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1.
This study was carried out at the Genetic Engineering Lab, College of Agriculture, University of Basrah. DNA was extracted from samples containing meat of commercial products in the Basrah markets. The products subjected to analysis using polymerase chain reaction (PCR) with species specific repeat (SSR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques based on the sequence of the mitochondrial DNA cytochrome b gene (mtDNA cyt b gene). Then digestion with the Alu l restriction enzyme to establish a differential diagnosis detects and discriminates between meat species and adulteration in the products. SSR primers were applied, has been detected amplification of the encoded gene product, generated 221 bp in some imported minced and canned meat samples. The results show that SSR analysis produced a pattern that allowed a direct identification of horse and donkey meats in some imported minced and canned meat samples (Hana, Monde and Bavaria). The amplified 359 bp gene of mtDNA cyt b gene from samples in different product was cut using Alu 1 restriction enzyme resulting in restriction fragment length polymorphism (RFLP). Alu 1 was used to distinguish between the animals meat that belong to the family or one species. The digestion of the PCR product showed differences between products. Where the fragment length generated were 74, 76 and 189 bp. It belonged to horse meat. The fraud was detected in Hana, Monde and Bavaria products available in Basrah markets showing the presence of horse meat in these products that labeled as beef meats 100%. This revealed mtDNA cyt b gene as highly conserved and consequently a good molecular marker for diagnostic studies. Thus, this technique can be applied to food authentication for the identification of different species of animals in food products.  相似文献   

2.
Erhualian and Landrace breeds are typical genetically obese and lean pigs, respectively. To compare the fecal methanogenic Archaeal community between these two pig breeds, fecal samples from different growth phase pigs were collected and used for PCR-denaturing gradient gel electrophoresis (DGGE) with two primer pairs (344fGC/519r and 519f/915rGC) and real-time PCR analysis. Results showed that a better separation and higher quality of bands pattern were obtained in DGGE proifles using primers 344fGC/519r as compared with primers 519f/915rGC. Sequencing of DGGE bands showed that the predominant methanogens in the feces of Erhualian and Landrace pigs belonged to Methanobrevibacter spp. and Methanosphaera spp. Real-time PCR analysis revealed that there was no signiifcant difference in the numbers of fecal total methanogens between Erhualian and Landrace pigs;however, pig growth phase affected the numbers of 16S rRNA genes of total methanogens and Methanobrevibacter smithii. Dissociation curves of methyl coenzyme-M reductase subunit A (mcrA) gene fragments ampliifed with real-time PCR showed all samples possessed a single peak at 82°C, which might be associated with M. smithii. Samples from the same growth phase of each breed showed good replicative dissociation curves. The results suggest that the growth phase (including diet factor) other than genotype of pig may affect the fecal methanogenic Archaeal community of pigs.  相似文献   

3.
A case study of 350 farmwomen in Croatia was conducted to contribute the understudied area of farming and entrepreneurship. The study considered the sociodemographical features of farmwoman and its influence on entrepreneurial and organization skills. Field research was conducted through a questionnaire and interviews. Results showed that farmwoman were keen to start innovations, use new technologies and start new income generating farm activities but their gender roles and process of socialization hinders them in such attempts. High statistical correlations were significant for sociodemographic status to entrepreneurial abilities like farm work organization, actual professional status to involvement in decision making and farm economic status to farm economical position (income).  相似文献   

4.
The aim of this study was to investigate the effects of enzyme supplementations on performance of growing pigs, apparent total tract digestibility (ATTD) and in vitro digestibility (IVD) of nutrients. 224 growing pigs weighing 30-4-1.2 kg were allocated to fed basal diets supplemented with 0, 0.1, 0.15 or 0.2 g/kg enzyme preparations in growth trail. Those four diets were used for in vio'o digestibility study. Pigs fed enzyme-supplemented diets improved average daily gain and decreased ratio of feed/gain (P〈0.05). Enzyme supplementations increased ATTD of dry matter, energy, crude protein, neutral detergent fiber, acid detergent fibre and hemicellulose (P〈0.05). Supplementation with enzymes improved reducing sugar production and the IVD of dry matter, crude protein, neutral detergent fiber, acid detergent fibre, total arabinoxylans, galacturonic acid, hemicellulose and cellulose. 0.015% enzyme supplementation in diets seemed to be sufficient to achieve maximum growth performance, nutrients digestibilities and reducing sugar production. Collectively, these results suggested that the supplementation of enzymes in diet increased the digestibilities of nutrients through the promotion of NSP degradation, thereby enhancing growth performance of growing pigs.  相似文献   

