Study on Breeding Practices and Reproductive Performance of Black-Head Somali Sheep under Traditional Management System: The Case of Awbarre District, Eastern Ethiopia

The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head Somali sheep under a traditional management system. Purposive and simple random sampling techniques were used to select targeted kebeles and households, respectively. A total of 120 households were selected from four kebeles, each of 30 households, based on the production system and sheep population. Semi-structured questionnaires, group discussions, key informants interviews and field observations were used to generate the required data. The primary purpose of keeping sheep was for income generation, followed by saving as a future asset. The majority (89.2%) of the respondents separated male and female animals during herding. The selection criteria for breeding rams were appearance, growth, pedigree, and color while for breeding ewes were appearance, adaptability, pedigree, color, and lamb growth. The overall weaning age of Black-head Somali sheep in the study area was 3.7 months for both males & females. The castration of male sheep was common for the purpose of fattening, fattening with breeding control and breeding control as well. The castration is mainly performed during the summer and autumn and the methods of castration were both traditional and modern methods, the traditional castration method being the most important one in pastoral areas. The age of sexual maturity was 7.64 months for rams and 8.97 months for ewe’s male and female lambs in the pastoral area and 8.42 & 8.38 for rams & ewes in agro-pastoral and overall lambing interval was 11 months. On average, the ewe of Black-head Somali sheep in pastoral & agro-pastoral could produce 9.49 & 9.57 lambs, respectively in their lifetime. As the pastoralists and agro-pastoralists indicated the source of the breeding ram was their own, so the exchange of breeding ram is recommended to minimize the risk of inbreeding and further studies of on-farm performance investigation would be necessary to be carried out so as to understand the uniqueness of the breed better.

Management Practices and Production Constraints of Indigenous Somali Cattle Breed in Shabelle Zone, Somali Regional State, Ethiopia

This study was conducted in Shabelle zone of Somali Regional State to assess management practices and production constraints of indigenous Somali Cattle. A total of 200 household heads were selected from four cattle potential districts;Dhanan, Ber’ano, Godey & Adadle. The relevant information was collected through semi-structured questionnaire, focus group discussion, key informants interview, and personal observations. Majority of the respondents were illiterate. The average cattle holding size was 8.97 heads/household and cattle were mainly kept for milk production. The major feed resources in the study area were natural pasture and crop residue, and communal grazing was the most important feeding system in the area. Feed shortage was a problem hindering cattle production in the study area during dry season mainly January up to March. Animals traveled long distances to watering points (>5 km) during dry season, while in wet season, animals were watered in nearby water sources. Cattle housing was open kraal fenced with the thorned plenty acacia trees and calves were housed separately from other cattle. Breeding in the study area was uncontrolled and was bred with their own or neighbors’ bull. Age at first mating, age at first calving and calving interval were 3.25 years, 4.05 years and 16.56 months, respectively. The daily milk yield and lactation length were 2.22 liters and 8.07 months, respectively. The production and reproduction performance of Somali cattle was relatively higher than other local breeds in the country mainly in terms of milk yield and fertility potential under the existing environmental conditions. The major constraints of cattle production were feed shortage, disease, water scarcity, lack of veterinary services, marketing problem and predator. Among those constraints, inadequate supply of quality feed, diseases and water shortage were the main reasons for low productivity of cattle and are the major factors limiting productivity. Therefore, to sustain the production system in the study areas, it is recommended to improve the current condition of communal rangelands through management of degraded areas by awareness creation on the value of these common resources and development of rules and regulation to sustain the existing resource and implement over the utilization of communal/pastoral rangeland management systems to reduce constraints such as shortage of feed, drought and grazing land deterioration which perpetuated through time due to land-use changes and seasonal fluctuation).

Hygienic Production and Post-Harvest Handling Practices of Raw Camel Milk in Degahbour District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to assess hygienic production and postharvest handling practices of raw camel milk in Degahbour district. The survey studies were based on a total of 120 (2 production systems * 2 rural kebele * 30 households) milk producers, which were selected from Degahbur district using stratified sampling technique. Data from the selected producers were collected using questionnaire survey and field observation. The results showed that the majority of the sampled household heads in pastoral (93.3%) and agro-pastoral (76.6%) production systems were illiterate. Moreover, none of the respondents in the study area had training on hygienic milk production and postharvest handling practices. The study result also indicated that none of the respondents in the study area washed the udder of milking camel before milking. Moreover, only 6.6% of pastoralists and 25% of agro-pastoralists wash their hands before milking. Equipment made of wooden materials are mainly used for milking, whereas, plastic jerry-cans were most commonly used for storage. About 45% of the pastoralists and 81.6% of the agro-pastoralists were cleaning milk vessels regularly;however, majority of the respondents both production systems were using water from non-tap sources for hygienic practices. Bosciaminimifolia, Acacia ethaica and Blanitesgalabra were the most commonly used plant species for smoking in the study area. Therefore, hygienic production and postharvest handling practices should be followed to improve the quality and suitability of camel milk for its intended use in the study area.

