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An experiment was conducted to assess the effect of substitution of concentrate mix with Sesbania sesban on feed intake, digestibility, average daily gain (ADG), and carcass parameters of Arsi-Bale sheep. The experiment employed 25 male sheep with mean (±standard error) initial body live weight (BLW) of 19.1?±?0.09 kg. The experiment consisted of 7 days of digestibility and 90 days of feeding trials followed by carcass evaluation. The experiment employed a randomized complete block design with five treatments and five blocks. Treatments comprised of grass hay alone fed ad libitum (GHA; control), GHA?+?100 % concentrate mix (CM) consisting of wheat bran and noug seed cake at a ratio of 2:1 (0 S. sesban), GHA?+?67 % CM?+?33 % S. sesban (33 S. sesban), GHA?+?33 % CM?+?67 % S. sesban (67 S. sesban), and GHA?+?100 % S. sesban (100 S. sesban). Total dry matter intake (DMI) was higher (p?<?0.001) for sheep in 0 S. sesban–100 S. sesban (800–821 g/day) compared to sheep in control (611 g/day). However, the effect of S. sesban inclusion (0 S. sesban–100 S. sesban) on total DMI was quadratic, and DMI declined after 67 S. sesban. Digestibility of DM, organic matter (p?<?0.01), and crude protein were higher (p?<?0.001) in supplemented group compared to the control. ADG, feed conversion efficiency (ADG/DMI), slaughter BLW, hot carcass weight, and total edible offals were higher (p?<?0.05–0.001) for sheep in 0 S. sesban–100 S. sesban than those in control. Increased level of S. sesban inclusion, in general, reduced growth and carcass parameters in this study. However, there was no difference between 0 S. sesban and 33 S. sesban in most parameters studied. Thus, it can be concluded that S. sesban could substitute a concentrate when it accounted for up to 33 % of the mix.  相似文献   
2.
Contents Five tropically adapted buck breeds extensively managed in Ethiopia were studied to determine possible effects of breed and age on body size and testicular traits. In all, 177 bucks were selected following stratified random sampling, and evaluated in three age groups: <14 months (young), 14–19.5 months (intermediate) and 19.6–24 months (old). The breeds studied were Arsi-Bale (AB; N = 35), Central Highlands (CH; N = 33), Afar (N = 35), Boran (N = 36) and Woito-Guji (WG; N = 38). In all the three age groups, Boran and CH bucks were the heaviest (p < 0.05), Afar were the lightest, and AB and WG were in between. The highest body weight (BW) was achieved in the intermediate age group for Afar, but in the oldest age group for the other breeds. In the youngest age group, scrotal circumference (SC) was the widest (p < 0.05) for Boran and CH and the narrowest for Afar, AB and WG, while in the intermediate and the oldest age groups, Boran showed the widest SC. Boran, WG and CH had higher (p < 0.05) testicular weight (TW) than Afar and AB in the youngest age group. Boran retained the highest (p < 0.05) TW in the intermediate and the oldest age groups, while in the oldest age group WG and AB medium TW and Afar had the lowest TW. However, Afar had the highest TW expressed as percentage of BW. SC was well correlated with TW (p < 0.001; r  = 0.74) and BW (p < 0.001; r  = 0.61), indicating a linear, positive association between BW and TW (p < 0.001; r  = 0.51). In conclusion, body size and testicular traits of Ethiopian bucks under an extensive management system are influenced differently by breed and age group.  相似文献   
3.
Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement.  相似文献   
4.
