Influence of diet on the rumen protozoal fauna of indigenous African wild ruminants

A study was carried out to determine if the protozoal fauna of indigenous African wild ruminants was different from that found in their domestic counterparts and if the animal's diet influenced the number and types of protozoa. Samples of rumen contents were collected in 1997 and 2001 from various indigenous African wild ruminants in Kenya. All three ruminant feeding types were sampled: browsers or concentrate selectors (giraffe and Guenther's dik-dik); intermediate or adaptable mixed feeders (impala, Thomson's gazelle, Grant's gazelle and eland); grass or roughage eaters (hartebeest and wildebeest). Total concentration of ciliate protozoa and percentage generic distribution were determined. In general, protozoal concentrations were higher in concentrate selectors, followed by the intermediate or opportunistic mixed feeders and lowest in the grass and roughage eaters. Both Thomson's and Grant's gazelle were protozoa-free in the 2001 samples. Entodinium percentages were considerably higher in concentrate selectors and intermediate mixed feeders, compared to roughage eaters. Two genera of protozoa previously found in only a few African ruminants, Epiplastron and Opisthotrichum, were observed in several additional animal species and represent new host records. A difference was noted in the protozoal species composition of the indigenous wild ruminants from that previously observed in African domestic ruminants.     

The biomass of game animals in Nairobi National Park, 1960–66

The large animals of Nairobi National Park have been censused intermittently once a month from mid-1960 until the end of 1966. Of the 23 species discussed, the density per kilometre has been determined accurately for the following: Grant's gazelle, Thomson's gazelle, water-buck, impala, wildebeest, hartebeest, eland, buffalo, warthog, giraffe, zebra and ostrich. From these figures the biomass has been calculated for each species each year. After a peak biomass of 12,775 kg/sq. km during the drought of 1960–61 the population declined to and remained fairly level at about 5690 kg/sq. km from 1962 to 1966. This figure includes about 1050 kg/sq. km of cattle and sheep. The large predators account for only about 1.4 % of the total biomass of wild animals while removing about 15.5% from this group annually.     

Does competition or facilitation regulate migrant ungulate populations in the Serengeti? A test of hypotheses

Summary Interspecific competition and facilitation have both been proposed as processes promoting species separation and co-existence in African ungulates. In one group of grazers on the Serengeti plains, comprising wildebeest (Connochaetes taurinus), zebra (Equus burchelli), and Thomson's gazelle (Gazella thomsoni), these processes have also been suggested to regulate the populations. Censuses of these populations over 20 years have shown changes that allow a test of which, if either, process regulates population numbers. Wildebeest numbers have levelled off as a result of intraspecific competition for food following a five-fold increase due to release from disease and an increase in food supply. Zebra numbers have remained stationary throughout the same period. Gazelle numbers have declined in the last 10 years. These results are contrary to the facilitation hypothesis, which predicts that wildebeest numbers should not have increased if those of zebra did not, and that gazelle numbers should have increased since the wildebeest population increased. The gazelle results are consistent with the interspecific competition hypothesis, but the zebra results are contrary to it. We propose an alternative hypothesis that predation regulates the zebra population, and we suggest ways of testing this.     

Nutritional estimate of populations of some wild free-ranging African ungulates in grassland (Nechisar national park, Ethiopia) in dry season

The amount and nutritive value of forage plants, diet composition, digestibility of dry matter and nutrients were recorded for zebra. Grant's gazelle, Swayne's hartebeest and hippopotamus in November-December 1991 Besides, daily egest of feces, the level of food and nutrient consumption, energy and protein requirements were recorded for zebra and Grant's gazelle The digestibility of pasture forage was determined as a ratio of lignin concentration in food to the concentration m feces (lignin tracer technique), a daily intake was calculated on the basis of the daily feces egest Protein percentage m the diet of zebra and hartebeest consuming dry parts of grasses did not exceed 5% Gazelle diet consists of green parts of plants and included 18% of protein The digestibility of dry matter in nonruminants (zebra, hippopotamus) was 40-45%, in hartebeest - 50%, in gazelle - 60% Due to the abundance of dry grasses (3 7 ton ha^-1) the daily food consumption of zebra was high - 7 2 kg ind^-1 (dry weight), the metabolizable energy intake (ME) being 51 MJ Adult gazelles consumed 15-25 kg ind^-1 of food and 14-24 MJ of ME The energy requirements of adult males and non-lactating females of zebras and gazelles (48 and 13 MJ respectively) were met, the energy balance berig negative for lactating animals The daily protein requirement was not met in zebra (392-704 g md^-1 vs 134 g ind^-1 of intake) and in lactating gazelles (250 g ind^-1 vs 197 g md^-1) Non-lactating gazelles consume sufficient amount of both energy and protein due to the high feeding selectivity of the species and thanks to the abundance of burnt areas with young green after-grass m the dry period     

