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Selection efficiency for growth performance of Menz sheep in a community-based breeding program
2020
Abebe, A. | Banarjee, S. | Goshmie, S. | Bisrat, A. | Besufikad, S. | Zewdie, T. | Gizaw, Solomon
The study was undertaken to evaluate the efficiency of selection on growth performance of Menz sheep under a community-based breeding program (CBBP) from the period of 2009 – 2017. A total of 3996 lamb records (ram lambs 2025/ ewe lambs 1971) were used to evaluate the phenotypic and genetic factors affecting the growth traits of Menz sheep. REML in Wombat and General linear model on SAS (version 9.0) were used to evaluate selection efficiency for growth of Menz sheep. The least squares means and standard errors on phenotypic growth weight for birth, weaning age, six month age and yearling age were 2.58±0.004, 8.99±0.02, 13.28±0.02 and 19.94±0.06 kg, respectively. The effect of sex was significant (p<0.001) only for birth weight and no significance effect (p>0.05) was observed for weaning, six month and yearling weights. All growth traits were not affected by fixed effect of parity and birth type in this particular study. However, birth season and birth year had a great influence (p<0.0001) on all growth traits. The genetic trend on estimated breeding values (EBV) was not consistent across years and varied between sexes. The highest EBV for weaning, six month and yearling were recorded for the year 2013 and the lowest in 2009 (at weaning and six month) and 2015 (at yearling).The female EBV (at weaning, six month and yearling) was higher than male for the current (2017) and base population (2009).The responses to selection as compared to base population (2009) for birth, weaning, six month and yearling weight were – 0.00446Kg, + 0.11Kg, + 0.54Kg and + 0.75Kg respectively. This study indicates that improvement in body weight for Menz sheep through CBBP is possible; however, the response to selection varied across years and its pattern was irregular for the implemented years due to the problem on selection of breeding rams (lower availability of breeding rams) and management effect.
Show more [+] Less [-]Survivability of lambs under village management condition: The case around Jimma, Ethiopia
2011
Belay, Berhanu | Haile, Aynalem
The influence of non-genetic factors on lamb survivability at various ages up to 360 days was studied under village management condition in Jimma, Ethiopia. The overall least squares means of lamb survival rate was 89.0 at 0-60, 81.5 at 0-120 and 50.0 % up to 360 days. The survival rate of lambs up to weaning (120 days) was 81.5 %. Season of birth consistently exerted a significant effect (p<0.05)) on lamb survival. Lambs born during the post rain and dry periods showed a higher survival rate than lambs born during the wet season. Districts showed a significant effect (p<0.05)) on survival rates of lambs. Lambs born in land scarce areas (Dedo) had a low survival rate than lambs born in Seka (land available area). Type of birth did not exert an influence (p>0.05) on lamb survival. Sex had a significant effect (p<0.05) on survivability of lambs at later stages and the females showed higher survivability rate than males. Mortality tended to decrease with an increase with birth weight and decreased as parity increased. The birth weight showed a significant effect (p<0.05) on survival rate of lambs. The lambs with birth weight of 2 kg and above were showing higher survival rate. The lambs with 1.5 kg and lower birth weight showed high mortality rate. The study revealed that, adequate measures to be taken to curb mortality of lambs. The selection of heavier weight and larger litter at birth coupled with improved management could be a means to improve lamb productivity in the villages.
Show more [+] Less [-]Characterization of fish production and marketing practices under small-holder fish farming systems of eastern Kenya
2013
Oyieng, Edwin P. | Charo, H.K. | Kahi, A.K. | Ojango, Julie M.K.
Aquaculture, a sub-component within the fisheries sector is a vital economic activity and livelihood component of rural communities living beside rivers and river floodplains in East Africa. It provides a good alternative source of income and proteins for rural communities. This study aimed to characterize fish production and marketing practices in smallholder farming systems under a national Economic Stimulus Programme (ESP) in the Eastern province of Kenya, and to determine the traits of economic importance to the farmers. Information was collated from 198 farmers, 13 traders and three key informants within Meru District of Eastern Province. The predominant species of fish reared was the Nile Tilapia, followed by the African Catfish and in some instances a combination of the two species were reared under polyculture. Good growth rate and survival of fish were noted to be the most important traits of economic importance to the farmers. Fish produced was mainly sold to the local community and within local markets. Traders, however, indicated that the demand for fish was much higher than the supply, hence also sourced fish from Lake Victoria in Nyanza for sale. It was also indicated that the taste of fish differed greatly depending on the source, with wild fish strains from Lake Victoria having a “sweeter” taste than the farmed strains. Strains of fish selected for improved growth and reproduction were not available for aquaculture. Feeds and feeding management of farmed fish was also a challenge. It was evident that there is a great need for supportive research on environmental impacts, productivity and quality of fish reared, and marketing of fish products within the riverine environments of Kenya. Key words: aquaculture, fish marketing, traits of economic importance
Show more [+] Less [-]Productivity of Abergelle, Central Highland and Woyto-Guji goat breeds in Ethiopia
2020
Jembere, Temesgen | Haile, Aynalem | Dessie, Tadelle | Kebede, Kefelegn | Okeyo Mwai, Ally | Rischkowsky, Barbara A.
