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S. Gizaw J.A.M. van Arendonk A. Valle‐Zárate A. Haile B. Rischkowsky T. Dessie A.O. Mwai 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(5):350-357
A simulation study was conducted to optimize a cooperative village‐based sheep breeding scheme for Menz sheep of Ethiopia. Genetic gains and profits were estimated under nine levels of farmers' participation and three scenarios of controlled breeding achieved in the breeding programme, as well as under three cooperative flock sizes, ewe to ram mating ratios and durations of ram use for breeding. Under fully controlled breeding, that is, when there is no gene flow between participating (P) and non‐participating (NP) flocks, profits ranged from Birr 36.9 at 90% of participation to Birr 21.3 at 10% of participation. However, genetic progress was not affected adversely. When there was gene flow from the NP to P flocks, profits declined from Birr 28.6 to Birr ?3.7 as participation declined from 90 to 10%. Under the two‐way gene flow model (i.e. when P and NP flocks are herded mixed in communal grazing areas), NP flocks benefited from the genetic gain achieved in the P flocks, but the benefits declined sharply when participation declined beyond 60%. Our results indicate that a cooperative breeding group can be established with as low as 600 breeding ewes mated at a ratio of 45 ewes to one ram, and the rams being used for breeding for a period of two years. This study showed that farmer cooperation is crucial to effect genetic improvement under smallholder low‐input sheep farming systems. 相似文献
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Mirkena T Duguma G Willam A Wurzinger M Haile A Rischkowsky B Okeyo AM Tibbo M Solkner J 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2012,129(3):244-253
Based on the results of participatory approaches to define traits in the breeding objectives, four scenarios of ram selection and ram use were compared via deterministic modelling of breeding plans for community-based sheep breeding programmes in four diverse agro-ecological regions of Ethiopia. The regions (and production systems) were Afar (pastoral/agro-pastoral), Bonga and Horro (both mixed crop-livestock) and Menz (sheep-barley). The schemes or scenarios differed in terms of selection intensity and duration of ram use. The predicted genetic gains per year in yearling weight (kilograms) were comparable across the schemes but differed among the breeds and ranged from 0.399 to 0.440 in Afar, 0.813 to 0.894 in Bonga, 0.850 to 0.940 in Horro, and 0.616 to 0.699 in Menz. The genetic gains per year in number of lambs born per ewe bred ranged from 0.009 to 0.010 in both Bonga and Horro. The predicted genetic gain in the proportion of lambs weaned per ewe joined was nearly comparable in all breeds ranging from 0.008 to 0.011. The genetic gain per year in milk yield of Afar breed was in the order of 0.018 to 0.020 kg, while the genetic gain per generation for greasy fleece weight (kg) ranged from 0.016 to 0.024 in Menz. Generally, strong selection and shorter duration of ram use for breeding were the preferred options. The expected genetic gains are satisfactory but largely rely on accurate and continuous pedigree and performance recording. 相似文献
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Aynalem Haile Solomon Gizaw Tesfaye Getachew Joaquín P. Mueller Peter Amer Mourad Rekik Barbara Rischkowsky 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(5):319-328
Ethiopia has a large and diverse population of small ruminants, which contribute substantially to the livelihood and income of the rural poor and the country at large. However, the sector faces a number of challenges. Productivity per animal and flock offtake are both very low. Reasons attributed for the apparent low productivity are as follows: absence of appropriate breeding programmes, lack of technical capacity, inadequate and poor‐quality feeds, diseases leading to high lamb mortality, and underdeveloped markets in terms of infrastructure and information. Historically, sheep and goats have received little policy or investment attention. Genetic improvement of small ruminants could contribute to bridging the productivity gap. In the past, the government of Ethiopia has placed much emphasis on importing exotic genetics and cross‐breeding with local stock as a strategy for genetic improvement. However, this has not led to a significant productivity improvement and the programmes have generally been unsustainable. Currently, there is a change in approach and a recognition of the need to focus genetic improvement efforts on the local genetic resources that are well adapted to the diverse agro‐ecologies and production environments in the country. Community‐based breeding programmes (CBBPs), which focus on indigenous stock and consider farmers’ needs, views, decisions and active participation, from inception through to implementation, have been identified as programmes of choice. The Ethiopian government and the private sector need to invest in strategic areas around CBBPs to make the programme work for the poor and be sustainable in low‐input systems. 相似文献
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Nguluma A. S. Hyera E. Nziku Z. Shirima E. M. Mashingo M. S. H. Lobo R. N. B. Getachew T. Rischkowsky B. Haile A. 《Tropical animal health and production》2020,52(6):2955-2967
Indigenous breeding practices of the farmers and the livestock production system form the bases for designing community-based breeding programs. The aim of this study was to characterize production system and examine breeding practices of the indigenous goat farmers in Hai district in Northern Tanzania to determine their relevance in establishing a community-based breeding program in the area. A cross-sectional survey was conducted in which information was collected from 160 households randomly selected from 6 villages. Average household herd was 29.2 goats with majority keeping less than 20 goats. Major reasons for keeping goats were income generation, meat and milk production. Controlled mating was practiced mainly using apron and castration. Castration was practiced using traditional methods to control breeding and improve meat quality. Farmers in the study area had large goat flocks and a small buck to doe ratio. Farmers do not have a good understanding of inbreeding and its negative effects but practise other good breeding methods which could impact the productivity of their animals. Diseases and feed shortages were the main constraints to production. Opportunities exist for a community-based breeding program to genetically improve goat productivity.
