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Fossil bovids are widely recognized as valuable ecological indicators, useful for reconstructing paleoenvironments associated with the hominins of Africa. Taxonomic identification of bovid remains in the Plio-Pleistocene fossil deposits of South Africa is based predominantly on dental remains, usually isolated teeth. However, factors such as age and degree of occlusal attrition of teeth often render taxonomic identification difficult. In addition, teeth of closely related bovid taxa can be particularly difficult to diagnose at the species level. Given that closely related bovid species often have differing ecological requirements, imprecise identification of bovids recovered from fossil sites can have significant ramifications when reconstructing environments. This study tests a method for accurately identifying bovid teeth using Elliptical Fourier Function Analysis in order to standardize their identification. The occlusal surfaces of maxillary and mandibular molars of bovid teeth from twenty extant species were digitized and the quantified tooth forms (size and shape) were statistically compared to other closely related bovids. Results indicated that all upper and lower teeth classified correctly using discriminant function analysis ≥85% of the time, suggesting that occlusal surface form can reliably differentiate between closely related, morphologically similar bovids. This method was applied to a sample of fossil bovid teeth previously identified as “medium-sized alcelaphine” from Plovers Lake, Gauteng Province, South Africa. Precise taxonomic identification of these alcelaphines result in the earliest recorded presence of Alcelaphus buselaphus and Connochaetes gnou in Gauteng Province, as well as potentially the earliest documented co-occurrence of these taxa alongside Connochaetes taurinus and Damaliscus dorcas in South Africa. Revising the paleoenvironment reconstructed for Plovers Lake suggests that it was likely not much more densely wooded than the area today. This contradicts the paleoenvironment previously inferred for the site, suggesting that overreliance on rare and/or small-bodied taxa in the initial report on Plovers Lake overemphasized the extent of woodlands that were indicated.

We determined the effect of region and gender on the physical (pH45min, temperature45min, pH24h, temperature24h, L*-value, a*-value, b*-value, hue-angle, chroma, drip loss, cooking loss and Warner-Bratzler shear force value) and sensory properties (aroma, flavour, initial juiciness, sustained juiciness, first bite and residue) of M. longissimus dorsi from blesbok (Damaliscus dorcas phillipsi). Meat from a total of 65 blesbok (males and females) from four regions (Maria Moroka, Gariep, Qua-Qua and Rustfontein in the Free State Province, South Africa) were evaluated. No gender effects were found in any of the physical characteristics. However, region influenced (P < 0.05) pH45min (mean: 6.17), pH24h (mean: 5.49), temperature24h (mean: 7.39°C), a*-values (mean: 12.90), chroma (mean: 15.73) and cooking loss (mean: 34.63%). Both region and gender had a significant effect on first bite and residue, whereas sustained juiciness was only influenced (P < 0.05) by region. Blesbok presented a meat that would be accep...

Zusammenfassung Die Konzentration einiger Spurenelemente in der Leber vom Blesbok (Damaliscus dorcas phillipsi) und vom Bontebok (Damaliscus dorcas dorcas) bestimmt durch Neutronen-Aktivierungs-Analyse In der Arbeit werden die Gehalte an einigen essentiellen Spurenelementen im Lebergewebe von Damaliscus dorcas phillipsi und Damaliscus dorcas dorcas angegeben. Sie wurden mit Hilfe der Neutronen-Aktivierungs-Analyse oder der High-resolution Gammaspektrometrie bestimmt. Beide Methoden werden genau beschrieben und die geographischen Unterschiede zwischen den Tierpopulationen hervorgehoben.

The variation of daily rhythms were analysed in relation to environmental factors. Activity phases were determined for Przewalski horses (Equus ferus przewalskii), feral domestic horses (Equus caballus), and mouflon (Ovis orientalis musimon) in Europe under semi-natural conditions by storage telemetry (ETHOSYS®) and compared to samples from plain zebra (Equus burchelli) and blesbok (Damaliscus dorcas phillipsi) in South African reserves. The activity phase of Przewalski horses was about 16 h in the afternoon but delayed during the summer months; feral horses showed similar phases with lower variation. Mouflons had phases of about 14 h, delayed until 20 h during summer. Zebra showed activity phases after midnight, in the morning, afternoon, and in the evening, but never around noon. The activity phases of blesbok were found at all times of the day. The high variation under African conditions is discussed as resulting from masking by temperature, drought and predation pressure.