A study was conducted to assess the effect of genetic and non-genetic factors (litter size, sex of lamb, and parity of dam) on pre-weaning growth performance of crossbred lambs (75 % Dorper (DR) 25 % indigenous lambs; and 50 % Dorper 50 % indigenous lambs) under semi-intensive husbandry practices in eastern Ethiopia. Data from a total of 275 Dorper sire breed × indigenous (Blackhead Ogaden [BHO] and Hararghe Highland [HH]) crossbred lambs with different genetic group of the parental breeds were collected for three consecutive years (2009 to 2011). Pre-weaning growth performance attributes of crossbred lambs studied were birth weight, weaning weight, and pre-weaning average daily gain. Data were analyzed using the GLM procedure of SAS (2003). Breed group and non-genetic factors significantly affected pre-weaning growth performance. Lambs with 75 % Dorper and 25 % indigenous had higher (P?<?0.01) birth weight than 50 % DR and 50 % HH but similar to 50 % DR and 50 % BHO. Weaning weight and pre-weaning live weight gain were higher (P?<?0.01) for ¾DR¼BHO and ¾DR¼HH than 50 % Dorper inheritance. Single-born lambs had higher weight at birth, weaning weight, and pre-weaning average daily gain as compared to twins. Sex comparison is significant (P?<?0.05) and male lambs recorded highest pre-weaning growth performance compared to female counterparts. Parity, season, and lambing year significantly (P?<?0.01) influenced the pre-weaning growth of crossbred lambs. Therefore, it could be concluded that 50–75 % Dorper inheritance improved pre-weaning growth performance of indigenous breeds of Hararghe Highland and Blackhead Ogaden sheep. The result also suggested culling of ewes older than fourth parity to improve the pre-weaning growth performance of lambs.  相似文献   
5.
There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in sub‐Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thought‐out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10‐year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative public–private partnerships in joint testing of innovative market‐led seed systems, skills and knowledge enhancement, de‐risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries.  相似文献   
6.
The aim of this study was to characterize growth and sperm production parameters in Ogaden bucks fed a basal diet of hay and supplemented with agro-industrial by-products and Khat leftovers in Ethiopia. Thirty-five bucks with a mean (+/-SD) initial live body weight (BW) of 15.5 +/- 1.5 kg were randomly assigned to one of four dietary treatments for a period of 13 weeks. Treatments consisted of native hay fed ad libitum (control; C), native hay supplemented with a 1% of BW agro-industrial by-products (treatment 1; T1), native hay supplemented with Khat (Catha edulis) leftovers at a rate of 1% of BW (treatment 2; T2) and Khat leftovers fed ad libitum (treatment 3; T3). Bucks fed on T1-T3 had higher BW, body condition score, scrotal circumference (SC), testicular width and testicular length, compared to controls (P < 0.05). Also, bucks in T1-T3 had higher sperm progressive motility, sperm concentration per ml and total number of spermatozoa per ejaculate compared to controls (P < 0.05). Between treatments, bucks in T3 recorded the highest BW (17.2 +/- 0.16) and testicular size (21.1 +/- 0.17 cm). Both testicular and epididymal weight and dimensions were significantly affected (P < 0.05) by supplementation compared to controls. Testicular size was positively correlated to live BW (r = 0.53, P < 0.001). SC was positively correlated with ejaculate volume (r = 0.37, P < 0.001), sperm mass activity (r = 0.65, P < 0.001) and individual sperm progressive motility (r = 0.40; P < 0.001). Supplementation with Khat leftovers induced the highest improvement in live BW, testicular size, semen production and sperm motility in Ogaden bucks and can possibly be considered as a feed supplement to enhance goat production under smallholder livestock farming system in Ethiopia.  相似文献   
7.