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Asrat Tera Dolebo Aberra Melesse Cristian Porcu Tesfaye Getachew Aynalem Haile Mariem Rouatbi Zelalem Abate Muluken Zeleke Barbara Rischkowsky Joram M. Mwacharo Mourad Rekik 《Animal Science Journal》2020,91(1)
To understand the ovarian basis for prolificacy of Bonga sheep, a total of 31 ewes were selected based on litter size (LS) records and divided into two groups: High Prolificacy (HP) (n = 20) with LS ≥ 2 and Low Prolificacy (LP) (n = 11) with LS = 1. At a synchronized estrus, follicular dynamics were determined using transrectal ultrasonography. Plasma estradiol concentrations were also monitored. In total 27 ewes were observed in estrus being 9/11 LP (82%) and 18/20 HP (90%). On the day of estrus (day 0), the mean number of large follicles was higher (p < .05) in HP (1.78 ± 0.19) than in LP (1.0 ± 0.28) ewes. Prior to estrus, more (p < .05) medium follicles were visible for HP compared to LP ewes. Plasma estradiol concentrations were higher in HP compared to LP ewes (18.91 ± 0.41 vs. 14.51 ± 0.65 pg/ml; p < .05) and similarly was ovulation number (2.3 ± 0.15 vs. 1.28 ± 0. 14; p < .05). Higher ovulation rates and litter size in Bonga sheep are evidenced by the previous presence of more large follicles and the existence of co‐dominance effects as most likely medium follicles are selected to ovulate. 相似文献
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The presence of cattle in the Amazon region is controversial in terms of their ecological suitability and profitability compared with crops. Nevertheless, they are widely distributed in the study area in north-eastern Pará and, contrary to the common image of cattle on large ranches, a high proportion of them are kept on smallholder farms. To explain their presence, cattle are assumed to have benefits beyond physical production, such as complementing resource use or representing capital. To test this hypothesis, the costs and benefits of the three main agricultural activities, cattle, cassava and black pepper production, in terms of land, labour and capital productivity, were recorded in 37 small farms over a period of 15 months. To provide a longer perspective, benefits and costs of these activities were calculated for their assumed lifetime, which in the case of cattle, assumed a stable herd, derived from a deterministic herd model. The resultant values for land, labour and capital productivity of cattle were much lower than the values derived from direct observations during the study period, and were not as high as those for cassava and black pepper. Furthermore, the analysis of resource use in the farms showed that cattle production was not usually integrated with cropping activities, did not improve the use of available labour, and competed for land. Therefore, there had to be a reason for keeping cattle beyond their physical productivity. It was deduced to be their functional quality. Cattle could be disposed of quickly and easily at any time, in order to acquire large sums of cash or the equivalent in kind. The liquidity derived from keeping living stock was not matched by other agricultural activities or by the financial market. Hence, cattle turned out to be the best instrument of finance for the smallholder. Farmers were not interested in the continuous development of their herds, or sustainable production practices, and favoured low input management. Consequently, development plans relying on long-term, continuous commitments to pasture and cattle management are inappropriate. Instead, research and extension work should focus on simple, flexible and low-cost improvements to cattle keeping on crop-livestock smallholder farms, until credit programmes are available that replace the financing function of cattle. 相似文献
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Haile A. Hassen H. Gatew H. Getachew T. Lobo R. N. B. Rischkowsky B. 《Tropical animal health and production》2018,50(3):643-650
Tropical Animal Health and Production - We generated epidemiological information on the prevalence of nematode parasites and possible resistance/resilience of goats in three areas, Bati, Shinille,... 相似文献
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GnRH and prostaglandin‐based synchronization protocols as alternatives to progestogen‐based treatments in sheep 
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下载免费PDF全文 M Rekik A Haile A Abebe D Muluneh S Goshme I Ben Salem M El‐Dine Hilali N Lassoued Y Chanyalew B Rischkowsky 《Reproduction in domestic animals》2016,51(6):924-929
The study investigated, for cycling sheep, synchronizing protocols simultaneously to the standard “P” protocol using progestogens priming with intravaginal devices and gonadotropin. In November 2014, 90 adult Menz ewes were assigned to either the “P” protocol, “PGF” treatment where oestrus and ovulation were synchronized using two injections of prostaglandin 11 days apart or a “GnRH” treatment where the ewes had their oestrus and ovulation synchronized with GnRH (day 0)–prostaglandin (day 6)–GnRH (day 9) sequence. The ewes were naturally mated at the induced oestrus and the following 36 days. Plasma progesterone revealed that 92% of the ewes were ovulating before synchronization and all, except one, ovulated in response to the applied treatments. All “P” ewes exhibited oestrus during the 96‐hr period after the end of the treatments in comparison with only 79.3% and 73.3% for “PGF” and “GnRH” ewes, respectively (p < .05). Onset and duration of oestrus were affected by the hormonal treatment (p < .05); “GnRH” ewes showed oestrus earliest and had the shortest oestrous duration. Lambing rate from mating at the induced oestrus was lower for “P” than for “PGF” ewes (55.6% and 79.3%, respectively; p < .05). The same trait was also lower for “P” than for “PGF” and “GnRH” ewes (70.4%, 89.7% and 86.7%, respectively; p < .05) following the 36‐day mating period. Prostaglandin and GnRH analogue‐based protocols are promising alternatives for both controlled natural mating and fixed insemination of Menz sheep after the rainy season when most animals are spontaneously cycling. 相似文献