The aim of this study was to describe the chemical composition of blesbok meat as influenced by region and sex. M. longissimus dorsi from both sexes of adult blesbok from different regions (Maria Moroka, Gariep, Qua-Qua and Rustfontein in the Free State Province, South Africa) were measured for chemical composition, cholesterol, fatty acid, amino acid and mineral contents. Sex had no influence on any of the chemical components evaluated. Region had an effect (P

A database of approximately 9000 trophy measurements of ungulates hunted in South Africa between 1993 and 2001 was analysed in order to detect species-specific,regional variation in mean trophy quality. Blesbok (Damaliscus dorcas), eland (Taurotragus oryx), impala (Aepyceros melampus), kudu (Tragelaphus strepsiceros), mountain reedbuck (Redunca fulvorufula) and springbok (Antidorcas marsupialis) showed statistically significant variation in trophy quality. A number of other species including blue wildebeest (Connochaetus taurinus), black wildebeest (Connochaetus gnou), bushbuck (Tragelaphus angusticeps), common reedbuck (Redunca redunca), gemsbok (Oryx gazella), red hartebeest (Alcelaphus buselaphus), nyala (Tragelaphus angasii) and waterbuck (Kobus ellipsiprymnus) were insignificant. The manipulation of trophy quality on ranches is speculated to be the major cause of these significant regional variations. It is recommended that species-specific baselines of trophy quality and associated levels of ‘accept...

A database of approximately 9000 trophy measurements of ungulates hunted in South Africa between 1993 and 2001 was analysed in order to detect monotonic trends in trophy quality over time. In a species-specific analysis, declines were found for impala (Aepyceros melampus), springbok (Antidorcas marsupialis) and mountain reedbuck (Redunca fulvorufula). In an area-specific analysis, a decline was found in the Northern Cape Province. Conversely, blesbok (Damaliscus dorcas phillipsi ) (species-specific) and the Free State Province (area-specific) showed increases in trophy quality. As an economic indicator, the monitoring of trophy quality allows agencies to potentially evaluate the quality and sustainability of their ‘huntable’ ungulate resources.

In species with low levels of sexual size dimorphism, it may be relatively easy to detect the role of natural selection in the evolution of body size. Habitat primary production (HPP) appears to be a key factor in the divergence of size in the hartebeest clade (Alcelaphus spp.), such that subspecies in less productive savannahs are smaller than those in richer ones. Here I test whether a similar pattern exists within the genus Damaliscus (topi and their allies). Basal skull length was used as a surrogate of body size and measured in the seven allopatric subspecies of Damaliscus. Means for each subspecies and sex were regressed against climatic factors as surrogates of HPP. Variation in skull length across Damaliscus taxa was less than in hartebeest. Two clusters were present in both sexes and corresponded to the distinction between the species, Damaliscus dorcas and Damaliscus lunatus. This may reflect differences in productivity between edaphic grasslands, occupied by all D. lunatus, and dry grasslands, occupied by D. dorcas. Mean annual rainfall was the best predictor of body size in males and showed a non-significant positive tendency in females. After accounting for phylogenetic effects, these correlations were both non-significant. Edaphic grasslands might be less dependent on precipitation for primary production because the impeded drainage of their soil prolongs water availability after the end of the rains. Furthermore, they are probably more consistent in productivity across African regions than secondary grasslands and savannah woodlands, which rely on rainfall for grass growth. These properties of edaphic grasslands may explain why size in Damaliscus appears to be less sensitive to variation in rainfall and less variable across subspecies than in Alcelaphus.