Flock structure, level of production, and marketing of three Ethiopian goat types kept under different production systems
2014
Tadesse, D. | Urge, Mengistu | Animut, G. | Mekasha, Yoseph
This study was conducted to characterize three Ethiopian indigenous goat types in terms of their composition and dynamics, productivity, and marketing. A set of semi-structured questionnaire was used to collect information from 155 goat owners based on single-visit-interviews. The study indicates that breeding females constituted the largest average flock composition followed by weaners and kids. Goat owners in the study areas relied mainly on births and purchases to build their flock while sales and deaths were the major routes of disposal. Lower commercial offtake (28%) and higher mortality (24%) rates were estimated for all study areas but the figures were lower in pastoral and agro-pastoral systems. On average, female goats in the study area gave first birth at the age of 1.4 years, kidded every 8.6 months and stayed on production/kidding for about 5 years, giving daily milk yield of 0.37 liter. Based on the estimates given by respondents, Somali and highland goats were characterized to have bigger age at first kidding and longer kidding life time, respectively. For other traits such as kidding interval and daily milk yield, no significant performance difference was observed among the goat types. In all study areas, goats were sold mainly at the farm gate when money is needed to buy grains and other farm inputs. Average age at sale/slaughter of male goats was about 1.4 years. Consumers, producers, traders, butchers and brokers were the major buyers of live goats in the study areas. The participation of goat producers in the market was constrained by seasonality of market, low price, and lack of market information and infrastructure.
Show more [+] Less [-]Effect of boar genotype on reproductive performance of the local sows of Zimbabwe
2003
Ncube, M. | Dzama, K. | Chimonyo, M. | Kanengoni, A. | Hamudikuwanda, H.
The effect of boar genotype on the reproductive performance of local sows was investigated. Large White (LW) and local Mukota boars were mated to 20 sows over 3 parities and the performance of the sows and litters were compared up to weaning. Data on the gestation length, number of piglets born alive (NBA), the number of piglets born dead (NBD), number weaned and the sex ratio were recorded. The weights of the piglets were recorded within 16 hours of birth and also at weaning. No creep feeding of the piglets was done and weaning was done at 35 days of age. There were no differences in the number of services per conception and the NBD. Litter size at birth, NBA and the number of piglets that were weaned were higher in sows mated to LW boars than to indigenous boars. These findings indicate that imported boars can be used under smallholder pig production systems as they complement traits of both the local and imported breeds.
Show more [+] Less [-]Simulation of costs and benefits of supplementing milking cows with legumes during the dry season in two hillside regions of Nicaragua
2008
Holmann, Federico J. | Tiemann, Tassilo T.
Objectives of this study were to compare costs and expected benefits of feed supplementation in cattle with alternative shrub legumes during the dry season using as a case study the hillsides of Central Nicaragua. The information used was gathered in a survey of 32 farms in the states of Boaco and Chontales in Central Nicaragua. The survey was designed to determine herd structure, land use patterns, milk and beef production, and use of inputs for animal nutrition, in order to estimate production, reproductive parameters and employment of family/contracted labor, as well as indicators of profitability of the alternatives under study. To calculate the economic return to the investment in alternative forages, a simulation model that applies optimization techniques through linear programming, implemented as a spreadsheet, was used to perform an ex ante evaluation of the costs and benefits of different land use alternatives and of interactions between technological components and biological productivity. The model compares the costs and benefits of the traditional feeding system versus an improved feeding system. The traditional system consists of grazing naturalized pastures (Hyparrhenia rufa) during the rainy season. In the dry season producers supplement the herd with small areas of king grass (Pennisetum spp.). The improved feeding system consists of establishing forage legumes for dry season feeding as a supplement to replace king grass during the dry season. Supplements to evaluate are the shrub legume Calliandra calothyrsus as partial replacement of the herbaceous high quality legume Vigna unguiculata, commonly known as Cowpea. Under the new feeding system, herd size can be increased by 60% due in part to the increase in stocking rate as well as to the increase in the quality of the diet offered with higher protein content. This increase in herd size raises both milk and beef output that generates an increase in farm income by 1.8 times more (i.e., from $1,314/farm/yr to $2,386). The economic return to family labor is increased by 20% to $ 5.26/day equivalent to 2.3 times higher than the local wage rate. The adoption of Vigna (Cowpea) after the harvest of maize/beans and a shrub legume as Calliandra to replace king grass seem to have the potential to significantly improve the productivity in smallholder farms. with the resulting increase in the economic return to family labor.
