwe waterbuck (Kobus leche) and the Lady Gray's waterbuck (Kobus megaceros) and in 45 animals of three species of the subfamily Antelopinae, including the springbok (Antidorcas marsupialis), the Grant's gazelle (Gazella Granti) and the dama gazelle (gazella dama). The highest mean erythrocyte counts were found in the male springbok: 11.72 X 10(12)/l, the lowest in the lechwe waterbuck: 8.39 X 10(12)/l, the mean haematocrit values varied from 0.538 in the lechwe waterbuck to 0.443 in the defassa waterbuck and the mean haemoglobin content ranged from 181.2 g/l in the male springok to 151.8 g/l in the defassa waterbuck. Leukocyte counts were mostly shown to be in the human range, in the subfamily Reduncinae at the lower limit; only in the mountain reedbuck decreased values of about 3.5 X 10(9)/l were demonstrated. These results are compared with information from the literature and with the normal human range.

Animals↗
PubMed2004

Molecular characterisation and ovine live vaccine 1B evaluation toward a Chlamydophila abortus strain isolated from springbok antelope abortion.

Chlamydiosis is a zoonosis with a worldwide distribution. The reservoir of susceptible hosts is large and includes birds and both domestic and wild mammals. Chlamydial infection, determined serologically, seems to be widespread among wild ruminants in the Paris zoo (France). In February 2003, an abortion case was reported within the springbok (Antidorcas marsupialis) herd of the zoo. PCR assay using primers targeting the polymorph membrane protein gene (pmp) family was performed on both vaginal swab and placenta samples revealing the presence of Chlamydophila. The inoculation into chicken embryos of an infected placenta extract led to the successful isolation of a C. abortus strain referred to as ASb1. The omp1 gene coding the major outer membrane protein (momp) and the 16S-23S rRNA spacer region of ASb1 were compared to those of various strains by restriction fragment length polymorphism (RFLP). The RFLP analysis showed that this isolate belonged to Chlamydophila abortus species and is highly related to known domestic ruminant's strains causing abortion. The efficacy of a live vaccine 1B, based on a temperature-sensitive mutant of the ovine abortion reference strain AB7, was tested. Protection-challenge experiments in a mouse model show that the ASb1 strain led to mice abortions and that vaccination with 1B vaccine provided them with effective protection.

Abortion, Veterinary↗
PubMed2004

A 12-month survey of the gastro-intestinal helminths of antelopes, gazelles and giraffids kept at two zoos in Belgium.

Faecal egg count patterns and clinical signs associated with gastro-intestinal (GI) nematodes of 107 zoo ruminants were monitored at fortnightly intervals for 1 year. The ruminants in this study were kept under different husbandry conditions at two sites of the Royal Zoological Society of Antwerp, the Antwerp Zoo and the Animal Park Planckendael. Artiodactylids involved were Arabian oryx (Oryx leucoryx), scimitar-horned oryx (Oryx dammah), bongos (Tragelaphus euryceros isaaci), sitatungas (Tragelaphus spekii gratus), common eland (Taurotragus oryx), impala (Aepyceros melampus), slender-horned gazelles, (Gazella leptoceros), blue wildebeest (Connochaetes taurinus taurinus), Kordofan giraffes (Giraffe camelopardalis antiquorum) and okapi (Okapia johnstoni). Nematode eggs were recovered from 586 of 1606 (36.5%) individual faecal samples, using flotation techniques. Infection levels were distinctly low at Antwerp Zoo, probably due to zero grazing and daily dung removal. At Planckendael, the herds of Arabian oryx, scimitar-horned oryx and slender-horned gazelles showed markedly higher egg counts than the other herds, with more than 10% of the faecal egg counts having more than 100 eggs per gram (epg) and maximum faecal egg counts of 600, 750 and 1350 epg, respectively. Faecal egg counts increased during the mid-grazing season (July) and peaked at the end of the grazing season (October). No clinical signs, such as loss of faecal consistency, could be correlated with faecal egg counts (P > 0.05). With the exception of significantly more Nematodirus spp. eggs that were present in juvenile eland, no differences in faecal egg counts could be found between the sexes and different age groups. Abomasa and intestines of 17 animals that died during the survey were available for total worm counts. In one Arabian oryx, four slender-horned gazelles and one sitatunga low burdens ranging from 200 to 14,300 were found. Nematode species recovered were Camelostrongylus mentulatus from the abomasa and Trichostrongylus retortaeformis, Nematodirus fillicollis, Capillaria spp. and Trichuris spp. from the intestines. Our findings suggest different nematode infection levels between herds, which are mainly due to husbandry conditions but to a lesser extent to species- or individual susceptibility. Identification of ungulates that are highly infected and knowledge of the seasonal variation of their helminths can contribute greatly to a well-adjusted species-specific management and helminth control program.

Animals↗
PubMed2005

A mitochondrial genome sequence of the Tibetan antelope (Pantholops hodgsonii).

To investigate genetic mechanisms of high altitude adaptations of native mammals on the Tibetan Plateau, we compared mitochondrial sequences of the endangered Pantholops hodgsonii with its lowland distant relatives Ovis aries and Capra hircus, as well as other mammals. The complete mitochondrial genome of P. hodgsonii (16,498 bp) revealed a similar gene order as of other mammals. Because of tandem duplications, the control region of P. hodgsonii mitochondrial genome is shorter than those of O. aries and C. hircus, but longer than those of Bos species. Phylogenetic analysis based on alignments of the entire cytochrome b genes suggested that P. hodgsonii is more closely related to O. aries and C. hircus, rather than to species of the Antilopinae subfamily. The estimated divergence time between P. hodgsonii and O. aries is about 2.25 million years ago. Further analysis on natural selection indicated that the COXI (cytochrome c oxidase subunit I) gene was under positive selection in P. hodgsonii and Bos grunniens. Considering the same climates and environments shared by these two mammalian species, we proposed that the mitochondrial COXI gene is probably relevant for these native mammals to adapt the high altitude environment unique to the Tibetan Plateau.

Amino Acid Sequence↗