5.
It is necessary to take measures against infectious diseases in the Southeast Asian prawn farming industry. In giant tiger prawn (Penaeus monodon) aquaculture, diseases caused by viruses such as white spot syndrome virus (WSSV) and bacteria such as Vibrio have become a menace. Appropriate treatments of prawn culture pond's waters are advocated for preventing and controlling pathogens. The purpose of this study was to conduct an antimicrobial water treatment using a low-voltage pulsed electric field sterilization. Here we prepared a mechanical low-voltage pulsed electric field system with copper wire coiling around a titanium ring. The viability of WSSV in seawater was examined by prawn infectivity experiments. We inoculated healthy prawns (approximately 10-15 g) with the WSSV master sample that passed 0-3 times through the system. WSSV infection in prawns decreased according to the number of passes through the system. Healthy prawns survived for〉 10 days without feeding, where as prawns inoculated with the WSSV master sample showed symptoms of white spot and died in about 4 days. Two-thirds of the prawns inoculated with the WSSV master sample that was passed once through the system developed WSSV symptoms and were polymerase chain reaction (PCR) positive. However, no symptoms were observed and prawns were PCR negative when the WSSV master sample was passed three times through the system. Based on these results, we purpose that a low-voltage pulsed electric field system will serve as an efficient pond drainage sterilization system and will replace conventional treatments using chemicals such as sodium hypochlorite.  相似文献   

6.
7.
从长沙市的生猪供应链具体情况入手,对长沙市生猪供应链内各个节点间的垂直协作形式进行了研究,探讨了其目前生猪供应链节点间的垂直协作模式,并提出"垂直一体化模式"和"上游供应商+规模猪场或养殖小区(合作社)+下游屠宰加工企业"2个生猪供应链的垂直协作模式,从而实现有效地将生猪供应链内部的各个成员有效地组织起来提高整体绩效。  相似文献   

8.
Laboratory aerobic incubation was conducted for 161 d to study N mineralization and the changes of organic N fractions of nine different manures(3 chicken manures, 3 pig manures and 3 cattle manures) from different farms/locations. Results indicated that significant(P〈0.01 or P〈0.001) difference existed in N mineralization between manures. The rapid N mineralization in manures occurred during 56 to 84 d of incubation. First order exponential model can be used to describe N mineralization from chicken manures and pig manures, while quadratic equation can predict mineralization of organic N from cattle manures. An average of 21, 19 and 13% added organic N from chicken manure, pig manure and cattle manure was mineralized during 161 d of incubation. Amino acid-N was the main source of N mineralization. The changes of amino acid-N together with ammonium N could explain significantly 97 and 96% of the variation in mineralized N from manured soils and manures. Amino acid-N and ammonium N are two main N fractions in determining N mineralization potential from manures. Amino acid-N contributed more to the mineralized N than ammonium N.  相似文献   

9.
Do Land Characteristics Affect Farmers’ Soil Fertility Management?   总被引:3,自引:0,他引:3  
Soil fertility management (SFM) has important implications for sustaining agricultural development and food self-sufifciency. Better understanding the determinants of farmers’ SFM can be a great help to the adoption of effective SFM practices. Based on a dataset of 315 plots collected from a typical rice growing area of South China, this study applied statistical method and econometric models to examine the impacts of land characteristics on farmers’ SFM practices at plot scale. Main results showed that in general land characteristics affected SFM behaviors. Securer land tenure arrangements facilitated effective practices of SFM through more diversiifed and more soil-friendly cropping pattern choices. Plot size signiifcantly reduced the intensities of phosphorus and potassium fertilizer application. Given other factors, 1 ha increase in plot size might reduce 3.0 kg ha-1 P2O5 and 1.8 kg ha-1 K2O. Plots far from the homestead were paid less attention in terms of both chemical fertilizers and manure applications. Besides, plots with better quality were put more efforts on management by applying more nitrogen and manure, and by planting green manure crops. Signiifcant differences existed in SFM practices between the surveyed villages with different socio-economic conditions. The ifndings are expected to provide important references to the policy-making incentive for improving soil quality and crop productivity.  相似文献   