An improved understanding of reproductive physiology in nondomestic bovids is necessary for the development of assisted reproductive technologies (ARTs) for use in the conservation of endangered bovids. In this study, epididymal spermatozoa were recovered from blesbok (Damaliscus dorcas phillipsi), African buffalo (Syncerus caffer), springbok (Antidorcas marsupialis), and black wildebeest (Connochaetes gnou) following organized culls in South Africa. Our objectives were 1) to characterize the quality of epididymal spermatozoa, 2) evaluate the effectiveness of a cryopreservation protocol, and 3) compare postthaw sperm longevity (motility, viability, and acrosomal integrity) and functionality in two culture media with two capacitation reagents (caffeine and heparin). Following recovery, spermatozoa were diluted in EQ extender, slow-cooled, and frozen in the presence of 5% glycerol. Thawed spermatozoa were separated on a Percoll gradient and diluted in fertilization media (SOF for fertilization [SOF...

The aims of the study were to determine the body composition of springbok, blesbok and impala and to compare the chemical composition (moisture, protein, fat, ash) of the 9th–10th–11th rib cut samples with that of the carcass. The proportional distribution of protein in the carcass, external (heart, feet and skin) and internal offal (heart, heart fat, liver, lungs and trachea, kidneys, kidney fat, spleen, testis, gastro intestinal tract (GIT) fat, diaphragm, stomachs and intestines) was also determined. The physical composition of all three game species followed the same pattern when expressed as a percentage of empty body weight. Impala had a higher (P

The essential amino acid (EAA) profile of the duodenal digesta and whole empty body of springbok ( Antidorcas marsupialis ), blesbok ( Damaliscus dorcas phillipsi ) and impala ( Aepyceros melampus ) were investigated. Significant differences were found between the whole empty body EAA composition of the three game species, whether protein quantity was taken into account (g AA/100 g crude protein (CP)) or not (expressed as % of lysine). The chemical scores indicated that the four most limiting amino acids (three for impala) in the duodenal digesta for whole empty body growth were: arginine, histidine, threonine, methionine for springbok; methionine, arginine, histidine, lysine for blesbok and methionine, histidine, arginine for impala. Excess levels of amino acids tends to be present in the duodenal digesta of blesbok (isoleucine) and impala (lysine, valine, leucine, threonine, isoleucine, phenylalanine). A similar trend was found in the EAA:Lysine ratios of the whole empty body for the three game species.

In addition to the nine compounds identified in the interdigital secretion of the bontebok, Damaliscus dorcas dorcas, in a previous study, 76 compounds belonging to different compound types, were identified in the interdigital secretions of the bontebok and the blesbok, D. d. phillipsi. These compounds include alkanes, alcohols, aldehydes, ketones, fatty acids, terpenoids, γ-lactones, an isopropyl ester, long-chain hydroxyesters, 2-substituted pyridines, phenols, steroids, and dimethylsulfone. No qualitative differences were found between secretions from the two sexes or from animals from different habitats. Although no attempt was made to correlate territorial behavior or other behavioral phenomena with the qualitative composition of interdigital secretions from individual animals, available information seems to indicate that quantitative differences probably do not have a major semiochemical function. Only two species of bacteria, Bacillus brevis and Planococcus citreus, were found in the interdigital pouches of male and female members of the two subspecies, regardless of the habitat of the animals. B. brevis synthesized, among other unidentified constituents, (Z)-3-penten-2-ol, 2-hexanone, 2-octanone, 2-nonanone, tetradecanoic acid, pentadecanoic acid, heptadecanoic acid, octadecanoic acid, (Z)-9-hexadecenoic acid, and isopropyl hexadecanoate in vitro, while P. citreus produced, among others, the γ-lactones dodecan-4-olide and (Z)-6-dodecen-4-olide, which is one of the major constituents of the interdigital secretions of both subspecies. Some components of the interdigital secretions are not present in the interdigital glandular tissue, and the possibility is discused that these compounds could be produced by microbiological activity in the interdigital pouch.

proportion of polymorphic loci (P) was 3.5% (SD = 1.2%), and mean expected average heterozygosity (He) was 0.9% (SD = 0.25%). The populations separated out by genetic distance in two distinct groups, those from the Cape Province and those from the Orange Free State. There were considerable differences in mean body weight between some sites. No correlation could be detected with level of heterozygosity. Body weight appeared rather to be related to liver mineral levels. In particular the ratio between copper and molybdenium appears important with those animals high in copper and low in molybdenium having a higher body weight.