Phylogenetic analysis of the microbial populations in the wild herbivore gastrointestinal tract: insights into an unexplored niche

At present, there is little information on the phylogenetic diversity of microbial species that inhabit the gastrointestinal tracts of wildlife. To increase understanding in this area, we initiated a characterization of the bacterial diversity in the digestive tracts of three wild African ruminant species namely eland (Taurotragus oryx), Thompson's gazelle (Gazella rufifrons) and Grant's gazelle (Gazella granti), together with a domesticated ruminant species, zebu cattle (Bos indicus), and a non-ruminant species, zebra (Equus quagga). Bacterial diversity was analysed by PCR amplification, sequencing and phylogenetic analysis of 16S ribosomal DNA (rDNA) sequences. A total of 252 full-length 16S rDNA sequences averaging 1,500 base pairs (bp) in length, and an additional 27 partial sequences were obtained and subject to phylogenetic analysis. Using a 98% criterion for similarity, all except for one of the sequences were derived from distinct phylotypes. At least 24 distinct operational taxonomic units (OTU's) could be identified, with the majority of these sequences representing hitherto uncharacterized species and genera. The sequences were generally affiliated with four major bacterial phyla, the majority being members of the Firmicutes (low G+C Gram-positives) related to the genera Clostridium and Ruminococcus. By contrast, with earlier studies using 16S rDNA sequences to assess biodiversity in Bos taurus dairy cattle, Gram-negative bacteria in the Bacteroidales (Prevotella-Bacteroides group) were poorly represented. The lack of redundancy in the 16S rDNA dataset from the five African ungulate species, and the presence of novel sequences not previously described from the gastrointestinal tract of any animal species, highlights the level of diversity that exists in these ecosystems and raises the question as to the functional role of these species in the gastrointestinal tract.     

Interactions among host diet, nutritional status and gastrointestinal parasite infection in wild bovids

In this study, I explored the interactions among host diet, nutritional status and gastrointestinal parasitism in wild bovids by examining temporal patterns of nematode faecal egg shedding in species with different diet types during a drought and non-drought year. Study species included three grass and roughage feeders (buffalo, hartebeest, waterbuck), four mixed or intermediate feeders (eland, Grant's gazelle, impala, Thomson's gazelle) and two concentrate selectors (dik-dik, klipspringer). Six out of the nine focal species had higher mean faecal egg counts in the drought year compared to the normal year, and over the course of the dry year, monthly faecal egg counts were correlated with drought intensity in four species with low-quality diets, but no such relationship was found for species with high-quality diets. Comparisons of dietary crude protein and faecal egg count in impala showed that during the dry season, individuals with high faecal egg counts (> or =1550 eggs/g of faeces) had significantly lower crude protein levels than individuals with low (0-500 eggs/g) or moderate (550-1500 eggs/g) egg counts. These results suggest that under drought conditions, species unable to maintain adequate nutrition, mainly low-quality feeders, are less able to cope with gastrointestinal parasite infections. In particular, during dry periods, reduced protein intake seems to be associated with declining resilience and resistance to infection.     

Does competition regulate ungulate populations? Further evidence from Serengeti,Tanzania