10.
The study was conducted to reveal P fractions and N forms changing characters during composting of pig manure with rice straw.During composting,the NH 4 +-N concentration decreased and reached at a relatively low value(〈400 mg kg-1) in the final compost,while the NO 3--N concentration increased.Total N losses mainly occurred during thermophilic phase due to the high temperature,the high NH 4 +-N concentration and the increase of pH value.Labile inorganic P was dominated in the pig manure and initial compost mixture.During composting,the proportion of labile inorganic P of total extracted P decreased,while the proportion of Fe+Al-bound P,Ca+Mg-bound P and residual P increased.The evolutions of the proportion of labile inorganic P,Fe+Al-bound P and Ca+Mg-bound P were well correlated with the changes of pH value,organic matter and C/N ratio.Therefore,composting could increase the concentration of N and P and decrease the presence of NH 4 +-N and labile P fractions which might cause environmental issues following land application.  相似文献   

11.
为合理调整猪群生产结构,最大限度地利用杂种母猪的生产力,利用SPSS 10.0软件中的相关模块,对510头杂交母猪繁殖性状间的相关关系及繁殖性状对胎次的回归关系进行了分析。结果表明:产活仔数(Y2)与总产仔数(Y1)、断奶仔数(Y3)、窝重(Y4)表现强相关,相关系数分别为0.883、0.893和0.845,并且都达到极显著水平(P<0.01),而总产仔数与断奶仔数和窝重也表现较强相关,相关系数分别为0.783和0.796,并且达到极显著水平(P<0.01)。繁殖性状对胎次(X)的回归方程如下:Y1=9.416+1.473 X-0.306 X2,Y2=9.416+1.636 X-0.333 X2,Y3=9.416+1.811 X-0.355 X2,Y4=9.416+4.865 X-0.834 X2。研究为合理利用二元或三元杂交母猪,提高商品猪生产效益提供了科学依据。  相似文献   

12.
转sFat-1基因猪生理生化指标与繁殖性能测定   总被引:1,自引:0,他引:1  
[目的]评价转sFat-1基因猪的健康状况,为猪育种选择优良个体提供依据.[方法]测定21头阴性试验对照纭和20头转sFat-1基因阳性猪15项生理生化指标和繁殖性能.[结果]部分转sFat-1基因猪肝功能受到轻度损伤,繁殖能力也有轻度下降.[结论]猪生理生化指标和繁殖性能测定能够成为转基因猪环境安全评价的有效方法之一. Abstract: [Objective] The aim was to evaluate the health of transgenic sFat-1 gene pigs in order to provide a reference for the breeding selection of pig excellent individuals.[Method]15 physiological biochemical parameters and reproductive performances of 21 negative control pigs and 20 transgenic sFat-1 gene pigs were determined. [Result] The liver functions of some transgenic sFat-1 gene pigs were hurted lightly,and the reproductive performance also decreased lightly. [Conclusion] The determination of physiological biochemical parameters and reproductive performance in transgenic pigs could be taken as one of effective methods in environmental safety evaluation of transgenic pigs.  相似文献   

13.
结合流行病学、临床症状、病理变化,采用PCR技术,对2005年1~6月间广西36个发生疫病的规模猪场提供的肝、脾、淋巴结、脑等84份组织病料进行猪繁殖与呼吸综合症(PRRS)、猪瘟(CSFV)、猪伪狂犬病(PRV)、猪圆环病毒2型(PCV-2)检测。结果,检出PRRS阳性病料37份,阳性率44%,阳性场17个,场阳性率47%;CSFV阳性病料16份,阳性率11.9%,阳性场6个,场阳性率22.2%;PRV阳性病料27份,阳性率32.1%,阳性场12个,场阳性率33.3%;PCV-2阳性病料44份,阳性率52.3%,阳性场21个,场阳性率58.3%。同时还发现组织病料和发病猪场中存在猪繁殖与呼吸综合症、猪瘟、猪伪狂犬病、猪圆环病毒2型不同程度的混合感染现象,其中PRRS、PCV-2混合感染最为严重,样品阳性率33.3%,场阳性率25%。表明广西规模猪场主要疫病十分复杂,混合感染现象比较普遍,对广西养猪业带来巨大威胁,应加强疫病的防控工作。  相似文献   