We used protein gel electrophoresis to study genetic diversity within and between blue wildebeest (Connochaetes taurinus), black wildebeest (C. gnou), red hartebeest (Alcelaphus buselaphus caama) and blesbok (Damaliscus dorcas phillipsi). Twenty-nine protein encoding loci were resolved, average heterozygosity ranged from 3.25-5.36% and between population gene diversity accounted for the major share of the total relative gene diversity (69.34%). Genetic distance values ranged from 0.021 to 0.132 and 0.029 to 0.136, with closest identity between the two wildebeest species (as expected for congeneric species). The results are discussed with specific reference to taxonomic relationships between species within the subfamily where interbreeding is known to have occurred.

Single-crystal40Ar/39Ar age estimates of 392,000 ± 4000 to 330,000 ± 6000 yr from Lainyamok, a middle Pleistocene fossil locality in the southern Kenya rift, document the oldest evidence from sub-Saharan Africa of a diverse, large mammal fauna consisting entirely of extant species. The inferred age of this fauna implies an upper limit for extinction of species that characterize well-calibrated, mid-Pleistocene fossil assemblages in East Africa. For its age and species richness, the Lainyamok fauna is surprising for its lack of extinct forms (e.g., the bovinePelorovis) well documented in later faunal assemblages of East and South Africa. Definitive presence of the South African blesbok(Damaliscus dorcas)is also unexpected, especially as this alcelaphine bovid is the dominant large mammal in the Lainyamok fauna. These age estimates and the faunal composition at Lainyamok indicate that geographic ranges and taxonomic associations of extant largebodied mammals were susceptible to wide fluctuations in sub-Saharan Africa over the past 330,000 yr. This inference is consistent with the hypothesis of nonanalogue, or ephemeral, biotas believed to characterize late Quaternary ecosystems of northern continents.

and 24 August 1997 in Modoc Co.,California.2. Previous workUngulate interdigital glands: bontebok, Damaliscus dorcas dorcas (Burger et al.,1976, 1977); black-tailed deer, Odocoileus hemionus columbianus (Wood et al., 1995a, b);gemsbok, Oryx gazella gazella (Wood, 1997); reindeer, Rangifer tarandus, (Brundinet al., 1978; Andersson et al., 1979); sable antelope, Hippotragus niger (Wood, 1998);white-tail deer, O. virginianus (Gassett et al., 1996; Wood, 1999); wildebeest,Connochaetes taurinus (Wood, 1998).3. Present studyA pronghorn’s interdigital glands were removed from the fore- and hind-feet bydissection and manually palpated to express the unctuous white secretion. The

We applied the method to syntheses of (Z)-5-undecen-2-one, a sex pheromone from the pedal gland exudate of the bontebok (Damaliscus dorcas dorcas), and 1,4-dicarbonyl compounds that are important precursors of 2-cyclopentenone derivatives

Resume Cytogenetic analyses involving G- and C-banded chromosomes from the red hartebeest Alcelaphus buselaphus (2n = 40), the blesbok Damaliscus dorcas (2n = 38) and their hybrids are presented. The diploid number of the hybrids (2n = 39) is consistent with predictions for the F1. The parental species differ in respect of a single fusion; while good banding homology exists between the long arm of the biarmed blesbok marker chromosome and its putative homologue in the red hartebeest, a paracentric inversion appears to have disrupted banding homology between the short arm and the corresponding red hartebeest homologue. Segregational difficulties encountered in the meiosis of hybrids are thought to contribute to sterility, an hypothesis further supported by azoospermia and the paucity of germ cells in seminiferous tubule cross-sections. Our results confirm previously unsubstantiated and anecdotal reports of hybridization between these taxa and, in the broader sense, address issues posed by the translocation of game species, a practice which forms part of current conservation and game marketing strategies.