Summary Changes in populations of several ungulate species in the Serengeti-Mara region of East Africa over the past 30 years suggest several hypotheses for their regulation and coexistence. Recent censuses in the 1980s have allowed us to test the hypotheses that: (1) there was competition between wildebeest (Connochaetes taurinus) and Thomson's gazelle (Gazella thomsoni). This predicted that gazelle numbers should have declined in the 1980s when wildebeest were food limited. Census figures show no change in gazelle numbers between 1978 and 1986, a result contrary to the interspecific competition hypothesis; (2) wildebeest and African buffalo (Syncerus caffer) populations were regulated by intraspecific competition for food. Since both populations reached food limitation in the 1970s, the hypothesis predicted that the populations should have been stable in the 1980s. The results confirm these predictions for wildebeest and the buffalo population in the Mara reserve. In the Serengeti the buffalo population declined 41% over the period 1976–1984. The decline was not evenly distributed over the park, some areas showing an 80–90% decline, others no change or an increase in numbers. The decline was associated with proximity to human habitation; (3) an outbreak of the viral disease, rinderpest, in 1982 may have been the cause of the drop in buffalo population. Blood serum samples to measure the prevalence of antibodies were collected from areas of decreasing, stable and increasing populations. If rinderpest was the cause of decrease there should be a negative relationship between the prevalence of rinderpest and the instantaneous rate of increase (r). The results showed no relationship. We conclude that rinderpest was not the major cause of the drop in buffalo numbers. Elephant (Loxodonta africana) numbers dropped 81% in Serengeti in the period 1977–1986. In the Mara there was little change. The evidence suggests that extensive poaching in northern and western Serengeti during 1979–1984 accounted for the drop in both elephant and buffalo numbers.     

Comparative aspects of muscle fibre size and succinic dehydrogenase distribution in the longissimus dorsi muscle of several species of East African mammals

The distribution of succinic dehydrogenase enzyme activity was investigated in frozen sections of longissimus dorsi muscle taken from several species of East African game animal (giraffe, hartebeest, wildebeest, oryx, gerenuk and dik-dik) as well as local zebu cattle. Muscle fibres were classified as red (high succinic dehydrogenase activity), white (low activity) or intermediate. The mean diameter and percentage distribution of each fibre type were noted as well as the overall mean muscle fibre diameter (MFD) for each species. The diameters of red muscle fibres were found to be between 54 and 62% of the diameters of the white muscle fibres for all species with MFD differences between species being up to over 100%. The variation in MFD was found to be significantly and positively correlated with live weight, when zebu values were omitted. It was found that the variation in MFD was significantly related to the diameter of muscle fibre types and not to the percent distribution of these fibre types.     

Anti-Trypanosoma brucei activity of nonprimate zoo sera

Constitutive anti-Trypanosoma brucei subsp. brucei S 427 clone 1 and 22 activities were evaluated in sera from 22 species of nonprimate mammals. The sera fell into 5 categories. Sera from Cape buffalo, giraffe, and greater kudu showed a concentration-dependent inhibition of replication of the 2 clones of organisms, which was dependent on the presence of xanthine oxidase. Sera from warthog and springbok also severely limited trypanosome replication but lacked xanthine oxidase. Their antitrypanosome activity was inactivated by heating at 56 C for 30 min but not affected by absorbing with trypanosomes at 4 C. Sera from lion and leopard showed a concentration-dependent inhibition of the growth of T. brucei S427 clone 1 organisms, but not clone 22 organisms. These sera lacked xanthine oxidase. Their anti-T. brucei S 427 clone 1 activity was inactivated by heating at 56 C for 30 min but not removed by absorbing with trypanosomes. Serum from Grant's gazelle prevented replication of both T. brucei clones, lacked xanthine oxidase, and was not affected by heating at 56 C. Sera from waterbuck, Thompson's gazelle, sitatunga, Cape hartebeeste, gerenuk, Grant's zebra, cow, several cat, cougar, bobcat, and domestic cat were fully supportive of trypanosome replication irrespective of concentration tested up to a maximum of 48% v/v in culture medium. Sera from different individuals of the same mammal species had similar effects on trypanosomes, and samples collected from the same individual at different times also had similar activities indicating species-specific stable expression, or lack thereof, of constitutive serum antitrypanosome components.     