14.
The objective of this study was to evaluate the effects of elemental sulphur (S) and farmyard manure on soil pH, EC and N, S, P concentrations of tomato grown in a calcareous sandy loam soil. For this purpose, a pot experiment was conducted in greenhouse conditions. Sulphur was applied at 0, 50, 100, 150, 200, 400 mg kg~ and farmyard manure at 0, 3 ton da^-1 to the soil. Three weeks after applications, tomato seedlings were planted and 8 weeks later, the plants were harvested to determine N, S, P concentrations and dry matter yield. Soil pH and EC were determined in the soil samples taken at 3 different periods. Effects of sulphur and farmyard manure applications were not significant on N, P concentrations and dry matter yield of tomato plant. S concentration of tomato plant was increased by sulphur alone. Soil pH was decreased and soil EC was increased in both 2^nd and 3^rd soil sampling period by the sulphur applications. As a result of farmyard manure application, soil pH decreased in the 2^nd soil sampling period but increased in the 3^rd soil sampling period. Also, soil EC was significantly increased in 1^st and 3^rd soil sampling period. Farmyard manure had no significant effect on S supply to tomato plant. The N:S ratio of tomato plant was decreased by sulphur alone. However, the sulphur with farmyard manure applications decreased N:S ratio in lesser extend compared to the S applications.  相似文献   

15.
Using scanning electron microscopy, we investigated the distribution of the trichoid, basiconic, and coeloconic sensilla on the antennae of the diamondback moth (DBM;Plutella xylostella). The trichoid sensilla were the most abundant sensory organ, and the male moth antennae host signiifcantly more trichoid sensilla than female moth antennae. Conversely, basiconic and coeloconic sensilla were found more frequently on female than on male antennae. We performed experiments with various degrees of antennal ablation and demonstrated that DBM antennae played a key role in the control of mating and oviposition. We found that neither oviposition preference nor mating behaviors changed signiifcantly when less than 1/4 of both antennae were removed. However, there was a signiifcant behavioral change when the antennae were ablated by more than half. As the length of the antenna was shortened, the successful mating rate decreased and mating peak was delayed. An otherwise consistent host preference for oviposition was eliminated when both antennae were completely removed. Furthermore, we found that the number of trichoid sensilla was positively correlated with mating rate and oviposition preference. However, the numbers of basiconic and coeloconic sensilla were not correlated with mating rate and mating peak, but highly correlated with oviposition preference. Taken together, our results indicate that antennal sensory information plays a critical role in the mating and oviposition behaviors of this economically important pest.  相似文献   

16.
In field and laboratory conditions the reproductive potential (survival at different stages of development) of the Colorado potato beetle has been measured, the dependence of the parameters of insects fertility on varietal features of the feed has been investigated, the food activity of the representatives of insects from four areas of the Southern Urals has been measured, the intensity and time of hypersensitivity reactions on potato leaves has been defined. In laboratory experiments, the level of activity of hydrolytic enzymes in insects and the level of activity of these enzymes inhibitors in the leaves of three potato varieties differing in their resistance to the Colorado potato beetle have been determined. The results show that the insects-representatives of different samples have different food activity in relation to different potato varieties. High mortality rates were revealed at feeding with leaves of potato of the Bashkir variety characterized by a high level of hydrolases inhibitors and relatively rapid development of necrotic reactions after the appearance of eggs laying on the leaves. We suppose that the neerogenetic barrier appearing in the form of necrosis is the major cause of the fetal mortality of insects. The level of the content of inhibitors inactivating larvae digestive enzymes affects the survival of insects at postembryonic stages. The speed of the necrosis emergence, the level of activity of digestive enzymes inhibitors in potato can be considered as criteria for the selection of breeding material for resistance to the Colorado potato beetle.  相似文献   