A study was carried out to understand the needs and perception of goat keepers in selected areas of Ethiopia in order to identify the breeding objectives, traits of preference, and production constraints that may be required in designing improvement programs. The study was conducted in three districts (Bati, Meta, and Kebri-Beyah) representing the lowland crop–livestock (LLCL), highland cereal–livestock (HLCL), and pastoral/agropastoral (P/AP) systems, respectively. The study targeted the three goat types (Bati, Hararghe Highland, and Short-eared Somali) found in Ethiopia. Households in all systems considered meat production, milk production, and income generation as major purpose of keeping goats. However, those in the low rainfall and arid environments of P/AP systems gave high ranking to adaptability to harsh environments and also to building social and religious values. In LLCL and HLCL systems, goat skin and manure were more valued than in P/AP systems. Principally, in P/AP systems, the awareness of households to skin utilization and marketing was very low. Despite diverse multiple breeding objectives identified, household breeding practices were affected by constraints related to disease prevalence, feed shortage and water scarcity, and lack of awareness on skin management, utilization, and marketing. Thus, designing and implementing of sustainable goat improvement programs is an overriding priority and should take into account the breeding objectives and knowledge of goat keepers in all production systems. Along with the breed improvement, a strategy should also be devised to enhance the utilization and marketing of goat skin at all levels of production.  相似文献   
8.
In this study, feed intake and sperm morphology were evaluated in Ogaden bucks supplemented with either agro-industrial by-products or khat leftover. Thirty-five bucks at about 1 year of age, and 15 ± 1.5 kg initial body weight, were involved in a 12-week feeding programme that had four diet groups. The control (C) diet comprised grass hay alone, fed ad libitum ; treatment 1 (T1) comprised grass hay ad libitum supplemented with a mix of agro-industrial by-products at 1% of body weight (BW); treatment 2 (T2) comprised grass hay ad libitum supplemented with khat leftovers at 1% of BW; and treatment 3 (T3) comprised khat leftover alone, fed ad libitum . Bucks in T1–T3 consumed the highest (p < 0.001) dry matter (DM), crude protein (CP), organic matter (OM) and gross energy (GE) compared with control. Among the treatment groups, DM, OM and GE intakes were higher (p < 0.05) in T3 and T2, while CP intake was highest (p < 0.05) in T1. T1 and T3 improved (p < 0.001) the percentage of morphologically-normal spermatozoa in comparison with C, with bucks in T3 being best. The proportion of total abnormal sperm head shapes and proximal cytoplasmic droplets was lowest (p < 0.01) in T1 and T3 and highest in C. Although feeding with T1 improved feed intake and sperm morphology, feeding with T3 showed the highest response. Thus, we conclude that T3 and T1 could be utilized as feedstuff to improve sperm morphology in goats under the smallholder farming system in Ethiopia.  相似文献   
9.

Ethiopia is home to a diverse gene pool of indigenous sheep populations. Therefore, a better understanding of genetic variation holds the key to future utilization through conservation. Three of these breeds, Afar, Blackhead Somali, and Hararghe Highland, are found in eastern Ethiopia where they contribute significantly to the livelihood of most pastoralist, agro-pastoralist, and smallholder farmers. These indigenous sheep are recognized on the basis of morphotype and their genetic distinction remains unknown. Here, to assess genetic variation, and matrilineal genetic origin and relationship of fat-rumed sheep found in eastern Ethiopia, 300 individuals from the three breeds were genotyped for 22 microsatellite markers and sequenced for the mitochondrial DNA displacement loop (mtDNA d-loop) region. The overall HO and HE were 0.57 and 0.75, respectively. Differentiation statistics revealed that a high proportion (97%) of the total genetic variation was explained by differences between individuals within populations. Genotype assignment independent of the population of origin showed K?=?2 to be the optimum number of genetic backgrounds present in the dataset. This result was further confirmed by mtDNA D-loop sequences comparison in which the matrilineal genetic origin of eastern Ethiopia sheep is from two haplotype groups (types A and B) among the five haplotypes globally observed. Taken together, our findings suggest that the sheep populations from three breeds originated from two ancestral genetic backgrounds that may have diverged prior to their introduction to Ethiopia. However, to obtain a complete picture of the evolutionary dynamics of Ethiopian indigenous sheep, more samples and populations from within and outside of the country will need to be analyzed.

  相似文献   
10.
Tropical Animal Health and Production - The study was carried out in Bensa district of Sidama zone, Southern Ethiopia. Agro-ecologically, the study sites were classified into highland and...  相似文献   
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