Rangeland Research Articles

RANGELAND CONDITION IN PASTORAL AND AGRO-PASTORAL AREAS OF SOUTH-EAST ETHIOPIA: A COMMUNITY KNOWLEDGE-BASED ASSESSMENT

The use indigenous community knowledge in evaluating and sustaining the range land resources has often been overlooked. This paper presents a community knowledge -based assessment undertaken with the objective of assessing the community’s perception towards current rangeland condition and utilization in pastoral and agro-pastoral areas of south east Ethiopia. A multistage sampling method was used where five representative woredas were purposively selected. Peasant Associations (PAs) were stratified into pastoral and agro-pastoral based on their livelihood, and ten PAs were randomly selected from which 5% of the household heads were chosen for interviews. Data were analyzed using SPSS software and descriptive statistics. Results showed that the mean family size in pastoral and agro pastoral areas was 7.71 and 7.32, respectively. Both pastoral and agro-pastoral systems varied (P<0.001) in terms of their livestock ownership. 88.29 % of the respondents from the pastoralists and 68.07 % from the agro-pastoralists responded that natural pasture is the major feed sources for livestock. Feed shortage was the primary challenge to livestock production followed by drought in pastoral and agro pastoral systems, respectively.92.16% and 66. 67% of the respondents in pastoral and agro pastoral categorized the current rangeland condition as poor, respectively, and the driving forces for the change in rangeland condition were indicated as agriculture, over grazing, recurrent drought, bush encroachment and deforestation. In both production systems, range land condition deteriorated due to agricultural expansion, overgrazing, recurrent drought, bush encroachment and deforestation, where the impact of agriculture is more sever in agro pastoral system.

Estimating the Total Volume of Running Water Bodies Using Geographic Information System (GIS): A Case Study of Peshawar Basin (Pakistan)

The main objective of this study is to estimate the changes in land use and land cover in the Peshawar basin, Pakistan, from 2000 to 2020. This will greatly improve the selection of areas designated as the agricultural, industrial, and/or urban sectors of the region and will help in overcoming future problems. With the help of an advanced geographic information system (GIS), land-use and topographic changes were identified. Based on data of the 20 years from 2000 to 2020, the total runoff volume in the Peshawar basin from 2000 to 2010 was calculated to be 13.9 km3 and from 2010 to 2020 was 19.4 km3. This volume estimation will assist in quantifying the total infiltration rate. We inferred that the built-up area increased the most from 2010 to 2020 as compared to other classes. Results showed that from 2000 to 2020, there was a significant increase in urbanization and a significant decrease in vegetation. This study will help the farmer community and environmentalists to manage range land, agricultural land, populations, and water bodies.

Evaluating Potential Impacts of Proposed Industrial Access Road Routes on Wilderness Character in Gates of the Arctic National Park and Preserve, Alaska

Northern Alaska is home to the largest designated wilderness landscape in the United States and among the world’s largest remaining roadless regions. Under the 1980 Alaska National Interest Lands Conservation Act, the Alaska Industrial Development and Export Authority, a semi-public corporation of the state of Alaska, proposed an industrial road to access the Ambler Mining District that would run approximately 320 km along the southern edge of the western Brooks Range, crossing federal, state, and Native Corporation lands. Two alternative routes are being considered that cross the Kobuk Preserve portion of Gates of the Arctic National Park and Preserve, with the northern route running outside of but adjacent to Gates of the Arctic Wilderness. Both Kobuk Preserve and Gates of the Arctic Wilderness are managed by the National Park Service to preserve wilderness character under existing federal law and agency policy. This study evaluates the potential impacts of both routes on wilderness character in the Kobuk Preserve and adjacent Gates of the Arctic Wilderness. We use a hierarchical conceptual framework to identify spatially explicit measures that show the potential impacts of the road on wilderness character. The impacts from each measure are combined using a weighting scheme to generate a series of maps that quantify the potential impacts of these two proposed routes. Our results show that both routes would degrade wilderness character within the Kobuk Preserve, and that the northern route, which is the state’s preferred alternative for the road corridor, would have a significantly greater impact in terms of degrading wilderness character in the adjacent Gates of the Arctic Wilderness.