Rumen contents were collected from ten adult female blesbok, five from a mine area with only acid drinking water available and five from a control group consuming normal, non-polluted drinking water. The mean concentration of total protozoa in the normal water group was almost double that in the acid drinking water group, 24.9 x 103 versus 14.7 x 103 . Percent of Entodinium was higher and Diplodinium lower in those animals drinking the acid water. The number of different protozoa species present in animals from both locations was fairly similar. Diplodinium bubalidis, Ostracodinium gracile and Diplodinium consors were present in the highest percentage in the normal water group, 18.8, 18.4 and 17.7 %, respectively. The same three species, plus Entodinium dubardi, were also highest in the acid water group, O. gracile, 21.3 %; D. consors, 12.6 %; E. dubardi, 11.4 % and D. bubalidis, 10.3 %. Seventeen species of protozoa found in this study were a new host record for the blesbok, bringing the total number of species reported from the blesbok to 29.

The significance of pheromones in olfactory communication in mammals, and the possibility of using synthetic pheromones to influence the behaviour of problem animals, are briefly discussed. The isolation, identification and synthesis of the principal volatile component contained in the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. (Z)-5-undecen-2-one, are reported. Some of the other major constituents of the secretion have been identified as 2-heptanone, 2 -nonanone, 2 -undecanone and 2,5-undecanedione.

The Bontebok is a rare, medium-sized antelope (males weigh 68–86 kg and females about 56 kg) which is restricted in range to the coastal plain of the south western Cape district of South Africa. The largest herd in existence, consisting of about 250 animals, was studied for 15 months in the Bontebok National Park. Mating is seasonal, occurring in January to March. Females are in oestrus for only about 24 hours and will consort with any male during this time but due to the strongly territorial social system will often be restricted to the territory of a single male. Copulation is repeated many times during the oestrus period and is similar to that described for other members of the Bovidae. The social structure consists of territorial males, very small nursery herds of females and young and a bachelor herd of up to 100 males of all ages. Calving is also seasonal and one birth was witnessed. Females remain with the herd during parturition. There is no lying out behaviour and calves follow their mothers from birth. Calves spent 80–90% of their time lying down for the first two weeks of their life and suckle every one to two hours. Calves less than five days old suckle for significantly longer than older calves. Summary Mating and parturition in Bontebok are strongly seasonal and gestation is about eight months. Most adult females with their young spend their time grazing on the territory of a territorial male in small nursery herds. The male pays attention to all females on his territory and addresses his courtship display to each of his females frequently at all seasons of the year. A female comes into oestrus for about 24 hours and will copulate many times with any male during this period though often she may remain on the territory of a single male. The male and the oestrus female may remain slightly apart from the other females in the group during the period of her oestrus. Copulation is very brief and is similar to other bovids, consisting of a single ejaculatory thrust. There is a marked lack of precopulatory or postcopulatory displays by the male and copulation is preceded only by the normal courtship display or by no display at all. Normally there are bouts of sexual activity involving many unsuccessful mountings and a few successful copulations interspersed with longer periods of other activities (e.g. grazing). The territorial system ensures that other males do not interfere with mating. The female calves in the herd and the calf runs with the mother from birth. There is no lying out behaviour. The females eats the foetal membranes but not the placenta which is dropped 4–6 hours later. Calves spend 80–90% of their day lying down during the first two weeks of life but by seven weeks spend 40% of the day grazing. Calves in the age bracket 6–11 days have a total suckling time during the daylight hours of 80–380 seconds. Calves five days old or less suckle for an average 58 seconds per event, while for 6–11 day olds this drops to 24 seconds—statistically a highly significant difference, suggesting a possible critical period for calf survival during its first five days of life. Occasional suckling continues up to the time the calf leaves its mother. Calves of both sexes leave their mothers at the age of about one year. The female pays her offspring little attention after the age of about three weeks and it is up to the calf to stay with its mother. A lost calf utters staccato bleats when looking for its mother.

