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The productivity and management systems of free range local chickens in rural areas of Babati District, Tanzania
2018
Marwa, L.J. | Mbaga, S.H. | Mutayoba, S.K. | Lukuyu, Ben A.
Performance evaluation of Abergelle goat under community based breeding program in selected districts, northern Ethiopia
2018
Birhanie, Minister | Alemayehu, Kefyalew | Mekuriaw, Getinet
Milk production performance of Begait goat under semi intensive and extensive management in Western Tigray, North Ethiopia
2018
Hagos, A. | Gizaw, Solomon | Urge, Mengistu
The study was conducted in Kafta humera district of Ethiopia, (i) to investigate the milk yield of Begait goat under different management and (ii) to evaluate the effects of different non-genetic factors on lactation performance. Data were collected from 428 lactating does under two managements (semi intensive and extensive) during October 2014 and March 2016. Statistical analyses were carried out using the GLM procedure of SAS version of 9.2 software. The least squares means (with standard error) for daily milk yield, lactation milk yield and lactation length were observed to be 0.75±0.01 kg, 85.6±1.04 kg and 111±1.21 days under semi intensive management, respectively whereas under extensive management these were found as 0.55±0.01 kg, 56±1.43 kg and 101±1.57 days, respectively. The results of this study indicated that management system, parity number and season of birth affected all variables highly significantly.
Afficher plus [+] Moins [-]Gender aspects in the dairy value chain in Tanzania: A review of literature
2018
Sikira, A.N. | Waithanji, Elizabeth M. | Galiè, Alessandra | Baltenweck, Isabelle
Economic values of Begait cattle breeding-objective traits under low and medium input production systems in northern Ethiopia
2018
Mezgebe, Gebretnsae | Gizaw, Solomon | Urge, Mengistu
The study was conducted to estimate the economic values (EV) of Begait cattle breeding-objective traits and their effects on the returns to investment in breeding programs using bio-economic model. Production systems were described according to their level of input and sale age, namely, low input herd management (LIHM) and medium input herd management (MIHM) based on fixed herd size for genetic improvement of multiple traits. Results showed that all considered traits have positive economic values across production systems except pre weaning daily body weight gain (PrDG). However, production systems had significant influence on the magnitude of EV of traits. The MIHM was superior by 100 to 9% to the LIHM system. Regardless of the two production systems, calving interval (CI) had the highest EV followed by dressing percentage (DP) and mature weight (MWT). Although, the overall change of beef trait EV influenced the marginal profit through price and production variable changes at constant MY, the more sensitive change was observed with the changes of MY EV. Traits of milk yield had 1 to 12% increment on profit with 1 to10% improvement in its EV by rising milk price, reduced weaning and reduced culling rates. However, beef traits only made 5.1×10-7 to 2.3×10 -6% raises on profits with 18 to 50% increment in its EV by beef price increment and reduced age at first calving. The higher increments of profit parallel to the EV of milk production trait and mostly simultaneous improvements on CI have a great indication to give priorities on milk yield traits than beef traits in any Begait cattle improvement program. Therefore, improving milk production traits and fecundity traits simultaneously with their market outlet is better to increase the profitability of farmers and sustains the valuable breed in their habitat.
Afficher plus [+] Moins [-]Mitochondrial DNA variation of indigenous goat populations from Peste-des-petits-ruminants outbreak in South Kivu, Democratic Republic of the Congo
2018
Bwihangane, B.A. | Gitao, G.C. | Bebora, L.C. | Tarekegn, M.G. | Nicholas, S. | Bacigale, Samy B. | Svitek, Nicholas
This study was conducted to investigate the genetic diversity at d-loop of mitochondrial DNA and establish the possible maternal lineages of indigenous goat breeds in Democratic Republic of Congo (DRCongo). Phylogenetic relationships among and within 111 goats from three indigenous populations from a peste-des-petits ruminants outbreak in South Kivu, Eastern of Democratic Republic of the Congo and 22 goats sequences from the gene bank were analysed using mitochondrial control region sequences (d-loop region). The results show that a total of 120 segregating sites, 56 haplotypes and 124 mutations were found in a 1220-bp sequence. The mean haplotype diversity and nucleotide diversity were 0.971±0.007 and 0.011±0.002, respectively with the overall number of nucleotide differences of 10.73. The phylogenetic analysis showed that all goat sequences were clustered into two haplogroups (A and B), of which haplogroup A was the commonest. The global analysis of molecular variance (AMOVA), incorporating all the three populations independent of any hierarchical clustering, indicated that 83.22% of the total genetic variation present in studied goats was explained by genetic differences between individuals (pv= 0.327), 11.18% among groups (pv=0.000*) and only 5.60% of the variation was attributed to genetic differences between populations (pv=0.003*). These results conclude that there are high levels of intrapopulation diversity in Mwenga-Shabunda, Fizi and Kalehe goats and the weak phylogeographic structuring, thus, suggested that there existed strong gene flow among goat populations probably caused by extensive trans-border movement of goats in the past
Afficher plus [+] Moins [-]The features of lime stands on permanent research plots in Leningrad region
2018
Dobrovolsky, A., Saint Petersburg State Forest Technical Univ. (Russian Federation) | Antonov, O., Saint Petersburg State Forest Technical Univ. (Russian Federation)