Ecology of Indigenous Plants in Abandoned Agricultural Areas in Tabuk Region, Saudi Arabia

Due to drought, low soil fertility, little rain fall, elevated levels of evapotranspiration, salinization of the soil and a lack of ground water, the problem of desertion of agricultural areas has developed in KSA in recent years (e.g. Tabuk region). In the Saudi Arabia, agricultural land abandonment’s negative impact on the composition of perennial vegetation, soil quality, and the structure of population was investigated. In the several abandoned fields of the research region, eleven species of perennial plants pertaining to nine families, eleven genera were found. Following the use of the ordination of detrended correspondence analysis (DCA), four plant communities were found. Zygophyllum hamiense, Prosopis farcta, Seidlitzia rosmarinus, Traganum nudatum. The indicators were Pulicaria undulate, Calligonum comosum. Populations of Calligonum comosum and Zygophyllum hamiense were found to be either negatively skewed or inversely J-shaped, indicating fast-growing populations with strong reproductive potential, according to demographic research. Traganum nudatum, Prosopis farcta and S. Rosmarinus, on the other hand, have a nearly symmetrical size-frequency distribution (like a bell in shape). The current research highlights the importance of managing deserted agricultural fields in order to restore and improve range lands having adapted native plants to regional conditions like little water demand.

The role of Mineral Salts Company in pollution of Mighan playa sediments with heavy metals by contamination indices and multivariate analysis methods, Arak, Iran

Heavy metal concentrations were investigated for 30 sediments collected from different regions of Mighan playa/lake. The means of Cr, Cu, Ni, Pb, Zn and Cd in sediments of playa/lake were much lower than the soil guideline values of Iran and background values of region (BVR). However, the maximum concentrations of Cr, Cu, Ni, Pb, Zn and Cd were higher than BVR. Only 7% of Cr, Cu, Zn, 27% of Ni, 14% of Pb and 38% of Cd concentration exceeded the BVR. The heavy metal Cr, Zn, Ni and Cd are the most important metals in different land use. About 11% of the samples in the lake land use contain Cr, Ni, Pb and Zn has concentration higher than BVR. The concentration of Cu and Pb in 33% and 67% samples is exceeded the BVR in Tail of Mineral Salts Company. The spatial distribution patterns of Cr, Cu, Ni, Pb, Zn and Cd were generally similar and increase from Mighan playa/lake to the Arak city and mainly affected by anthropogenic sources. Among the six types of land use, the concentrations of Cr, Ni, Zn and Cd in the range land and wastewater sludge were significantly higher than those in the other land use (p <0.05). In factor analysis, Cr, Ni, Zn in factor1, Cd in factor2, Pb, Zn in factor3 were originated from the municipal sewage, industrial plants activities and Arak urban traffic.

Efficacy of local Bacillus thuringiensis isolates against tomato leaf miner (Tuta absoluta) larvae on tomato plants under screenhouse conditions