Sheep Production Systems and Breeding Practices for Selected Zones of Tigray, Northern Ethiopia

A study was undertaken to identify the production system, breeding practices and major production constraints of common Tigray highland sheep in 16 rural kebelles from eight districts of Tigray Regional State. A total of 480 households (30 households for each rural kebelle) were selected purposively to collect data through personal observations and a detailed structured questionnaire. Mixed crop-livestock production system was the dominant farming system in all the study districts. The farmers kept a variety of livestock species including sheep, goats, cattle, chickens horse, donkeys and bee colony. Sheep, principally as source of income, meat for home consumption, production of manure and for socio cultural purposes, are commonly herded with other species in the open grazing fields by young boys in a family. Mating was generally uncontrolled. Body size, growth rate and adaptability were the major traits in selecting rams, whereas ewes were selected based on body size, twining ability and lambing interval. Majority of sheep across all districts are housed in structures known as Gebella which is built from stone and mud wall and tree/corrugated iron sheet roofing separated from the main family house. The major constraints hampering sheep production in the study areas were feed shortage (0.25), lack of capital (0.24), insufficient veterinary services (0.2), limited grazing land (0.2), water scarcity (0.06) and predators (0.05) with index value indicated in parenthesis. In order to improve the productivity of sheep, it is important to involve farmers and other stockholders in addressing these constraints and designing breed improvement interventions, considering the overall farming and breeding practice of smallholders.

Effects of Inclusion of Different Levels of Ethiopian Thyme (Thymus schimperi Ronniger) as Natural Additive on Chemical Composition and In Sacco Dry Matter Degradability of Total Mixed Ration and Feed Ingredients

This study evaluated the effects of the inclusion of Ethiopian thyme (Thymus schimperi Ronninger) to natural pasture hay (NPH), noug seed cake (NSC), wheat bran (WB) and total mixed ration (TMR) on the chemical composition and in Sacco dry matter (DM) degradability of the feeds. The Thyme plant used for the study was collected from Dinsho and Tarmaber districts in the highlands of Ethiopia. Samples of the TMR and NPH, WB and NSC with or without thyme were divided into two parts and ground to pass through 1 mm screen for chemical analysis and 2 mm screen for in sacco DM degradability. The TMR contained 50% NPH, 32.5% WB, 14% NSC, 3% molasses and 0.5% common salt. The feed ingredients (NPH, WB and NSC) and the TMR were incubated without thyme or with thyme substituting the diet at 8%, 16% and 24% levels of treatments. The chemical composition of all the feeds differed significantly (P In sacco rumen dry matter degradability of NPH, WB, NSC and TMR was increased (P in sacco DM degradability of NPH at all incubation hours was higher (P Thymus schimperi plant up to a level of 24% DM in feed can reasonably stimulate the growth and activity of the certain rumen microbes that promoted an improvement in ruminal DM degradability of the diet with the thyme inclusion.

Identification and Chemical Composition of Major Camel Feed Resources in Degahbur District of Jarar Zone, Somali Regional State, Ethiopia

This study was conducted to identify major available camel feed resources and determine their chemical composition in Degahbur district. A total of 120 respondents were selected using purposive sampling technique. Data from the selected actors were collected using a semi-structured questionnaire survey, focus group discussion and field observations. The study revealed that the majority (82.5%) of the respondents in the study area were male headed households. Browsing trees and shrubs were the major available livestock feed resources both in dry (51.6%) and wet (68%) season, and followed by herbaceous species (26.6 and 23.7% for dry and wet season, respectively). The study identified about 20 herbaceous, 24 trees, 11 shrubs, 7 bush and 17 grass species which are used as camel feed in the study area. Chemical composition analyses of the sampled feeds indicated that there was a significant difference in crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) between species in different seasons. The NDF contents in the current study were above the critical value of 60% which was reported to result in decreased voluntary feed intake, feed conversion efficiency and longer rumination time. In general, the findings indicated that the use of improved forages and agro-industrial by-products as camel was minimal;thus, camels were fed on available feed resources which are poor in nutritional quality without any supplementation. Therefore, the study suggests the need for improving camel feeding practices in the study area to enhance camel productivity.