17.
We represent assessment of the rats control operator's actions, starting from the placement of rat control means (chemical, mechanical and others) in the object territory until the full its elimination and followed by assessment of the probability of rat population recovery. The probability of success is evaluated when using a combination of rat control means. We took into account changes in rat population occurring in different calendar periods of the year. The proposed calculation method can be used in training programs, as well as for the local forecast of releasing objects from rats and rats' re-settling.  相似文献   

18.
The effects of different tillage systems and poultry manure on soil physical properties, performance and nutrients in sorghum were studied for three years at Owo, southwest Nigeria. There was factorial combinations of herbicide-based zero tillage (ZT), manual clearing (MC), disc ploughing (P), ploughing plus harrowing (P+H) and ploughing plus double harrowing (P+2H), and two rates of poultry manure at 0 and 7.5 Mg ha^-1. Herbicide-based zero tillage and manual clearing reduced soil temperature and conserved more water than mechanized tillage techniques. Poultry manure reduced soil bulk density and temperature and increased soil water and porosity. There was a percentage decrease of leaf N, P, K, Ca and Mg concentrations, plant height, leaf area, stem girth, root dry weight, dry matter and grain yield in ascending order for herbicide-based zero tillage, manual clearing, ploughing, ploughing plus harrowing and ploughing plus double harrowing while percentage increases were recorded in a descending order for all the various combinations of tillage with poultry manure in that order. Poultry manure in combination with tillage increased dry matter and grain yield by 33.1 and 39.5%, respectively in comparison with tillage only. The manure-zero tillage methods increased dry matter and grain yield by 8% and 15%, respectively when compared with manure-mechanized tillage methods. Zero tillage or manual clearing in combination with 7.5 Mg ha^-1 poultry manure was most suitable for sorghum cultivation.  相似文献   

19.
The responses of five inter-specific lowland rice cultivars (NERICA-L-19, NERICA-L-20, NERICA-L-41, NERICA-L-42, and NERICA-L-60) and four improved Oryza sativa cultivars (FKR 19, BW 348-1, WITA 4, and SIPI 6923033) to levels of phosphorus and nitrogen fertilization were compared on a Typic Natrustalfat Kadawa in the Nigerian Sudan Savanna in 2006 and 2007 The responses of the NERICA-L eultivars to N and P fertilization were similar to the O. sativa cultivars. In a dry year (2007), the NERICA-L cultivars gave higher yields than O. sativa cultivars. Phosphorus level did not significantly affect crop physiology, yield, and yield components of all the cultivars. Pooled across cultivars, N and P levels, days to panicle initiation, mid-flowering and maturity were, respectively delayed by 17.0, 15.6 and 6.4 days in 2007 compared to 2006. NERICA-L-42 and NERICA-L-41 were the most stable, exhibiting the least difference in duration to maturity between the two years (3.5 and 4.4 days, respectively), and could therefore be more adapted to rain-fed environments prone to frequent droughts. Increasing N levels from 0 to 120 kg hal produced yield increments of 62.9 and 37.2% in 2006 and 2007, respectively. Cultivars FKR 19 and WITA 4 gave higher yields in 2006 (3940 and 3542 kg ha^-1, respectively), while in 2007, NERICA-L-42, NERICA-L^-19 and NERICA-L-20 ranked among the highest in grain yield (3935, 3807 and 3726 kg hal, respectively) and could be recommended to resource-poor farmers. a  相似文献   

20.
The residual effect of organic and mineral fertilizers on selected chemical properties of an Alfisol in the long term soil fertility trial established in 1950 at Samaru, Nigerian savanna was assessed. The trial was left fallow for fourteen years due to lack of funds. Topsoil was collected from plots that received three levels of cow dung (D), nitrogen (N) and phosphorus (P) in all possible combinations. The soils were analyzed for selected chemical properties. Except for significant effect of applied P on available P, sole application of cow dung, N or P had no significant effect on all the measured soil properties. The interaction of D and P significantly affected the mean values of exchangeable Ca, Mg, K and ECEC in the range of 1.12-1.96, 0.62-1.11, 0.37-0.64 and 2.82-4.11 cmol/kg respectively. The most important results were the ability of the plot that received neither D nor P to significantly increase these parameters than the plots that received only one of the treatments. The results show that the fallow period has changed the effects of application of organic and mineral fertilizers on the soil chemical properties under continuous cultivation by modifying them towards those of a native savanna Alfisol.  相似文献   

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