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31.
A study was conducted from November 2009 to March 2010 with the objective of identifying the major causes of skin rejection on fresh, pickled, and wet blue skins at Modjo Mesaco Global tannery. A total of 401 fresh and 1,873 pickled and wet blue skins from the routine production system of the tannery were used. Overall, high prevalence of sheep ked (100%) followed by biting louse (64.4%), tick (50%), and sucking louse (45.8%) were observed on fresh sheep pelts, while, on fresh goat pelts, a high prevalence of sucking louse (54.5%), followed by tick (50%), and biting louse (35.5%) were observed. From the total of 90 rejected pickled and wet blue skins of sheep and goats, 98.8% were “ekek” and scratch, 85.6% sheep and goat pox, 74% poor substance, 73.3% heat, 72.2% scar, and 52.2% knife cut-in skins. Large number of skins rejections was recorded in large-sized skins (29.8%), and the lowest observed was in medium-sized skins (11.1%). There were highly statistically significant association (p < 0.05) between size and grades of shoat skins. Ekek and scratches together with sheep and goat pox were the common skin defects that hamper skin quality. However, there was no significant association (p > 0.05) between sheep and goat skins. Ekek and scratch caused high rejection of skin and entailed serious economic loss in terms of foreign exchange earning to Ethiopia. Therefore, the main causes of skin rejection and factors that cause downgrading of skin should be controlled.  相似文献   
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介孔氧化硅SBA-15对铯的吸附性能研究   总被引:1,自引:0,他引:1  
SBA-15是具有较大孔径和良好的热稳定性的多孔硅基分子筛,在吸附分离领域有着广阔的应用前景。合成了介孔硅基材料SBA-15,对其进行了TEM和FTIR表征,并进行了SBA-15对铯的吸附性能研究,探讨了不同的p H值,铀初始浓度,吸附材料用量,反应时间以及离子强度等条件对吸附性能的影响。结果表明,在p H=6,吸附时间120 min,铯初始浓度为40 mg/L时,SBA-15对铯的吸附容量达到26.31 mg/g。较高的p H值有利于铯的吸附,而离子强度对吸附明显有抑制作用。吸附等温线拟合结果符合Langmuir等温模型,拟一级动力学模型能较好地描述反应动力学。  相似文献   
34.
This study reports a prevalence and risk factor survey of brucellosis in small ruminants in Southern Zone of Tigray Region, Northern Ethiopia between October 2011 and April 2012 to determine the sero-prevalence of small-ruminant brucellosis and to identify associated risk factors for the occurrence of disease in small ruminants under extensive production system. Multistage random sampling was followed to select locations, flocks, and individual animals. Laboratory analysis of serum samples provided sero-prevalence estimates for flocks and geographic location. Information on risk factors at the individual and flock level was obtained by examination of individual animal and a questionnaire interview to flock owners. The overall individual animal-level sero-prevalence of brucellosis in small ruminants was 3.5 % and flock level sero-prevalence was 28.3 %, and the within-flock sero-prevalence was ranged from 0 % to 22.2 % based on the Complement Fixation Test. Multivariable logistic regression showed that the major risk factors for flock level sero-positivity were flock size and abortion history. This study showed that small-ruminant brucellosis is prevalent in the study area. Larger flock size and history of previous abortion in the flock were major risk factors identified for sero-positivity of small-ruminant brucellosis.  相似文献   
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The study was conducted to evaluate reproductive performances and estimate genetic parameters for reproduction traits in Arsi-Bale goats. A total of 792 kidding records collected from 2001 to 2007 were used. Parity of dam, year, season and type of kidding were investigated as fixed effects by PROC GLM of SAS. Derivative-Free Restricted Maximum Likelihood (DFREML) method was used to estimate genetic parameters by fitting four animal models. Parity of dam and year of kidding influenced (P < 0.05) all the traits. The overall means for age at first kidding (AFK), kidding interval (KI), litter size at birth (LSB), litter size at weaning (LSW), litter weight at birth (LWB), litter weight at weaning (LWW), abortion and dystocia were 574.9 ± 8.3 days, 280.0 ± 13.7 days, 1.6 ± 0.03, 1.37 ± 0.03, 3.7 ± 0.08 kg, 9.11 ± 0.38 kg, 3.8% and 0.13%, respectively. The estimates of direct additive heritability for the traits, except for abortion and dystocia, under the best model (direct animal for AFK and repeatability model for other traits) were 0.245 ± 0.19, 0.060 ± 0.08, 0.074 ± 0.05, 0.006 ± 0.05, 0.125 ± 0.05, 0.053 ± 0.07, respectively, while the corresponding permanent environmental effects were 0.00 ± 0.00, 0.07 ± 0.07, 0.08 ± 0.05, 0.172 ± 0.06, 0.03 ± 0.04 and 0.07 ± 0.05, respectively. Repeatability estimates for KI, LSB, LSW, LWB and LWW were 0.13, 0.15, 0.18, 0.16 and 0.12, respectively. Genetic correlations between reproductive traits vary from medium to high. Arsi-Bale goats have good reproductive performance with low incidence of reproductive disorder. Except for AFK, other traits have low estimates of heritabilities with high genetic correlation among the traits. Repeated measures of the traits are needed before deciding to keep or cull the animal.  相似文献   
37.