Digestibility of Sheep Ration Containing Different Levels of Native Grass Hay and Concentrate Mixture of Wheat Bran and Dried Food Left over

The experiment was carried out at Mekelle University livestock farm, Tigray, Ethiopia. 12 male yearling Highland sheep with an average live weight of 20 + 2.5 kg (mean ± standard deviation) were used in the experiment. The objective of the study was to investigate the effect of digestibility of sheep ration containing different levels of roughage and concentrate mixture on performance of highland sheep. Food left over was collected from Mekelle University student cafeteria and dried with sun light for 3 - 4 days. The experimental design was a randomized complete Block design (RCBD) with four treatments and three replications. The experimental animals were grouped into three blocks based on their initial live body weight, which was determined by weighing after overnight fasting. The experiment was carried out for 15 days including 5 days of adaptation period and 3 days of adaptation and harnessing (fecal bags). At the end of the feeding trial, digestibility trial was carried out for seven consecutive days. There was significantly higher (P 0.05) total DM intake in the supplemented group than in the control treatment. Digestibility of DM and OM were non-significance (P > 0.05) for all treatments. Generally, the present study indicated that supplementation of Tigray highland rams with concentrate mixture had an effect on performance of sheep and the effects were relatively more pronounced on rams supplemented with the highest level of concentrate mixture.

Heifer Body Weight Gain and Reproductive Achievement in Response to Protein and Energy Supplementation While Grazing Dormant Range Forage

Heifers grazing winter range require supplemental nutrients to complement dormant forage to achieve optimal growth and performance. A study was conducted to evaluate nutritional environment and effect of different supplementation strategies for developing heifers grazing dormant winter range. Eighty-four Angus crossbred heifers were stratified by body weight at weaning, allocated to one of six replicated pastures, and randomly assigned one of three supplemental treatments: 1) 908 g/d of a control supplement providing 340 g·hd-1·d-1 of CP with 130 g of rumen undegradable protein (RUP) and 614 MJ of ME (LRUP);2) 908 g/d of a RUP supplement providing 340 g·hd-1·d-1 of CP with 170 g of RUP and 567 MJ of ME (HRUP);or 3) 1814 g/d of a protein and energy supplement providing 340 g·hd-1·d-1 of CP with 120 g of RUP + 100 g of propionate salt (NutroCalTM, Kemin Industries, Inc.) and 1222 MJ of ME (LRUP + E). Body weights were taken in November, with monthly 12 h shrunk BW from January thru April, and again in September (at time of pregnancy diagnosis). Heifer average daily gain was similar throughout the developmental period except from d125 to d159 where LRUP + E supplemented heifers had greater gains

Management Practices, Utilization and Challenges of Donkey in Godey Town, Somali Regional State, Ethiopia

The study was conducted in Godey town of Shebelle zone, Somali Regional State, Ethiopia. The objective of the study was to assess management practices, utilization, and challenges of donkey. A total of 200 households who own working donkeys were selected purposely for this study. Data were collected using semi-structured questionnaires, key informants interviews, focus group discussions with communities who own donkeys and personal observations. The study revealed that the majority of the respondents were illiterate which might be associated with poor education access in the area. The study further revealed that 92% of working donkeys were involved in drought work, whereas 18% were used for pack work. The common feed resources for donkeys were feeds obtained from natural pasture, green maize leaves, hay, household wastes and grain supplements. Pipe water, river water, and pond water were the main water sources for working donkeys in the study area. About 91% of households kept their donkeys in an open backyard, while 9% of them kept them in a separate shed built adjacent to or a short distance away from the family home. Donkeys provide cart services in the study area, transporting various items weighing more than 300 kg in order to obtain a high benefit in a short period of time and are more than six days per week. Working donkeys in the current study area had a life span of fewer than 6 years, 7 - 10 years, and more than 10 years, with 18.5%, 75.5%, and 6%, respectively. The most important constraints that affect donkey production and utilization in the study area were a lack of feed, health problems (sickness, wounds, etc.), overloading and overworking, poor road and harnessing problems, and poor attitude/lack of awareness. As a result, in order to enhance working donkey management concerns, area-based development interventions that can overcome current constraints should be employed.