Body size and the division of niche space: food and predation differentially shape the distribution of Serengeti grazers

1. Theory predicts that small grazers are regulated by the digestive quality of grass, while large grazers extract sufficient nutrients from low-quality forage and are regulated by its abundance instead. In addition, predation potentially affects populations of small grazers more than large grazers, because predators have difficulty capturing and handling large prey. 2. We analyse the spatial distribution of five grazer species of different body size in relation to gradients of food availability and predation risk. Specifically, we investigate how the quality of grass, the abundance of grass biomass and the associated risks of predation affect the habitat use of small, intermediate and large savanna grazers at a landscape level. 3. Resource selection functions of five mammalian grazer species surveyed over a 21-year period in Serengeti are calculated using logistic regressions. Variables included in the analyses are grass nitrogen, rainfall, topographic wetness index, woody cover, drainage lines, landscape curvature, water and human habitation. Structural equation modelling (SEM) is used to aggregate predictor variables into 'composites' representing food quality, food abundance and predation risk. Subsequently, SEM is used to investigate species' habitat use, defined as their recurrence in 5 × 5 km cells across repeated censuses. 4. The distribution of small grazers is constrained by predation and food quality, whereas the distribution of large grazers is relatively unconstrained. The distribution of the largest grazer (African buffalo) is primarily associated with forage abundance but not predation risk, while the distributions of the smallest grazers (Thomson's gazelle and Grant's gazelle) are associated with high grass quality and negatively with the risk of predation. The distributions of intermediate sized grazers (Coke's hartebeest and topi) suggest they optimize access to grass biomass of sufficient quality in relatively predator-safe areas. 5. The results illustrate how top-down (vegetation-mediated predation risk) and bottom-up factors (biomass and nutrient content of vegetation) predictably contribute to the division of niche space for herbivores that vary in body size. Furthermore, diverse grazing assemblages are composed of herbivores of many body sizes (rather than similar body sizes), because these herbivores best exploit the resources of different habitat types.     

Use of δ13C values to determine vegetation selectivity in East African herbivores

Summary The quantitative plant species composition of the rumen contents of a large number of individuals from eight East African herbivores was determined by direct visual analysis. All plant species were classified as either C₃ or C₄, and an estimated ₁₃C for the rumen sample was calculated. This estimated value was compared to a measured value determined directly from rumen subsample. The two methods of determining quantitative C₃ and C₄ composition differed by less than 1%, and the isotopic analysis has the advantage of being rapid and totally objective.The isotopic analysis allowed us to differentiate between grazers and browsers and to determine the quantitative dependence of each animal on C₃ and C₄ photosynthetic types. Kongoni, wildebeest, cattle, and sheep were nearly pure grazers on the Athi Kapiti Plains; and the Grant's gazelle were predominantly browsers. Thompson's gazelle, goast and impala were intermediate. The species most dependent upon browse showed a marked and rapid shift to grass within a few days following rain. This isotopic method may have general utility in the study of East African ecology.     

The physiological basis of adaptation in goats to harsh environments

Goat living in harsh environments represents a climax in the capacity of domestic ruminants to adjust to such areas. This ability is multifactorial: low body mass, and low metabolic requirements of goats can be regarded as an important asset to them for it minimise their maintenance and water requirements, in areas where water sources are widely distributed and food sources are limited by their quantity and quality. An ability to reduce metabolism allows goats to survive even after prolonged periods of severe limited food availability. A skillful grazing behaviour and efficient digestive system enable goats to attain maximal food intake and maximal food utilisation in a given condition. There is a positive interaction between the better recycling rate of urea and a better digestion of such food in desert goats. The rumen plays an important role in the evolved adaptations by serving as a huge fermentation vat and water reservoir. The water stored in the rumen is utilised during dehydration, and the rumen serves as a container, which accommodates the ingested water upon rehydration. The rumen, the salivary glands and the kidney coordinately function in the regulation of water intake and water distribution following acute dehydration and rapid rehydration. Goats in the tropics, when possible, eat a diet composed of tree-leaves and shrubs (browse), which ensure a reliable and steady supply of food all year around, albeit, from a low to medium quality food. Some of the physiological features of ruminants defined as intermediate feeders like large salivary gland, the large absorptive area of their rumen epithelium, and the capacity to change rapidly the volume of the foregut in response to environmental changes are most likely responsible for the goat’s superior digestion capacity.     