The objects of research are the lime-tree forests of the Leningrad region. The studies were carried out on 2 permanent plots established by the authors in May 2013 in the Lisino forest district (Leningrad region, Russia). The goal of research was to obtain a complex characteristic of stands dominated by linden (Tilia cordata). The objective of the research included a taxation and geobotanical description on permanent plots and studies of the soil cover (morphological and agrochemical characteristics of soils). The general health status of stands on the surveyed areas was determined as satisfactory – mean score 2.5 and 2.8 (relevant health status was determined with the help of the following 6-grade scale for each tree: 1 – no signs of weakening; 2 – weakened tree; 3 – very weakened tree; 4 – partial mortality of the tree; 5 – dead-standing trees of the current year; 6 – dead-standing trees of previous years). The average mortality rate varies from 3.05% year-1 on the sample plot 2 to 5.7% year-1 on the sample plot 1. Vegetation on sample plots attributes to a nemorose-herbal series of forest types, soils – to a podzolic type with a weak development of the podzol-forming process. They were well-mediated ones by humus in the upper horizon. This fact was facilitated by the lime litter: a lime has a deep root system to take up nutritional chemicals from a greater depth, where moraine loams enriched with calcium carbonate located. Old-aged forests of this type are being in the phase of gap dynamics now. This means that they can occur for a rather long time in the same place, however, the lime-tree forests of natural origin are constantly under threat of being replaced by spruce. The results of our study have shown that low levels of soil mineral nutrients supply are sufficient for the successful linden growth.
Afficher plus [+] Moins [-]Improved activity data for accounting greenhouse gas emissions due to management of wetlands
2018
Butlers, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Ivanovs, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The study represents results on remote sensing methods based evaluation of land use and land use changes in former and existing peat extraction areas in Latvia. The aim of the study is to elaborate activity data set for the National GHG inventory for the wetlands remaining wetlands for peat extraction. The study results provide sufficient data for application of the default emission factors for the peat extraction sites and flooded lands. Abandoned peat extraction fields, which are not yet afforested, flooded or rewetted, should be reported as peat extraction sites following a conservative approach in application of the emission factors. The study results can be used to report land use changes since 1990; however, linearized approach in calculation of the land use change may result in overestimation or underestimation of GHG emissions in certain periods of time. According to study results, the area of peat extraction sites is considerably bigger than currently reported in the National GHG inventory, mainly due to considerable areas of abandoned peat extraction fields. Flooded lands may be a significant source of emissions and should be introduced in the National GHG inventory to secure consistency of reporting. Methodology for calculation of GHG emissions from flooded lands should be also elaborated. It is also necessary to elaborate emission factors for fertile and no fertile peat extraction sites and continue work on separation of different soils in the inventory to increase accuracy of calculations.
Afficher plus [+] Moins [-]Use of the LiDAR combined forest inventory in the estimation of felling site stocks
2018
Seleznovs, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Dubrovskis, D., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Dagis, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Smits, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Baltmanis, R., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Precision of the forest inventory still is one of the most important problems in the forestry nowadays. The aim of this research was to estimate the results of the combined forest inventory (CFI), using high spatial resolution aerial images in the planned areas of clear-cuts, comparing the results with the calipering and production files of harvesters. Testing of algorithms showed considerable difference in results between the CFI, forest inventory data and harvester production data. CFI results and production data had a close correlation with R2 =0.83. Comparing CFI calculated growing stock with production data, the average relative error amounted to 10.7%, which means the possibility for integration of these results into the forest inventory system. Comparing to CFI, there is a weak correlation between forest inventory and production data with R2 =0.34. The results indicate that LiDAR CFI technology can be used in the forecasting of the forest management, offering precise information about potential amount and economic value of assortments.
Afficher plus [+] Moins [-]Factors affecting productivity of machined logging in thinning using small size forest machines
2018
Zimelis, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Kaleja, S., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Luguza, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of the research is to find out changes in productivity depending on the diameter of the tree to be cut as well as the most important factor influencing the reduction of productivity using small size forest machines in thinning in Latvia. The equipment used in the study – both the harvester and the forwarder is Vimek. The results of the research confirm the appropriateness of the exact technique in thinning if diameter of the harvested trees is 3 to 30 cm. The average productivity of the harvester achieved with a harvester head Keto Forest Eco (option 2) in Norway spruce stands with 8 cm weighted average tree reached 9.59 m**3 hE-1, in deciduous tree stands with 9 cm weighted average was 10.17 m**3 hE-1, but in Scots pine stands with 12 cm average weighted tree diameter reached 10.19 m**3 hE-1. By using the Keto Forest Eco Harvester head according to the thinning productivity figures, no significant difference among the tree species was detected. For the forest owner to predict the theoretical productivity of the harvester, it is possible to apply the equation R = K + KD * D, that is statistically significant, R2 =0.85. This equation is applicable to thinnings when the diameter of thinned trees is between 4 and 25 cm. Forwarder’s average productivity in thinned stands is 8.63 m**3 hE-1.
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