Handling and Hygienic Production Practices of Goat Milk in Degahbur District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to assess handling and hygienic production practices of goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 120 households were purposively selected for this study using a stratified sampling technique. The data were collected through the questionnaire, field observations, key informants interview and focus group discussions. The study showed that majority of the sampled households were illiterate. The goats were kept in an open kraal made of thorny acacia trees on an earthen floor that had no roof. The goats were milked inside these open kraals, and were sometimes contaminated with muck and animal dung mainly the rainy season which could raise the possibility of milk contamination & spoilage. Moreover, traditional hand milking was the only milking method and majority of the respondents didn’t wash their hands and the udder of the animal before milking, indicating low community awareness and knowledge of sanitary milk production procedures. Plastic equipment which is difficult to clean and can increase milk contamination and spoilage was used. About 43.3% of the pastoralists and 76.67% of the agro-pastoralists were cleaning milk vessels regularly. The most often used plant species for smoking milk handling equipment in the study area to extend shelf life and add flavor & aroma were Acacia ethaica, Blanites galabra, and Solanum Carense. The main constraints to hygienic goat milk in the area were identified to be poor barn hygiene, poor production procedures, disease, source of washing water and lack of extension services. In general, it can be concluded that handling and hygienic production practices of goat milk used in the study area were unsanitary, which may have been primarily caused by the community’s lack of awareness & understanding as well as a lack of supporting infrastructures. Therefore, the concerned bodies should place a high priority on the improvement of hygienic practices by carrying out various relevant development interventions, such as raising milk producers’ awareness, improving the health of goats, and providing the necessities for milk handling.

Study on Management Practices and Constraints of Black Head Somali Sheep Reared in Awbarre District of Fafen Zone, Somali Region, Ethiopia

The study was conducted to assess management practices and constraints of Black head Somali sheep in Awbarre district of Fafen zone, Somali regional state, Ethiopia. A total of 120 households were purposively selected for this study using purposive sampling technique. The data were collected through the questionnaire, key informants interview, focus group discussions & field observations. The primary purpose of keeping sheep was for income generation followed by saving, meat production, milk, social and cultural functions. The main feeds for sheep during wet season were communal & private natural pastures. In dry season, communal natural pasture, crop residues & private natural pasture were used. The major source of water during wet season was dam/pond, whereas in the dry season spring & pipe water were used. The majority of the respondents (85.8%) used houses enclosed with thorn woody trees and houses enclosed with stone/brick fence were also reported. Majority of the respondents used controlled mating system and sheep are bred to lamb when forage is plentiful because they are less drought tolerant than goats and to avoid unwanted lambing in dry season. Majority (90%) of respondents own their breeding ram and those who have no breeding males used their neighbors’ rams and borrow from others. The breeding rams were born in the flock implying that animals within the flock are very closely related which leads to inbreeding. The most important health problems affecting sheep were circling disease, sheep pox, tick lameness (tick paralysis), Peste des Petits Ruminants (PPR), bloating, and Foot & mouth disease (FMD). The major constraints hindering sheep production in the study area were shortage of veterinary service, feed shortage, scarcity of water, predators, diseases, and marketing. Therefore, to improve and increase the productivity of sheep production in the study area, better management practices and establishing of veterinary service centers are necessary.

Spatiotemporal Cattle Data—A Plea for Protocol Standardization

It was not until the end of the 1990’s that animal born satellite receivers catapulted range cattle ecology into the 21st century world of microchip technology with all of its opportunities and challenges. With the global navigation satellite system (GNSS), insight about how cattle use a landscape is being revealed from previously unknown temporal and spatial behaviors. The most common system to date for studying ungulate movement is the global positioning system (GPS). With its use has come a clarity and completeness in documenting spatial and temporal data in new and exciting ways that offer almost unlimited possibilities to better understand and manage economic and societal returns from animal dominated landscapes. However, its use on free-ranging cattle is not without challenges, some of which are yet to be optimally solved. To maximize the usefulness of GNSS data, consideration must be given to: 1) developing a standardized protocol for reporting and analyzing research that facilitates interpretation of results across different ecosystems;2) develop optimum ranges over which to collect satellite fixes depending upon the particular behaviors of interest;and 3) concurrently develop electronic hardware and equipment platforms that are easily deployed on animals and that are light, robust, and can be worn by cattle for extended periods of time without human intervention (e.g., changing batteries). Once data are collected, appropriate geographic information system (GIS) based models should be used to produce a series of products that can be used to implement flexible management strategies, some of which may support methodologies that are yet to be commercialized and adopted into future plant-animal interface management routines.