Evolutionary adaptations of ruminants and their potential relevance for modern production systems

Comparative physiology applies methods established in domestic animal science to a wider variety of species. This can lead to improved insight into evolutionary adaptations of domestic animals, by putting domestic species into a broader context. Examples include the variety of responses to seasonally fluctuating environments, different adaptations to heat and drought, and in particular adaptations to herbivory and various herbivore niches. Herbivores generally face the challenge that a high food intake compromises digestive efficiency (by reducing ingesta retention time and time available for selective feeding and for food comminution), and a variety of digestive strategies have evolved in response. Ruminants are very successful herbivores. They benefit from potential advantages of a forestomach without being constrained in their food intake as much as other foregut fermenters, because of their peculiar reticuloruminal sorting mechanism that retains food requiring further digestion but clears the forestomach of already digested material; the same mechanism also optimises food comminution. Wild ruminants vary widely in the degree to which their rumen contents 'stratify', with little stratification in 'moose-type' ruminants (which are mostly restricted to a browse niche) and a high degree of stratification into gas, particle and fluid layers in 'cattle-type' ruminants (which are more flexible as intermediate feeders and grazers). Yet all ruminants uniformly achieve efficient selective particle retention, suggesting that functions other than particle retention played an important role in the evolution of stratification-enhancing adaptations. One interesting emerging hypothesis is that the high fluid turnover observed in 'cattle-type' ruminants - which is a prerequisite for stratification - is an adaptation that not only leads to a shift of the sorting mechanism from the reticulum to the whole reticulo-rumen, but also optimises the harvest of microbial protein from the forestomach. Although potential benefits of this adaptation have not been quantified, the evidence for convergent evolution toward stratification suggests that they must be substantial. In modern production systems, the main way in which humans influence the efficiency of energy uptake is by manipulating diet quality. Selective breeding for conversion efficiency has resulted in notable differences between wild and domestic animals. With increased knowledge on the relevance of individual factors, that is fluid throughput through the reticulo-rumen, more specific selection parameters for breeding could be defined to increase productivity of domestic ruminants by continuing certain evolutionary trajectories.     

Population trends of large non-migratory wild herbivores and livestock in the Masai Mara ecosystem, Kenya, between 1977 and 1997

The total of all non-migratory wildlife species in the Masai Mara ecosystem has declined by 58% in the last 20 years. This decline ranges from 49% in small brown antelopes to 72% in medium brown antelopes. In individual wildlife species, the decline ranges from 52% in Grant's gazelle to 88% in the warthog. Declines of over 70% have been recorded in buffalo, giraffe, eland and waterbuck. Only elephant, impala and ostrich have not shown any significant decline or increase. Overall, there has not been any significant difference in decline of all wildlife population sizes inside and outside the reserve, except for Thomson's gazelle and warthog. Livestock have not significantly declined over the entire analysis period. However, livestock and cattle populations significantly declined during the 1983–88 period. Donkey declined by 67%, while shoats (goats and sheep) remained stable. In the case of wildlife, land use and vegetation changes, drought effects and poaching are considered to be among the potential factors that may have been responsible for the decline; the decline in livestock during the 1983–84 period was probably due to drought effects.     

The occurrence of infectious diseases in mixed farming of domesticated wild herbivores and livestock in Kenya. II. Bacterial diseases

The prevalence of antibodies to Brucella spp., Mycobacterium paratuberculosis and the Mycoplasma spp. causing contagious bovine pleuropneumonia and contagious caprine pleuropneumonia was determined in various species of ruminants on a ranch in the semi-arid zone of southeastern Kenya. Antibody titers to Brucella spp. were found in eland (Taurotragus oryx), oryx (Oryx beisa) and camels (Camelus dromedarius). Reactors were not found in buffalo (Syncerus caffer), sheep (Ovis aries) and goats (Capra hircus). Brucella sp. was not isolated from eland and camels. Antibody titers to M. paratuberculosis were found only in camels and goats. Mycobacteria were not detected in feces of two serologically positive camels. Significant serum antibody titers to Mycoplasma mycoides mycoides were found only in camels. Antibody titers to Mycoplasma sp. (strain F38), which causes contagious caprine pleuropneumonia, were found in buffalo, cattle and camels but not in the other species. Attempts to isolate the Mycoplasma sp. from nasal secretion of the buffalo and camels failed. The possible occurrence of tuberculosis in camels is discussed. Under the conditions at the ranch, contagious bacterial diseases appear to be of minor importance in the domesticated wild herbivores. The introduced camels, however, might be a source of various infections such as brucellosis, mycoplasmosis and possibly tuberculosis for the other susceptible species.     