A description of the early history of the Swellendam district is given. The following aspects of the bontebok Damaliscus dorcas dorcas (Pallas, 1766) are discussed: distribution; origins of the historical confusion between bontebok and blesbok (D. d. phillipsi Harper, 1939); decline of the sub-species; conservation measures and redistribution.

The identification of four further major constituents of the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. α-terpineol, 2-n-heptylpyridine, m-cresol and (Z)-6-dodecen-4-olide and the investigation of the stereochemistry of the double bond in (Z) -6-dodecen-4-olide by means of iterative computer analysis are described. An improved synthesis of this compound is outlined.

The S.A. Lombard Nature Reserve is situated about 12 miles west of Bloemhof, Western Transvaal. The reserve is flat open country with a gentle slope to the east and south. Abandoned alluvial diamond diggings which run from north to south divide the reserve into a western and an eastern area which are geologically different. The region is open grass land with small patches of bush, classified as dry Cymbopogon-Themeda veld. The food habits of black wildebeest Connochaetus gnou, blesbok Damaliscus dorcas phillipsi, Cape eland Taurotragus oryx, Cape oryx Oryx gazella, impala Aepyceros melampus, red hartebeest Alcelaphus buselaphus, and springbok Antidorcas marsupialis were studied over the three year period, 1958 to 1960. All the antelope on this reserve except gemsbok, feed by nibbling the plants here and there, and it was a tedious task to trace the exact feeding spot.

Synthese a partir de la reaction d'aldolisation entre le nitro-1 nonene-3 et l'acetaldehyde

Water turnover in blesbok and impala was studied in the field. Water turnover of the impala was double that of blesbok, this difference was related to crude protein values in the diet. These facts are related to the evolutionary adaptations of the species. Key words: Water turnover, protein intake, impala, blesbok

In rams a positive correlation (P less than 0.001) existed between average testosterone levels from 30-min blood sampling for 18 h and average testosterone levels of samples taken 0, 1 and 2 h after injection of LH-RH administered 90 min after anaesthesia. Attempts were therefore made to assess testosterone status by LH-RH challenge and limited blood sampling in animals immobilized in their natural habitat. In impala (Aepyceros melampus) territorial males had higher plasma testosterone values than did bachelors after LH-RH challenge (8.1 compared with 2.6 ng/ml, P less than 0.05). In blesbok (Damaliscus dorcas), the relationship was less clear, but testicular volume was correlated with plasma testosterone concentration and with testicular responsiveness measured by testosterone produced per unit of LH (P less than 0.001 and P less than 0.05, respectively). The LH-RH challenge technique therefore has value as a measure of testicular function and permits study of ungulates in their natural environment.

Damaliscus dorcas (Pallas, 1766). Misc. Zool., p. 6. TYPE LOCALITY: South Africa, Cape Prov., Caffer Kayls River, between Mussel Bay and Swellendam. DISTRIBUTION: Formerly from S.W. Cape Prov. to E. Transvaal (South Africa); now only in captivity. COMMENT: Includes phillipsi; see Ansell, 1972, Part 15: 55. PROTECTED STATUS: CITES - Appendix II and U.S. ESA - Endangered as D. d. dorcas subspecies only. ISIS NUMBER: 5301419009014001001., Published as part of James H. Honacki, Kenneth E. Kinman & James W. Koeppl, 1982, Order Artiodactyla, pp. 315-343 in Mammal Species of the World (1 st Edition), Lawrence, Kansas, USA :Alien Press, Inc. & The Association of Systematics Collections on page 333, DOI: 10.5281/zenodo.7352976, {"references":["Ansell, W. F. H. 1972. Order Artiodactyla. Part 15. Pp. 1 - 84, in The mammals of Africa: An identification manual (J. Meester and H. W. Setzer, eds.) [issued 2 May 1972]. Smithsonian Institution Press, Washington, D. C., not continuously paginated."]}

Bontebok. Responses of a captive male bontebok Damaliscus dorcas dorcas to secretions of interdigital and preorbital glands were tested by presenting them at a food trough.