Evaluation of steroidogenic capacity after follicle stimulating hormone stimulation in bovine granulosa cells of Revalor 200~ implanted heifers

Background： Heifers not used as breeding stock are often implanted with steroids to increase growth efficiency thereby altering hormone profiles and potentially changing the environment in which ovarian follicles develop. Because bovine granulosa cell culture is a commonly used technique and often bovine ovaries are collected from abattoirs with no record of implant status, the objective of this study was to determine if the presence of an implant during bovine granulosa cell development impacts follicle stimulating hormone-regulated steroidogenic enzyme expression. Paired ovaries were collected from 16 feedlot heifers subjected to 1 of 3 treatments： non-implanted （n = 5）, Revalor 200 for 28 d （n = 5）, or Revalor 200 for 84 d （n = 6）. Small follicle （1 to 5 mm） granulosa cells were isolated from each pair and incubated with phosphate buffered saline （n = 16） or 100 ng/mL follicle stimulating hormone （n = 16） for 24 h. Results： Granulosa cells of implanted heifers treated with follicle stimulating hormone produced medium concentrations of progesterone similar （P = 0.22） to non-implanted heifers, while medium estradiol concentrations were increased （P 〈 0.10） at 28 and 84 d compared to non-implanted heifers indicating efficacy of treatment. Additionally, real-time PCR analysis in response to follicle stimulating hormone treatment demonstrated a decrease in steroidogenic acute regulatory protein （P = 0.05） mRNA expression in heifers implanted for 84 d and an increase in P450 side chain cleavage mRNA in granulosa cells of heifers implanted for 28 （P 〈 0.10） or 84 d （P 〈 0.05） compared to non-implanted females. However, no difference in expression of 3-beta-hydroxysteroid dehydrogenase （P= 0.57） and aromatase （P = 0.23） were demonstrated in implanted or non-implanted heifers. Conclusions： These results indicate follicles which develop in the presence of high concentrations of androgenic and estrogenic steroids via an implant tend to demonstrate an altered capacity to respond to follicle stimulating hormone stimulation. Thus, efforts should be made to avoid the use of implanted heifers to study steroidogenesis in small follicle granulosa cell culture systems.

Microbiological Quality of Goat Milk in Degahbur District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to evaluate microbiological quality of raw goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 40 pooled raw goat milk samples (each with a volume of 450 mL) were collected from the udders and milk handling equipment of targeted goat milk producers in the study area. The milk samples were subjected to laboratory analysis to evaluate total bacterial count (TBC) and total coliform count (TCC) in order to determine the microbiological quality of the raw goat milk in the study area. The study showed that the mean total bacterial count (TBC) and total coliform count (TCC) for raw milk samples collected from the udder were 4.92 ± 0.23 and 2.68 ± 0.36 log10 cfu·mL-1, respectively. The mean counts for samples collected from milk equipment were 5.61 ± 0.32 and 3.93 ± 0.21 log10 cfu·mL-1 for TBC and TCC, respectively. The values for the samples collected from pastoral production system were 5.63 ± 0.13 and 4.02 ± 0.20 log10 cfu·mL-1 for TBC and TCC, respectively. The average means of TBC and TCC for samples collected from the agro-pastoral production system were 4.9 ± 0.41 and 2.59 ± 0.37 log10 cfu·mL-1, respectively. Significant difference (P 0.05) in mean TBC and TCC was observed between milk samples collected from pastoral and agro-pastoral production systems as well as milk samples collected from udders and milk handling equipment of the producers. It could be concluded that both TBC & TCC of goat milk samples collected from the udder as well as from the milk handling equipment of producers exceeded the acceptable limits. This indicated that production practices performed during milk production and postharvest handling in the study area were unhygienic. Therefore, hygienic and proper milk production procedures should be followed to improve the quality of goat milk for its intended use in the study area.