Abstract. The negative impact of chemical pesticides on the environment and the increased resistance of tomato leafminer (Tuta absoluta) field populations to chemical pesticides have promoted research on alternative control measures. Biological control with Bacillus thuringiensis (Bt) may be an alternative, especially against larval instars of T. absoluta. A total of five B. thuringiensis strains were isolated from soil sampled from two different Cow range lands in Zaria, Nigeria; and they were screened for the presence of the cry1 genes using polymerase chain reaction. Of the five isolates, two (40%) showed the presence of the cry1 genes. Results of the bioassay conducted against 2nd instar larvae of T. absoluta at 28±2°C indicated that each of the concentrations (25, 50, 75 and 100 ppm) of the spore crystal mixtures derived from the isolates harbouring cry1 genes caused significant mortality to larvae of T. absoluta after 72 hours in comparison to the control (0 ppm). Probit analysis was used to determine the LC50 and LT50 values. When the treatments were assessed at 48 and 72 hours, LC50 values against larvae were 74.1 and 25.3 ppm for isolate F3, while the LT50 values of that same isolate F3 at 100 ppm and 75 ppm were 36.3 and 42.7 hours, respectively. B. thuringiensis strain F2 achieved 68.7% reduction in T. absoluta damage on tomato plants, while B. thuringiensis isolate F3 achieved 71.3% reduction. Therefore, the spore crystal mixture derived from indigenous Bt strains is the candidate to be used for foliar application against T. absoluta and it is recommended into integrated pest control strategies for the management of T. absoluta.

The Effects of Foot and Mouth Disease in Yak and Cattle herds of Rasuwa District due to Climate Change

In the era of Climate Change, the paper spotlights the importance of managing the high-altitude range land management in Nepal’s northern Rasuwa district bordering the Tibetan plateau. It points to the important fact that policies and strategies need to be inclusive and intersectional with gender equality and social inclusion (GESI) as a vital principle of good governance. Such policies, inclusive governance and support to vulnerable transhumance herders will enhance adequate grass and fodder for yak, chauri, sheep and cattle and at the same time provide veterinary support leading to improved livelihoods for the entire communities. Yak herding is carried out by Tamang transhumance community and in the age of climate change; pasture management together with extension support from local government, is critical to provide additional income to the local communities. The paper examines risk factor, i.e., foot and mouth disease (FMD) and vital nutrient requirements in terms of good quality grass fodder. It also examines the role of customary headman called the “Chogo” who collectively with his “local counsel” facilitate, wise use of the region’s natural resources, i.e., water, irrigation, forest, agriculture and above all pasture land and mediates local conflicts.

Spatial Scale Effects of the Relationship between Fractional Vegetation Coverage and Land Surface Temperature in Horqin Sandy Land, North China.

Sandy range land refers to a major component of grassland area types in the semi-arid area of northern China. Monitoring of vegetation and land surface temperature (LST) using remote sensing technology can help determine the degree of desertification in a regional and/or sub regional scale, as in the Horqin Sandy Land selected in this study. Correlation analysis was performed to examine the relationship between the fractional vegetation coverage (FVC) and the LST within one growing season (from May to August 2017), at different spatial scales. The results showed that the FVC increased from 0.12 in May to 0.29 in August, and the LST increased first and then declined. The highest LST was 41.68 °C in July, while the lowest was 28.62 °C in August. At the grid scale, the LST increased first and then declined with the increase of the FVC on 25 May, 10 June, and 29 August; the FVC ranged from 0.29–0.38, 0.27–0.32, and 0.29–0.38 with the preference of the ‘turning point’, respectively. A negative correlation was identified between the FVC and the LST and without any ‘turning point’ in the fitting curve on 28 July. The correlation between FVC and LST complied with the grid scale at the sample area scale. The coupling analysis of landscape pattern expressed by FVC and LST showed that, the landscape evenness, Euclidean nearest neighbor distance, and landscape splitting degree all showed strong coupling correlation in any study period (P). The landscape aggregation of FVC and LST showed a good coupling at the relatively high and low air temperature conditions of P1 and P3. Landscape contagion showed a good coupling between FVC and LST at relatively moderate air temperature condition of P1 and P4. Air temperature conditions and characteristics of vegetation coverage should be considered for a more targeted analysis when analyzing the relationship between FVC and LST and attention should be paid to the timing and type of study area in practical application.