Population data for the bontebok Damaliscus dorcas dorcas in the Bontebok National Park are presented. The social structure of the species centres around several breeding herds and a ram herd. Information pertaining to reproduction for the period 1960-1973 is discussed.

During culling operations on blesbok from the Rietvlei Nature Reserve, 198 blood samples were obtained for study of genetic markers including haemoglobins, transferrins, amylases, albumins and carbonic anhydrases. All animals exhibited the same pattern. Blood typing was performed by using goat reagents. These reagents could possibly be used to establish the relationship between the blesbok and the bontebok. Immunoelectrophoresis was used to detect any immunological differences; 123 blesbok samples were tested against antibovine serum prepared in rabbits. The animals could be grouped into four distinguishable types according to the shape and presence of the alpha-2-macroglobulin and the "horizontal55 band.

The use of Azaperone and Fentanyl in the immobiliza- tion of the bontebok (Damaliscus dorcas dorcas) is briefly discussed, and the resulting reactions of the animals to the drugs noted. Measurements of body and horn values are also given for 14 male individuals.

Changes occuring in marrow fat reserves of animals have been used as an indicator of their physical condition (Cheatum, 1949; Riney, 1955). Cheatum correlated his visual estimate with a chemical analysis and Riney used four different condition classes on red deer (Cervus elaphus) for both colour and texture.

The impala exhibits a narrow temperature tolerance, remains active but seeks shade and rests while standing during high ambient temperatures. The blesbok basks to gain body heat, reduces activity by lying during high ambient temperatures and has a lower rate of body water turnover than the impala. Key words: Blesbok, impala, thermoregulation, daily activity, behavior

Methods were devised for collection and analysis of grass samples from African antelope: kudu (Tragelaphus strepsiceros), waterbuck (Kobus ellipsiprymnus), impala (Aepyceros melampus), and blesbok (Damaliscus dorcas). Samples were gathered from the rumen by inserting mechanical fingers through a rumenotomy trocar. A microscope techn*que was developed for the quantitative analysis of grass epidermal fragments. The validity of macroscopic and microscopic approaches for measuring diet was tested experimentally. Trocar samples taken under specified conditions and used for microscopic identification of grass fragments provided an accurate estimation of the frequency of occurrence of grass portions of the rumen contents. J. WILDL. MANAGE. 47(1):70-75 Methods used to determine feeding pref- erences of free-ranging African antelope vary considerably in accuracy and prac- ticability. Fecal analysis (Stewart 1967), frequently used, suffers from disadvantages related to differential digestion of food plants and quantification of the results in terms of the animal's diet. Direct observa- tions of grasses eaten by antelope are diffi- cult to make and to quantify under African field conditions. The analysis of rumen con- tents can provide both qualitative and quan- titative data and seemed worthy of more detailed appraisal. Rumen samples can be collected either from dead animals or from live animals fit- ted with esophageal or rumen fistulas. Shooting animals for rumen collection is seldom feasible in the case of rare species, and fistulation of free-ranging wild animals is impracticable. However, chemical immo- bilization of wild antelope offers a means of temporarily restraining animals for ru

The grazing behaviour and forage preferences of blesbok on the Van Riebeek Nature Reserve near Pretoria are described. Species composition of the grass component of this grassland vegetation as well as its utilization by blesbok were determined by means of point surveys. Blesbok feed exclusively on grasses and show preferences for certain species. Their preferences on burned range differ from those on unburned range. Judging by preference ratings, Themeda triandra and Eragrostis curvula are the most important food plants of blesbok in this Reserve. Rotational burning appears to be essential in the management of blesbok herds kept under such conditions.