The study was conducted in the central rift valley of Ethiopia to define Arsi-Bale goat keepers’ breeding objectives and breeding practices and to describe flock management practices and rate of inbreeding in Arsi-Bale goat population. Two-stage sampling techniques were employed to select study sites and 202 respondents. Semistructured questionnaire and group discussion were used to collect the required information. Data were analyzed using statistical package for social science. Rate of inbreeding in the population and indices were also calculated. On average, each respondent holds around 12 goats in which 30.7, 66.6 and 2.7% were males, females and castrates, respectively. The most important purpose of goat production in the study area was for milk utilization. Farmers have multiple breeding objectives and they considered both subjective and objective selection criteria with slightly more emphasis on morphological characteristics for buck selection than replacement doe selection. Only 39.1% (n = 79) of respondents have their own breeding bucks. None of the respondents practiced controlled mating. Average rate of inbreeding in the population was around 0.20. Arsi-Bale goats are found to be adaptive to the prevailing condition. Therefore, any breed improvement strategy to be designed or implemented in the study area and other similar areas should consider important traditional breeding practices.  相似文献   
38.
为了解河南省小麦主产区菲利普孢囊线虫与禾谷孢囊线虫的发生情况,作者分别于2014年和2015年5月通过随机采样调查方法,从商丘、漯河、许昌、新乡、鹤壁、安阳、濮阳、焦作等八地区19个县市采集到61份小麦孢囊线虫(CCN)的根围土壤样品,分析了样品的孢囊密度,发现采自商丘、新乡、鹤壁、安阳和濮阳地区的样品孢囊密度普遍较高,CCN发生比较严重;利用双重PCR技术对样品的CCN种类进行了快速检测鉴定,检测出禾谷孢囊线虫单一侵染的样品有33份;菲利普孢囊线虫单一侵染的样品有9份,与禾谷孢囊线虫复合侵染的样品有19份。菲利普孢囊线虫主要采自商丘、漯河、许昌、新乡、焦作等五个地区,其中商丘地区发生比较普遍。该研究可为河南省小麦的品种布局和孢囊线虫的综合防治提供指导。  相似文献   
39.
The objective was to assess rumination behaviour and, more specifically, the intra-individual and inter-individual variation of the frequency of chews during rumination (per min) in five Blackhead sheep fed hay at a level of 100% maintenance (experimental period [EP] I), 50% maintenance (EP II) and ad libitum (EP III). Animals ruminated in EP II less (416 min/day) than in EP I and III (558 and 592 min/day, respectively). Mean inter-individual coefficents of variation (CV) of frequency (defined as number of chews/duration of chewing per cycle) were 12.5%, mean intra-individual CV were 2.5%. The respective CVs for the duration of rumination per day were 8.1 and 9.7%, respectively. The level of intake influenced the frequency of chews significantly. It is concluded that the frequency of chews has to be considered in studies investigating chewing behaviour of ruminants. Under the experimental conditions investigated, number of chews during rumination per day could be estimated by the frequency of chewing with nearly the same precision as by using the duration of rumination per day.  相似文献   
40.
In 1995, a new species of Trichinella (Trichinella zimbabwensis) was discovered in farmed Nile crocodiles (Crocodylus niloticus) in Zimbabwe, where the mode of transmission was the consumption of the meat of slaughtered crocodiles, used as feed. To determine whether T. zimbabwensis affects poikilotherm vertebrates in the wild, monitor lizards (Varanus niloticus) and Nile crocodiles were collected in Zimbabwe and Mozambique. In 5 (17.6%) of the 28 monitor lizards from Zimbabwe, T. zimbabwensis larvae were identified. For the wild Nile crocodiles from Mozambique, species-level identification was not possible, yet immunohistochemical analysis revealed that 8 (20%) of the 40 animals harboured non-encapsulated Trichinella sp. larvae, which probably belonged to T. zimbabwensis. This is the first report of T. zimbabwensis in wild reptiles, and the findings are consistent with reports that vertebrates with scavenger and cannibalistic behaviour are the most important hosts of Trichinella spp. The wide distribution of monitor lizards and crocodiles in Africa and the development of national crocodile breeding programs in many African countries should be taken into consideration when evaluating the risk of transmission of this parasite to mammals, including humans.  相似文献   
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