Using Traditional Medicinal Plants from Arid and Desert Rangelands as a Potential Treatment for Covid-19 in Southern Tunisia

Rangelands provide good services, including forage for livestock, aromatic and medicinal plants, wildlife habitat, fuel wood, and the watershed. In the arid and desert rangelands of Tunisia, several medicinal plants are used locally in traditional medicine. Many of them have been scientifically investigated and validated. This study aimed to document the different plants used recently to treat and prevent Covid-19 by the rural communities in southern Tunisia. One hundred persons that were ensured to be cured after their infection by Covid-19 were asked to indicate what plants were used to prevent or treat the pandemic disease. It is noteworthy that the selected respondents did not use any other medication than medicinal plants due to the high price of medicament. Additionally, they had not received any Covid-19 vaccinations to date. Five species were harvested from the range lands to be used by the rural population in south Tunisia to treat and prevent Covid- 19. The plants included Rosmarinus officinalis, Thymbra capitata, Peganum harmala, Artemisia herbaalba and Astragalus armatus. These species are medicinally essential when it comes to treating several human diseases. Still, there are no new scientific findings on whether these conclusions are valid. These results can still be the subject of future scientific research.

Modification of O-ring intrauterine devices (IUDs) in mares: Contraception without estrus suppression

A significant welfare concern for those within the horse industry is that of the overpopulation in free-roaming horses in the western US. The goal of the present study was to identify a humane and inexpensive means of providing contraception and reducing pregnancy rates in a way that could be applied to free-roaming horses on the western U.S. open range lands. A series of studies was conducted utilizing the previously-described silastic O-ring intrauterine devices (IUDs). Throughout these studies pregnancy was successfully prevented in mares with an O-ring IUD, but collective retention rates failed to exceed 50% regardless of size or durometer (material hardness/malleability). When the O-ring IUDs were compared to the recently-described Y-design IUDs (Holyoak et al., 2021) the Y-design IUDs had a markedly greater rate of retention; therefore, the Y-design IUDs would be most appropriate for potential use in free-roaming horses. Assessment of mare records revealed that the vast majority of mares continued to have ovulations and mating continued to occur while the IUDs were in place. A few mares had multiple small ovarian follicles when the IUD was in utero. Findings indicate that utilizing an IUD with the expectation of estrus suppression in mares would fail to be fruitful.

Hydrological Responses of Watershed to Historical and Future Land Use Land Cover Change Dynamics of Nashe Watershed, Ethiopia

Land use land cover (LULC) change is the crucial driving force that affects the hydrological processes of a watershed. The changes of LULC have an important influence and are the main factor for monitoring the water balances. The assessment of LULC change is indispensable for sustainable development of land and water resources. Understanding the watershed responses to environmental changes and impacts of LULC classes on hydrological components is vigorous for planning water resources, land resource utilization, and hydrological balance sustaining. In this study, LULC effects on hydrological parameters of the Nashe watershed, Blue Nile River Basin are investigated. For this, historical and future LULC change scenarios in the Nashe watershed are implemented into a calibrated Soil and Water Assessment Tool (SWAT) model. Five LULC scenarios have been developed that represent baseline, current, and future periods corresponding to the map of 1990, 2005, 2019, 2035, and 2050. The predicted increase of agricultural and urban land by decreasing mainly forest land will lead till 2035 to an increase of 2.33% in surface runoff and a decline in ground water flow, lateral flow, and evapotranspiration. Between 2035 and 2050, a gradual increase of grass land and range land could mitigate the undesired tendency. The applied combination of LULC prognosis with process-based hydrologic modeling provide valuable data about the current and future understanding of variation in hydrological parameters and assist concerned bodies to improve land and water management in formulating approaches to minimize the conceivable increment of surface runoff.