Evidence of three new members of malignant catarrhal fever virus group in muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (Oryx gazella)

Six members of the malignant catarrhal fever (MCF) virus group of ruminant rhadinoviruses have been identified to date. Four of these viruses are clearly associated with clinical disease: alcelaphine herpesvirus 1 (AlHV-1) carried by wildebeest (Connochaetes spp.); ovine herpesvirus 2 (OvHV-2), ubiquitous in domestic sheep; caprine herpesvirus 2 (CpHV-2), endemic in domestic goats; and the virus of unknown origin found causing classic MCF in white-tailed deer (Odocoileus virginianus; MCFV-WTD). Using serology and polymerase chain reaction with (degenerate primers targeting a portion of the herpesviral DNA polymerase gene, evidence of three previously unrecognized rhadinoviruses in the MCF virus group was found in muskox (Ovibos moschatus), Nubian ibex (Capra nubiana), and gemsbok (South African oryx, Oryx gazella), respectively. Base on sequence alignment, the viral sequence in the muskox is most closely related to MCFV-WTD (81.5% sequence identity) and that in the Nubian ibex is closest to CpHV-2 (89.3% identity). The viral sequence in the gemsbok is most closely related to AlHV-1 (85.1% identity). No evidence of disease association with these viruses has been found.     

Resource partitioning between sympatric wild and domestic herbivores in the Tarangire region of Tanzania

The effect of the introduction of an exotic species (cattle) into a native African herbivore assemblage was investigated by studying resource partitioning between zebu cattle, wildebeest and zebra. Resource partitioning was investigated by analysing grass sward characteristics (such as sward height and percentage nitrogen in leaves) of feeding sites selected by the different herbivore species. Linear discriminant analysis was used to determine whether a distinction could be made between feeding sites selected by the different animal species or whether the animal species showed overlap in resource use by selecting similar feeding sites. Wildebeest and zebra did not show overlap in resource use except in the wet season when resources were ample. Cattle showed overlap in resource use with zebra in the early wet season and with wildebeest in the early dry season, seasons when food limitation is likely. In the wet season, cattle showed overlap in resource use with both zebra and wildebeest. Implications of these results for competitive relationships between livestock and wildlife are discussed. We suggest that interpretation of overlap in resource use may be different for an assemblage of long-term coexisting native species as compared to an assemblage of native and exotic species. Among native herbivores, overlap in resource use is not expected based on evolutionary segregation. In a native assemblage to which an exotic species has been introduced, however, overlap in resource use can occur under food-limited conditions and consequently implies competition. Received: 1 September 1998 / Accepted: 20 April 1999     

Prevalence of Toxoplasma gondii antibodies in sera of domestic pigs and some wild game species from Zimbabwe

Serum samples of domestic pigs (Sus scrofa), elands (Taurotragus oryx), sable antelopes (Hippotragus niger), warthogs (Phacochoerus aethiopicus), bushpigs (Koiropotamus [Potamochoerus] koiropotamus), white rhinos (Ceratotherium simus), African buffalos (Syncerus caffer), wildebeest (Connochaetas taurinus), and African elephants (Loxodonta africana) from Zimbabwe were tested for Toxoplasma gondii IgG antibodies by the modified agglutination test (MAT) with whole formalized tachyzoites and mercaptoethanol. Sera were diluted at 1:25, 1:50, and 1:500 for MAT testing. Sera with antibodies in a 1:25 dilution were considered to have T. gondii infection. Toxoplasma gondii antibodies were found in 9.3% of 97 domestic pigs, 36.8% of 19 elands, 11.9% of 67 sables, 0 of 3 warthogs, 0 of 3 bushpigs, 50% of 2 white rhinos, 5.6% of 18 buffalos, 14.5% of 69 wildebeest, and 10.5% of 19 elephants examined.     

藏羚羊冷季对干物质的消化效率

藏羚羊（Pantholops hodgsoni）为青藏高原特有物种,也是世界上最为珍贵和稀有的物种之一。作为青藏高原野生食草动物的典型代表,藏羚羊种群也是构成青藏高原自然生态系统极为重要的组成部分。藏羚羊独特的体态和生理结构,对研究生物适应与进化,尤其是研究高原条件下的生物适应与进化,维护高原地区生态平衡均有极为重要的意义（郑中朝和李宏,2002）。对藏羚羊牧草利用特征的研究对其营养生态学的研究具有重要的科学价值。本文采用藏羚羊饲草中酸不溶灰分作为内源指示剂,对其冷季牧草消化率进行了初步研究,现将结果予以报道。