Microbiological Quality of Raw Camel Milk in Degahbour District of Jarar Zone, Somali Regional State, Ethiopia

A cross-sectional study was carried out to evaluate microbiological quality of raw camel milk in Degahbour district. A total of 40 pooled raw camel milk samples (each with a volume of 450 mL) were collected from the udders and milk handling equipment of producers in Degahbour district. The raw milk samples were subjected to laboratory analyses to evaluate standard plate counts (SPC), total coliform count (TCC) yeast and mold count (YMC) to determine the microbiological quality of the raw camel milk in the study area. The overall mean SPC, CC and YMC for raw camel milk samples collected from the udder was 5.35 ± 0.19, 2.59 ± 0.16 and 1.71 ± 0.12, respectively. The overall mean counts for samples collected from the equipment of producers were 6.72 ± 0.17, 4.71 ± 0.23 and 1.61 ± 0.21 for SPC, CC and YMC, respectively. Significant difference (P 0.05) in mean SPC, TCC and YMC was observed between milk samples collected from pastoral and agro-pastoral production systems as well as collected from udders and milk equipment. In general, it was concluded that raw camel milk samples collected from the udder as well as from the equipment of producers were contaminated with SPC, CC and YMC, with loads exceeding the respective acceptable limits. Therefore, hygienic production and postharvest handling practices need to be followed to improve the quality and suitability of camel milk for its intended use in the study area.

Effects of grazing intensity to water source on grassland condition, yield and nutritional content of selected grass species in Northwest Ethiopia

Background:Savanna grasslands are globally important ecosystems consisting of one of the most extensive grazing lands with unique biodiversity.The objectives of the study were to assess the effect of grazing intensity on grassland ecosystem condition,herbaceous plant biomass production,and nutritional content of selected grass species.Methods:The study was conducted at Chagni Ranch,Northwest Ethiopia.Four transects to water source point at regular intervals of 20m between sampling plots along transects were used for data collection.The distance between the four transects was 200m in radius.Data were collected on grass composition,basal cover,litter cover,number of seedlings,and age distribution of dominant grasses(i.e.,young,medium,or old in terms of stage of maturity),soil condition in terms of soil compaction,and soil erosion linked to the effects of trampling by grazing animals along transects(hereafter referred to as transect)to water source point.The total sample size for grass species was 160 plots.The grassland ecosystem condition,herbaceous biomass,and grass nutritional content were used as response variables linked to transect from water source point.The effects of transect on grassland ecosystem condition scores and grass nutritional content were analyzed using the analysis of variance(ANOVA).Results:Grassland condition factors like grass composition,basal cover,litter cover,age distribution of dominant grasses,and soil condition were significantly(P<0.05)higher for the furthest transect to water source point than nearest transect.Out of the 28 identified herbaceous species,grasses accounted for 64.3%of the herbaceous community.Within grass species,about 55.6%were highly desirable in terms of palatability and grazing value(as most palatable species are susceptible to heavy grazing intensity).The results showed a significantly(P<0.05)higher proportion of perennial grasses at the furthest transect to water source point than nearest transect.The dry matter yield at the furthest transect(TD4)and third transect(TD3)were significantly(P<0.05)higher than the nearest transect to water source point(i.e.,the first transect(TD1)and second transect(TD2)).Ash,neutral detergent fiber,acid detergent fiber,and acid detergent lignin contents of Cynodon dactylon,Sporobolus pyramidalis,and Digitaria ternata were significantly(P<0.05)higher at the furthest transect to water source point than nearest transect.Grazing intensity had no significant effect on the crude protein content of Cynodon dactylon and Sporobolus pyramidalis at different transects.Conclusions:The results showed that the furthest transect to water source point were in good condition.Grass biomass production and the nutritional contents of grasses were higher for the furthest transect to water source point.The results suggested that increased grazing intensity towards water source point greatly reduced the abundance of desirable perennial grasses and the sustainability of grassland for livestock production.

Integrating space and time: a case for phenological context in grazing studies and management

In water-limited landscapes, patterns in primary production are highly variable across space and time.Livestock grazing is a common agricultural practice worldwide and a concern is localized overuse of specific pasture resources that can exacerbate grass losses and soil erosion. On a research ranch in New Mexico with average annual rainfall of 217 mm, we demonstrate with a quantitative approach that annual seasons vary greatly and examine foraging patterns in Angus-Hereford(Bos taurus) cows. We define five seasonal stages based on MODIS NDVI: pre-greenup, greenup, peak green, drydown and dormant, and examine livestock movements in 2008. Daily distance traveled by cows was greater and foraging area expanded during periods with higher precipitation. A regression model including minimum NDVI, rainfall and their interaction explained 81% of the seasonal variation in distance traveled by cows(P < 0.01).Cows explored about 81 ha·d^(–1) while foraging, but tended to explore smaller areas as the pasture became greener(greenup and peak green stages). Cows foraged an average of 9.7 h daily and spent more time foraging with more concentrated search patterns as pastures became greener.Our findings suggest that phenological context can expand the capacity to compare and integrate findings, and facilitate meta-analyses of grazing studies conducted at different locations and times of year.