Show more [+] Less [-]Long-term influence of large forest fire on ground vegetation
2016
Purina, L., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Straupe, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Liepa, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Libiete, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Zadina, M., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Jansons, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Fire is a major disturbance in hemiboreal forests; it affects not only trees, but also ground vegetation. Previous studies have analysed the succession of ground vegetation after the fire, but not addressed the impact of the size of the burned area on revegetation of it. Therefore, the aim of our study was to assess the differences in post-fire ground vegetation in relation to the distance from the edge of the affected area. Vegetation data were collected using Braun-Blanquet method in three sites (122 sample plots) affected by forest fire and five clearcuts (not affected by fire) (92 plots), all regenerated by Scots pine 6 – 7 years before the assessment. The number of ground vegetation species (in all sites predominantly birds or wind dispersed) as well as their projective cover was not affected by the distance from the nearest edge of burned or clearcut, except in burned sites on dry sand soil (Vaccinosa and Myrtillosa), where herbaceous plant and shrub cover was decreasing (from 23.5% to 11.6%) and bryophyte and lichen cover – increasing (from 3% to 13.9%) with an increasing distance from the edge of the area. The total number of plants in burned areas was twice smaller than in clearcut in the same soil conditions but such large difference in projective cover was not observed. There were no significant differences between burned and clearcut areas in respect to Ellenberg’s indicator values on both soil types, as well as no trend in Ellenberg’s values for soil moisture in relation to distance from the nearest stand edge.
Show more [+] Less [-]Genetic differences in needle cast damage of Scots pine (Pinus sylvestris L.)
2016
Polmanis, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia) | Klavina, D., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Gaitnieks, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Baumanis, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The impact of climatic and genetic factors on needle cast damage, as well as relationship between the degree of damage and survival and growth of trees was evaluated in the study. The analysis was done in two series of experiments, both established in two locations in Latvia (central and eastern part). Needle cast damage (in 5 grade scale) as well as the height and height increment, diameter of root collar and survival of trees were assessed. Results suggest that the degree of needle cast damage was influenced by the genetic, as well as climatic factors, and also their interaction. The average degree of needle cast damage in experiment of open-pollinated families was 4.7 ± 0.01 in central and 4.6 ± 0.03 in eastern Latvia; in the experiment of control-crossed families it was 4.6 ± 0.02 in central and 3.4 ± 0.04 in eastern Latvia. The impact of genetics on the needle cast damage degree was statistically significant (p is less than 0.05), and this effect was observed when any of growth traits (diameter, height or height increment) was used as a covariate in analysis. Results suggest the potential to select more resistant families, since the genetic correlation of grade of the damage between locations was significant (r = 0.40 - 0.72) and therefore improve also the growth of trees, since the grade of the damage had a negative correlation with growth traits both at provenance and family mean level (r = -0.69 and r = -0.42; p is less than 0.01).
Show more [+] Less [-]Impact of needle cast damage on sanitary condition in young Pinus sylvestris stands in central Latvia
2016
Polmanis, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);Latvia Univ. of Agriculture, Jelgava (Latvia) | Miezite, O., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Baumanis, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Recent studies have demonstrated the occurrence of different needle cast (Lophodermium spp.) species in young Scots pine Pinus sylvestris L. stands in different regions of Latvia. The impact of these fungi has been known also historically, but is predicted to increase in future due to climate changes that are forecasted to have a positive impact on presence and vigour of various species of fungi. The aim of the study was to characterize the needle cast damage in young Scots pine stands in central Latvia. Material was collected in 12 Scots pine stands at the age of 3 to 26 years in 28 plots with a total area of 8.1 ha in the middle of two consecutive growing seasons (years 2012 and 2013). The impact of disease was visually assessed using a 5 grade scale, depending on the proportion of damaged (brown) one-year old needles. Incidence of damaged trees (P, %) and damage intensity (R, %) was calculated and used to characterize the occurrence and severity of the infection in the stands as well as its link to other stand parameters. Damage incidence (ranging from 20 to 100%), as well as the intensity (from 4 to 35%) was slightly (incidence-also significantly) higher in 2013 in comparison to 2012; correlation between those two parameters was strong in both years (r = 0.94 and r = 0.84, respectively). The stand age, density (ranging from 1200 to 6900 trees haE-1) and tree height did not significantly correlate with the damage incidence or intensity. Forest type (Hylocomiosa or Myrtillosa mel.) was not a significant factor, too.
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