Meadow forage production and resource-saving methods for increas-ing the productivity of forage lands in Yakutia (review)

The major sources of rough feed production in Yakutia are native hayfields and range lands, which provide 85 % of all feed. Natural grasslands and range lands occupy extensive grounds – 1.4 million hectares, of which 740 thousand hectares are hayfields and 670 thousand hectares are range lands. Grasslands of Yakutia are economically the most important source of sup-porting the agricultural sector and the livelihoods of the local population. The article analyzes the developed agritechnologies for improving grass and range lands of Yakutia and substantiates promising energy-saving methods for yield enhancement during land reforms. Currently, the research on the improvement and restoration of grass and range lands is focused on energy-saving, the use of renewable local resources and the biologization of grassland culture in order to increase the productivity and bulk feed quality. The analysis of the northern grassland culture development during the intensification has shown that the development of own seed multiplication system of released varieties and species of legume grasses makes it possible to introduce successfully energy-saving agritechnologies. The article proposes various methods of energy-saving in agritechnologies, such as: application of organic fertilizers, use of the released local varieties and species of perennial grasses, increase in the area of legume-grass plant formations for improving the feed quality and the use of multiple-function agricultural equipment for cost saving.

Modeling and Prediction of Land Use Land Cover Change Dynamics Based on Land Change Modeler (LCM) in Nashe Watershed, Upper Blue Nile Basin, Ethiopia

Change of land use land cover (LULC) has been known globally as an essential driver of environmental change. Assessment of LULC change is the most precise method to comprehend the past land use, types of changes to be estimated, the forces and developments behind the changes. The aim of the study was to assess the temporal and spatial LULC dynamics of the past and to predict the future using Landsat images and LCM (Land Change Modeler) by considering the drivers of LULC dynamics. The research was conducted in Nashe watershed (Ethiopia) which is the main tributary of the Upper Blue Nile basin. The total watershed area is 94,578 ha. The Landsat imagery from 2019, 2005, and 1990 was used for evaluating and predicting the spatiotemporal distributions of LULC changes. The future LULC image prediction has been generated depending on the historical trends of LULC changes for the years 2035 and 2050. LCM integrated in TerrSet Geospatial Monitoring and Modeling System assimilated with MLP and CA-Markov chain have been used for monitoring, assessment of change, and future projections. Markov chain was used to generate transition probability matrices between LULC classes and cellular automata were used to predict the LULC map. Validation of the predicted LULC map of 2019 was conducted successfully with the actual LULC map. The validation accuracy was determined using the Kappa statistics and agreement/disagreement marks. The results of the historical LULC depicted that forest land, grass land, and range land are the most affected types of land use. The agricultural land in 1990 was 41,587.21 ha which increased to 57,868.95 ha in 2019 with an average growth rate of 39.15%. The forest land, range land, and grass land declined annually with rates of 48.38%, 19.58%, and 26.23%, respectively. The predicted LULC map shows that the forest cover will further degrade from 16.94% in 2019 to 8.07% in 2050, while agricultural land would be expanded to 69,021.20 ha and 69,264.44 ha in 2035 and 2050 from 57,868.95 ha in 2019. The findings of this investigation indicate an expected rapid change in LULC for the coming years. Converting the forest area, range land, and grass land into other land uses, especially to agricultural land, is the main LULC change in the future. Measures should be implemented to achieve rational use of agricultural land and the forest conversion needs to be well managed.

Thar Desert and its Natural Resources: A Case Study of the District Tharparkar in Sindh Province of Pakistan

The research study aims to display natural resources of Thar Desert area ofdistrict Tharparkar in Sindh. It is being studied over the years that DistrictTharparkar is totaled as a richest district in natural resources, such as coal,granite, salt mines, china clay, livestock, range land forest and mushrooms.The topography of the District 99% area covered in the desert which is knownas the part of Thar Desert. The Thar Desert existed into two countriesPakistan and India. The discovery of Thar Coal Reserves is one of thesignificant developments in the history of Sindh province of Pakistan whichplaced country at 7th among world top 12 richest coal reserves countries dueto its economic worth. On the basis of the previous studies; it is expected thatThar coal reserves having the potential to solve the energy crisis of Pakistan.The availability of granite is 26.05 billion tons found into 8 to 10 differentcolors in the area of Nagarparkar. Moreover, China clay extracted at 12 to 14different locations and around 2000 people employed in the different fields.Thar Desert of Pakistan has around 120 salt lakes and around 400 laborerswere employed to harvest salt. The Rangeland forests in the desert area of thedistrict represents the main source of livelihood is livestock and the areas arehighlighted the most densely populated in livestock in Sindh province ofPakistan.

Problems of Efficient Use of Natural Pastures

The North-Eastern part of Russia is a large territory with a harsh climate. Here temperature range from -65 C to +35 C. Soil is cryosolic and pale-yellow. Native people living on that territory cultivate crops, breed horses, reindeers, and livestock animals. More than 90% of agriculturally used areas is a forage land. The article describes topical issues of range lands use – useless lands, areas with difficult access, the anthropogenic effect on range lands fertility. The evaluation method is recommended for research. Practical value is caused by the approbation of the evaluation method using modern geoinformation technologies. Also, the article shows the mathematical and economical model of forage lands use based on the method. The article concludes that modern information technologies contribute to an increase in forage lands use effectiveness.

Birth Characteristics and Pre-Weaning Lamb Growth of Grazing Sudan Desert Ewes Supplemented in Different Reproductive Stages

This work was conducted to study effect of supplementary feeding at different reproductive stages on birth characteristics and pre weaning growth performance of lamb born to desert sheep (Hamari subtype) raised on natural range in West Kordofan State, Sudan. Ninety ewes of similar age and live weight were used in the study. Ewes were divided into three feeding group of 30 animals each. Group A was given concentrate supplement for one month before mating, one month during mating, and one month before lambing; group B was given the supplement for one month during mating and one month before lambing, while group C was left as a control group kept on natural grazing. The concentrate diet consisted of sorghum grains 15 %, groundnut cake 20 %, molasses 15 %, wheat bran 25 %, groundnut hulls 23 %, salt 1 % and 1 % limestone, and was offered at a rate of 500 gm./ewe/day. All animals were allowed to graze on natural range and were watered every 2-3 days. The result indicated that birth weight in general and that of ram lambs was heavier in concentrate supplemented ewes. Although there was no significant difference between supplemented and grazing ewes on pre-weaning growth rate of their lambs yet lambs born to non-supplemented ewes had lower total live weight gain. It is recommended that feed supplementation and range improvement programs are needed as water harvesting and reseeding of range lands to reduce stress of long journies searching for water and forage, to improve productive performance of sheep and pre-weaning growth of their lambs.

Mobility loss and its restoration in China grasslands.

Loss of mobility in rangeland use has emerged as a dominant theory to explain ecosystem degradation in the research area of rangeland ecology. The loss of mobility in rangeland use in China resulted from multiple interacting natural and social factors as well as policy changes. Re-establi-shing mobility in rangeland use is critical to rangeland restoration and sustainable management in China. However, the recovery of rangeland might be difficult through simply reverting to traditional rotational grazing. Alternatively, we explored various state-of-the-art rangeland management techniques, including smart fence, intelligent wearables for livestock, and rapid forage biomass measurement using drones. Such novel rangeland management techniques could be used in different regions with different climate and vegetation in China to re-establish mobility in rangeland utilization. Paired with these advanced techniques, new rotational high-mobility grazing systems could further integrate with other essential measures of grass-livestock husbandry in China, such as balancing of forage production and livestock grazing, supplemental forage of livestock, and replenishment of soil nutrients in rangeland. All these practices would ensure a more sustainable and effective utilization of rangeland in China.

Chemical composition and in vitro digestibility of some range plants

This study was carried out to determine chemical composition and in vitro dry matter and organic matter digestibility of range plant species of the area. Samples were collected from range lands at full maturity stage, dried under shade and subjected to chemical analysis and dry matter and organic matter in vitro digestibility for Vigna sunhum, Andropogan gayanus, Pennisetum Pedicelatum, Shoenfeldia gracilis and Stylothanis flavicans were determined. The data was analyzed via analysis of variance and differences among means were determined using Least Significant Difference (LSD) test. The results showed that the legumes (Vigna sunhum and Stylothanis flavicans) were significantly higher (P≤0.01) in their crude protein content and the percentage of crude protein respectively was 13.4% and 10.00% while the grasses were significant (P≤0.05) higher in Crude Fibre (CF), ash, Acid Detergent Fibers (ADF) and Neutral Detergent Fibers (NDF). Crude fiber % values were 41.78, 43.37 and 46.07% for Pennisetum Pedicelatum, Andropogan gayanus and Shoenofeldia gracilis, respectively. The acid detergent values were 53.85, 47.74 and 53.39 for the three weeds. (P≤0.05), while the ratio of neutral detergent was significantly higher (P≤.05) in grasses than in the two legume species; 87.22, 82.35 and 88.99% for the three grasses respectively. Similarly higher in vitro dry matter and organic digestibility coefficients were obtained from legume species than grasses. The study concluded that, the studied grasses were higher in fiber content and lower in their protein content but, legumes grasses (Vigna sunhum, Pennisetum Pedicelatum and Stylothanis flavicans) had high nutritive value and in vitro digestibility which may provide ruminants with the needed protein and energy.

“Silent” circulation of Trypanosoma spp. in Tabanids (Diptera: Tabanidae) and Cattle in a Tsetse free Range land of Ngaoundere (Adamawa-Cameroon)

The Adamawa region falls within the tsetse belt of Cameroon but harbours isolated pockets of tsetse free range lands like Ngaoundere. There is no report on the occurrence of tsetse and bovine trypanosomosis in Ngaoundere. To provide information on this subject, two Vavoua traps were used to trap vectors of bovine trypanosomiasis and at the same time, blood was collected from cattle. Genomic DNA was extracted from buffy coat of cattle blood (n=42) and biting flies (n=53). The nested PCR was used to screen the samples for Trypanosoma spp. During the 14 days of trapping in November and December 2017 in Ngaoundere, 127 flies were documented and classified under two taxa: Tabanidae and Stomoxyini. Three Trypanosoma spp. DNA was isolated from tabanid (18.9%) samples and identified as T. theileri, T. vivax and T. evansi and two of them that is T. theileri (4%) and T. vivax (3%) were also detected in cattle (7%). There was no case of trypanosome DNA isolated from all the screened Stomoxyini. This result indicates the “silent” transmission of T. theileri and T. vivax by tabanids in the absence of glossines in Ngaoundere.Keywords: Trypanosomes, tabanids, stomoxyini, PCR, Ngaoundere, Adamawa-Cameroon.

English

The study was undertaken to explore the nutritive potential of cassava leaves and Azolla as supplementary source of crude protein to cattle fed on either mixed range grass hay or Bracharia Mulato II. Two experiments were carried out, the first was the determination of the biomass yield of Azolla, its relative growth rate and doubling time while the second was a feeding trial to determine the performance of small East African Shorthorned Zebu heifers of similar age and weight. The heifers (four each) were randomly assigned to six treatments in the feeding trial that ran for 16 weeks. The doubling time for Azolla was 5 days while the relative growth rate was 0.15 g/g/day. The chemical analysis indicated that Azolla is rich in crude protein (18.8%) and minerals (3.29% calcium, 2.66% potassium and 0.15% phosphorus and other minerals in trace levels). All the supplemented groups showed more weekly weight gains ranging from 0.75 to 1.11 kg per day more than the control. Overall, the treatment with Azolla or cassava showed slightly higher but insignificant increases in weight gains. Azolla and cassava leaves can therefore be considered as potential feed for livestock. Key words: Arid and range lands, cattle, doubling time, relative growth rate.